[PATCH v2 0/7] Generic serial earlycon

[PATCH v2 0/7] Generic serial earlycon

[Rob Herring]

From: Rob Herring <robh@kernel.org>

This started out as an attempt to add arm64's earlyprintk support to ARM
in order to get an earlier, runtime setup console on multi-platform
kernels. The first issue was needing the fixmap support which
conveniently Mark Salter was working on and is mostly in place now. Like
many things on ARM and arm64 now, it then became where do I put the now
common, shared code. After digging more into various early console/printk
support, it turns out the 8250_early.c setup code was the best starting
point. 

This is tested on arm64 and ARM with pl011 and 8250. The ARM support
also requires fixmap and fixed mapping support which are not yet in place.
I have some patches in my tree to support fixmap, but they need some more
work. Fortunately, once fixmap is in place, it is just a Kconfig option
to enable earlycon support on ARM. A git tree is available here[1].

I'm also working on a follow on series which adds DT based earlycon
setup, but that is dependent on some FDT improvements to support FDT
based address translation.

Rob

[1] git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git earlycon

Rob Herring (7):
  x86: move FIX_EARLYCON_MEM kconfig into x86
  tty/serial: add generic serial earlycon
  tty/serial: convert 8250 to generic earlycon
  tty/serial: pl011: add generic earlycon support
  tty/serial: add arm/arm64 semihosting earlycon
  arm64: enable FIX_EARLYCON_MEM kconfig
  arm64: remove arch specific earlyprintk

 Documentation/kernel-parameters.txt        |   9 ++
 arch/arm64/Kconfig                         |   3 +
 arch/arm64/Kconfig.debug                   |   9 --
 arch/arm64/kernel/Makefile                 |   1 -
 arch/arm64/kernel/early_printk.c           | 158 -----------------------------
 arch/x86/Kconfig                           |   3 +
 drivers/tty/serial/8250/8250_early.c       | 138 +++----------------------
 drivers/tty/serial/8250/Kconfig            |   6 +-
 drivers/tty/serial/Kconfig                 |  18 ++++
 drivers/tty/serial/Makefile                |   3 +
 drivers/tty/serial/amba-pl011.c            |  30 +++++-
 drivers/tty/serial/earlycon-arm-semihost.c |  61 +++++++++++
 drivers/tty/serial/earlycon.c              | 152 +++++++++++++++++++++++++++
 include/linux/serial_core.h                |  16 +++
 14 files changed, 310 insertions(+), 297 deletions(-)
 delete mode 100644 arch/arm64/kernel/early_printk.c
 create mode 100644 drivers/tty/serial/earlycon-arm-semihost.c
 create mode 100644 drivers/tty/serial/earlycon.c

-- 
1.9.1

[PATCH v2 0/7] Generic serial earlycon

[Rob Herring]

From: Rob Herring <robh@kernel.org>

This started out as an attempt to add arm64's earlyprintk support to ARM
in order to get an earlier, runtime setup console on multi-platform
kernels. The first issue was needing the fixmap support which
conveniently Mark Salter was working on and is mostly in place now. Like
many things on ARM and arm64 now, it then became where do I put the now
common, shared code. After digging more into various early console/printk
support, it turns out the 8250_early.c setup code was the best starting
point. 

This is tested on arm64 and ARM with pl011 and 8250. The ARM support
also requires fixmap and fixed mapping support which are not yet in place.
I have some patches in my tree to support fixmap, but they need some more
work. Fortunately, once fixmap is in place, it is just a Kconfig option
to enable earlycon support on ARM. A git tree is available here[1].

I'm also working on a follow on series which adds DT based earlycon
setup, but that is dependent on some FDT improvements to support FDT
based address translation.

Rob

[1] git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git earlycon

Rob Herring (7):
  x86: move FIX_EARLYCON_MEM kconfig into x86
  tty/serial: add generic serial earlycon
  tty/serial: convert 8250 to generic earlycon
  tty/serial: pl011: add generic earlycon support
  tty/serial: add arm/arm64 semihosting earlycon
  arm64: enable FIX_EARLYCON_MEM kconfig
  arm64: remove arch specific earlyprintk

 Documentation/kernel-parameters.txt        |   9 ++
 arch/arm64/Kconfig                         |   3 +
 arch/arm64/Kconfig.debug                   |   9 --
 arch/arm64/kernel/Makefile                 |   1 -
 arch/arm64/kernel/early_printk.c           | 158 -----------------------------
 arch/x86/Kconfig                           |   3 +
 drivers/tty/serial/8250/8250_early.c       | 138 +++----------------------
 drivers/tty/serial/8250/Kconfig            |   6 +-
 drivers/tty/serial/Kconfig                 |  18 ++++
 drivers/tty/serial/Makefile                |   3 +
 drivers/tty/serial/amba-pl011.c            |  30 +++++-
 drivers/tty/serial/earlycon-arm-semihost.c |  61 +++++++++++
 drivers/tty/serial/earlycon.c              | 152 +++++++++++++++++++++++++++
 include/linux/serial_core.h                |  16 +++
 14 files changed, 310 insertions(+), 297 deletions(-)
 delete mode 100644 arch/arm64/kernel/early_printk.c
 create mode 100644 drivers/tty/serial/earlycon-arm-semihost.c
 create mode 100644 drivers/tty/serial/earlycon.c

-- 
1.9.1

[PATCH v2 1/7] x86: move FIX_EARLYCON_MEM kconfig into x86

[Rob Herring]

From: Rob Herring <robh@kernel.org>

In preparation to support FIX_EARLYCON_MEM on other arches, make the
option per arch.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
---
 arch/x86/Kconfig                | 3 +++
 drivers/tty/serial/8250/Kconfig | 5 -----
 2 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 25d2c6f..0fb6cfd 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -261,6 +261,9 @@ config ARCH_HWEIGHT_CFLAGS
 config ARCH_SUPPORTS_UPROBES
 	def_bool y
 
+config FIX_EARLYCON_MEM
+	def_bool y
+
 source "init/Kconfig"
 source "kernel/Kconfig.freezer"
 
diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig
index 2332991..91f1d83 100644
--- a/drivers/tty/serial/8250/Kconfig
+++ b/drivers/tty/serial/8250/Kconfig
@@ -90,11 +90,6 @@ config SERIAL_8250_CONSOLE
 
 	  If unsure, say N.
 
-config FIX_EARLYCON_MEM
-	bool
-	depends on X86
-	default y
-
 config SERIAL_8250_GSC
 	tristate
 	depends on SERIAL_8250 && GSC
-- 
1.9.1

[PATCH v2 1/7] x86: move FIX_EARLYCON_MEM kconfig into x86

[Rob Herring]

From: Rob Herring <robh@kernel.org>

In preparation to support FIX_EARLYCON_MEM on other arches, make the
option per arch.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86 at kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
---
 arch/x86/Kconfig                | 3 +++
 drivers/tty/serial/8250/Kconfig | 5 -----
 2 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 25d2c6f..0fb6cfd 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -261,6 +261,9 @@ config ARCH_HWEIGHT_CFLAGS
 config ARCH_SUPPORTS_UPROBES
 	def_bool y
 
+config FIX_EARLYCON_MEM
+	def_bool y
+
 source "init/Kconfig"
 source "kernel/Kconfig.freezer"
 
diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig
index 2332991..91f1d83 100644
--- a/drivers/tty/serial/8250/Kconfig
+++ b/drivers/tty/serial/8250/Kconfig
@@ -90,11 +90,6 @@ config SERIAL_8250_CONSOLE
 
 	  If unsure, say N.
 
-config FIX_EARLYCON_MEM
-	bool
-	depends on X86
-	default y
-
 config SERIAL_8250_GSC
 	tristate
 	depends on SERIAL_8250 && GSC
-- 
1.9.1

[PATCH v2 2/7] tty/serial: add generic serial earlycon

[Rob Herring]

From: Rob Herring <robh@kernel.org>

This introduces generic earlycon infrastructure for serial devices
based on the 8250 earlycon. This allows for supporting earlycon option
with other serial devices. The earlycon output is enabled at the time
early_params are processed.

Only architectures that have fixmap support or have functional ioremap
when early_params are processed are supported. This is the same
restriction that the 8250 driver had.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
---
v2:
- Use set_fixmap_io/ioremap instead of set_fixmap_nocache/ioremap_nocache.
- Do the mapping outside of option parsing function.
  
 drivers/tty/serial/Kconfig    |   7 ++
 drivers/tty/serial/Makefile   |   2 +
 drivers/tty/serial/earlycon.c | 152 ++++++++++++++++++++++++++++++++++++++++++
 include/linux/serial_core.h   |  16 +++++
 4 files changed, 177 insertions(+)
 create mode 100644 drivers/tty/serial/earlycon.c

diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 2e6d8dd..3b7c19b 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -7,6 +7,13 @@ if TTY
 menu "Serial drivers"
 	depends on HAS_IOMEM
 
+config SERIAL_EARLYCON
+	bool
+	help
+	  Support for early consoles with the earlycon parameter. This enables
+	  the console before standard serial driver is probed. The console is
+	  enabled when early_param is processed.
+
 source "drivers/tty/serial/8250/Kconfig"
 
 comment "Non-8250 serial port support"
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index 3680854..8af1415 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -5,6 +5,8 @@
 obj-$(CONFIG_SERIAL_CORE) += serial_core.o
 obj-$(CONFIG_SERIAL_21285) += 21285.o
 
+obj-$(CONFIG_SERIAL_EARLYCON) += earlycon.o
+
 # These Sparc drivers have to appear before others such as 8250
 # which share ttySx minor node space.  Otherwise console device
 # names change and other unplesantries.
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
new file mode 100644
index 0000000..73bf1e2
--- /dev/null
+++ b/drivers/tty/serial/earlycon.c
@@ -0,0 +1,152 @@
+/*
+ * Copyright (C) 2014 Linaro Ltd.
+ * Author: Rob Herring <robh@kernel.org>
+ *
+ * Based on 8250 earlycon:
+ * (c) Copyright 2004 Hewlett-Packard Development Company, L.P.
+ *	Bjorn Helgaas <bjorn.helgaas@hp.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/console.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/serial_core.h>
+
+#ifdef CONFIG_FIX_EARLYCON_MEM
+#include <asm/fixmap.h>
+#endif
+
+#include <asm/serial.h>
+
+static struct console early_con = {
+	.name =		"earlycon",
+	.flags =	CON_PRINTBUFFER | CON_BOOT,
+	.index =	-1,
+};
+
+static struct earlycon_device early_console_dev = {
+	.con = &early_con,
+};
+
+static void __iomem * __init earlycon_map(unsigned long paddr, size_t size)
+{
+	void __iomem *base;
+#ifdef CONFIG_FIX_EARLYCON_MEM
+	set_fixmap_io(FIX_EARLYCON_MEM_BASE, paddr & PAGE_MASK);
+	base = (void __iomem *)__fix_to_virt(FIX_EARLYCON_MEM_BASE);
+	base += paddr & ~PAGE_MASK;
+#else
+	base = ioremap(paddr, size);
+#endif
+	if (!base)
+		pr_err("%s: Couldn't map 0x%llx\n", __func__,
+		       (unsigned long long)paddr);
+
+	return base;
+}
+
+static int __init parse_options(struct earlycon_device *device,
+				char *options)
+{
+	struct uart_port *port = &device->port;
+	int mmio, mmio32, length, ret;
+	unsigned long addr;
+
+	if (!options)
+		return -ENODEV;
+
+	mmio = !strncmp(options, "mmio,", 5);
+	mmio32 = !strncmp(options, "mmio32,", 7);
+	if (mmio || mmio32) {
+		port->iotype = (mmio ? UPIO_MEM : UPIO_MEM32);
+		options += mmio ? 5 : 7;
+		ret = kstrtoul(options, 0, &addr);
+		if (ret)
+			return ret;
+		port->mapbase = addr;
+		if (mmio32)
+			port->regshift = 2;
+	} else if (!strncmp(options, "io,", 3)) {
+		port->iotype = UPIO_PORT;
+		options += 3;
+		ret = kstrtoul(options, 0, &addr);
+		if (ret)
+			return ret;
+		port->iobase = addr;
+		mmio = 0;
+	} else if (!strncmp(options, "0x", 2)) {
+		port->iotype = UPIO_MEM;
+		ret = kstrtoul(options, 0, &addr);
+		if (ret)
+			return ret;
+		port->mapbase = addr;
+	} else {
+		return -EINVAL;
+	}
+
+	port->uartclk = BASE_BAUD * 16;
+
+	options = strchr(options, ',');
+	if (options) {
+		options++;
+		ret = kstrtouint(options, 0, &device->baud);
+		if (ret)
+			return ret;
+		length = min(strcspn(options, " ") + 1,
+			     (size_t)(sizeof(device->options)));
+		strlcpy(device->options, options, length);
+	}
+
+	if (mmio || mmio32)
+		pr_info("Early serial console at MMIO%s 0x%llx (options '%s')\n",
+			mmio32 ? "32" : "",
+			(unsigned long long)port->mapbase,
+			device->options);
+	else
+		pr_info("Early serial console at I/O port 0x%lx (options '%s')\n",
+			port->iobase,
+			device->options);
+
+	return 0;
+}
+
+int __init setup_earlycon(char *buf, const char *match,
+			  int (*setup)(struct earlycon_device *, const char *))
+{
+	int err;
+	size_t len;
+	struct uart_port *port = &early_console_dev.port;
+
+	if (!buf || !match || !setup)
+		return 0;
+
+	len = strlen(match);
+	if (strncmp(buf, match, len))
+		return 0;
+	if (buf[len] && (buf[len] != ','))
+		return 0;
+
+	buf += len + 1;
+
+	err = parse_options(&early_console_dev, buf);
+	/* On parsing error, pass the options buf to the setup function */
+	if (!err)
+		buf = NULL;
+
+	if (port->mapbase)
+		port->membase = earlycon_map(port->mapbase, 64);
+
+	early_console_dev.con->data = &early_console_dev;
+	err = setup(&early_console_dev, buf);
+	if (err < 0)
+		return err;
+	if (!early_console_dev.con->write)
+		return -ENODEV;
+
+	register_console(early_console_dev.con);
+	return 0;
+}
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index f729be9..7a15b5b 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -285,6 +285,22 @@ static inline int uart_poll_timeout(struct uart_port *port)
 /*
  * Console helpers.
  */
+struct earlycon_device {
+	struct console *con;
+	struct uart_port port;
+	char options[16];		/* e.g., 115200n8 */
+	unsigned int baud;
+};
+int setup_earlycon(char *buf, const char *match,
+		   int (*setup)(struct earlycon_device *, const char *));
+
+#define EARLYCON_DECLARE(name, func) \
+static int __init name ## _setup_earlycon(char *buf) \
+{ \
+	return setup_earlycon(buf, __stringify(name), func); \
+} \
+early_param("earlycon", name ## _setup_earlycon);
+
 struct uart_port *uart_get_console(struct uart_port *ports, int nr,
 				   struct console *c);
 void uart_parse_options(char *options, int *baud, int *parity, int *bits,
-- 
1.9.1

[PATCH v2 2/7] tty/serial: add generic serial earlycon

[Rob Herring]

From: Rob Herring <robh@kernel.org>

This introduces generic earlycon infrastructure for serial devices
based on the 8250 earlycon. This allows for supporting earlycon option
with other serial devices. The earlycon output is enabled at the time
early_params are processed.

Only architectures that have fixmap support or have functional ioremap
when early_params are processed are supported. This is the same
restriction that the 8250 driver had.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
---
v2:
- Use set_fixmap_io/ioremap instead of set_fixmap_nocache/ioremap_nocache.
- Do the mapping outside of option parsing function.
  
 drivers/tty/serial/Kconfig    |   7 ++
 drivers/tty/serial/Makefile   |   2 +
 drivers/tty/serial/earlycon.c | 152 ++++++++++++++++++++++++++++++++++++++++++
 include/linux/serial_core.h   |  16 +++++
 4 files changed, 177 insertions(+)
 create mode 100644 drivers/tty/serial/earlycon.c

diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 2e6d8dd..3b7c19b 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -7,6 +7,13 @@ if TTY
 menu "Serial drivers"
 	depends on HAS_IOMEM
 
+config SERIAL_EARLYCON
+	bool
+	help
+	  Support for early consoles with the earlycon parameter. This enables
+	  the console before standard serial driver is probed. The console is
+	  enabled when early_param is processed.
+
 source "drivers/tty/serial/8250/Kconfig"
 
 comment "Non-8250 serial port support"
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index 3680854..8af1415 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -5,6 +5,8 @@
 obj-$(CONFIG_SERIAL_CORE) += serial_core.o
 obj-$(CONFIG_SERIAL_21285) += 21285.o
 
+obj-$(CONFIG_SERIAL_EARLYCON) += earlycon.o
+
 # These Sparc drivers have to appear before others such as 8250
 # which share ttySx minor node space.  Otherwise console device
 # names change and other unplesantries.
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
new file mode 100644
index 0000000..73bf1e2
--- /dev/null
+++ b/drivers/tty/serial/earlycon.c
@@ -0,0 +1,152 @@
+/*
+ * Copyright (C) 2014 Linaro Ltd.
+ * Author: Rob Herring <robh@kernel.org>
+ *
+ * Based on 8250 earlycon:
+ * (c) Copyright 2004 Hewlett-Packard Development Company, L.P.
+ *	Bjorn Helgaas <bjorn.helgaas@hp.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/console.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/serial_core.h>
+
+#ifdef CONFIG_FIX_EARLYCON_MEM
+#include <asm/fixmap.h>
+#endif
+
+#include <asm/serial.h>
+
+static struct console early_con = {
+	.name =		"earlycon",
+	.flags =	CON_PRINTBUFFER | CON_BOOT,
+	.index =	-1,
+};
+
+static struct earlycon_device early_console_dev = {
+	.con = &early_con,
+};
+
+static void __iomem * __init earlycon_map(unsigned long paddr, size_t size)
+{
+	void __iomem *base;
+#ifdef CONFIG_FIX_EARLYCON_MEM
+	set_fixmap_io(FIX_EARLYCON_MEM_BASE, paddr & PAGE_MASK);
+	base = (void __iomem *)__fix_to_virt(FIX_EARLYCON_MEM_BASE);
+	base += paddr & ~PAGE_MASK;
+#else
+	base = ioremap(paddr, size);
+#endif
+	if (!base)
+		pr_err("%s: Couldn't map 0x%llx\n", __func__,
+		       (unsigned long long)paddr);
+
+	return base;
+}
+
+static int __init parse_options(struct earlycon_device *device,
+				char *options)
+{
+	struct uart_port *port = &device->port;
+	int mmio, mmio32, length, ret;
+	unsigned long addr;
+
+	if (!options)
+		return -ENODEV;
+
+	mmio = !strncmp(options, "mmio,", 5);
+	mmio32 = !strncmp(options, "mmio32,", 7);
+	if (mmio || mmio32) {
+		port->iotype = (mmio ? UPIO_MEM : UPIO_MEM32);
+		options += mmio ? 5 : 7;
+		ret = kstrtoul(options, 0, &addr);
+		if (ret)
+			return ret;
+		port->mapbase = addr;
+		if (mmio32)
+			port->regshift = 2;
+	} else if (!strncmp(options, "io,", 3)) {
+		port->iotype = UPIO_PORT;
+		options += 3;
+		ret = kstrtoul(options, 0, &addr);
+		if (ret)
+			return ret;
+		port->iobase = addr;
+		mmio = 0;
+	} else if (!strncmp(options, "0x", 2)) {
+		port->iotype = UPIO_MEM;
+		ret = kstrtoul(options, 0, &addr);
+		if (ret)
+			return ret;
+		port->mapbase = addr;
+	} else {
+		return -EINVAL;
+	}
+
+	port->uartclk = BASE_BAUD * 16;
+
+	options = strchr(options, ',');
+	if (options) {
+		options++;
+		ret = kstrtouint(options, 0, &device->baud);
+		if (ret)
+			return ret;
+		length = min(strcspn(options, " ") + 1,
+			     (size_t)(sizeof(device->options)));
+		strlcpy(device->options, options, length);
+	}
+
+	if (mmio || mmio32)
+		pr_info("Early serial console at MMIO%s 0x%llx (options '%s')\n",
+			mmio32 ? "32" : "",
+			(unsigned long long)port->mapbase,
+			device->options);
+	else
+		pr_info("Early serial console at I/O port 0x%lx (options '%s')\n",
+			port->iobase,
+			device->options);
+
+	return 0;
+}
+
+int __init setup_earlycon(char *buf, const char *match,
+			  int (*setup)(struct earlycon_device *, const char *))
+{
+	int err;
+	size_t len;
+	struct uart_port *port = &early_console_dev.port;
+
+	if (!buf || !match || !setup)
+		return 0;
+
+	len = strlen(match);
+	if (strncmp(buf, match, len))
+		return 0;
+	if (buf[len] && (buf[len] != ','))
+		return 0;
+
+	buf += len + 1;
+
+	err = parse_options(&early_console_dev, buf);
+	/* On parsing error, pass the options buf to the setup function */
+	if (!err)
+		buf = NULL;
+
+	if (port->mapbase)
+		port->membase = earlycon_map(port->mapbase, 64);
+
+	early_console_dev.con->data = &early_console_dev;
+	err = setup(&early_console_dev, buf);
+	if (err < 0)
+		return err;
+	if (!early_console_dev.con->write)
+		return -ENODEV;
+
+	register_console(early_console_dev.con);
+	return 0;
+}
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index f729be9..7a15b5b 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -285,6 +285,22 @@ static inline int uart_poll_timeout(struct uart_port *port)
 /*
  * Console helpers.
  */
+struct earlycon_device {
+	struct console *con;
+	struct uart_port port;
+	char options[16];		/* e.g., 115200n8 */
+	unsigned int baud;
+};
+int setup_earlycon(char *buf, const char *match,
+		   int (*setup)(struct earlycon_device *, const char *));
+
+#define EARLYCON_DECLARE(name, func) \
+static int __init name ## _setup_earlycon(char *buf) \
+{ \
+	return setup_earlycon(buf, __stringify(name), func); \
+} \
+early_param("earlycon", name ## _setup_earlycon);
+
 struct uart_port *uart_get_console(struct uart_port *ports, int nr,
 				   struct console *c);
 void uart_parse_options(char *options, int *baud, int *parity, int *bits,
-- 
1.9.1

[PATCH v2 2/7] tty/serial: add generic serial earlycon

[Rob Herring]

From: Rob Herring <robh@kernel.org>

This introduces generic earlycon infrastructure for serial devices
based on the 8250 earlycon. This allows for supporting earlycon option
with other serial devices. The earlycon output is enabled at the time
early_params are processed.

Only architectures that have fixmap support or have functional ioremap
when early_params are processed are supported. This is the same
restriction that the 8250 driver had.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
---
v2:
- Use set_fixmap_io/ioremap instead of set_fixmap_nocache/ioremap_nocache.
- Do the mapping outside of option parsing function.
  
 drivers/tty/serial/Kconfig    |   7 ++
 drivers/tty/serial/Makefile   |   2 +
 drivers/tty/serial/earlycon.c | 152 ++++++++++++++++++++++++++++++++++++++++++
 include/linux/serial_core.h   |  16 +++++
 4 files changed, 177 insertions(+)
 create mode 100644 drivers/tty/serial/earlycon.c

diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 2e6d8dd..3b7c19b 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -7,6 +7,13 @@ if TTY
 menu "Serial drivers"
 	depends on HAS_IOMEM
 
+config SERIAL_EARLYCON
+	bool
+	help
+	  Support for early consoles with the earlycon parameter. This enables
+	  the console before standard serial driver is probed. The console is
+	  enabled when early_param is processed.
+
 source "drivers/tty/serial/8250/Kconfig"
 
 comment "Non-8250 serial port support"
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index 3680854..8af1415 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -5,6 +5,8 @@
 obj-$(CONFIG_SERIAL_CORE) += serial_core.o
 obj-$(CONFIG_SERIAL_21285) += 21285.o
 
+obj-$(CONFIG_SERIAL_EARLYCON) += earlycon.o
+
 # These Sparc drivers have to appear before others such as 8250
 # which share ttySx minor node space.  Otherwise console device
 # names change and other unplesantries.
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
new file mode 100644
index 0000000..73bf1e2
--- /dev/null
+++ b/drivers/tty/serial/earlycon.c
@@ -0,0 +1,152 @@
+/*
+ * Copyright (C) 2014 Linaro Ltd.
+ * Author: Rob Herring <robh@kernel.org>
+ *
+ * Based on 8250 earlycon:
+ * (c) Copyright 2004 Hewlett-Packard Development Company, L.P.
+ *	Bjorn Helgaas <bjorn.helgaas@hp.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/console.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/serial_core.h>
+
+#ifdef CONFIG_FIX_EARLYCON_MEM
+#include <asm/fixmap.h>
+#endif
+
+#include <asm/serial.h>
+
+static struct console early_con = {
+	.name =		"earlycon",
+	.flags =	CON_PRINTBUFFER | CON_BOOT,
+	.index =	-1,
+};
+
+static struct earlycon_device early_console_dev = {
+	.con = &early_con,
+};
+
+static void __iomem * __init earlycon_map(unsigned long paddr, size_t size)
+{
+	void __iomem *base;
+#ifdef CONFIG_FIX_EARLYCON_MEM
+	set_fixmap_io(FIX_EARLYCON_MEM_BASE, paddr & PAGE_MASK);
+	base = (void __iomem *)__fix_to_virt(FIX_EARLYCON_MEM_BASE);
+	base += paddr & ~PAGE_MASK;
+#else
+	base = ioremap(paddr, size);
+#endif
+	if (!base)
+		pr_err("%s: Couldn't map 0x%llx\n", __func__,
+		       (unsigned long long)paddr);
+
+	return base;
+}
+
+static int __init parse_options(struct earlycon_device *device,
+				char *options)
+{
+	struct uart_port *port = &device->port;
+	int mmio, mmio32, length, ret;
+	unsigned long addr;
+
+	if (!options)
+		return -ENODEV;
+
+	mmio = !strncmp(options, "mmio,", 5);
+	mmio32 = !strncmp(options, "mmio32,", 7);
+	if (mmio || mmio32) {
+		port->iotype = (mmio ? UPIO_MEM : UPIO_MEM32);
+		options += mmio ? 5 : 7;
+		ret = kstrtoul(options, 0, &addr);
+		if (ret)
+			return ret;
+		port->mapbase = addr;
+		if (mmio32)
+			port->regshift = 2;
+	} else if (!strncmp(options, "io,", 3)) {
+		port->iotype = UPIO_PORT;
+		options += 3;
+		ret = kstrtoul(options, 0, &addr);
+		if (ret)
+			return ret;
+		port->iobase = addr;
+		mmio = 0;
+	} else if (!strncmp(options, "0x", 2)) {
+		port->iotype = UPIO_MEM;
+		ret = kstrtoul(options, 0, &addr);
+		if (ret)
+			return ret;
+		port->mapbase = addr;
+	} else {
+		return -EINVAL;
+	}
+
+	port->uartclk = BASE_BAUD * 16;
+
+	options = strchr(options, ',');
+	if (options) {
+		options++;
+		ret = kstrtouint(options, 0, &device->baud);
+		if (ret)
+			return ret;
+		length = min(strcspn(options, " ") + 1,
+			     (size_t)(sizeof(device->options)));
+		strlcpy(device->options, options, length);
+	}
+
+	if (mmio || mmio32)
+		pr_info("Early serial console at MMIO%s 0x%llx (options '%s')\n",
+			mmio32 ? "32" : "",
+			(unsigned long long)port->mapbase,
+			device->options);
+	else
+		pr_info("Early serial console at I/O port 0x%lx (options '%s')\n",
+			port->iobase,
+			device->options);
+
+	return 0;
+}
+
+int __init setup_earlycon(char *buf, const char *match,
+			  int (*setup)(struct earlycon_device *, const char *))
+{
+	int err;
+	size_t len;
+	struct uart_port *port = &early_console_dev.port;
+
+	if (!buf || !match || !setup)
+		return 0;
+
+	len = strlen(match);
+	if (strncmp(buf, match, len))
+		return 0;
+	if (buf[len] && (buf[len] != ','))
+		return 0;
+
+	buf += len + 1;
+
+	err = parse_options(&early_console_dev, buf);
+	/* On parsing error, pass the options buf to the setup function */
+	if (!err)
+		buf = NULL;
+
+	if (port->mapbase)
+		port->membase = earlycon_map(port->mapbase, 64);
+
+	early_console_dev.con->data = &early_console_dev;
+	err = setup(&early_console_dev, buf);
+	if (err < 0)
+		return err;
+	if (!early_console_dev.con->write)
+		return -ENODEV;
+
+	register_console(early_console_dev.con);
+	return 0;
+}
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index f729be9..7a15b5b 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -285,6 +285,22 @@ static inline int uart_poll_timeout(struct uart_port *port)
 /*
  * Console helpers.
  */
+struct earlycon_device {
+	struct console *con;
+	struct uart_port port;
+	char options[16];		/* e.g., 115200n8 */
+	unsigned int baud;
+};
+int setup_earlycon(char *buf, const char *match,
+		   int (*setup)(struct earlycon_device *, const char *));
+
+#define EARLYCON_DECLARE(name, func) \
+static int __init name ## _setup_earlycon(char *buf) \
+{ \
+	return setup_earlycon(buf, __stringify(name), func); \
+} \
+early_param("earlycon", name ## _setup_earlycon);
+
 struct uart_port *uart_get_console(struct uart_port *ports, int nr,
 				   struct console *c);
 void uart_parse_options(char *options, int *baud, int *parity, int *bits,
-- 
1.9.1

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

From: Rob Herring <robh@kernel.org>

With the generic earlycon infrastructure in place, convert the 8250
early console to use it.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
---
 drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
 drivers/tty/serial/8250/Kconfig      |   1 +
 2 files changed, 16 insertions(+), 123 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
index c100d63..e83c9db 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -35,18 +35,8 @@
 #include <linux/serial_8250.h>
 #include <asm/io.h>
 #include <asm/serial.h>
-#ifdef CONFIG_FIX_EARLYCON_MEM
-#include <asm/pgtable.h>
-#include <asm/fixmap.h>
-#endif
 
-struct early_serial8250_device {
-	struct uart_port port;
-	char options[16];		/* e.g., 115200n8 */
-	unsigned int baud;
-};
-
-static struct early_serial8250_device early_device;
+static struct earlycon_device *early_device;
 
 unsigned int __weak __init serial8250_early_in(struct uart_port *port, int offset)
 {
@@ -100,7 +90,7 @@ static void __init serial_putc(struct uart_port *port, int c)
 static void __init early_serial8250_write(struct console *console,
 					const char *s, unsigned int count)
 {
-	struct uart_port *port = &early_device.port;
+	struct uart_port *port = &early_device->port;
 	unsigned int ier;
 
 	/* Save the IER and disable interrupts */
@@ -129,7 +119,7 @@ static unsigned int __init probe_baud(struct uart_port *port)
 	return (port->uartclk / 16) / quot;
 }
 
-static void __init init_port(struct early_serial8250_device *device)
+static void __init init_port(struct earlycon_device *device)
 {
 	struct uart_port *port = &device->port;
 	unsigned int divisor;
@@ -148,128 +138,32 @@ static void __init init_port(struct early_serial8250_device *device)
 	serial8250_early_out(port, UART_LCR, c & ~UART_LCR_DLAB);
 }
 
-static int __init parse_options(struct early_serial8250_device *device,
-								char *options)
-{
-	struct uart_port *port = &device->port;
-	int mmio, mmio32, length;
-
-	if (!options)
-		return -ENODEV;
-
-	port->uartclk = BASE_BAUD * 16;
-
-	mmio = !strncmp(options, "mmio,", 5);
-	mmio32 = !strncmp(options, "mmio32,", 7);
-	if (mmio || mmio32) {
-		port->iotype = (mmio ? UPIO_MEM : UPIO_MEM32);
-		port->mapbase = simple_strtoul(options + (mmio ? 5 : 7),
-					       &options, 0);
-		if (mmio32)
-			port->regshift = 2;
-#ifdef CONFIG_FIX_EARLYCON_MEM
-		set_fixmap_nocache(FIX_EARLYCON_MEM_BASE,
-					port->mapbase & PAGE_MASK);
-		port->membase =
-			(void __iomem *)__fix_to_virt(FIX_EARLYCON_MEM_BASE);
-		port->membase += port->mapbase & ~PAGE_MASK;
-#else
-		port->membase = ioremap_nocache(port->mapbase, 64);
-		if (!port->membase) {
-			printk(KERN_ERR "%s: Couldn't ioremap 0x%llx\n",
-				__func__,
-			       (unsigned long long) port->mapbase);
-			return -ENOMEM;
-		}
-#endif
-	} else if (!strncmp(options, "io,", 3)) {
-		port->iotype = UPIO_PORT;
-		port->iobase = simple_strtoul(options + 3, &options, 0);
-		mmio = 0;
-	} else
-		return -EINVAL;
-
-	options = strchr(options, ',');
-	if (options) {
-		options++;
-		device->baud = simple_strtoul(options, NULL, 0);
-		length = min(strcspn(options, " ") + 1,
-			     (size_t)(sizeof(device->options)));
-		strlcpy(device->options, options, length);
-	} else {
-		device->baud = probe_baud(port);
-		snprintf(device->options, sizeof(device->options), "%u",
-			device->baud);
-	}
-
-	if (mmio || mmio32)
-		printk(KERN_INFO
-		       "Early serial console at MMIO%s 0x%llx (options '%s')\n",
-			mmio32 ? "32" : "",
-			(unsigned long long)port->mapbase,
-			device->options);
-	else
-		printk(KERN_INFO
-		      "Early serial console at I/O port 0x%lx (options '%s')\n",
-			port->iobase,
-			device->options);
-
-	return 0;
-}
-
-static struct console early_serial8250_console __initdata = {
-	.name	= "uart",
-	.write	= early_serial8250_write,
-	.flags	= CON_PRINTBUFFER | CON_BOOT,
-	.index	= -1,
-};
-
-static int __init early_serial8250_setup(char *options)
+static int __init early_serial8250_setup(struct earlycon_device *device,
+					 const char *options)
 {
-	struct early_serial8250_device *device = &early_device;
-	int err;
-
-	if (device->port.membase || device->port.iobase)
+	if (!(device->port.membase || device->port.iobase))
 		return 0;
 
-	err = parse_options(device, options);
-	if (err < 0)
-		return err;
+	if (!device->baud)
+		device->baud = probe_baud(&device->port);
 
 	init_port(device);
-	return 0;
-}
-
-int __init setup_early_serial8250_console(char *cmdline)
-{
-	char *options;
-	int err;
-
-	options = strstr(cmdline, "uart8250,");
-	if (!options) {
-		options = strstr(cmdline, "uart,");
-		if (!options)
-			return 0;
-	}
-
-	options = strchr(cmdline, ',') + 1;
-	err = early_serial8250_setup(options);
-	if (err < 0)
-		return err;
-
-	register_console(&early_serial8250_console);
 
+	early_device = device;
+	device->con->write = early_serial8250_write;
 	return 0;
 }
+EARLYCON_DECLARE(uart8250, early_serial8250_setup);
+EARLYCON_DECLARE(uart, early_serial8250_setup);
 
 int serial8250_find_port_for_earlycon(void)
 {
-	struct early_serial8250_device *device = &early_device;
-	struct uart_port *port = &device->port;
+	struct earlycon_device *device = early_device;
+	struct uart_port *port = device ? &device->port : NULL;
 	int line;
 	int ret;
 
-	if (!device->port.membase && !device->port.iobase)
+	if (!port || (!port->membase && !port->iobase))
 		return -ENODEV;
 
 	line = serial8250_find_port(port);
@@ -284,5 +178,3 @@ int serial8250_find_port_for_earlycon(void)
 
 	return ret;
 }
-
-early_param("earlycon", setup_early_serial8250_console);
diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig
index 91f1d83..349ee59 100644
--- a/drivers/tty/serial/8250/Kconfig
+++ b/drivers/tty/serial/8250/Kconfig
@@ -61,6 +61,7 @@ config SERIAL_8250_CONSOLE
 	bool "Console on 8250/16550 and compatible serial port"
 	depends on SERIAL_8250=y
 	select SERIAL_CORE_CONSOLE
+	select SERIAL_EARLYCON
 	---help---
 	  If you say Y here, it will be possible to use a serial port as the
 	  system console (the system console is the device which receives all
-- 
1.9.1

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

From: Rob Herring <robh@kernel.org>

With the generic earlycon infrastructure in place, convert the 8250
early console to use it.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
---
 drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
 drivers/tty/serial/8250/Kconfig      |   1 +
 2 files changed, 16 insertions(+), 123 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
index c100d63..e83c9db 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -35,18 +35,8 @@
 #include <linux/serial_8250.h>
 #include <asm/io.h>
 #include <asm/serial.h>
-#ifdef CONFIG_FIX_EARLYCON_MEM
-#include <asm/pgtable.h>
-#include <asm/fixmap.h>
-#endif
 
-struct early_serial8250_device {
-	struct uart_port port;
-	char options[16];		/* e.g., 115200n8 */
-	unsigned int baud;
-};
-
-static struct early_serial8250_device early_device;
+static struct earlycon_device *early_device;
 
 unsigned int __weak __init serial8250_early_in(struct uart_port *port, int offset)
 {
@@ -100,7 +90,7 @@ static void __init serial_putc(struct uart_port *port, int c)
 static void __init early_serial8250_write(struct console *console,
 					const char *s, unsigned int count)
 {
-	struct uart_port *port = &early_device.port;
+	struct uart_port *port = &early_device->port;
 	unsigned int ier;
 
 	/* Save the IER and disable interrupts */
@@ -129,7 +119,7 @@ static unsigned int __init probe_baud(struct uart_port *port)
 	return (port->uartclk / 16) / quot;
 }
 
-static void __init init_port(struct early_serial8250_device *device)
+static void __init init_port(struct earlycon_device *device)
 {
 	struct uart_port *port = &device->port;
 	unsigned int divisor;
@@ -148,128 +138,32 @@ static void __init init_port(struct early_serial8250_device *device)
 	serial8250_early_out(port, UART_LCR, c & ~UART_LCR_DLAB);
 }
 
-static int __init parse_options(struct early_serial8250_device *device,
-								char *options)
-{
-	struct uart_port *port = &device->port;
-	int mmio, mmio32, length;
-
-	if (!options)
-		return -ENODEV;
-
-	port->uartclk = BASE_BAUD * 16;
-
-	mmio = !strncmp(options, "mmio,", 5);
-	mmio32 = !strncmp(options, "mmio32,", 7);
-	if (mmio || mmio32) {
-		port->iotype = (mmio ? UPIO_MEM : UPIO_MEM32);
-		port->mapbase = simple_strtoul(options + (mmio ? 5 : 7),
-					       &options, 0);
-		if (mmio32)
-			port->regshift = 2;
-#ifdef CONFIG_FIX_EARLYCON_MEM
-		set_fixmap_nocache(FIX_EARLYCON_MEM_BASE,
-					port->mapbase & PAGE_MASK);
-		port->membase =
-			(void __iomem *)__fix_to_virt(FIX_EARLYCON_MEM_BASE);
-		port->membase += port->mapbase & ~PAGE_MASK;
-#else
-		port->membase = ioremap_nocache(port->mapbase, 64);
-		if (!port->membase) {
-			printk(KERN_ERR "%s: Couldn't ioremap 0x%llx\n",
-				__func__,
-			       (unsigned long long) port->mapbase);
-			return -ENOMEM;
-		}
-#endif
-	} else if (!strncmp(options, "io,", 3)) {
-		port->iotype = UPIO_PORT;
-		port->iobase = simple_strtoul(options + 3, &options, 0);
-		mmio = 0;
-	} else
-		return -EINVAL;
-
-	options = strchr(options, ',');
-	if (options) {
-		options++;
-		device->baud = simple_strtoul(options, NULL, 0);
-		length = min(strcspn(options, " ") + 1,
-			     (size_t)(sizeof(device->options)));
-		strlcpy(device->options, options, length);
-	} else {
-		device->baud = probe_baud(port);
-		snprintf(device->options, sizeof(device->options), "%u",
-			device->baud);
-	}
-
-	if (mmio || mmio32)
-		printk(KERN_INFO
-		       "Early serial console at MMIO%s 0x%llx (options '%s')\n",
-			mmio32 ? "32" : "",
-			(unsigned long long)port->mapbase,
-			device->options);
-	else
-		printk(KERN_INFO
-		      "Early serial console at I/O port 0x%lx (options '%s')\n",
-			port->iobase,
-			device->options);
-
-	return 0;
-}
-
-static struct console early_serial8250_console __initdata = {
-	.name	= "uart",
-	.write	= early_serial8250_write,
-	.flags	= CON_PRINTBUFFER | CON_BOOT,
-	.index	= -1,
-};
-
-static int __init early_serial8250_setup(char *options)
+static int __init early_serial8250_setup(struct earlycon_device *device,
+					 const char *options)
 {
-	struct early_serial8250_device *device = &early_device;
-	int err;
-
-	if (device->port.membase || device->port.iobase)
+	if (!(device->port.membase || device->port.iobase))
 		return 0;
 
-	err = parse_options(device, options);
-	if (err < 0)
-		return err;
+	if (!device->baud)
+		device->baud = probe_baud(&device->port);
 
 	init_port(device);
-	return 0;
-}
-
-int __init setup_early_serial8250_console(char *cmdline)
-{
-	char *options;
-	int err;
-
-	options = strstr(cmdline, "uart8250,");
-	if (!options) {
-		options = strstr(cmdline, "uart,");
-		if (!options)
-			return 0;
-	}
-
-	options = strchr(cmdline, ',') + 1;
-	err = early_serial8250_setup(options);
-	if (err < 0)
-		return err;
-
-	register_console(&early_serial8250_console);
 
+	early_device = device;
+	device->con->write = early_serial8250_write;
 	return 0;
 }
+EARLYCON_DECLARE(uart8250, early_serial8250_setup);
+EARLYCON_DECLARE(uart, early_serial8250_setup);
 
 int serial8250_find_port_for_earlycon(void)
 {
-	struct early_serial8250_device *device = &early_device;
-	struct uart_port *port = &device->port;
+	struct earlycon_device *device = early_device;
+	struct uart_port *port = device ? &device->port : NULL;
 	int line;
 	int ret;
 
-	if (!device->port.membase && !device->port.iobase)
+	if (!port || (!port->membase && !port->iobase))
 		return -ENODEV;
 
 	line = serial8250_find_port(port);
@@ -284,5 +178,3 @@ int serial8250_find_port_for_earlycon(void)
 
 	return ret;
 }
-
-early_param("earlycon", setup_early_serial8250_console);
diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig
index 91f1d83..349ee59 100644
--- a/drivers/tty/serial/8250/Kconfig
+++ b/drivers/tty/serial/8250/Kconfig
@@ -61,6 +61,7 @@ config SERIAL_8250_CONSOLE
 	bool "Console on 8250/16550 and compatible serial port"
 	depends on SERIAL_8250=y
 	select SERIAL_CORE_CONSOLE
+	select SERIAL_EARLYCON
 	---help---
 	  If you say Y here, it will be possible to use a serial port as the
 	  system console (the system console is the device which receives all
-- 
1.9.1

[PATCH v2 4/7] tty/serial: pl011: add generic earlycon support

[Rob Herring]

From: Rob Herring <robh@kernel.org>

Add earlycon support for the pl011 serial port. This allows enabling
the pl011 for console when early_params are processed. This is based
on the arm64 earlyprintk support and is intended to replace it.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
---
v2:
- Rework the kernel-parameters.txt description

 Documentation/kernel-parameters.txt |  7 +++++++
 drivers/tty/serial/Kconfig          |  1 +
 drivers/tty/serial/amba-pl011.c     | 30 +++++++++++++++++++++++++++++-
 3 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 03e50b4..15b5fcca 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -890,6 +890,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			which are not unmapped.
 
 	earlycon=	[KNL] Output early console device and options.
+
 		uart[8250],io,<addr>[,options]
 		uart[8250],mmio,<addr>[,options]
 		uart[8250],mmio32,<addr>[,options]
@@ -899,6 +900,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			(mmio) or 32-bit (mmio32).
 			The options are the same as for ttyS, above.
 
+		pl011,<addr>
+			Start an early, polled-mode console on a pl011 serial
+			port at the specified address. The pl011 serial port
+			must already be setup and configured. Options are not
+			yet supported.
+
 	earlyprintk=	[X86,SH,BLACKFIN,ARM]
 			earlyprintk=vga
 			earlyprintk=efi
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 3b7c19b..b1b23c2 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -60,6 +60,7 @@ config SERIAL_AMBA_PL011_CONSOLE
 	bool "Support for console on AMBA serial port"
 	depends on SERIAL_AMBA_PL011=y
 	select SERIAL_CORE_CONSOLE
+	select SERIAL_EARLYCON
 	---help---
 	  Say Y here if you wish to use an AMBA PrimeCell UART as the system
 	  console (the system console is the device which receives all kernel
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index d4eda24..4227c0a 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -303,7 +303,7 @@ static void pl011_dma_probe_initcall(struct device *dev, struct uart_amba_port *
 
 	/* Optionally make use of an RX channel as well */
 	chan = dma_request_slave_channel(dev, "rx");
-	
+
 	if (!chan && plat->dma_rx_param) {
 		chan = dma_request_channel(mask, plat->dma_filter, plat->dma_rx_param);
 
@@ -2045,6 +2045,34 @@ static struct console amba_console = {
 };
 
 #define AMBA_CONSOLE	(&amba_console)
+
+static void pl011_putc(struct uart_port *port, int c)
+{
+	while (readl(port->membase + UART01x_FR) & UART01x_FR_TXFF)
+		;
+	writeb(c, port->membase + UART01x_DR);
+	while (readl(port->membase + UART01x_FR) & UART01x_FR_BUSY)
+		;
+}
+
+static void pl011_early_write(struct console *con, const char *s, unsigned n)
+{
+	struct earlycon_device *dev = con->data;
+
+	uart_console_write(&dev->port, s, n, pl011_putc);
+}
+
+static int __init pl011_early_console_setup(struct earlycon_device *device,
+					    const char *opt)
+{
+	if (!device->port.membase)
+		return -ENODEV;
+
+	device->con->write = pl011_early_write;
+	return 0;
+}
+EARLYCON_DECLARE(pl011, pl011_early_console_setup);
+
 #else
 #define AMBA_CONSOLE	NULL
 #endif
-- 
1.9.1

[PATCH v2 4/7] tty/serial: pl011: add generic earlycon support

[Rob Herring]

From: Rob Herring <robh@kernel.org>

Add earlycon support for the pl011 serial port. This allows enabling
the pl011 for console when early_params are processed. This is based
on the arm64 earlyprintk support and is intended to replace it.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
---
v2:
- Rework the kernel-parameters.txt description

 Documentation/kernel-parameters.txt |  7 +++++++
 drivers/tty/serial/Kconfig          |  1 +
 drivers/tty/serial/amba-pl011.c     | 30 +++++++++++++++++++++++++++++-
 3 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 03e50b4..15b5fcca 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -890,6 +890,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			which are not unmapped.
 
 	earlycon=	[KNL] Output early console device and options.
+
 		uart[8250],io,<addr>[,options]
 		uart[8250],mmio,<addr>[,options]
 		uart[8250],mmio32,<addr>[,options]
@@ -899,6 +900,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			(mmio) or 32-bit (mmio32).
 			The options are the same as for ttyS, above.
 
+		pl011,<addr>
+			Start an early, polled-mode console on a pl011 serial
+			port at the specified address. The pl011 serial port
+			must already be setup and configured. Options are not
+			yet supported.
+
 	earlyprintk=	[X86,SH,BLACKFIN,ARM]
 			earlyprintk=vga
 			earlyprintk=efi
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 3b7c19b..b1b23c2 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -60,6 +60,7 @@ config SERIAL_AMBA_PL011_CONSOLE
 	bool "Support for console on AMBA serial port"
 	depends on SERIAL_AMBA_PL011=y
 	select SERIAL_CORE_CONSOLE
+	select SERIAL_EARLYCON
 	---help---
 	  Say Y here if you wish to use an AMBA PrimeCell UART as the system
 	  console (the system console is the device which receives all kernel
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index d4eda24..4227c0a 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -303,7 +303,7 @@ static void pl011_dma_probe_initcall(struct device *dev, struct uart_amba_port *
 
 	/* Optionally make use of an RX channel as well */
 	chan = dma_request_slave_channel(dev, "rx");
-	
+
 	if (!chan && plat->dma_rx_param) {
 		chan = dma_request_channel(mask, plat->dma_filter, plat->dma_rx_param);
 
@@ -2045,6 +2045,34 @@ static struct console amba_console = {
 };
 
 #define AMBA_CONSOLE	(&amba_console)
+
+static void pl011_putc(struct uart_port *port, int c)
+{
+	while (readl(port->membase + UART01x_FR) & UART01x_FR_TXFF)
+		;
+	writeb(c, port->membase + UART01x_DR);
+	while (readl(port->membase + UART01x_FR) & UART01x_FR_BUSY)
+		;
+}
+
+static void pl011_early_write(struct console *con, const char *s, unsigned n)
+{
+	struct earlycon_device *dev = con->data;
+
+	uart_console_write(&dev->port, s, n, pl011_putc);
+}
+
+static int __init pl011_early_console_setup(struct earlycon_device *device,
+					    const char *opt)
+{
+	if (!device->port.membase)
+		return -ENODEV;
+
+	device->con->write = pl011_early_write;
+	return 0;
+}
+EARLYCON_DECLARE(pl011, pl011_early_console_setup);
+
 #else
 #define AMBA_CONSOLE	NULL
 #endif
-- 
1.9.1

[PATCH v2 5/7] tty/serial: add arm/arm64 semihosting earlycon

[Rob Herring]

From: Rob Herring <robh@kernel.org>

Add earlycon support for the arm/arm64 semihosting debug serial
interface. This allows enabling a debug console when early_params are
processed. This is based on the arm64 earlyprintk smh support and is
intended to replace it.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
---
v2:
- Add support for ARM32 semihosting
- Rework the kernel-parameters.txt description
- Update copyright per Catalin.

 Documentation/kernel-parameters.txt        |  2 +
 drivers/tty/serial/Kconfig                 | 10 +++++
 drivers/tty/serial/Makefile                |  1 +
 drivers/tty/serial/earlycon-arm-semihost.c | 61 ++++++++++++++++++++++++++++++
 4 files changed, 74 insertions(+)
 create mode 100644 drivers/tty/serial/earlycon-arm-semihost.c

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 15b5fcca..9e9935a 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -906,6 +906,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			must already be setup and configured. Options are not
 			yet supported.
 
+		smh	Use ARM semihosting calls for early console.
+
 	earlyprintk=	[X86,SH,BLACKFIN,ARM]
 			earlyprintk=vga
 			earlyprintk=efi
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index b1b23c2..8cce654 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -73,6 +73,16 @@ config SERIAL_AMBA_PL011_CONSOLE
 	  your boot loader (lilo or loadlin) about how to pass options to the
 	  kernel at boot time.)
 
+config SERIAL_EARLYCON_ARM_SEMIHOST
+	bool "Early console using ARM semihosting"
+	depends on ARM64 || ARM
+	select SERIAL_EARLYCON
+	help
+	  Support for early debug console using ARM semihosting. This enables
+	  the console before standard serial driver is probed. This is enabled
+	  with "earlycon=smh" on the kernel command line. The console is
+	  enabled when early_param is processed.
+
 config SERIAL_SB1250_DUART
 	tristate "BCM1xxx on-chip DUART serial support"
 	depends on SIBYTE_SB1xxx_SOC=y
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index 8af1415..9965b65 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -6,6 +6,7 @@ obj-$(CONFIG_SERIAL_CORE) += serial_core.o
 obj-$(CONFIG_SERIAL_21285) += 21285.o
 
 obj-$(CONFIG_SERIAL_EARLYCON) += earlycon.o
+obj-$(CONFIG_SERIAL_EARLYCON_ARM_SEMIHOST) += earlycon-arm-semihost.o
 
 # These Sparc drivers have to appear before others such as 8250
 # which share ttySx minor node space.  Otherwise console device
diff --git a/drivers/tty/serial/earlycon-arm-semihost.c b/drivers/tty/serial/earlycon-arm-semihost.c
new file mode 100644
index 0000000..383db10
--- /dev/null
+++ b/drivers/tty/serial/earlycon-arm-semihost.c
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * Adapted for ARM and earlycon:
+ * Copyright (C) 2014 Linaro Ltd.
+ * Author: Rob Herring <robh@kernel.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/kernel.h>
+#include <linux/console.h>
+#include <linux/init.h>
+#include <linux/serial_core.h>
+
+#ifdef CONFIG_THUMB2_KERNEL
+#define SEMIHOST_SWI	"0xab"
+#else
+#define SEMIHOST_SWI	"0x123456"
+#endif
+
+/*
+ * Semihosting-based debug console
+ */
+static void smh_putc(struct uart_port *port, int c)
+{
+#ifdef CONFIG_ARM64
+	asm volatile("mov  x1, %0\n"
+		     "mov  x0, #3\n"
+		     "hlt  0xf000\n"
+		     : : "r" (&c) : "x0", "x1", "memory");
+#else
+	asm volatile("mov  r1, %0\n"
+		     "mov  r0, #3\n"
+		     "svc  " SEMIHOST_SWI "\n"
+		     : : "r" (&c) : "r0", "r1", "memory");
+#endif
+}
+
+static void smh_write(struct console *con, const char *s, unsigned n)
+{
+	struct earlycon_device *dev = con->data;
+	uart_console_write(&dev->port, s, n, smh_putc);
+}
+
+int __init early_smh_setup(struct earlycon_device *device, const char *opt)
+{
+	device->con->write = smh_write;
+	return 0;
+}
+EARLYCON_DECLARE(smh, early_smh_setup);
-- 
1.9.1

[PATCH v2 5/7] tty/serial: add arm/arm64 semihosting earlycon

[Rob Herring]

From: Rob Herring <robh@kernel.org>

Add earlycon support for the arm/arm64 semihosting debug serial
interface. This allows enabling a debug console when early_params are
processed. This is based on the arm64 earlyprintk smh support and is
intended to replace it.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
---
v2:
- Add support for ARM32 semihosting
- Rework the kernel-parameters.txt description
- Update copyright per Catalin.

 Documentation/kernel-parameters.txt        |  2 +
 drivers/tty/serial/Kconfig                 | 10 +++++
 drivers/tty/serial/Makefile                |  1 +
 drivers/tty/serial/earlycon-arm-semihost.c | 61 ++++++++++++++++++++++++++++++
 4 files changed, 74 insertions(+)
 create mode 100644 drivers/tty/serial/earlycon-arm-semihost.c

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 15b5fcca..9e9935a 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -906,6 +906,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			must already be setup and configured. Options are not
 			yet supported.
 
+		smh	Use ARM semihosting calls for early console.
+
 	earlyprintk=	[X86,SH,BLACKFIN,ARM]
 			earlyprintk=vga
 			earlyprintk=efi
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index b1b23c2..8cce654 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -73,6 +73,16 @@ config SERIAL_AMBA_PL011_CONSOLE
 	  your boot loader (lilo or loadlin) about how to pass options to the
 	  kernel at boot time.)
 
+config SERIAL_EARLYCON_ARM_SEMIHOST
+	bool "Early console using ARM semihosting"
+	depends on ARM64 || ARM
+	select SERIAL_EARLYCON
+	help
+	  Support for early debug console using ARM semihosting. This enables
+	  the console before standard serial driver is probed. This is enabled
+	  with "earlycon=smh" on the kernel command line. The console is
+	  enabled when early_param is processed.
+
 config SERIAL_SB1250_DUART
 	tristate "BCM1xxx on-chip DUART serial support"
 	depends on SIBYTE_SB1xxx_SOC=y
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index 8af1415..9965b65 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -6,6 +6,7 @@ obj-$(CONFIG_SERIAL_CORE) += serial_core.o
 obj-$(CONFIG_SERIAL_21285) += 21285.o
 
 obj-$(CONFIG_SERIAL_EARLYCON) += earlycon.o
+obj-$(CONFIG_SERIAL_EARLYCON_ARM_SEMIHOST) += earlycon-arm-semihost.o
 
 # These Sparc drivers have to appear before others such as 8250
 # which share ttySx minor node space.  Otherwise console device
diff --git a/drivers/tty/serial/earlycon-arm-semihost.c b/drivers/tty/serial/earlycon-arm-semihost.c
new file mode 100644
index 0000000..383db10
--- /dev/null
+++ b/drivers/tty/serial/earlycon-arm-semihost.c
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * Adapted for ARM and earlycon:
+ * Copyright (C) 2014 Linaro Ltd.
+ * Author: Rob Herring <robh@kernel.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/kernel.h>
+#include <linux/console.h>
+#include <linux/init.h>
+#include <linux/serial_core.h>
+
+#ifdef CONFIG_THUMB2_KERNEL
+#define SEMIHOST_SWI	"0xab"
+#else
+#define SEMIHOST_SWI	"0x123456"
+#endif
+
+/*
+ * Semihosting-based debug console
+ */
+static void smh_putc(struct uart_port *port, int c)
+{
+#ifdef CONFIG_ARM64
+	asm volatile("mov  x1, %0\n"
+		     "mov  x0, #3\n"
+		     "hlt  0xf000\n"
+		     : : "r" (&c) : "x0", "x1", "memory");
+#else
+	asm volatile("mov  r1, %0\n"
+		     "mov  r0, #3\n"
+		     "svc  " SEMIHOST_SWI "\n"
+		     : : "r" (&c) : "r0", "r1", "memory");
+#endif
+}
+
+static void smh_write(struct console *con, const char *s, unsigned n)
+{
+	struct earlycon_device *dev = con->data;
+	uart_console_write(&dev->port, s, n, smh_putc);
+}
+
+int __init early_smh_setup(struct earlycon_device *device, const char *opt)
+{
+	device->con->write = smh_write;
+	return 0;
+}
+EARLYCON_DECLARE(smh, early_smh_setup);
-- 
1.9.1

[PATCH v2 5/7] tty/serial: add arm/arm64 semihosting earlycon

[Rob Herring]

From: Rob Herring <robh@kernel.org>

Add earlycon support for the arm/arm64 semihosting debug serial
interface. This allows enabling a debug console when early_params are
processed. This is based on the arm64 earlyprintk smh support and is
intended to replace it.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
---
v2:
- Add support for ARM32 semihosting
- Rework the kernel-parameters.txt description
- Update copyright per Catalin.

 Documentation/kernel-parameters.txt        |  2 +
 drivers/tty/serial/Kconfig                 | 10 +++++
 drivers/tty/serial/Makefile                |  1 +
 drivers/tty/serial/earlycon-arm-semihost.c | 61 ++++++++++++++++++++++++++++++
 4 files changed, 74 insertions(+)
 create mode 100644 drivers/tty/serial/earlycon-arm-semihost.c

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 15b5fcca..9e9935a 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -906,6 +906,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			must already be setup and configured. Options are not
 			yet supported.
 
+		smh	Use ARM semihosting calls for early console.
+
 	earlyprintk=	[X86,SH,BLACKFIN,ARM]
 			earlyprintk=vga
 			earlyprintk=efi
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index b1b23c2..8cce654 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -73,6 +73,16 @@ config SERIAL_AMBA_PL011_CONSOLE
 	  your boot loader (lilo or loadlin) about how to pass options to the
 	  kernel at boot time.)
 
+config SERIAL_EARLYCON_ARM_SEMIHOST
+	bool "Early console using ARM semihosting"
+	depends on ARM64 || ARM
+	select SERIAL_EARLYCON
+	help
+	  Support for early debug console using ARM semihosting. This enables
+	  the console before standard serial driver is probed. This is enabled
+	  with "earlycon=smh" on the kernel command line. The console is
+	  enabled when early_param is processed.
+
 config SERIAL_SB1250_DUART
 	tristate "BCM1xxx on-chip DUART serial support"
 	depends on SIBYTE_SB1xxx_SOC=y
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index 8af1415..9965b65 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -6,6 +6,7 @@ obj-$(CONFIG_SERIAL_CORE) += serial_core.o
 obj-$(CONFIG_SERIAL_21285) += 21285.o
 
 obj-$(CONFIG_SERIAL_EARLYCON) += earlycon.o
+obj-$(CONFIG_SERIAL_EARLYCON_ARM_SEMIHOST) += earlycon-arm-semihost.o
 
 # These Sparc drivers have to appear before others such as 8250
 # which share ttySx minor node space.  Otherwise console device
diff --git a/drivers/tty/serial/earlycon-arm-semihost.c b/drivers/tty/serial/earlycon-arm-semihost.c
new file mode 100644
index 0000000..383db10
--- /dev/null
+++ b/drivers/tty/serial/earlycon-arm-semihost.c
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * Adapted for ARM and earlycon:
+ * Copyright (C) 2014 Linaro Ltd.
+ * Author: Rob Herring <robh@kernel.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/kernel.h>
+#include <linux/console.h>
+#include <linux/init.h>
+#include <linux/serial_core.h>
+
+#ifdef CONFIG_THUMB2_KERNEL
+#define SEMIHOST_SWI	"0xab"
+#else
+#define SEMIHOST_SWI	"0x123456"
+#endif
+
+/*
+ * Semihosting-based debug console
+ */
+static void smh_putc(struct uart_port *port, int c)
+{
+#ifdef CONFIG_ARM64
+	asm volatile("mov  x1, %0\n"
+		     "mov  x0, #3\n"
+		     "hlt  0xf000\n"
+		     : : "r" (&c) : "x0", "x1", "memory");
+#else
+	asm volatile("mov  r1, %0\n"
+		     "mov  r0, #3\n"
+		     "svc  " SEMIHOST_SWI "\n"
+		     : : "r" (&c) : "r0", "r1", "memory");
+#endif
+}
+
+static void smh_write(struct console *con, const char *s, unsigned n)
+{
+	struct earlycon_device *dev = con->data;
+	uart_console_write(&dev->port, s, n, smh_putc);
+}
+
+int __init early_smh_setup(struct earlycon_device *device, const char *opt)
+{
+	device->con->write = smh_write;
+	return 0;
+}
+EARLYCON_DECLARE(smh, early_smh_setup);
-- 
1.9.1

[PATCH v2 6/7] arm64: enable FIX_EARLYCON_MEM kconfig

[Rob Herring]

From: Rob Herring <robh@kernel.org>

In order to support earlycon on arm64, we need to enable earlycon fixmap
support.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
---
 arch/arm64/Kconfig | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index e6e4d37..22d1397 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -112,6 +112,9 @@ config IOMMU_HELPER
 config KERNEL_MODE_NEON
 	def_bool y
 
+config FIX_EARLYCON_MEM
+	def_bool y
+
 source "init/Kconfig"
 
 source "kernel/Kconfig.freezer"
-- 
1.9.1

[PATCH v2 6/7] arm64: enable FIX_EARLYCON_MEM kconfig

[Rob Herring]

From: Rob Herring <robh@kernel.org>

In order to support earlycon on arm64, we need to enable earlycon fixmap
support.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
---
 arch/arm64/Kconfig | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index e6e4d37..22d1397 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -112,6 +112,9 @@ config IOMMU_HELPER
 config KERNEL_MODE_NEON
 	def_bool y
 
+config FIX_EARLYCON_MEM
+	def_bool y
+
 source "init/Kconfig"
 
 source "kernel/Kconfig.freezer"
-- 
1.9.1

[PATCH v2 7/7] arm64: remove arch specific earlyprintk

[Rob Herring]

From: Rob Herring <robh@kernel.org>

Now that we have equivalent earlycon support, arm64's earlyprintk code
can be removed.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
---
 arch/arm64/Kconfig.debug         |   9 ---
 arch/arm64/kernel/Makefile       |   1 -
 arch/arm64/kernel/early_printk.c | 158 ---------------------------------------
 3 files changed, 168 deletions(-)
 delete mode 100644 arch/arm64/kernel/early_printk.c

diff --git a/arch/arm64/Kconfig.debug b/arch/arm64/Kconfig.debug
index d10ec33..1c1b756 100644
--- a/arch/arm64/Kconfig.debug
+++ b/arch/arm64/Kconfig.debug
@@ -20,15 +20,6 @@ config STRICT_DEVMEM
 
 	  If in doubt, say Y.
 
-config EARLY_PRINTK
-	bool "Early printk support"
-	default y
-	help
-	  Say Y here if you want to have an early console using the
-	  earlyprintk=<name>[,<addr>][,<options>] kernel parameter. It
-	  is assumed that the early console device has been initialised
-	  by the boot loader prior to starting the Linux kernel.
-
 config PID_IN_CONTEXTIDR
 	bool "Write the current PID to the CONTEXTIDR register"
 	help
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index 7d811d9..7a6fce5 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -18,7 +18,6 @@ arm64-obj-$(CONFIG_SMP)			+= smp.o smp_spin_table.o topology.o
 arm64-obj-$(CONFIG_PERF_EVENTS)		+= perf_regs.o
 arm64-obj-$(CONFIG_HW_PERF_EVENTS)	+= perf_event.o
 arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)	+= hw_breakpoint.o
-arm64-obj-$(CONFIG_EARLY_PRINTK)	+= early_printk.o
 arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND)	+= sleep.o suspend.o
 arm64-obj-$(CONFIG_JUMP_LABEL)		+= jump_label.o
 arm64-obj-$(CONFIG_KGDB)		+= kgdb.o
diff --git a/arch/arm64/kernel/early_printk.c b/arch/arm64/kernel/early_printk.c
deleted file mode 100644
index ffbbdde..0000000
--- a/arch/arm64/kernel/early_printk.c
+++ /dev/null
@@ -1,158 +0,0 @@
-/*
- * Earlyprintk support.
- *
- * Copyright (C) 2012 ARM Ltd.
- * Author: Catalin Marinas <catalin.marinas@arm.com>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-#include <linux/kernel.h>
-#include <linux/console.h>
-#include <linux/init.h>
-#include <linux/string.h>
-#include <linux/mm.h>
-#include <linux/io.h>
-
-#include <linux/amba/serial.h>
-#include <linux/serial_reg.h>
-
-#include <asm/fixmap.h>
-
-static void __iomem *early_base;
-static void (*printch)(char ch);
-
-/*
- * PL011 single character TX.
- */
-static void pl011_printch(char ch)
-{
-	while (readl_relaxed(early_base + UART01x_FR) & UART01x_FR_TXFF)
-		;
-	writeb_relaxed(ch, early_base + UART01x_DR);
-	while (readl_relaxed(early_base + UART01x_FR) & UART01x_FR_BUSY)
-		;
-}
-
-/*
- * Semihosting-based debug console
- */
-static void smh_printch(char ch)
-{
-	asm volatile("mov  x1, %0\n"
-		     "mov  x0, #3\n"
-		     "hlt  0xf000\n"
-		     : : "r" (&ch) : "x0", "x1", "memory");
-}
-
-/*
- * 8250/16550 (8-bit aligned registers) single character TX.
- */
-static void uart8250_8bit_printch(char ch)
-{
-	while (!(readb_relaxed(early_base + UART_LSR) & UART_LSR_THRE))
-		;
-	writeb_relaxed(ch, early_base + UART_TX);
-}
-
-/*
- * 8250/16550 (32-bit aligned registers) single character TX.
- */
-static void uart8250_32bit_printch(char ch)
-{
-	while (!(readl_relaxed(early_base + (UART_LSR << 2)) & UART_LSR_THRE))
-		;
-	writel_relaxed(ch, early_base + (UART_TX << 2));
-}
-
-struct earlycon_match {
-	const char *name;
-	void (*printch)(char ch);
-};
-
-static const struct earlycon_match earlycon_match[] __initconst = {
-	{ .name = "pl011", .printch = pl011_printch, },
-	{ .name = "smh", .printch = smh_printch, },
-	{ .name = "uart8250-8bit", .printch = uart8250_8bit_printch, },
-	{ .name = "uart8250-32bit", .printch = uart8250_32bit_printch, },
-	{}
-};
-
-static void early_write(struct console *con, const char *s, unsigned n)
-{
-	while (n-- > 0) {
-		if (*s == '\n')
-			printch('\r');
-		printch(*s);
-		s++;
-	}
-}
-
-static struct console early_console_dev = {
-	.name =		"earlycon",
-	.write =	early_write,
-	.flags =	CON_PRINTBUFFER | CON_BOOT,
-	.index =	-1,
-};
-
-/*
- * Parse earlyprintk=... parameter in the format:
- *
- *   <name>[,<addr>][,<options>]
- *
- * and register the early console. It is assumed that the UART has been
- * initialised by the bootloader already.
- */
-static int __init setup_early_printk(char *buf)
-{
-	const struct earlycon_match *match = earlycon_match;
-	phys_addr_t paddr = 0;
-
-	if (!buf) {
-		pr_warning("No earlyprintk arguments passed.\n");
-		return 0;
-	}
-
-	while (match->name) {
-		size_t len = strlen(match->name);
-		if (!strncmp(buf, match->name, len)) {
-			buf += len;
-			break;
-		}
-		match++;
-	}
-	if (!match->name) {
-		pr_warning("Unknown earlyprintk arguments: %s\n", buf);
-		return 0;
-	}
-
-	/* I/O address */
-	if (!strncmp(buf, ",0x", 3)) {
-		char *e;
-		paddr = simple_strtoul(buf + 1, &e, 16);
-		buf = e;
-	}
-	/* no options parsing yet */
-
-	if (paddr) {
-		set_fixmap_io(FIX_EARLYCON_MEM_BASE, paddr);
-		early_base = (void __iomem *)fix_to_virt(FIX_EARLYCON_MEM_BASE);
-	}
-
-	printch = match->printch;
-	early_console = &early_console_dev;
-	register_console(&early_console_dev);
-
-	return 0;
-}
-
-early_param("earlyprintk", setup_early_printk);
-- 
1.9.1

[PATCH v2 7/7] arm64: remove arch specific earlyprintk

[Rob Herring]

From: Rob Herring <robh@kernel.org>

Now that we have equivalent earlycon support, arm64's earlyprintk code
can be removed.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
---
 arch/arm64/Kconfig.debug         |   9 ---
 arch/arm64/kernel/Makefile       |   1 -
 arch/arm64/kernel/early_printk.c | 158 ---------------------------------------
 3 files changed, 168 deletions(-)
 delete mode 100644 arch/arm64/kernel/early_printk.c

diff --git a/arch/arm64/Kconfig.debug b/arch/arm64/Kconfig.debug
index d10ec33..1c1b756 100644
--- a/arch/arm64/Kconfig.debug
+++ b/arch/arm64/Kconfig.debug
@@ -20,15 +20,6 @@ config STRICT_DEVMEM
 
 	  If in doubt, say Y.
 
-config EARLY_PRINTK
-	bool "Early printk support"
-	default y
-	help
-	  Say Y here if you want to have an early console using the
-	  earlyprintk=<name>[,<addr>][,<options>] kernel parameter. It
-	  is assumed that the early console device has been initialised
-	  by the boot loader prior to starting the Linux kernel.
-
 config PID_IN_CONTEXTIDR
 	bool "Write the current PID to the CONTEXTIDR register"
 	help
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index 7d811d9..7a6fce5 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -18,7 +18,6 @@ arm64-obj-$(CONFIG_SMP)			+= smp.o smp_spin_table.o topology.o
 arm64-obj-$(CONFIG_PERF_EVENTS)		+= perf_regs.o
 arm64-obj-$(CONFIG_HW_PERF_EVENTS)	+= perf_event.o
 arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)	+= hw_breakpoint.o
-arm64-obj-$(CONFIG_EARLY_PRINTK)	+= early_printk.o
 arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND)	+= sleep.o suspend.o
 arm64-obj-$(CONFIG_JUMP_LABEL)		+= jump_label.o
 arm64-obj-$(CONFIG_KGDB)		+= kgdb.o
diff --git a/arch/arm64/kernel/early_printk.c b/arch/arm64/kernel/early_printk.c
deleted file mode 100644
index ffbbdde..0000000
--- a/arch/arm64/kernel/early_printk.c
+++ /dev/null
@@ -1,158 +0,0 @@
-/*
- * Earlyprintk support.
- *
- * Copyright (C) 2012 ARM Ltd.
- * Author: Catalin Marinas <catalin.marinas@arm.com>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-#include <linux/kernel.h>
-#include <linux/console.h>
-#include <linux/init.h>
-#include <linux/string.h>
-#include <linux/mm.h>
-#include <linux/io.h>
-
-#include <linux/amba/serial.h>
-#include <linux/serial_reg.h>
-
-#include <asm/fixmap.h>
-
-static void __iomem *early_base;
-static void (*printch)(char ch);
-
-/*
- * PL011 single character TX.
- */
-static void pl011_printch(char ch)
-{
-	while (readl_relaxed(early_base + UART01x_FR) & UART01x_FR_TXFF)
-		;
-	writeb_relaxed(ch, early_base + UART01x_DR);
-	while (readl_relaxed(early_base + UART01x_FR) & UART01x_FR_BUSY)
-		;
-}
-
-/*
- * Semihosting-based debug console
- */
-static void smh_printch(char ch)
-{
-	asm volatile("mov  x1, %0\n"
-		     "mov  x0, #3\n"
-		     "hlt  0xf000\n"
-		     : : "r" (&ch) : "x0", "x1", "memory");
-}
-
-/*
- * 8250/16550 (8-bit aligned registers) single character TX.
- */
-static void uart8250_8bit_printch(char ch)
-{
-	while (!(readb_relaxed(early_base + UART_LSR) & UART_LSR_THRE))
-		;
-	writeb_relaxed(ch, early_base + UART_TX);
-}
-
-/*
- * 8250/16550 (32-bit aligned registers) single character TX.
- */
-static void uart8250_32bit_printch(char ch)
-{
-	while (!(readl_relaxed(early_base + (UART_LSR << 2)) & UART_LSR_THRE))
-		;
-	writel_relaxed(ch, early_base + (UART_TX << 2));
-}
-
-struct earlycon_match {
-	const char *name;
-	void (*printch)(char ch);
-};
-
-static const struct earlycon_match earlycon_match[] __initconst = {
-	{ .name = "pl011", .printch = pl011_printch, },
-	{ .name = "smh", .printch = smh_printch, },
-	{ .name = "uart8250-8bit", .printch = uart8250_8bit_printch, },
-	{ .name = "uart8250-32bit", .printch = uart8250_32bit_printch, },
-	{}
-};
-
-static void early_write(struct console *con, const char *s, unsigned n)
-{
-	while (n-- > 0) {
-		if (*s == '\n')
-			printch('\r');
-		printch(*s);
-		s++;
-	}
-}
-
-static struct console early_console_dev = {
-	.name =		"earlycon",
-	.write =	early_write,
-	.flags =	CON_PRINTBUFFER | CON_BOOT,
-	.index =	-1,
-};
-
-/*
- * Parse earlyprintk=... parameter in the format:
- *
- *   <name>[,<addr>][,<options>]
- *
- * and register the early console. It is assumed that the UART has been
- * initialised by the bootloader already.
- */
-static int __init setup_early_printk(char *buf)
-{
-	const struct earlycon_match *match = earlycon_match;
-	phys_addr_t paddr = 0;
-
-	if (!buf) {
-		pr_warning("No earlyprintk arguments passed.\n");
-		return 0;
-	}
-
-	while (match->name) {
-		size_t len = strlen(match->name);
-		if (!strncmp(buf, match->name, len)) {
-			buf += len;
-			break;
-		}
-		match++;
-	}
-	if (!match->name) {
-		pr_warning("Unknown earlyprintk arguments: %s\n", buf);
-		return 0;
-	}
-
-	/* I/O address */
-	if (!strncmp(buf, ",0x", 3)) {
-		char *e;
-		paddr = simple_strtoul(buf + 1, &e, 16);
-		buf = e;
-	}
-	/* no options parsing yet */
-
-	if (paddr) {
-		set_fixmap_io(FIX_EARLYCON_MEM_BASE, paddr);
-		early_base = (void __iomem *)fix_to_virt(FIX_EARLYCON_MEM_BASE);
-	}
-
-	printch = match->printch;
-	early_console = &early_console_dev;
-	register_console(&early_console_dev);
-
-	return 0;
-}
-
-early_param("earlyprintk", setup_early_printk);
-- 
1.9.1

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
> From: Rob Herring <robh@kernel.org>
>
> With the generic earlycon infrastructure in place, convert the 8250
> early console to use it.
>
> Signed-off-by: Rob Herring <robh@kernel.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Jiri Slaby <jslaby@suse.cz>
> ---
>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>  drivers/tty/serial/8250/Kconfig      |   1 +
>  2 files changed, 16 insertions(+), 123 deletions(-)

Hi Greg, Rob

This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
No early console and regular console anymore.

It should produce "early con and regular con".

Thanks

Yinghai

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
> From: Rob Herring <robh@kernel.org>
>
> With the generic earlycon infrastructure in place, convert the 8250
> early console to use it.
>
> Signed-off-by: Rob Herring <robh@kernel.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Jiri Slaby <jslaby@suse.cz>
> ---
>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>  drivers/tty/serial/8250/Kconfig      |   1 +
>  2 files changed, 16 insertions(+), 123 deletions(-)

Hi Greg, Rob

This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
No early console and regular console anymore.

It should produce "early con and regular con".

Thanks

Yinghai

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
> From: Rob Herring <robh@kernel.org>
>
> With the generic earlycon infrastructure in place, convert the 8250
> early console to use it.
>
> Signed-off-by: Rob Herring <robh@kernel.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Jiri Slaby <jslaby@suse.cz>
> ---
>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>  drivers/tty/serial/8250/Kconfig      |   1 +
>  2 files changed, 16 insertions(+), 123 deletions(-)

Hi Greg, Rob

This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
No early console and regular console anymore.

It should produce "early con and regular con".

Thanks

Yinghai

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
> From: Rob Herring <robh@kernel.org>
>
> With the generic earlycon infrastructure in place, convert the 8250
> early console to use it.
>
> Signed-off-by: Rob Herring <robh@kernel.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Jiri Slaby <jslaby@suse.cz>
> ---
>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>  drivers/tty/serial/8250/Kconfig      |   1 +
>  2 files changed, 16 insertions(+), 123 deletions(-)
>
> diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
> index c100d63..e83c9db 100644
> --- a/drivers/tty/serial/8250/8250_early.c
> +++ b/drivers/tty/serial/8250/8250_early.c
> @@ -35,18 +35,8 @@
...
> -
> -int __init setup_early_serial8250_console(char *cmdline)

You removed global function, but still left declaration and calling...

arch/mips/mti-malta/malta-init.c:
setup_early_serial8250_console(console_string);
drivers/firmware/pcdp.c:        return setup_early_serial8250_console(options);
include/linux/serial_8250.h:extern int
setup_early_serial8250_console(char *cmdline);

Yinghai

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
> From: Rob Herring <robh@kernel.org>
>
> With the generic earlycon infrastructure in place, convert the 8250
> early console to use it.
>
> Signed-off-by: Rob Herring <robh@kernel.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Jiri Slaby <jslaby@suse.cz>
> ---
>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>  drivers/tty/serial/8250/Kconfig      |   1 +
>  2 files changed, 16 insertions(+), 123 deletions(-)
>
> diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
> index c100d63..e83c9db 100644
> --- a/drivers/tty/serial/8250/8250_early.c
> +++ b/drivers/tty/serial/8250/8250_early.c
> @@ -35,18 +35,8 @@
...
> -
> -int __init setup_early_serial8250_console(char *cmdline)

You removed global function, but still left declaration and calling...

arch/mips/mti-malta/malta-init.c:
setup_early_serial8250_console(console_string);
drivers/firmware/pcdp.c:        return setup_early_serial8250_console(options);
include/linux/serial_8250.h:extern int
setup_early_serial8250_console(char *cmdline);

Yinghai

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
> From: Rob Herring <robh@kernel.org>
>
> With the generic earlycon infrastructure in place, convert the 8250
> early console to use it.
>
> Signed-off-by: Rob Herring <robh@kernel.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Jiri Slaby <jslaby@suse.cz>
> ---
>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>  drivers/tty/serial/8250/Kconfig      |   1 +
>  2 files changed, 16 insertions(+), 123 deletions(-)
>
> diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
> index c100d63..e83c9db 100644
> --- a/drivers/tty/serial/8250/8250_early.c
> +++ b/drivers/tty/serial/8250/8250_early.c
> @@ -35,18 +35,8 @@
...
> -
> -int __init setup_early_serial8250_console(char *cmdline)

You removed global function, but still left declaration and calling...

arch/mips/mti-malta/malta-init.c:
setup_early_serial8250_console(console_string);
drivers/firmware/pcdp.c:        return setup_early_serial8250_console(options);
include/linux/serial_8250.h:extern int
setup_early_serial8250_console(char *cmdline);

Yinghai

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Sat, Apr 26, 2014 at 1:19 AM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
>> From: Rob Herring <robh@kernel.org>
>>
>> With the generic earlycon infrastructure in place, convert the 8250
>> early console to use it.
>>
>> Signed-off-by: Rob Herring <robh@kernel.org>
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Cc: Jiri Slaby <jslaby@suse.cz>
>> ---
>>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>>  drivers/tty/serial/8250/Kconfig      |   1 +
>>  2 files changed, 16 insertions(+), 123 deletions(-)
>
> Hi Greg, Rob
>
> This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
> No early console and regular console anymore.
>
> It should produce "early con and regular con".

This is what I get for running checkpatch and converting
simple_strtoul to kstrto* which are not so equivalent. kstrto* will
not convert things such as 115200n8 to a number.

Greg, Do you want a fix or for me to respin the series? The fix looks like this:

diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index 73bf1e2..c92e830 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -53,7 +53,7 @@ static int __init parse_options(struct
earlycon_device *device,
                                char *options)
 {
        struct uart_port *port = &device->port;
-       int mmio, mmio32, length, ret;
+       int mmio, mmio32, length;
        unsigned long addr;

        if (!options)
@@ -64,25 +64,19 @@ static int __init parse_options(struct
earlycon_device *device,
        if (mmio || mmio32) {
                port->iotype = (mmio ? UPIO_MEM : UPIO_MEM32);
                options += mmio ? 5 : 7;
-               ret = kstrtoul(options, 0, &addr);
-               if (ret)
-                       return ret;
+               addr = simple_strtoul(options, NULL, 0);
                port->mapbase = addr;
                if (mmio32)
                        port->regshift = 2;
        } else if (!strncmp(options, "io,", 3)) {
                port->iotype = UPIO_PORT;
                options += 3;
-               ret = kstrtoul(options, 0, &addr);
-               if (ret)
-                       return ret;
+               addr = simple_strtoul(options, NULL, 0);
                port->iobase = addr;
                mmio = 0;
        } else if (!strncmp(options, "0x", 2)) {
                port->iotype = UPIO_MEM;
-               ret = kstrtoul(options, 0, &addr);
-               if (ret)
-                       return ret;
+               addr = simple_strtoul(options, NULL, 0);
                port->mapbase = addr;
        } else {
                return -EINVAL;
@@ -93,9 +87,7 @@ static int __init parse_options(struct
earlycon_device *device,
        options = strchr(options, ',');
        if (options) {
                options++;
-               ret = kstrtouint(options, 0, &device->baud);
-               if (ret)
-                       return ret;
+               device->baud = simple_strtoul(options, NULL, 0);
                length = min(strcspn(options, " ") + 1,
                             (size_t)(sizeof(device->options)));
                strlcpy(device->options, options, length);

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Sat, Apr 26, 2014 at 1:19 AM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
>> From: Rob Herring <robh@kernel.org>
>>
>> With the generic earlycon infrastructure in place, convert the 8250
>> early console to use it.
>>
>> Signed-off-by: Rob Herring <robh@kernel.org>
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Cc: Jiri Slaby <jslaby@suse.cz>
>> ---
>>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>>  drivers/tty/serial/8250/Kconfig      |   1 +
>>  2 files changed, 16 insertions(+), 123 deletions(-)
>
> Hi Greg, Rob
>
> This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
> No early console and regular console anymore.
>
> It should produce "early con and regular con".

This is what I get for running checkpatch and converting
simple_strtoul to kstrto* which are not so equivalent. kstrto* will
not convert things such as 115200n8 to a number.

Greg, Do you want a fix or for me to respin the series? The fix looks like this:

diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index 73bf1e2..c92e830 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -53,7 +53,7 @@ static int __init parse_options(struct
earlycon_device *device,
                                char *options)
 {
        struct uart_port *port = &device->port;
-       int mmio, mmio32, length, ret;
+       int mmio, mmio32, length;
        unsigned long addr;

        if (!options)
@@ -64,25 +64,19 @@ static int __init parse_options(struct
earlycon_device *device,
        if (mmio || mmio32) {
                port->iotype = (mmio ? UPIO_MEM : UPIO_MEM32);
                options += mmio ? 5 : 7;
-               ret = kstrtoul(options, 0, &addr);
-               if (ret)
-                       return ret;
+               addr = simple_strtoul(options, NULL, 0);
                port->mapbase = addr;
                if (mmio32)
                        port->regshift = 2;
        } else if (!strncmp(options, "io,", 3)) {
                port->iotype = UPIO_PORT;
                options += 3;
-               ret = kstrtoul(options, 0, &addr);
-               if (ret)
-                       return ret;
+               addr = simple_strtoul(options, NULL, 0);
                port->iobase = addr;
                mmio = 0;
        } else if (!strncmp(options, "0x", 2)) {
                port->iotype = UPIO_MEM;
-               ret = kstrtoul(options, 0, &addr);
-               if (ret)
-                       return ret;
+               addr = simple_strtoul(options, NULL, 0);
                port->mapbase = addr;
        } else {
                return -EINVAL;
@@ -93,9 +87,7 @@ static int __init parse_options(struct
earlycon_device *device,
        options = strchr(options, ',');
        if (options) {
                options++;
-               ret = kstrtouint(options, 0, &device->baud);
-               if (ret)
-                       return ret;
+               device->baud = simple_strtoul(options, NULL, 0);
                length = min(strcspn(options, " ") + 1,
                             (size_t)(sizeof(device->options)));
                strlcpy(device->options, options, length);

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Sat, Apr 26, 2014 at 1:19 AM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
>> From: Rob Herring <robh@kernel.org>
>>
>> With the generic earlycon infrastructure in place, convert the 8250
>> early console to use it.
>>
>> Signed-off-by: Rob Herring <robh@kernel.org>
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Cc: Jiri Slaby <jslaby@suse.cz>
>> ---
>>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>>  drivers/tty/serial/8250/Kconfig      |   1 +
>>  2 files changed, 16 insertions(+), 123 deletions(-)
>
> Hi Greg, Rob
>
> This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
> No early console and regular console anymore.
>
> It should produce "early con and regular con".

This is what I get for running checkpatch and converting
simple_strtoul to kstrto* which are not so equivalent. kstrto* will
not convert things such as 115200n8 to a number.

Greg, Do you want a fix or for me to respin the series? The fix looks like this:

diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index 73bf1e2..c92e830 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -53,7 +53,7 @@ static int __init parse_options(struct
earlycon_device *device,
                                char *options)
 {
        struct uart_port *port = &device->port;
-       int mmio, mmio32, length, ret;
+       int mmio, mmio32, length;
        unsigned long addr;

        if (!options)
@@ -64,25 +64,19 @@ static int __init parse_options(struct
earlycon_device *device,
        if (mmio || mmio32) {
                port->iotype = (mmio ? UPIO_MEM : UPIO_MEM32);
                options += mmio ? 5 : 7;
-               ret = kstrtoul(options, 0, &addr);
-               if (ret)
-                       return ret;
+               addr = simple_strtoul(options, NULL, 0);
                port->mapbase = addr;
                if (mmio32)
                        port->regshift = 2;
        } else if (!strncmp(options, "io,", 3)) {
                port->iotype = UPIO_PORT;
                options += 3;
-               ret = kstrtoul(options, 0, &addr);
-               if (ret)
-                       return ret;
+               addr = simple_strtoul(options, NULL, 0);
                port->iobase = addr;
                mmio = 0;
        } else if (!strncmp(options, "0x", 2)) {
                port->iotype = UPIO_MEM;
-               ret = kstrtoul(options, 0, &addr);
-               if (ret)
-                       return ret;
+               addr = simple_strtoul(options, NULL, 0);
                port->mapbase = addr;
        } else {
                return -EINVAL;
@@ -93,9 +87,7 @@ static int __init parse_options(struct
earlycon_device *device,
        options = strchr(options, ',');
        if (options) {
                options++;
-               ret = kstrtouint(options, 0, &device->baud);
-               if (ret)
-                       return ret;
+               device->baud = simple_strtoul(options, NULL, 0);
                length = min(strcspn(options, " ") + 1,
                             (size_t)(sizeof(device->options)));
                strlcpy(device->options, options, length);

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
>> From: Rob Herring <robh@kernel.org>
>>
>> With the generic earlycon infrastructure in place, convert the 8250
>> early console to use it.
>>
>> Signed-off-by: Rob Herring <robh@kernel.org>
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Cc: Jiri Slaby <jslaby@suse.cz>
>> ---
>>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>>  drivers/tty/serial/8250/Kconfig      |   1 +
>>  2 files changed, 16 insertions(+), 123 deletions(-)
>>
>> diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
>> index c100d63..e83c9db 100644
>> --- a/drivers/tty/serial/8250/8250_early.c
>> +++ b/drivers/tty/serial/8250/8250_early.c
>> @@ -35,18 +35,8 @@
> ...
>> -
>> -int __init setup_early_serial8250_console(char *cmdline)
>
> You removed global function, but still left declaration and calling...
>
> arch/mips/mti-malta/malta-init.c:
> setup_early_serial8250_console(console_string);
> drivers/firmware/pcdp.c:        return setup_early_serial8250_console(options);
> include/linux/serial_8250.h:extern int
> setup_early_serial8250_console(char *cmdline);

Thanks for finding these. I missed them in my build tests. This should fix them:

diff --git a/drivers/tty/serial/8250/8250_early.c
b/drivers/tty/serial/8250/8250_early.c
index e83c9db..2094c3b 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
earlycon_device *device,
 EARLYCON_DECLARE(uart8250, early_serial8250_setup);
 EARLYCON_DECLARE(uart, early_serial8250_setup);

+int __init setup_early_serial8250_console(char *cmdline)
+{
+       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
+}
+
 int serial8250_find_port_for_earlycon(void)
 {
        struct earlycon_device *device = early_device;

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
>> From: Rob Herring <robh@kernel.org>
>>
>> With the generic earlycon infrastructure in place, convert the 8250
>> early console to use it.
>>
>> Signed-off-by: Rob Herring <robh@kernel.org>
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Cc: Jiri Slaby <jslaby@suse.cz>
>> ---
>>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>>  drivers/tty/serial/8250/Kconfig      |   1 +
>>  2 files changed, 16 insertions(+), 123 deletions(-)
>>
>> diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
>> index c100d63..e83c9db 100644
>> --- a/drivers/tty/serial/8250/8250_early.c
>> +++ b/drivers/tty/serial/8250/8250_early.c
>> @@ -35,18 +35,8 @@
> ...
>> -
>> -int __init setup_early_serial8250_console(char *cmdline)
>
> You removed global function, but still left declaration and calling...
>
> arch/mips/mti-malta/malta-init.c:
> setup_early_serial8250_console(console_string);
> drivers/firmware/pcdp.c:        return setup_early_serial8250_console(options);
> include/linux/serial_8250.h:extern int
> setup_early_serial8250_console(char *cmdline);

Thanks for finding these. I missed them in my build tests. This should fix them:

diff --git a/drivers/tty/serial/8250/8250_early.c
b/drivers/tty/serial/8250/8250_early.c
index e83c9db..2094c3b 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
earlycon_device *device,
 EARLYCON_DECLARE(uart8250, early_serial8250_setup);
 EARLYCON_DECLARE(uart, early_serial8250_setup);

+int __init setup_early_serial8250_console(char *cmdline)
+{
+       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
+}
+
 int serial8250_find_port_for_earlycon(void)
 {
        struct earlycon_device *device = early_device;

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
>> From: Rob Herring <robh@kernel.org>
>>
>> With the generic earlycon infrastructure in place, convert the 8250
>> early console to use it.
>>
>> Signed-off-by: Rob Herring <robh@kernel.org>
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> Cc: Jiri Slaby <jslaby@suse.cz>
>> ---
>>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>>  drivers/tty/serial/8250/Kconfig      |   1 +
>>  2 files changed, 16 insertions(+), 123 deletions(-)
>>
>> diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
>> index c100d63..e83c9db 100644
>> --- a/drivers/tty/serial/8250/8250_early.c
>> +++ b/drivers/tty/serial/8250/8250_early.c
>> @@ -35,18 +35,8 @@
> ...
>> -
>> -int __init setup_early_serial8250_console(char *cmdline)
>
> You removed global function, but still left declaration and calling...
>
> arch/mips/mti-malta/malta-init.c:
> setup_early_serial8250_console(console_string);
> drivers/firmware/pcdp.c:        return setup_early_serial8250_console(options);
> include/linux/serial_8250.h:extern int
> setup_early_serial8250_console(char *cmdline);

Thanks for finding these. I missed them in my build tests. This should fix them:

diff --git a/drivers/tty/serial/8250/8250_early.c
b/drivers/tty/serial/8250/8250_early.c
index e83c9db..2094c3b 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
earlycon_device *device,
 EARLYCON_DECLARE(uart8250, early_serial8250_setup);
 EARLYCON_DECLARE(uart, early_serial8250_setup);

+int __init setup_early_serial8250_console(char *cmdline)
+{
+       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
+}
+
 int serial8250_find_port_for_earlycon(void)
 {
        struct earlycon_device *device = early_device;

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Mon, Apr 28, 2014 at 4:24 PM, Rob Herring <robherring2@gmail.com> wrote:
> On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
>
> Thanks for finding these. I missed them in my build tests. This should fix them:
>
> diff --git a/drivers/tty/serial/8250/8250_early.c
> b/drivers/tty/serial/8250/8250_early.c
> index e83c9db..2094c3b 100644
> --- a/drivers/tty/serial/8250/8250_early.c
> +++ b/drivers/tty/serial/8250/8250_early.c
> @@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
> earlycon_device *device,
>  EARLYCON_DECLARE(uart8250, early_serial8250_setup);
>  EARLYCON_DECLARE(uart, early_serial8250_setup);
>
> +int __init setup_early_serial8250_console(char *cmdline)
> +{
> +       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
> +}
> +
>  int serial8250_find_port_for_earlycon(void)
>  {
>         struct earlycon_device *device = early_device;

that only handle "uart8250,", may need to add more lines to handle "uart,"

+int __init setup_early_serial8250_console(char *cmdline)
+{
+       char *options;
+       options = strstr(cmdline, "uart8250,");
+       if (options)
+               return setup_earlycon(cmdline, "uart8250",
early_serial8250_setup);
+
+       options = strstr(cmdline, "uart,");
+       if (options)
+              return setup_earlycon(cmdline, "uart", early_serial8250_setup);
+
+      return 0;
+}
+

Thanks

Yinghai

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Mon, Apr 28, 2014 at 4:24 PM, Rob Herring <robherring2@gmail.com> wrote:
> On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
>
> Thanks for finding these. I missed them in my build tests. This should fix them:
>
> diff --git a/drivers/tty/serial/8250/8250_early.c
> b/drivers/tty/serial/8250/8250_early.c
> index e83c9db..2094c3b 100644
> --- a/drivers/tty/serial/8250/8250_early.c
> +++ b/drivers/tty/serial/8250/8250_early.c
> @@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
> earlycon_device *device,
>  EARLYCON_DECLARE(uart8250, early_serial8250_setup);
>  EARLYCON_DECLARE(uart, early_serial8250_setup);
>
> +int __init setup_early_serial8250_console(char *cmdline)
> +{
> +       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
> +}
> +
>  int serial8250_find_port_for_earlycon(void)
>  {
>         struct earlycon_device *device = early_device;

that only handle "uart8250,", may need to add more lines to handle "uart,"

+int __init setup_early_serial8250_console(char *cmdline)
+{
+       char *options;
+       options = strstr(cmdline, "uart8250,");
+       if (options)
+               return setup_earlycon(cmdline, "uart8250",
early_serial8250_setup);
+
+       options = strstr(cmdline, "uart,");
+       if (options)
+              return setup_earlycon(cmdline, "uart", early_serial8250_setup);
+
+      return 0;
+}
+

Thanks

Yinghai

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Mon, Apr 28, 2014 at 4:24 PM, Rob Herring <robherring2@gmail.com> wrote:
> On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
>
> Thanks for finding these. I missed them in my build tests. This should fix them:
>
> diff --git a/drivers/tty/serial/8250/8250_early.c
> b/drivers/tty/serial/8250/8250_early.c
> index e83c9db..2094c3b 100644
> --- a/drivers/tty/serial/8250/8250_early.c
> +++ b/drivers/tty/serial/8250/8250_early.c
> @@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
> earlycon_device *device,
>  EARLYCON_DECLARE(uart8250, early_serial8250_setup);
>  EARLYCON_DECLARE(uart, early_serial8250_setup);
>
> +int __init setup_early_serial8250_console(char *cmdline)
> +{
> +       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
> +}
> +
>  int serial8250_find_port_for_earlycon(void)
>  {
>         struct earlycon_device *device = early_device;

that only handle "uart8250,", may need to add more lines to handle "uart,"

+int __init setup_early_serial8250_console(char *cmdline)
+{
+       char *options;
+       options = strstr(cmdline, "uart8250,");
+       if (options)
+               return setup_earlycon(cmdline, "uart8250",
early_serial8250_setup);
+
+       options = strstr(cmdline, "uart,");
+       if (options)
+              return setup_earlycon(cmdline, "uart", early_serial8250_setup);
+
+      return 0;
+}
+

Thanks

Yinghai

Re: [PATCH v2 0/7] Generic serial earlycon

[Catalin Marinas]

On Fri, Apr 18, 2014 at 11:19:53PM +0100, Rob Herring wrote:
> Rob Herring (7):
>   x86: move FIX_EARLYCON_MEM kconfig into x86
>   tty/serial: add generic serial earlycon
>   tty/serial: convert 8250 to generic earlycon
>   tty/serial: pl011: add generic earlycon support
>   tty/serial: add arm/arm64 semihosting earlycon
>   arm64: enable FIX_EARLYCON_MEM kconfig
>   arm64: remove arch specific earlyprintk

The series looks fine, you can add:

Acked-by: Catalin Marinas <catalin.marinas@arm.com>

BTW, are you merging all of them via some other tree or would prefer me
to take the arm64-specific patches?

Re: [PATCH v2 0/7] Generic serial earlycon

[Catalin Marinas]

On Fri, Apr 18, 2014 at 11:19:53PM +0100, Rob Herring wrote:
> Rob Herring (7):
>   x86: move FIX_EARLYCON_MEM kconfig into x86
>   tty/serial: add generic serial earlycon
>   tty/serial: convert 8250 to generic earlycon
>   tty/serial: pl011: add generic earlycon support
>   tty/serial: add arm/arm64 semihosting earlycon
>   arm64: enable FIX_EARLYCON_MEM kconfig
>   arm64: remove arch specific earlyprintk

The series looks fine, you can add:

Acked-by: Catalin Marinas <catalin.marinas@arm.com>

BTW, are you merging all of them via some other tree or would prefer me
to take the arm64-specific patches?

[PATCH v2 0/7] Generic serial earlycon

[Catalin Marinas]

On Fri, Apr 18, 2014 at 11:19:53PM +0100, Rob Herring wrote:
> Rob Herring (7):
>   x86: move FIX_EARLYCON_MEM kconfig into x86
>   tty/serial: add generic serial earlycon
>   tty/serial: convert 8250 to generic earlycon
>   tty/serial: pl011: add generic earlycon support
>   tty/serial: add arm/arm64 semihosting earlycon
>   arm64: enable FIX_EARLYCON_MEM kconfig
>   arm64: remove arch specific earlyprintk

The series looks fine, you can add:

Acked-by: Catalin Marinas <catalin.marinas@arm.com>

BTW, are you merging all of them via some other tree or would prefer me
to take the arm64-specific patches?

Re: [PATCH v2 0/7] Generic serial earlycon

[Rob Herring]

On Tue, Apr 29, 2014 at 6:09 AM, Catalin Marinas
<catalin.marinas@arm.com> wrote:
> On Fri, Apr 18, 2014 at 11:19:53PM +0100, Rob Herring wrote:
>> Rob Herring (7):
>>   x86: move FIX_EARLYCON_MEM kconfig into x86
>>   tty/serial: add generic serial earlycon
>>   tty/serial: convert 8250 to generic earlycon
>>   tty/serial: pl011: add generic earlycon support
>>   tty/serial: add arm/arm64 semihosting earlycon
>>   arm64: enable FIX_EARLYCON_MEM kconfig
>>   arm64: remove arch specific earlyprintk
>
> The series looks fine, you can add:
>
> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
>

Thanks.

> BTW, are you merging all of them via some other tree or would prefer me
> to take the arm64-specific patches?

Greg has taken it, but there were a few issues, so it may get reposted.

Rob

Re: [PATCH v2 0/7] Generic serial earlycon

[Rob Herring]

On Tue, Apr 29, 2014 at 6:09 AM, Catalin Marinas
<catalin.marinas@arm.com> wrote:
> On Fri, Apr 18, 2014 at 11:19:53PM +0100, Rob Herring wrote:
>> Rob Herring (7):
>>   x86: move FIX_EARLYCON_MEM kconfig into x86
>>   tty/serial: add generic serial earlycon
>>   tty/serial: convert 8250 to generic earlycon
>>   tty/serial: pl011: add generic earlycon support
>>   tty/serial: add arm/arm64 semihosting earlycon
>>   arm64: enable FIX_EARLYCON_MEM kconfig
>>   arm64: remove arch specific earlyprintk
>
> The series looks fine, you can add:
>
> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
>

Thanks.

> BTW, are you merging all of them via some other tree or would prefer me
> to take the arm64-specific patches?

Greg has taken it, but there were a few issues, so it may get reposted.

Rob

[PATCH v2 0/7] Generic serial earlycon

[Rob Herring]

On Tue, Apr 29, 2014 at 6:09 AM, Catalin Marinas
<catalin.marinas@arm.com> wrote:
> On Fri, Apr 18, 2014 at 11:19:53PM +0100, Rob Herring wrote:
>> Rob Herring (7):
>>   x86: move FIX_EARLYCON_MEM kconfig into x86
>>   tty/serial: add generic serial earlycon
>>   tty/serial: convert 8250 to generic earlycon
>>   tty/serial: pl011: add generic earlycon support
>>   tty/serial: add arm/arm64 semihosting earlycon
>>   arm64: enable FIX_EARLYCON_MEM kconfig
>>   arm64: remove arch specific earlyprintk
>
> The series looks fine, you can add:
>
> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
>

Thanks.

> BTW, are you merging all of them via some other tree or would prefer me
> to take the arm64-specific patches?

Greg has taken it, but there were a few issues, so it may get reposted.

Rob

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Mon, Apr 28, 2014 at 9:56 PM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Mon, Apr 28, 2014 at 4:24 PM, Rob Herring <robherring2@gmail.com> wrote:
>> On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
>>
>> Thanks for finding these. I missed them in my build tests. This should fix them:
>>
>> diff --git a/drivers/tty/serial/8250/8250_early.c
>> b/drivers/tty/serial/8250/8250_early.c
>> index e83c9db..2094c3b 100644
>> --- a/drivers/tty/serial/8250/8250_early.c
>> +++ b/drivers/tty/serial/8250/8250_early.c
>> @@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
>> earlycon_device *device,
>>  EARLYCON_DECLARE(uart8250, early_serial8250_setup);
>>  EARLYCON_DECLARE(uart, early_serial8250_setup);
>>
>> +int __init setup_early_serial8250_console(char *cmdline)
>> +{
>> +       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
>> +}
>> +
>>  int serial8250_find_port_for_earlycon(void)
>>  {
>>         struct earlycon_device *device = early_device;
>
> that only handle "uart8250,", may need to add more lines to handle "uart,"


That is on purpose because the only 2 users use uart8250. I consider
this a legacy interface and use of "uart" is horrible because there
are lots of uarts which are not 8250.

Rob

>
> +int __init setup_early_serial8250_console(char *cmdline)
> +{
> +       char *options;
> +       options = strstr(cmdline, "uart8250,");
> +       if (options)
> +               return setup_earlycon(cmdline, "uart8250",
> early_serial8250_setup);
> +
> +       options = strstr(cmdline, "uart,");
> +       if (options)
> +              return setup_earlycon(cmdline, "uart", early_serial8250_setup);
> +
> +      return 0;
> +}
> +
>
> Thanks
>
> Yinghai

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Mon, Apr 28, 2014 at 9:56 PM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Mon, Apr 28, 2014 at 4:24 PM, Rob Herring <robherring2@gmail.com> wrote:
>> On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
>>
>> Thanks for finding these. I missed them in my build tests. This should fix them:
>>
>> diff --git a/drivers/tty/serial/8250/8250_early.c
>> b/drivers/tty/serial/8250/8250_early.c
>> index e83c9db..2094c3b 100644
>> --- a/drivers/tty/serial/8250/8250_early.c
>> +++ b/drivers/tty/serial/8250/8250_early.c
>> @@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
>> earlycon_device *device,
>>  EARLYCON_DECLARE(uart8250, early_serial8250_setup);
>>  EARLYCON_DECLARE(uart, early_serial8250_setup);
>>
>> +int __init setup_early_serial8250_console(char *cmdline)
>> +{
>> +       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
>> +}
>> +
>>  int serial8250_find_port_for_earlycon(void)
>>  {
>>         struct earlycon_device *device = early_device;
>
> that only handle "uart8250,", may need to add more lines to handle "uart,"


That is on purpose because the only 2 users use uart8250. I consider
this a legacy interface and use of "uart" is horrible because there
are lots of uarts which are not 8250.

Rob

>
> +int __init setup_early_serial8250_console(char *cmdline)
> +{
> +       char *options;
> +       options = strstr(cmdline, "uart8250,");
> +       if (options)
> +               return setup_earlycon(cmdline, "uart8250",
> early_serial8250_setup);
> +
> +       options = strstr(cmdline, "uart,");
> +       if (options)
> +              return setup_earlycon(cmdline, "uart", early_serial8250_setup);
> +
> +      return 0;
> +}
> +
>
> Thanks
>
> Yinghai

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Mon, Apr 28, 2014 at 9:56 PM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Mon, Apr 28, 2014 at 4:24 PM, Rob Herring <robherring2@gmail.com> wrote:
>> On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
>>
>> Thanks for finding these. I missed them in my build tests. This should fix them:
>>
>> diff --git a/drivers/tty/serial/8250/8250_early.c
>> b/drivers/tty/serial/8250/8250_early.c
>> index e83c9db..2094c3b 100644
>> --- a/drivers/tty/serial/8250/8250_early.c
>> +++ b/drivers/tty/serial/8250/8250_early.c
>> @@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
>> earlycon_device *device,
>>  EARLYCON_DECLARE(uart8250, early_serial8250_setup);
>>  EARLYCON_DECLARE(uart, early_serial8250_setup);
>>
>> +int __init setup_early_serial8250_console(char *cmdline)
>> +{
>> +       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
>> +}
>> +
>>  int serial8250_find_port_for_earlycon(void)
>>  {
>>         struct earlycon_device *device = early_device;
>
> that only handle "uart8250,", may need to add more lines to handle "uart,"


That is on purpose because the only 2 users use uart8250. I consider
this a legacy interface and use of "uart" is horrible because there
are lots of uarts which are not 8250.

Rob

>
> +int __init setup_early_serial8250_console(char *cmdline)
> +{
> +       char *options;
> +       options = strstr(cmdline, "uart8250,");
> +       if (options)
> +               return setup_earlycon(cmdline, "uart8250",
> early_serial8250_setup);
> +
> +       options = strstr(cmdline, "uart,");
> +       if (options)
> +              return setup_earlycon(cmdline, "uart", early_serial8250_setup);
> +
> +      return 0;
> +}
> +
>
> Thanks
>
> Yinghai

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Tue, Apr 29, 2014 at 8:16 AM, Rob Herring <robherring2@gmail.com> wrote:
> On Mon, Apr 28, 2014 at 9:56 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>> On Mon, Apr 28, 2014 at 4:24 PM, Rob Herring <robherring2@gmail.com> wrote:
>>> On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
>>>
>>> Thanks for finding these. I missed them in my build tests. This should fix them:
>>>
>>> diff --git a/drivers/tty/serial/8250/8250_early.c
>>> b/drivers/tty/serial/8250/8250_early.c
>>> index e83c9db..2094c3b 100644
>>> --- a/drivers/tty/serial/8250/8250_early.c
>>> +++ b/drivers/tty/serial/8250/8250_early.c
>>> @@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
>>> earlycon_device *device,
>>>  EARLYCON_DECLARE(uart8250, early_serial8250_setup);
>>>  EARLYCON_DECLARE(uart, early_serial8250_setup);
>>>
>>> +int __init setup_early_serial8250_console(char *cmdline)
>>> +{
>>> +       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
>>> +}
>>> +
>>>  int serial8250_find_port_for_earlycon(void)
>>>  {
>>>         struct earlycon_device *device = early_device;
>>
>> that only handle "uart8250,", may need to add more lines to handle "uart,"
>
>
> That is on purpose because the only 2 users use uart8250. I consider
> this a legacy interface and use of "uart" is horrible because there
> are lots of uarts which are not 8250.
>
> Rob
>
>>
>> +int __init setup_early_serial8250_console(char *cmdline)
>> +{
>> +       char *options;
>> +       options = strstr(cmdline, "uart8250,");
>> +       if (options)
>> +               return setup_earlycon(cmdline, "uart8250",
>> early_serial8250_setup);
>> +
>> +       options = strstr(cmdline, "uart,");
>> +       if (options)
>> +              return setup_earlycon(cmdline, "uart", early_serial8250_setup);
>> +
>> +      return 0;
>> +}

You want to obsolete "console=uart,io,0x3f8,115200n8" ?

 Let's check with Andrew. He suggested to use uart and uart8250 at that time.

Thanks

Yinghai

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Tue, Apr 29, 2014 at 8:16 AM, Rob Herring <robherring2@gmail.com> wrote:
> On Mon, Apr 28, 2014 at 9:56 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>> On Mon, Apr 28, 2014 at 4:24 PM, Rob Herring <robherring2@gmail.com> wrote:
>>> On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
>>>
>>> Thanks for finding these. I missed them in my build tests. This should fix them:
>>>
>>> diff --git a/drivers/tty/serial/8250/8250_early.c
>>> b/drivers/tty/serial/8250/8250_early.c
>>> index e83c9db..2094c3b 100644
>>> --- a/drivers/tty/serial/8250/8250_early.c
>>> +++ b/drivers/tty/serial/8250/8250_early.c
>>> @@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
>>> earlycon_device *device,
>>>  EARLYCON_DECLARE(uart8250, early_serial8250_setup);
>>>  EARLYCON_DECLARE(uart, early_serial8250_setup);
>>>
>>> +int __init setup_early_serial8250_console(char *cmdline)
>>> +{
>>> +       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
>>> +}
>>> +
>>>  int serial8250_find_port_for_earlycon(void)
>>>  {
>>>         struct earlycon_device *device = early_device;
>>
>> that only handle "uart8250,", may need to add more lines to handle "uart,"
>
>
> That is on purpose because the only 2 users use uart8250. I consider
> this a legacy interface and use of "uart" is horrible because there
> are lots of uarts which are not 8250.
>
> Rob
>
>>
>> +int __init setup_early_serial8250_console(char *cmdline)
>> +{
>> +       char *options;
>> +       options = strstr(cmdline, "uart8250,");
>> +       if (options)
>> +               return setup_earlycon(cmdline, "uart8250",
>> early_serial8250_setup);
>> +
>> +       options = strstr(cmdline, "uart,");
>> +       if (options)
>> +              return setup_earlycon(cmdline, "uart", early_serial8250_setup);
>> +
>> +      return 0;
>> +}

You want to obsolete "console=uart,io,0x3f8,115200n8" ?

 Let's check with Andrew. He suggested to use uart and uart8250 at that time.

Thanks

Yinghai

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Tue, Apr 29, 2014 at 8:16 AM, Rob Herring <robherring2@gmail.com> wrote:
> On Mon, Apr 28, 2014 at 9:56 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>> On Mon, Apr 28, 2014 at 4:24 PM, Rob Herring <robherring2@gmail.com> wrote:
>>> On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
>>>
>>> Thanks for finding these. I missed them in my build tests. This should fix them:
>>>
>>> diff --git a/drivers/tty/serial/8250/8250_early.c
>>> b/drivers/tty/serial/8250/8250_early.c
>>> index e83c9db..2094c3b 100644
>>> --- a/drivers/tty/serial/8250/8250_early.c
>>> +++ b/drivers/tty/serial/8250/8250_early.c
>>> @@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
>>> earlycon_device *device,
>>>  EARLYCON_DECLARE(uart8250, early_serial8250_setup);
>>>  EARLYCON_DECLARE(uart, early_serial8250_setup);
>>>
>>> +int __init setup_early_serial8250_console(char *cmdline)
>>> +{
>>> +       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
>>> +}
>>> +
>>>  int serial8250_find_port_for_earlycon(void)
>>>  {
>>>         struct earlycon_device *device = early_device;
>>
>> that only handle "uart8250,", may need to add more lines to handle "uart,"
>
>
> That is on purpose because the only 2 users use uart8250. I consider
> this a legacy interface and use of "uart" is horrible because there
> are lots of uarts which are not 8250.
>
> Rob
>
>>
>> +int __init setup_early_serial8250_console(char *cmdline)
>> +{
>> +       char *options;
>> +       options = strstr(cmdline, "uart8250,");
>> +       if (options)
>> +               return setup_earlycon(cmdline, "uart8250",
>> early_serial8250_setup);
>> +
>> +       options = strstr(cmdline, "uart,");
>> +       if (options)
>> +              return setup_earlycon(cmdline, "uart", early_serial8250_setup);
>> +
>> +      return 0;
>> +}

You want to obsolete "console=uart,io,0x3f8,115200n8" ?

 Let's check with Andrew. He suggested to use uart and uart8250 at that time.

Thanks

Yinghai

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Tue, Apr 29, 2014 at 1:22 PM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Tue, Apr 29, 2014 at 8:16 AM, Rob Herring <robherring2@gmail.com> wrote:
>> On Mon, Apr 28, 2014 at 9:56 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>>> On Mon, Apr 28, 2014 at 4:24 PM, Rob Herring <robherring2@gmail.com> wrote:
>>>> On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
>>>>
>>>> Thanks for finding these. I missed them in my build tests. This should fix them:
>>>>
>>>> diff --git a/drivers/tty/serial/8250/8250_early.c
>>>> b/drivers/tty/serial/8250/8250_early.c
>>>> index e83c9db..2094c3b 100644
>>>> --- a/drivers/tty/serial/8250/8250_early.c
>>>> +++ b/drivers/tty/serial/8250/8250_early.c
>>>> @@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
>>>> earlycon_device *device,
>>>>  EARLYCON_DECLARE(uart8250, early_serial8250_setup);
>>>>  EARLYCON_DECLARE(uart, early_serial8250_setup);
>>>>
>>>> +int __init setup_early_serial8250_console(char *cmdline)
>>>> +{
>>>> +       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
>>>> +}
>>>> +
>>>>  int serial8250_find_port_for_earlycon(void)
>>>>  {
>>>>         struct earlycon_device *device = early_device;
>>>
>>> that only handle "uart8250,", may need to add more lines to handle "uart,"
>>
>>
>> That is on purpose because the only 2 users use uart8250. I consider
>> this a legacy interface and use of "uart" is horrible because there
>> are lots of uarts which are not 8250.
>>
>> Rob
>>
>>>
>>> +int __init setup_early_serial8250_console(char *cmdline)
>>> +{
>>> +       char *options;
>>> +       options = strstr(cmdline, "uart8250,");
>>> +       if (options)
>>> +               return setup_earlycon(cmdline, "uart8250",
>>> early_serial8250_setup);
>>> +
>>> +       options = strstr(cmdline, "uart,");
>>> +       if (options)
>>> +              return setup_earlycon(cmdline, "uart", early_serial8250_setup);
>>> +
>>> +      return 0;
>>> +}
>
> You want to obsolete "console=uart,io,0x3f8,115200n8" ?
>
>  Let's check with Andrew. He suggested to use uart and uart8250 at that time.

No, that is not what I'm saying. For the 2 callers of
setup_early_serial8250_console which are crafting a console string
from firmware data, they can and do use uart8250. I don't expect this
mechanism for setting up early console to expand to other users. The
whole point of this series is to allow any uart to be supported for
earlycon. For anyone using the kernel command line, both uart and
uart8250 are still supported.

Rob

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Tue, Apr 29, 2014 at 1:22 PM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Tue, Apr 29, 2014 at 8:16 AM, Rob Herring <robherring2@gmail.com> wrote:
>> On Mon, Apr 28, 2014 at 9:56 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>>> On Mon, Apr 28, 2014 at 4:24 PM, Rob Herring <robherring2@gmail.com> wrote:
>>>> On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
>>>>
>>>> Thanks for finding these. I missed them in my build tests. This should fix them:
>>>>
>>>> diff --git a/drivers/tty/serial/8250/8250_early.c
>>>> b/drivers/tty/serial/8250/8250_early.c
>>>> index e83c9db..2094c3b 100644
>>>> --- a/drivers/tty/serial/8250/8250_early.c
>>>> +++ b/drivers/tty/serial/8250/8250_early.c
>>>> @@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
>>>> earlycon_device *device,
>>>>  EARLYCON_DECLARE(uart8250, early_serial8250_setup);
>>>>  EARLYCON_DECLARE(uart, early_serial8250_setup);
>>>>
>>>> +int __init setup_early_serial8250_console(char *cmdline)
>>>> +{
>>>> +       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
>>>> +}
>>>> +
>>>>  int serial8250_find_port_for_earlycon(void)
>>>>  {
>>>>         struct earlycon_device *device = early_device;
>>>
>>> that only handle "uart8250,", may need to add more lines to handle "uart,"
>>
>>
>> That is on purpose because the only 2 users use uart8250. I consider
>> this a legacy interface and use of "uart" is horrible because there
>> are lots of uarts which are not 8250.
>>
>> Rob
>>
>>>
>>> +int __init setup_early_serial8250_console(char *cmdline)
>>> +{
>>> +       char *options;
>>> +       options = strstr(cmdline, "uart8250,");
>>> +       if (options)
>>> +               return setup_earlycon(cmdline, "uart8250",
>>> early_serial8250_setup);
>>> +
>>> +       options = strstr(cmdline, "uart,");
>>> +       if (options)
>>> +              return setup_earlycon(cmdline, "uart", early_serial8250_setup);
>>> +
>>> +      return 0;
>>> +}
>
> You want to obsolete "console=uart,io,0x3f8,115200n8" ?
>
>  Let's check with Andrew. He suggested to use uart and uart8250 at that time.

No, that is not what I'm saying. For the 2 callers of
setup_early_serial8250_console which are crafting a console string
from firmware data, they can and do use uart8250. I don't expect this
mechanism for setting up early console to expand to other users. The
whole point of this series is to allow any uart to be supported for
earlycon. For anyone using the kernel command line, both uart and
uart8250 are still supported.

Rob

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Tue, Apr 29, 2014 at 1:22 PM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Tue, Apr 29, 2014 at 8:16 AM, Rob Herring <robherring2@gmail.com> wrote:
>> On Mon, Apr 28, 2014 at 9:56 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>>> On Mon, Apr 28, 2014 at 4:24 PM, Rob Herring <robherring2@gmail.com> wrote:
>>>> On Sat, Apr 26, 2014 at 1:29 AM, Yinghai Lu <yinghai@kernel.org> wrote:
>>>>
>>>> Thanks for finding these. I missed them in my build tests. This should fix them:
>>>>
>>>> diff --git a/drivers/tty/serial/8250/8250_early.c
>>>> b/drivers/tty/serial/8250/8250_early.c
>>>> index e83c9db..2094c3b 100644
>>>> --- a/drivers/tty/serial/8250/8250_early.c
>>>> +++ b/drivers/tty/serial/8250/8250_early.c
>>>> @@ -156,6 +156,11 @@ static int __init early_serial8250_setup(struct
>>>> earlycon_device *device,
>>>>  EARLYCON_DECLARE(uart8250, early_serial8250_setup);
>>>>  EARLYCON_DECLARE(uart, early_serial8250_setup);
>>>>
>>>> +int __init setup_early_serial8250_console(char *cmdline)
>>>> +{
>>>> +       return setup_earlycon(cmdline, "uart8250", early_serial8250_setup);
>>>> +}
>>>> +
>>>>  int serial8250_find_port_for_earlycon(void)
>>>>  {
>>>>         struct earlycon_device *device = early_device;
>>>
>>> that only handle "uart8250,", may need to add more lines to handle "uart,"
>>
>>
>> That is on purpose because the only 2 users use uart8250. I consider
>> this a legacy interface and use of "uart" is horrible because there
>> are lots of uarts which are not 8250.
>>
>> Rob
>>
>>>
>>> +int __init setup_early_serial8250_console(char *cmdline)
>>> +{
>>> +       char *options;
>>> +       options = strstr(cmdline, "uart8250,");
>>> +       if (options)
>>> +               return setup_earlycon(cmdline, "uart8250",
>>> early_serial8250_setup);
>>> +
>>> +       options = strstr(cmdline, "uart,");
>>> +       if (options)
>>> +              return setup_earlycon(cmdline, "uart", early_serial8250_setup);
>>> +
>>> +      return 0;
>>> +}
>
> You want to obsolete "console=uart,io,0x3f8,115200n8" ?
>
>  Let's check with Andrew. He suggested to use uart and uart8250 at that time.

No, that is not what I'm saying. For the 2 callers of
setup_early_serial8250_console which are crafting a console string
from firmware data, they can and do use uart8250. I don't expect this
mechanism for setting up early console to expand to other users. The
whole point of this series is to allow any uart to be supported for
earlycon. For anyone using the kernel command line, both uart and
uart8250 are still supported.

Rob

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

[-- Attachment #1: Type: text/plain, Size: 5384 bytes --]

On Tue, Apr 29, 2014 at 1:41 PM, Rob Herring <robherring2@gmail.com> wrote:
> On Tue, Apr 29, 2014 at 1:22 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>>
>> You want to obsolete "console=uart,io,0x3f8,115200n8" ?
>>
>>  Let's check with Andrew. He suggested to use uart and uart8250 at that time.
>
> No, that is not what I'm saying. For the 2 callers of
> setup_early_serial8250_console which are crafting a console string
> from firmware data, they can and do use uart8250. I don't expect this
> mechanism for setting up early console to expand to other users. The
> whole point of this series is to allow any uart to be supported for
> earlycon. For anyone using the kernel command line, both uart and
> uart8250 are still supported.

That is confusing, why not keeping them consistent?

I posted one patch before about "early early console for x86", and it
is in my local tree
 for some time.support both "uart,io" and "uart8250,io".

Peter, Can you check that patch again?  --- updated version attached.
and inlined.

Thanks

Yinghai

Subject: [PATCH -v4] x86: Setup early console as early as possible in
x86_start_kernel()

Analyze "console=uart8250,io,0x3f8,115200n8" in
i386_start_kernel/x86_64_start_kernel,
and call setup_early_serial8250_console() to init early serial console.

Only can handle io port kind of 8250, because mmio need ioremap.

Use boot_params.hdr.version instead of adding another variable,
Suggested by hpa.
Also need to apply this one after x86 memblock patchset.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 arch/x86/include/asm/setup.h |    2 ++
 arch/x86/kernel/head.c       |   26 ++++++++++++++++++++++++++
 arch/x86/kernel/head32.c     |    1 +
 arch/x86/kernel/head64.c     |    5 ++++-
 kernel/printk/printk.c       |   11 +++++++----
 5 files changed, 40 insertions(+), 5 deletions(-)

Index: linux-2.6/arch/x86/include/asm/setup.h
===================================================================
--- linux-2.6.orig/arch/x86/include/asm/setup.h
+++ linux-2.6/arch/x86/include/asm/setup.h
@@ -49,6 +49,8 @@ static inline void x86_acpi_override_fin
 #endif

 extern unsigned long saved_video_mode;
+int setup_early_serial8250_console(char *cmdline);
+void setup_early_console(void);

 extern void reserve_standard_io_resources(void);
 extern void i386_reserve_resources(void);
Index: linux-2.6/arch/x86/kernel/head.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head.c
+++ linux-2.6/arch/x86/kernel/head.c
@@ -69,3 +69,29 @@ void __init reserve_ebda_region(void)
     /* reserve all memory between lowmem and the 1MB mark */
     memblock_reserve(lowmem, 0x100000 - lowmem);
 }
+
+void __init setup_early_console(void)
+{
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+    char constr[64], *p, *q;
+
+    /* Can not handle mmio type 8250 uart yet, too early */
+    p = strstr(boot_command_line, "console=uart8250,io,");
+    if (!p)
+        p = strstr(boot_command_line, "console=uart,io,");
+    if (!p)
+        return;
+
+    p += 8;    /* sizeof "console=" */
+    q = strchr(p, ' ');
+    if ((q - p) >= sizeof(constr))
+        return;
+
+    memset(constr, 0, sizeof(constr));
+    memcpy(constr, p, q - p);
+
+    lockdep_init();
+
+    setup_early_serial8250_console(constr);
+#endif
+}
Index: linux-2.6/arch/x86/kernel/head32.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head32.c
+++ linux-2.6/arch/x86/kernel/head32.c
@@ -32,6 +32,7 @@ static void __init i386_default_early_se
 void __init i386_start_kernel(void)
 {
     sanitize_boot_params(&boot_params);
+    setup_early_console();

     /* Call the subarch specific early setup function */
     switch (boot_params.hdr.hardware_subarch) {
Index: linux-2.6/arch/x86/kernel/head64.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head64.c
+++ linux-2.6/arch/x86/kernel/head64.c
@@ -166,6 +166,7 @@ void __init x86_64_start_kernel(char * r
     load_idt((const struct desc_ptr *)&idt_descr);

     copy_bootdata(__va(real_mode_data));
+    setup_early_console();

     /*
      * Load microcode early on BSP.
@@ -187,8 +188,10 @@ void __init x86_64_start_kernel(char * r
 void __init x86_64_start_reservations(char *real_mode_data)
 {
     /* version is always not zero if it is copied */
-    if (!boot_params.hdr.version)
+    if (!boot_params.hdr.version) {
         copy_bootdata(__va(real_mode_data));
+        setup_early_console();
+    }

     reserve_ebda_region();

Index: linux-2.6/kernel/printk/printk.c
===================================================================
--- linux-2.6.orig/kernel/printk/printk.c
+++ linux-2.6/kernel/printk/printk.c
@@ -2227,11 +2227,14 @@ void register_console(struct console *ne
     struct console_cmdline *c;

     if (console_drivers)
-        for_each_console(bcon)
-            if (WARN(bcon == newcon,
-                    "console '%s%d' already registered\n",
-                    bcon->name, bcon->index))
+        for_each_console(bcon) {
+            /* not again */
+            if (bcon == newcon) {
+                printk(KERN_INFO "console '%s%d' already registered\n",
+                    bcon->name, bcon->index);
                 return;
+            }
+    }

     /*
      * before we register a new CON_BOOT console, make sure we don't

[-- Attachment #2: setup_early_console_x1_pa_symbol_before_earlcon.patch --]
[-- Type: text/x-patch, Size: 4105 bytes --]

Subject: [PATCH -v4] x86: Setup early console as early as possible in x86_start_kernel()

Analyze "console=uart8250,io,0x3f8,115200n8" in i386_start_kernel/x86_64_start_kernel,
and call setup_early_serial8250_console() to init early serial console.

Only can handle io port kind of 8250, because mmio need ioremap.

Use boot_params.hdr.version instead of adding another variable, Suggested by hpa.
Also need to apply this one after x86 memblock patchset.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 arch/x86/include/asm/setup.h |    2 ++
 arch/x86/kernel/head.c       |   26 ++++++++++++++++++++++++++
 arch/x86/kernel/head32.c     |    1 +
 arch/x86/kernel/head64.c     |    5 ++++-
 kernel/printk/printk.c       |   11 +++++++----
 5 files changed, 40 insertions(+), 5 deletions(-)

Index: linux-2.6/arch/x86/include/asm/setup.h
===================================================================
--- linux-2.6.orig/arch/x86/include/asm/setup.h
+++ linux-2.6/arch/x86/include/asm/setup.h
@@ -49,6 +49,8 @@ static inline void x86_acpi_override_fin
 #endif
 
 extern unsigned long saved_video_mode;
+int setup_early_serial8250_console(char *cmdline);
+void setup_early_console(void);
 
 extern void reserve_standard_io_resources(void);
 extern void i386_reserve_resources(void);
Index: linux-2.6/arch/x86/kernel/head.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head.c
+++ linux-2.6/arch/x86/kernel/head.c
@@ -69,3 +69,29 @@ void __init reserve_ebda_region(void)
 	/* reserve all memory between lowmem and the 1MB mark */
 	memblock_reserve(lowmem, 0x100000 - lowmem);
 }
+
+void __init setup_early_console(void)
+{
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+	char constr[64], *p, *q;
+
+	/* Can not handle mmio type 8250 uart yet, too early */
+	p = strstr(boot_command_line, "console=uart8250,io,");
+	if (!p)
+		p = strstr(boot_command_line, "console=uart,io,");
+	if (!p)
+		return;
+
+	p += 8;	/* sizeof "console=" */
+	q = strchr(p, ' ');
+	if ((q - p) >= sizeof(constr))
+		return;
+
+	memset(constr, 0, sizeof(constr));
+	memcpy(constr, p, q - p);
+
+	lockdep_init();
+
+	setup_early_serial8250_console(constr);
+#endif
+}
Index: linux-2.6/arch/x86/kernel/head32.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head32.c
+++ linux-2.6/arch/x86/kernel/head32.c
@@ -32,6 +32,7 @@ static void __init i386_default_early_se
 void __init i386_start_kernel(void)
 {
 	sanitize_boot_params(&boot_params);
+	setup_early_console();
 
 	/* Call the subarch specific early setup function */
 	switch (boot_params.hdr.hardware_subarch) {
Index: linux-2.6/arch/x86/kernel/head64.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head64.c
+++ linux-2.6/arch/x86/kernel/head64.c
@@ -166,6 +166,7 @@ void __init x86_64_start_kernel(char * r
 	load_idt((const struct desc_ptr *)&idt_descr);
 
 	copy_bootdata(__va(real_mode_data));
+	setup_early_console();
 
 	/*
 	 * Load microcode early on BSP.
@@ -187,8 +188,10 @@ void __init x86_64_start_kernel(char * r
 void __init x86_64_start_reservations(char *real_mode_data)
 {
 	/* version is always not zero if it is copied */
-	if (!boot_params.hdr.version)
+	if (!boot_params.hdr.version) {
 		copy_bootdata(__va(real_mode_data));
+		setup_early_console();
+	}
 
 	reserve_ebda_region();
 
Index: linux-2.6/kernel/printk/printk.c
===================================================================
--- linux-2.6.orig/kernel/printk/printk.c
+++ linux-2.6/kernel/printk/printk.c
@@ -2227,11 +2227,14 @@ void register_console(struct console *ne
 	struct console_cmdline *c;
 
 	if (console_drivers)
-		for_each_console(bcon)
-			if (WARN(bcon == newcon,
-					"console '%s%d' already registered\n",
-					bcon->name, bcon->index))
+		for_each_console(bcon) {
+			/* not again */
+			if (bcon == newcon) {
+				printk(KERN_INFO "console '%s%d' already registered\n",
+					bcon->name, bcon->index);
 				return;
+			}
+	}
 
 	/*
 	 * before we register a new CON_BOOT console, make sure we don't

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

[-- Attachment #1: Type: text/plain, Size: 5384 bytes --]

On Tue, Apr 29, 2014 at 1:41 PM, Rob Herring <robherring2@gmail.com> wrote:
> On Tue, Apr 29, 2014 at 1:22 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>>
>> You want to obsolete "console=uart,io,0x3f8,115200n8" ?
>>
>>  Let's check with Andrew. He suggested to use uart and uart8250 at that time.
>
> No, that is not what I'm saying. For the 2 callers of
> setup_early_serial8250_console which are crafting a console string
> from firmware data, they can and do use uart8250. I don't expect this
> mechanism for setting up early console to expand to other users. The
> whole point of this series is to allow any uart to be supported for
> earlycon. For anyone using the kernel command line, both uart and
> uart8250 are still supported.

That is confusing, why not keeping them consistent?

I posted one patch before about "early early console for x86", and it
is in my local tree
 for some time.support both "uart,io" and "uart8250,io".

Peter, Can you check that patch again?  --- updated version attached.
and inlined.

Thanks

Yinghai

Subject: [PATCH -v4] x86: Setup early console as early as possible in
x86_start_kernel()

Analyze "console=uart8250,io,0x3f8,115200n8" in
i386_start_kernel/x86_64_start_kernel,
and call setup_early_serial8250_console() to init early serial console.

Only can handle io port kind of 8250, because mmio need ioremap.

Use boot_params.hdr.version instead of adding another variable,
Suggested by hpa.
Also need to apply this one after x86 memblock patchset.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 arch/x86/include/asm/setup.h |    2 ++
 arch/x86/kernel/head.c       |   26 ++++++++++++++++++++++++++
 arch/x86/kernel/head32.c     |    1 +
 arch/x86/kernel/head64.c     |    5 ++++-
 kernel/printk/printk.c       |   11 +++++++----
 5 files changed, 40 insertions(+), 5 deletions(-)

Index: linux-2.6/arch/x86/include/asm/setup.h
===================================================================
--- linux-2.6.orig/arch/x86/include/asm/setup.h
+++ linux-2.6/arch/x86/include/asm/setup.h
@@ -49,6 +49,8 @@ static inline void x86_acpi_override_fin
 #endif

 extern unsigned long saved_video_mode;
+int setup_early_serial8250_console(char *cmdline);
+void setup_early_console(void);

 extern void reserve_standard_io_resources(void);
 extern void i386_reserve_resources(void);
Index: linux-2.6/arch/x86/kernel/head.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head.c
+++ linux-2.6/arch/x86/kernel/head.c
@@ -69,3 +69,29 @@ void __init reserve_ebda_region(void)
     /* reserve all memory between lowmem and the 1MB mark */
     memblock_reserve(lowmem, 0x100000 - lowmem);
 }
+
+void __init setup_early_console(void)
+{
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+    char constr[64], *p, *q;
+
+    /* Can not handle mmio type 8250 uart yet, too early */
+    p = strstr(boot_command_line, "console=uart8250,io,");
+    if (!p)
+        p = strstr(boot_command_line, "console=uart,io,");
+    if (!p)
+        return;
+
+    p += 8;    /* sizeof "console=" */
+    q = strchr(p, ' ');
+    if ((q - p) >= sizeof(constr))
+        return;
+
+    memset(constr, 0, sizeof(constr));
+    memcpy(constr, p, q - p);
+
+    lockdep_init();
+
+    setup_early_serial8250_console(constr);
+#endif
+}
Index: linux-2.6/arch/x86/kernel/head32.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head32.c
+++ linux-2.6/arch/x86/kernel/head32.c
@@ -32,6 +32,7 @@ static void __init i386_default_early_se
 void __init i386_start_kernel(void)
 {
     sanitize_boot_params(&boot_params);
+    setup_early_console();

     /* Call the subarch specific early setup function */
     switch (boot_params.hdr.hardware_subarch) {
Index: linux-2.6/arch/x86/kernel/head64.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head64.c
+++ linux-2.6/arch/x86/kernel/head64.c
@@ -166,6 +166,7 @@ void __init x86_64_start_kernel(char * r
     load_idt((const struct desc_ptr *)&idt_descr);

     copy_bootdata(__va(real_mode_data));
+    setup_early_console();

     /*
      * Load microcode early on BSP.
@@ -187,8 +188,10 @@ void __init x86_64_start_kernel(char * r
 void __init x86_64_start_reservations(char *real_mode_data)
 {
     /* version is always not zero if it is copied */
-    if (!boot_params.hdr.version)
+    if (!boot_params.hdr.version) {
         copy_bootdata(__va(real_mode_data));
+        setup_early_console();
+    }

     reserve_ebda_region();

Index: linux-2.6/kernel/printk/printk.c
===================================================================
--- linux-2.6.orig/kernel/printk/printk.c
+++ linux-2.6/kernel/printk/printk.c
@@ -2227,11 +2227,14 @@ void register_console(struct console *ne
     struct console_cmdline *c;

     if (console_drivers)
-        for_each_console(bcon)
-            if (WARN(bcon == newcon,
-                    "console '%s%d' already registered\n",
-                    bcon->name, bcon->index))
+        for_each_console(bcon) {
+            /* not again */
+            if (bcon == newcon) {
+                printk(KERN_INFO "console '%s%d' already registered\n",
+                    bcon->name, bcon->index);
                 return;
+            }
+    }

     /*
      * before we register a new CON_BOOT console, make sure we don't

[-- Attachment #2: setup_early_console_x1_pa_symbol_before_earlcon.patch --]
[-- Type: text/x-patch, Size: 4105 bytes --]

Subject: [PATCH -v4] x86: Setup early console as early as possible in x86_start_kernel()

Analyze "console=uart8250,io,0x3f8,115200n8" in i386_start_kernel/x86_64_start_kernel,
and call setup_early_serial8250_console() to init early serial console.

Only can handle io port kind of 8250, because mmio need ioremap.

Use boot_params.hdr.version instead of adding another variable, Suggested by hpa.
Also need to apply this one after x86 memblock patchset.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 arch/x86/include/asm/setup.h |    2 ++
 arch/x86/kernel/head.c       |   26 ++++++++++++++++++++++++++
 arch/x86/kernel/head32.c     |    1 +
 arch/x86/kernel/head64.c     |    5 ++++-
 kernel/printk/printk.c       |   11 +++++++----
 5 files changed, 40 insertions(+), 5 deletions(-)

Index: linux-2.6/arch/x86/include/asm/setup.h
===================================================================
--- linux-2.6.orig/arch/x86/include/asm/setup.h
+++ linux-2.6/arch/x86/include/asm/setup.h
@@ -49,6 +49,8 @@ static inline void x86_acpi_override_fin
 #endif
 
 extern unsigned long saved_video_mode;
+int setup_early_serial8250_console(char *cmdline);
+void setup_early_console(void);
 
 extern void reserve_standard_io_resources(void);
 extern void i386_reserve_resources(void);
Index: linux-2.6/arch/x86/kernel/head.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head.c
+++ linux-2.6/arch/x86/kernel/head.c
@@ -69,3 +69,29 @@ void __init reserve_ebda_region(void)
 	/* reserve all memory between lowmem and the 1MB mark */
 	memblock_reserve(lowmem, 0x100000 - lowmem);
 }
+
+void __init setup_early_console(void)
+{
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+	char constr[64], *p, *q;
+
+	/* Can not handle mmio type 8250 uart yet, too early */
+	p = strstr(boot_command_line, "console=uart8250,io,");
+	if (!p)
+		p = strstr(boot_command_line, "console=uart,io,");
+	if (!p)
+		return;
+
+	p += 8;	/* sizeof "console=" */
+	q = strchr(p, ' ');
+	if ((q - p) >= sizeof(constr))
+		return;
+
+	memset(constr, 0, sizeof(constr));
+	memcpy(constr, p, q - p);
+
+	lockdep_init();
+
+	setup_early_serial8250_console(constr);
+#endif
+}
Index: linux-2.6/arch/x86/kernel/head32.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head32.c
+++ linux-2.6/arch/x86/kernel/head32.c
@@ -32,6 +32,7 @@ static void __init i386_default_early_se
 void __init i386_start_kernel(void)
 {
 	sanitize_boot_params(&boot_params);
+	setup_early_console();
 
 	/* Call the subarch specific early setup function */
 	switch (boot_params.hdr.hardware_subarch) {
Index: linux-2.6/arch/x86/kernel/head64.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head64.c
+++ linux-2.6/arch/x86/kernel/head64.c
@@ -166,6 +166,7 @@ void __init x86_64_start_kernel(char * r
 	load_idt((const struct desc_ptr *)&idt_descr);
 
 	copy_bootdata(__va(real_mode_data));
+	setup_early_console();
 
 	/*
 	 * Load microcode early on BSP.
@@ -187,8 +188,10 @@ void __init x86_64_start_kernel(char * r
 void __init x86_64_start_reservations(char *real_mode_data)
 {
 	/* version is always not zero if it is copied */
-	if (!boot_params.hdr.version)
+	if (!boot_params.hdr.version) {
 		copy_bootdata(__va(real_mode_data));
+		setup_early_console();
+	}
 
 	reserve_ebda_region();
 
Index: linux-2.6/kernel/printk/printk.c
===================================================================
--- linux-2.6.orig/kernel/printk/printk.c
+++ linux-2.6/kernel/printk/printk.c
@@ -2227,11 +2227,14 @@ void register_console(struct console *ne
 	struct console_cmdline *c;
 
 	if (console_drivers)
-		for_each_console(bcon)
-			if (WARN(bcon == newcon,
-					"console '%s%d' already registered\n",
-					bcon->name, bcon->index))
+		for_each_console(bcon) {
+			/* not again */
+			if (bcon == newcon) {
+				printk(KERN_INFO "console '%s%d' already registered\n",
+					bcon->name, bcon->index);
 				return;
+			}
+	}
 
 	/*
 	 * before we register a new CON_BOOT console, make sure we don't

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Tue, Apr 29, 2014 at 1:41 PM, Rob Herring <robherring2@gmail.com> wrote:
> On Tue, Apr 29, 2014 at 1:22 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>>
>> You want to obsolete "console=uart,io,0x3f8,115200n8" ?
>>
>>  Let's check with Andrew. He suggested to use uart and uart8250 at that time.
>
> No, that is not what I'm saying. For the 2 callers of
> setup_early_serial8250_console which are crafting a console string
> from firmware data, they can and do use uart8250. I don't expect this
> mechanism for setting up early console to expand to other users. The
> whole point of this series is to allow any uart to be supported for
> earlycon. For anyone using the kernel command line, both uart and
> uart8250 are still supported.

That is confusing, why not keeping them consistent?

I posted one patch before about "early early console for x86", and it
is in my local tree
 for some time.support both "uart,io" and "uart8250,io".

Peter, Can you check that patch again?  --- updated version attached.
and inlined.

Thanks

Yinghai

Subject: [PATCH -v4] x86: Setup early console as early as possible in
x86_start_kernel()

Analyze "console=uart8250,io,0x3f8,115200n8" in
i386_start_kernel/x86_64_start_kernel,
and call setup_early_serial8250_console() to init early serial console.

Only can handle io port kind of 8250, because mmio need ioremap.

Use boot_params.hdr.version instead of adding another variable,
Suggested by hpa.
Also need to apply this one after x86 memblock patchset.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 arch/x86/include/asm/setup.h |    2 ++
 arch/x86/kernel/head.c       |   26 ++++++++++++++++++++++++++
 arch/x86/kernel/head32.c     |    1 +
 arch/x86/kernel/head64.c     |    5 ++++-
 kernel/printk/printk.c       |   11 +++++++----
 5 files changed, 40 insertions(+), 5 deletions(-)

Index: linux-2.6/arch/x86/include/asm/setup.h
===================================================================
--- linux-2.6.orig/arch/x86/include/asm/setup.h
+++ linux-2.6/arch/x86/include/asm/setup.h
@@ -49,6 +49,8 @@ static inline void x86_acpi_override_fin
 #endif

 extern unsigned long saved_video_mode;
+int setup_early_serial8250_console(char *cmdline);
+void setup_early_console(void);

 extern void reserve_standard_io_resources(void);
 extern void i386_reserve_resources(void);
Index: linux-2.6/arch/x86/kernel/head.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head.c
+++ linux-2.6/arch/x86/kernel/head.c
@@ -69,3 +69,29 @@ void __init reserve_ebda_region(void)
     /* reserve all memory between lowmem and the 1MB mark */
     memblock_reserve(lowmem, 0x100000 - lowmem);
 }
+
+void __init setup_early_console(void)
+{
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+    char constr[64], *p, *q;
+
+    /* Can not handle mmio type 8250 uart yet, too early */
+    p = strstr(boot_command_line, "console=uart8250,io,");
+    if (!p)
+        p = strstr(boot_command_line, "console=uart,io,");
+    if (!p)
+        return;
+
+    p += 8;    /* sizeof "console=" */
+    q = strchr(p, ' ');
+    if ((q - p) >= sizeof(constr))
+        return;
+
+    memset(constr, 0, sizeof(constr));
+    memcpy(constr, p, q - p);
+
+    lockdep_init();
+
+    setup_early_serial8250_console(constr);
+#endif
+}
Index: linux-2.6/arch/x86/kernel/head32.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head32.c
+++ linux-2.6/arch/x86/kernel/head32.c
@@ -32,6 +32,7 @@ static void __init i386_default_early_se
 void __init i386_start_kernel(void)
 {
     sanitize_boot_params(&boot_params);
+    setup_early_console();

     /* Call the subarch specific early setup function */
     switch (boot_params.hdr.hardware_subarch) {
Index: linux-2.6/arch/x86/kernel/head64.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/head64.c
+++ linux-2.6/arch/x86/kernel/head64.c
@@ -166,6 +166,7 @@ void __init x86_64_start_kernel(char * r
     load_idt((const struct desc_ptr *)&idt_descr);

     copy_bootdata(__va(real_mode_data));
+    setup_early_console();

     /*
      * Load microcode early on BSP.
@@ -187,8 +188,10 @@ void __init x86_64_start_kernel(char * r
 void __init x86_64_start_reservations(char *real_mode_data)
 {
     /* version is always not zero if it is copied */
-    if (!boot_params.hdr.version)
+    if (!boot_params.hdr.version) {
         copy_bootdata(__va(real_mode_data));
+        setup_early_console();
+    }

     reserve_ebda_region();

Index: linux-2.6/kernel/printk/printk.c
===================================================================
--- linux-2.6.orig/kernel/printk/printk.c
+++ linux-2.6/kernel/printk/printk.c
@@ -2227,11 +2227,14 @@ void register_console(struct console *ne
     struct console_cmdline *c;

     if (console_drivers)
-        for_each_console(bcon)
-            if (WARN(bcon == newcon,
-                    "console '%s%d' already registered\n",
-                    bcon->name, bcon->index))
+        for_each_console(bcon) {
+            /* not again */
+            if (bcon == newcon) {
+                printk(KERN_INFO "console '%s%d' already registered\n",
+                    bcon->name, bcon->index);
                 return;
+            }
+    }

     /*
      * before we register a new CON_BOOT console, make sure we don't
-------------- next part --------------
A non-text attachment was scrubbed...
Name: setup_early_console_x1_pa_symbol_before_earlcon.patch
Type: text/x-patch
Size: 4105 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20140429/f527c861/attachment.bin>

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Greg Kroah-Hartman]

On Mon, Apr 28, 2014 at 06:20:53PM -0500, Rob Herring wrote:
> On Sat, Apr 26, 2014 at 1:19 AM, Yinghai Lu <yinghai@kernel.org> wrote:
> > On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
> >> From: Rob Herring <robh@kernel.org>
> >>
> >> With the generic earlycon infrastructure in place, convert the 8250
> >> early console to use it.
> >>
> >> Signed-off-by: Rob Herring <robh@kernel.org>
> >> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> >> Cc: Jiri Slaby <jslaby@suse.cz>
> >> ---
> >>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
> >>  drivers/tty/serial/8250/Kconfig      |   1 +
> >>  2 files changed, 16 insertions(+), 123 deletions(-)
> >
> > Hi Greg, Rob
> >
> > This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
> > No early console and regular console anymore.
> >
> > It should produce "early con and regular con".
> 
> This is what I get for running checkpatch and converting
> simple_strtoul to kstrto* which are not so equivalent. kstrto* will
> not convert things such as 115200n8 to a number.
> 
> Greg, Do you want a fix or for me to respin the series? The fix looks like this:

As this is in my tree now (right?), I need a fix to apply to it.

thanks,

greg k-h

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Greg Kroah-Hartman]

On Mon, Apr 28, 2014 at 06:20:53PM -0500, Rob Herring wrote:
> On Sat, Apr 26, 2014 at 1:19 AM, Yinghai Lu <yinghai@kernel.org> wrote:
> > On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
> >> From: Rob Herring <robh@kernel.org>
> >>
> >> With the generic earlycon infrastructure in place, convert the 8250
> >> early console to use it.
> >>
> >> Signed-off-by: Rob Herring <robh@kernel.org>
> >> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> >> Cc: Jiri Slaby <jslaby@suse.cz>
> >> ---
> >>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
> >>  drivers/tty/serial/8250/Kconfig      |   1 +
> >>  2 files changed, 16 insertions(+), 123 deletions(-)
> >
> > Hi Greg, Rob
> >
> > This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
> > No early console and regular console anymore.
> >
> > It should produce "early con and regular con".
> 
> This is what I get for running checkpatch and converting
> simple_strtoul to kstrto* which are not so equivalent. kstrto* will
> not convert things such as 115200n8 to a number.
> 
> Greg, Do you want a fix or for me to respin the series? The fix looks like this:

As this is in my tree now (right?), I need a fix to apply to it.

thanks,

greg k-h

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Greg Kroah-Hartman]

On Mon, Apr 28, 2014 at 06:20:53PM -0500, Rob Herring wrote:
> On Sat, Apr 26, 2014 at 1:19 AM, Yinghai Lu <yinghai@kernel.org> wrote:
> > On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
> >> From: Rob Herring <robh@kernel.org>
> >>
> >> With the generic earlycon infrastructure in place, convert the 8250
> >> early console to use it.
> >>
> >> Signed-off-by: Rob Herring <robh@kernel.org>
> >> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> >> Cc: Jiri Slaby <jslaby@suse.cz>
> >> ---
> >>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
> >>  drivers/tty/serial/8250/Kconfig      |   1 +
> >>  2 files changed, 16 insertions(+), 123 deletions(-)
> >
> > Hi Greg, Rob
> >
> > This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
> > No early console and regular console anymore.
> >
> > It should produce "early con and regular con".
> 
> This is what I get for running checkpatch and converting
> simple_strtoul to kstrto* which are not so equivalent. kstrto* will
> not convert things such as 115200n8 to a number.
> 
> Greg, Do you want a fix or for me to respin the series? The fix looks like this:

As this is in my tree now (right?), I need a fix to apply to it.

thanks,

greg k-h

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Greg Kroah-Hartman]

On Sat, May 03, 2014 at 06:07:31PM -0400, Greg Kroah-Hartman wrote:
> On Mon, Apr 28, 2014 at 06:20:53PM -0500, Rob Herring wrote:
> > On Sat, Apr 26, 2014 at 1:19 AM, Yinghai Lu <yinghai@kernel.org> wrote:
> > > On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
> > >> From: Rob Herring <robh@kernel.org>
> > >>
> > >> With the generic earlycon infrastructure in place, convert the 8250
> > >> early console to use it.
> > >>
> > >> Signed-off-by: Rob Herring <robh@kernel.org>
> > >> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > >> Cc: Jiri Slaby <jslaby@suse.cz>
> > >> ---
> > >>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
> > >>  drivers/tty/serial/8250/Kconfig      |   1 +
> > >>  2 files changed, 16 insertions(+), 123 deletions(-)
> > >
> > > Hi Greg, Rob
> > >
> > > This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
> > > No early console and regular console anymore.
> > >
> > > It should produce "early con and regular con".
> > 
> > This is what I get for running checkpatch and converting
> > simple_strtoul to kstrto* which are not so equivalent. kstrto* will
> > not convert things such as 115200n8 to a number.
> > 
> > Greg, Do you want a fix or for me to respin the series? The fix looks like this:
> 
> As this is in my tree now (right?), I need a fix to apply to it.

Nevermind, you already sent it...

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Greg Kroah-Hartman]

On Sat, May 03, 2014 at 06:07:31PM -0400, Greg Kroah-Hartman wrote:
> On Mon, Apr 28, 2014 at 06:20:53PM -0500, Rob Herring wrote:
> > On Sat, Apr 26, 2014 at 1:19 AM, Yinghai Lu <yinghai@kernel.org> wrote:
> > > On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
> > >> From: Rob Herring <robh@kernel.org>
> > >>
> > >> With the generic earlycon infrastructure in place, convert the 8250
> > >> early console to use it.
> > >>
> > >> Signed-off-by: Rob Herring <robh@kernel.org>
> > >> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > >> Cc: Jiri Slaby <jslaby@suse.cz>
> > >> ---
> > >>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
> > >>  drivers/tty/serial/8250/Kconfig      |   1 +
> > >>  2 files changed, 16 insertions(+), 123 deletions(-)
> > >
> > > Hi Greg, Rob
> > >
> > > This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
> > > No early console and regular console anymore.
> > >
> > > It should produce "early con and regular con".
> > 
> > This is what I get for running checkpatch and converting
> > simple_strtoul to kstrto* which are not so equivalent. kstrto* will
> > not convert things such as 115200n8 to a number.
> > 
> > Greg, Do you want a fix or for me to respin the series? The fix looks like this:
> 
> As this is in my tree now (right?), I need a fix to apply to it.

Nevermind, you already sent it...

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Greg Kroah-Hartman]

On Sat, May 03, 2014 at 06:07:31PM -0400, Greg Kroah-Hartman wrote:
> On Mon, Apr 28, 2014 at 06:20:53PM -0500, Rob Herring wrote:
> > On Sat, Apr 26, 2014 at 1:19 AM, Yinghai Lu <yinghai@kernel.org> wrote:
> > > On Fri, Apr 18, 2014 at 3:19 PM, Rob Herring <robherring2@gmail.com> wrote:
> > >> From: Rob Herring <robh@kernel.org>
> > >>
> > >> With the generic earlycon infrastructure in place, convert the 8250
> > >> early console to use it.
> > >>
> > >> Signed-off-by: Rob Herring <robh@kernel.org>
> > >> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > >> Cc: Jiri Slaby <jslaby@suse.cz>
> > >> ---
> > >>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
> > >>  drivers/tty/serial/8250/Kconfig      |   1 +
> > >>  2 files changed, 16 insertions(+), 123 deletions(-)
> > >
> > > Hi Greg, Rob
> > >
> > > This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
> > > No early console and regular console anymore.
> > >
> > > It should produce "early con and regular con".
> > 
> > This is what I get for running checkpatch and converting
> > simple_strtoul to kstrto* which are not so equivalent. kstrto* will
> > not convert things such as 115200n8 to a number.
> > 
> > Greg, Do you want a fix or for me to respin the series? The fix looks like this:
> 
> As this is in my tree now (right?), I need a fix to apply to it.

Nevermind, you already sent it...

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Tony Luck]

On Sat, May 3, 2014 at 3:16 PM, Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>> > >>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>> > >>  drivers/tty/serial/8250/Kconfig      |   1 +
>> > >>  2 files changed, 16 insertions(+), 123 deletions(-)
>> > >
>> > > Hi Greg, Rob
>> > >
>> > > This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
>> > > No early console and regular console anymore.
>> > >
>> > > It should produce "early con and regular con".
>> >
>> > This is what I get for running checkpatch and converting
>> > simple_strtoul to kstrto* which are not so equivalent. kstrto* will
>> > not convert things such as 115200n8 to a number.
>> >
>> > Greg, Do you want a fix or for me to respin the series? The fix looks like this:
>>
>> As this is in my tree now (right?), I need a fix to apply to it.
>
> Nevermind, you already sent it...

Linus' tree (HEAD=963649d735c8) is spitting out all sorts of garbage
on the serial console - as if the baud rate is being periodically set
to something weird, and then back to 112500.  I see over a dozen
blocks of junk interspersed with good output.

This in on ia64 with "console=uart,io,0x3f8" on the command line.

git bisect pointed me here:

d2fd6810a823bcde1ee232668f5689837aafa772 is first bad commit
commit d2fd6810a823bcde1ee232668f5689837aafa772
Author: Rob Herring <robh@kernel.org>
Date:   Fri Apr 18 17:19:56 2014 -0500

    tty/serial: convert 8250 to generic earlycon

-Tony

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Tony Luck]

On Sat, May 3, 2014 at 3:16 PM, Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>> > >>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>> > >>  drivers/tty/serial/8250/Kconfig      |   1 +
>> > >>  2 files changed, 16 insertions(+), 123 deletions(-)
>> > >
>> > > Hi Greg, Rob
>> > >
>> > > This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
>> > > No early console and regular console anymore.
>> > >
>> > > It should produce "early con and regular con".
>> >
>> > This is what I get for running checkpatch and converting
>> > simple_strtoul to kstrto* which are not so equivalent. kstrto* will
>> > not convert things such as 115200n8 to a number.
>> >
>> > Greg, Do you want a fix or for me to respin the series? The fix looks like this:
>>
>> As this is in my tree now (right?), I need a fix to apply to it.
>
> Nevermind, you already sent it...

Linus' tree (HEAD=963649d735c8) is spitting out all sorts of garbage
on the serial console - as if the baud rate is being periodically set
to something weird, and then back to 112500.  I see over a dozen
blocks of junk interspersed with good output.

This in on ia64 with "console=uart,io,0x3f8" on the command line.

git bisect pointed me here:

d2fd6810a823bcde1ee232668f5689837aafa772 is first bad commit
commit d2fd6810a823bcde1ee232668f5689837aafa772
Author: Rob Herring <robh@kernel.org>
Date:   Fri Apr 18 17:19:56 2014 -0500

    tty/serial: convert 8250 to generic earlycon

-Tony

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Tony Luck]

On Sat, May 3, 2014 at 3:16 PM, Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>> > >>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>> > >>  drivers/tty/serial/8250/Kconfig      |   1 +
>> > >>  2 files changed, 16 insertions(+), 123 deletions(-)
>> > >
>> > > Hi Greg, Rob
>> > >
>> > > This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
>> > > No early console and regular console anymore.
>> > >
>> > > It should produce "early con and regular con".
>> >
>> > This is what I get for running checkpatch and converting
>> > simple_strtoul to kstrto* which are not so equivalent. kstrto* will
>> > not convert things such as 115200n8 to a number.
>> >
>> > Greg, Do you want a fix or for me to respin the series? The fix looks like this:
>>
>> As this is in my tree now (right?), I need a fix to apply to it.
>
> Nevermind, you already sent it...

Linus' tree (HEAD=963649d735c8) is spitting out all sorts of garbage
on the serial console - as if the baud rate is being periodically set
to something weird, and then back to 112500.  I see over a dozen
blocks of junk interspersed with good output.

This in on ia64 with "console=uart,io,0x3f8" on the command line.

git bisect pointed me here:

d2fd6810a823bcde1ee232668f5689837aafa772 is first bad commit
commit d2fd6810a823bcde1ee232668f5689837aafa772
Author: Rob Herring <robh@kernel.org>
Date:   Fri Apr 18 17:19:56 2014 -0500

    tty/serial: convert 8250 to generic earlycon

-Tony

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Tony Luck]

On Mon, Jun 9, 2014 at 3:25 PM, Tony Luck <tony.luck@gmail.com> wrote:
> Linus' tree (HEAD=963649d735c8) is spitting out all sorts of garbage
> on the serial console - as if the baud rate is being periodically set
> to something weird, and then back to 112500.  I see over a dozen
> blocks of junk interspersed with good output.

Ah - it seems that I need to be more specific on the cmdline

     console=uart8250,io,0x3f8,115200

makes all the garbage disappear.

Do I need to update: Documentation/ia64/serial.txt
which has the example of "console=uart,io,0x3f8"?

-Tony

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Tony Luck]

On Mon, Jun 9, 2014 at 3:25 PM, Tony Luck <tony.luck@gmail.com> wrote:
> Linus' tree (HEAD=963649d735c8) is spitting out all sorts of garbage
> on the serial console - as if the baud rate is being periodically set
> to something weird, and then back to 112500.  I see over a dozen
> blocks of junk interspersed with good output.

Ah - it seems that I need to be more specific on the cmdline

     console=uart8250,io,0x3f8,115200

makes all the garbage disappear.

Do I need to update: Documentation/ia64/serial.txt
which has the example of "console=uart,io,0x3f8"?

-Tony

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Tony Luck]

On Mon, Jun 9, 2014 at 3:25 PM, Tony Luck <tony.luck@gmail.com> wrote:
> Linus' tree (HEAD=963649d735c8) is spitting out all sorts of garbage
> on the serial console - as if the baud rate is being periodically set
> to something weird, and then back to 112500.  I see over a dozen
> blocks of junk interspersed with good output.

Ah - it seems that I need to be more specific on the cmdline

     console=uart8250,io,0x3f8,115200

makes all the garbage disappear.

Do I need to update: Documentation/ia64/serial.txt
which has the example of "console=uart,io,0x3f8"?

-Tony

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Mon, Jun 9, 2014 at 5:25 PM, Tony Luck <tony.luck@gmail.com> wrote:
> On Sat, May 3, 2014 at 3:16 PM, Greg Kroah-Hartman
> <gregkh@linuxfoundation.org> wrote:
>>> > >>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>>> > >>  drivers/tty/serial/8250/Kconfig      |   1 +
>>> > >>  2 files changed, 16 insertions(+), 123 deletions(-)
>>> > >
>>> > > Hi Greg, Rob
>>> > >
>>> > > This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
>>> > > No early console and regular console anymore.
>>> > >
>>> > > It should produce "early con and regular con".
>>> >
>>> > This is what I get for running checkpatch and converting
>>> > simple_strtoul to kstrto* which are not so equivalent. kstrto* will
>>> > not convert things such as 115200n8 to a number.
>>> >
>>> > Greg, Do you want a fix or for me to respin the series? The fix looks like this:
>>>
>>> As this is in my tree now (right?), I need a fix to apply to it.
>>
>> Nevermind, you already sent it...
>
> Linus' tree (HEAD=963649d735c8) is spitting out all sorts of garbage
> on the serial console - as if the baud rate is being periodically set
> to something weird, and then back to 112500.  I see over a dozen
> blocks of junk interspersed with good output.

Is there any correlation of the garbage to printks of console enabled messages?

>
> This in on ia64 with "console=uart,io,0x3f8" on the command line.

Does "console=ttyS0,115200" or "console=uart,io,0x3f8,115200" work?

You will need this fix for the 2nd one to work:

commit e26f1db9b8d74617519e50b41749900d0a257406
Author: Rob Herring <robh@kernel.org>
Date:   Wed Apr 30 19:48:29 2014 -0500

    tty/serial: fix generic earlycon option parsing

Rob

>
> git bisect pointed me here:
>
> d2fd6810a823bcde1ee232668f5689837aafa772 is first bad commit
> commit d2fd6810a823bcde1ee232668f5689837aafa772
> Author: Rob Herring <robh@kernel.org>
> Date:   Fri Apr 18 17:19:56 2014 -0500
>
>     tty/serial: convert 8250 to generic earlycon
>
> -Tony

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Mon, Jun 9, 2014 at 5:25 PM, Tony Luck <tony.luck@gmail.com> wrote:
> On Sat, May 3, 2014 at 3:16 PM, Greg Kroah-Hartman
> <gregkh@linuxfoundation.org> wrote:
>>> > >>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>>> > >>  drivers/tty/serial/8250/Kconfig      |   1 +
>>> > >>  2 files changed, 16 insertions(+), 123 deletions(-)
>>> > >
>>> > > Hi Greg, Rob
>>> > >
>>> > > This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
>>> > > No early console and regular console anymore.
>>> > >
>>> > > It should produce "early con and regular con".
>>> >
>>> > This is what I get for running checkpatch and converting
>>> > simple_strtoul to kstrto* which are not so equivalent. kstrto* will
>>> > not convert things such as 115200n8 to a number.
>>> >
>>> > Greg, Do you want a fix or for me to respin the series? The fix looks like this:
>>>
>>> As this is in my tree now (right?), I need a fix to apply to it.
>>
>> Nevermind, you already sent it...
>
> Linus' tree (HEAD=963649d735c8) is spitting out all sorts of garbage
> on the serial console - as if the baud rate is being periodically set
> to something weird, and then back to 112500.  I see over a dozen
> blocks of junk interspersed with good output.

Is there any correlation of the garbage to printks of console enabled messages?

>
> This in on ia64 with "console=uart,io,0x3f8" on the command line.

Does "console=ttyS0,115200" or "console=uart,io,0x3f8,115200" work?

You will need this fix for the 2nd one to work:

commit e26f1db9b8d74617519e50b41749900d0a257406
Author: Rob Herring <robh@kernel.org>
Date:   Wed Apr 30 19:48:29 2014 -0500

    tty/serial: fix generic earlycon option parsing

Rob

>
> git bisect pointed me here:
>
> d2fd6810a823bcde1ee232668f5689837aafa772 is first bad commit
> commit d2fd6810a823bcde1ee232668f5689837aafa772
> Author: Rob Herring <robh@kernel.org>
> Date:   Fri Apr 18 17:19:56 2014 -0500
>
>     tty/serial: convert 8250 to generic earlycon
>
> -Tony

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Mon, Jun 9, 2014 at 5:25 PM, Tony Luck <tony.luck@gmail.com> wrote:
> On Sat, May 3, 2014 at 3:16 PM, Greg Kroah-Hartman
> <gregkh@linuxfoundation.org> wrote:
>>> > >>  drivers/tty/serial/8250/8250_early.c | 138 ++++-------------------------------
>>> > >>  drivers/tty/serial/8250/Kconfig      |   1 +
>>> > >>  2 files changed, 16 insertions(+), 123 deletions(-)
>>> > >
>>> > > Hi Greg, Rob
>>> > >
>>> > > This one in tty-next breaks booting: "console=uart8250,io,0x3f8,115200".
>>> > > No early console and regular console anymore.
>>> > >
>>> > > It should produce "early con and regular con".
>>> >
>>> > This is what I get for running checkpatch and converting
>>> > simple_strtoul to kstrto* which are not so equivalent. kstrto* will
>>> > not convert things such as 115200n8 to a number.
>>> >
>>> > Greg, Do you want a fix or for me to respin the series? The fix looks like this:
>>>
>>> As this is in my tree now (right?), I need a fix to apply to it.
>>
>> Nevermind, you already sent it...
>
> Linus' tree (HEAD=963649d735c8) is spitting out all sorts of garbage
> on the serial console - as if the baud rate is being periodically set
> to something weird, and then back to 112500.  I see over a dozen
> blocks of junk interspersed with good output.

Is there any correlation of the garbage to printks of console enabled messages?

>
> This in on ia64 with "console=uart,io,0x3f8" on the command line.

Does "console=ttyS0,115200" or "console=uart,io,0x3f8,115200" work?

You will need this fix for the 2nd one to work:

commit e26f1db9b8d74617519e50b41749900d0a257406
Author: Rob Herring <robh@kernel.org>
Date:   Wed Apr 30 19:48:29 2014 -0500

    tty/serial: fix generic earlycon option parsing

Rob

>
> git bisect pointed me here:
>
> d2fd6810a823bcde1ee232668f5689837aafa772 is first bad commit
> commit d2fd6810a823bcde1ee232668f5689837aafa772
> Author: Rob Herring <robh@kernel.org>
> Date:   Fri Apr 18 17:19:56 2014 -0500
>
>     tty/serial: convert 8250 to generic earlycon
>
> -Tony

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Mon, Jun 9, 2014 at 5:35 PM, Tony Luck <tony.luck@gmail.com> wrote:
> On Mon, Jun 9, 2014 at 3:25 PM, Tony Luck <tony.luck@gmail.com> wrote:
>> Linus' tree (HEAD=963649d735c8) is spitting out all sorts of garbage
>> on the serial console - as if the baud rate is being periodically set
>> to something weird, and then back to 112500.  I see over a dozen
>> blocks of junk interspersed with good output.
>
> Ah - it seems that I need to be more specific on the cmdline
>
>      console=uart8250,io,0x3f8,115200
>
> makes all the garbage disappear.
>
> Do I need to update: Documentation/ia64/serial.txt
> which has the example of "console=uart,io,0x3f8"?

It should do auto detect of the baud-rate if it is not specified which
for 8250 is just reading the baud-rate divider and calculating the
baud-rate using the uart clock. It should just reprogram the divider
with the same divider value. I don't see anything obvious why this
would have broken.

Rob

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Mon, Jun 9, 2014 at 5:35 PM, Tony Luck <tony.luck@gmail.com> wrote:
> On Mon, Jun 9, 2014 at 3:25 PM, Tony Luck <tony.luck@gmail.com> wrote:
>> Linus' tree (HEAD=963649d735c8) is spitting out all sorts of garbage
>> on the serial console - as if the baud rate is being periodically set
>> to something weird, and then back to 112500.  I see over a dozen
>> blocks of junk interspersed with good output.
>
> Ah - it seems that I need to be more specific on the cmdline
>
>      console=uart8250,io,0x3f8,115200
>
> makes all the garbage disappear.
>
> Do I need to update: Documentation/ia64/serial.txt
> which has the example of "console=uart,io,0x3f8"?

It should do auto detect of the baud-rate if it is not specified which
for 8250 is just reading the baud-rate divider and calculating the
baud-rate using the uart clock. It should just reprogram the divider
with the same divider value. I don't see anything obvious why this
would have broken.

Rob

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Mon, Jun 9, 2014 at 5:35 PM, Tony Luck <tony.luck@gmail.com> wrote:
> On Mon, Jun 9, 2014 at 3:25 PM, Tony Luck <tony.luck@gmail.com> wrote:
>> Linus' tree (HEAD=963649d735c8) is spitting out all sorts of garbage
>> on the serial console - as if the baud rate is being periodically set
>> to something weird, and then back to 112500.  I see over a dozen
>> blocks of junk interspersed with good output.
>
> Ah - it seems that I need to be more specific on the cmdline
>
>      console=uart8250,io,0x3f8,115200
>
> makes all the garbage disappear.
>
> Do I need to update: Documentation/ia64/serial.txt
> which has the example of "console=uart,io,0x3f8"?

It should do auto detect of the baud-rate if it is not specified which
for 8250 is just reading the baud-rate divider and calculating the
baud-rate using the uart clock. It should just reprogram the divider
with the same divider value. I don't see anything obvious why this
would have broken.

Rob

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Tony Luck]

On Mon, Jun 9, 2014 at 4:18 PM, Rob Herring <robherring2@gmail.com> wrote:
> It should do auto detect of the baud-rate if it is not specified which
> for 8250 is just reading the baud-rate divider and calculating the
> baud-rate using the uart clock. It should just reprogram the divider
> with the same divider value. I don't see anything obvious why this
> would have broken.

Something very weird is happening.  Output is good so long as I put the
trailing ",115200" on the command line.

But I made early_serial8250_setup() printk() the return value it got
from probe_baud() - in case is was somehow getting 115201 or some
other silly value ... nope. Exactly 115200.

I also can't explain why the "noise" comes and goes a dozen
times during boot,

Does some other place in the kernel look at the "uart..." command
line argument?

-Tony

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Tony Luck]

On Mon, Jun 9, 2014 at 4:18 PM, Rob Herring <robherring2@gmail.com> wrote:
> It should do auto detect of the baud-rate if it is not specified which
> for 8250 is just reading the baud-rate divider and calculating the
> baud-rate using the uart clock. It should just reprogram the divider
> with the same divider value. I don't see anything obvious why this
> would have broken.

Something very weird is happening.  Output is good so long as I put the
trailing ",115200" on the command line.

But I made early_serial8250_setup() printk() the return value it got
from probe_baud() - in case is was somehow getting 115201 or some
other silly value ... nope. Exactly 115200.

I also can't explain why the "noise" comes and goes a dozen
times during boot,

Does some other place in the kernel look at the "uart..." command
line argument?

-Tony

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Tony Luck]

On Mon, Jun 9, 2014 at 4:18 PM, Rob Herring <robherring2@gmail.com> wrote:
> It should do auto detect of the baud-rate if it is not specified which
> for 8250 is just reading the baud-rate divider and calculating the
> baud-rate using the uart clock. It should just reprogram the divider
> with the same divider value. I don't see anything obvious why this
> would have broken.

Something very weird is happening.  Output is good so long as I put the
trailing ",115200" on the command line.

But I made early_serial8250_setup() printk() the return value it got
from probe_baud() - in case is was somehow getting 115201 or some
other silly value ... nope. Exactly 115200.

I also can't explain why the "noise" comes and goes a dozen
times during boot,

Does some other place in the kernel look at the "uart..." command
line argument?

-Tony

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Tue, Jun 10, 2014 at 3:52 PM, Tony Luck <tony.luck@gmail.com> wrote:
> On Mon, Jun 9, 2014 at 4:18 PM, Rob Herring <robherring2@gmail.com> wrote:
>> It should do auto detect of the baud-rate if it is not specified which
>> for 8250 is just reading the baud-rate divider and calculating the
>> baud-rate using the uart clock. It should just reprogram the divider
>> with the same divider value. I don't see anything obvious why this
>> would have broken.
>
> Something very weird is happening.  Output is good so long as I put the
> trailing ",115200" on the command line.
>
> But I made early_serial8250_setup() printk() the return value it got
> from probe_baud() - in case is was somehow getting 115201 or some
> other silly value ... nope. Exactly 115200.
>
> I also can't explain why the "noise" comes and goes a dozen
> times during boot,
>
> Does some other place in the kernel look at the "uart..." command
> line argument?

Would you be using drivers/firmware/pcdp.c as that is ia64 only? That
shouldn't have an impact that I can see.

Can you print the options string in serial8250_console_setup? Maybe it
is getting lost when the real console is setup.

Rob

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Tue, Jun 10, 2014 at 3:52 PM, Tony Luck <tony.luck@gmail.com> wrote:
> On Mon, Jun 9, 2014 at 4:18 PM, Rob Herring <robherring2@gmail.com> wrote:
>> It should do auto detect of the baud-rate if it is not specified which
>> for 8250 is just reading the baud-rate divider and calculating the
>> baud-rate using the uart clock. It should just reprogram the divider
>> with the same divider value. I don't see anything obvious why this
>> would have broken.
>
> Something very weird is happening.  Output is good so long as I put the
> trailing ",115200" on the command line.
>
> But I made early_serial8250_setup() printk() the return value it got
> from probe_baud() - in case is was somehow getting 115201 or some
> other silly value ... nope. Exactly 115200.
>
> I also can't explain why the "noise" comes and goes a dozen
> times during boot,
>
> Does some other place in the kernel look at the "uart..." command
> line argument?

Would you be using drivers/firmware/pcdp.c as that is ia64 only? That
shouldn't have an impact that I can see.

Can you print the options string in serial8250_console_setup? Maybe it
is getting lost when the real console is setup.

Rob

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On Tue, Jun 10, 2014 at 3:52 PM, Tony Luck <tony.luck@gmail.com> wrote:
> On Mon, Jun 9, 2014 at 4:18 PM, Rob Herring <robherring2@gmail.com> wrote:
>> It should do auto detect of the baud-rate if it is not specified which
>> for 8250 is just reading the baud-rate divider and calculating the
>> baud-rate using the uart clock. It should just reprogram the divider
>> with the same divider value. I don't see anything obvious why this
>> would have broken.
>
> Something very weird is happening.  Output is good so long as I put the
> trailing ",115200" on the command line.
>
> But I made early_serial8250_setup() printk() the return value it got
> from probe_baud() - in case is was somehow getting 115201 or some
> other silly value ... nope. Exactly 115200.
>
> I also can't explain why the "noise" comes and goes a dozen
> times during boot,
>
> Does some other place in the kernel look at the "uart..." command
> line argument?

Would you be using drivers/firmware/pcdp.c as that is ia64 only? That
shouldn't have an impact that I can see.

Can you print the options string in serial8250_console_setup? Maybe it
is getting lost when the real console is setup.

Rob

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On 06/10/2014 03:52 PM, Tony Luck wrote:
> On Mon, Jun 9, 2014 at 4:18 PM, Rob Herring <robherring2@gmail.com> wrote:
>> It should do auto detect of the baud-rate if it is not specified which
>> for 8250 is just reading the baud-rate divider and calculating the
>> baud-rate using the uart clock. It should just reprogram the divider
>> with the same divider value. I don't see anything obvious why this
>> would have broken.
> 
> Something very weird is happening.  Output is good so long as I put the
> trailing ",115200" on the command line.
> 
> But I made early_serial8250_setup() printk() the return value it got
> from probe_baud() - in case is was somehow getting 115201 or some
> other silly value ... nope. Exactly 115200.
> 
> I also can't explain why the "noise" comes and goes a dozen
> times during boot,
> 
> Does some other place in the kernel look at the "uart..." command
> line argument?

I think I figured it out. The function 
serial8250_find_port_for_earlycon is failing to match 'uart' console to 
'ttyS' console and transfer the options. It was also failing to create 
an option string when the baud rate is probed. Can you try out the 
below patch?

Rob

8<-------------------------------------------------------------------
diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
index cfef801..4858b8a 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -144,8 +144,11 @@ static int __init early_serial8250_setup(struct earlycon_device *device,
 	if (!(device->port.membase || device->port.iobase))
 		return 0;
 
-	if (!device->baud)
+	if (!device->baud) {
 		device->baud = probe_baud(&device->port);
+		snprintf(device->options, sizeof(device->options), "%u",
+			 device->baud);
+	}
 
 	init_port(device);
 
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index 5131b5e..d20e6d8 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -25,7 +25,7 @@
 #include <asm/serial.h>
 
 static struct console early_con = {
-	.name =		"earlycon",
+	.name =		"uart",
 	.flags =	CON_PRINTBUFFER | CON_BOOT,
 	.index =	-1,
 };

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On 06/10/2014 03:52 PM, Tony Luck wrote:
> On Mon, Jun 9, 2014 at 4:18 PM, Rob Herring <robherring2@gmail.com> wrote:
>> It should do auto detect of the baud-rate if it is not specified which
>> for 8250 is just reading the baud-rate divider and calculating the
>> baud-rate using the uart clock. It should just reprogram the divider
>> with the same divider value. I don't see anything obvious why this
>> would have broken.
> 
> Something very weird is happening.  Output is good so long as I put the
> trailing ",115200" on the command line.
> 
> But I made early_serial8250_setup() printk() the return value it got
> from probe_baud() - in case is was somehow getting 115201 or some
> other silly value ... nope. Exactly 115200.
> 
> I also can't explain why the "noise" comes and goes a dozen
> times during boot,
> 
> Does some other place in the kernel look at the "uart..." command
> line argument?

I think I figured it out. The function 
serial8250_find_port_for_earlycon is failing to match 'uart' console to 
'ttyS' console and transfer the options. It was also failing to create 
an option string when the baud rate is probed. Can you try out the 
below patch?

Rob

8<-------------------------------------------------------------------
diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
index cfef801..4858b8a 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -144,8 +144,11 @@ static int __init early_serial8250_setup(struct earlycon_device *device,
 	if (!(device->port.membase || device->port.iobase))
 		return 0;
 
-	if (!device->baud)
+	if (!device->baud) {
 		device->baud = probe_baud(&device->port);
+		snprintf(device->options, sizeof(device->options), "%u",
+			 device->baud);
+	}
 
 	init_port(device);
 
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index 5131b5e..d20e6d8 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -25,7 +25,7 @@
 #include <asm/serial.h>
 
 static struct console early_con = {
-	.name =		"earlycon",
+	.name =		"uart",
 	.flags =	CON_PRINTBUFFER | CON_BOOT,
 	.index =	-1,
 };

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Rob Herring]

On 06/10/2014 03:52 PM, Tony Luck wrote:
> On Mon, Jun 9, 2014 at 4:18 PM, Rob Herring <robherring2@gmail.com> wrote:
>> It should do auto detect of the baud-rate if it is not specified which
>> for 8250 is just reading the baud-rate divider and calculating the
>> baud-rate using the uart clock. It should just reprogram the divider
>> with the same divider value. I don't see anything obvious why this
>> would have broken.
> 
> Something very weird is happening.  Output is good so long as I put the
> trailing ",115200" on the command line.
> 
> But I made early_serial8250_setup() printk() the return value it got
> from probe_baud() - in case is was somehow getting 115201 or some
> other silly value ... nope. Exactly 115200.
> 
> I also can't explain why the "noise" comes and goes a dozen
> times during boot,
> 
> Does some other place in the kernel look at the "uart..." command
> line argument?

I think I figured it out. The function 
serial8250_find_port_for_earlycon is failing to match 'uart' console to 
'ttyS' console and transfer the options. It was also failing to create 
an option string when the baud rate is probed. Can you try out the 
below patch?

Rob

8<-------------------------------------------------------------------
diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
index cfef801..4858b8a 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -144,8 +144,11 @@ static int __init early_serial8250_setup(struct earlycon_device *device,
 	if (!(device->port.membase || device->port.iobase))
 		return 0;
 
-	if (!device->baud)
+	if (!device->baud) {
 		device->baud = probe_baud(&device->port);
+		snprintf(device->options, sizeof(device->options), "%u",
+			 device->baud);
+	}
 
 	init_port(device);
 
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index 5131b5e..d20e6d8 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -25,7 +25,7 @@
 #include <asm/serial.h>
 
 static struct console early_con = {
-	.name =		"earlycon",
+	.name =		"uart",
 	.flags =	CON_PRINTBUFFER | CON_BOOT,
 	.index =	-1,
 };

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Tony Luck]

On Wed, Jun 11, 2014 at 10:58 AM, Rob Herring <robherring2@gmail.com> wrote:
> I think I figured it out. The function
> serial8250_find_port_for_earlycon is failing to match 'uart' console to
> 'ttyS' console and transfer the options. It was also failing to create
> an option string when the baud rate is probed. Can you try out the
> below patch?

Rob,

That works.  Thanks for digging deeper into this.

Here's a tag for when you push that patch:

Reported-and-tested-by: Tony Luck <tony.luck@intel.com>

-Tony

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Tony Luck]

On Wed, Jun 11, 2014 at 10:58 AM, Rob Herring <robherring2@gmail.com> wrote:
> I think I figured it out. The function
> serial8250_find_port_for_earlycon is failing to match 'uart' console to
> 'ttyS' console and transfer the options. It was also failing to create
> an option string when the baud rate is probed. Can you try out the
> below patch?

Rob,

That works.  Thanks for digging deeper into this.

Here's a tag for when you push that patch:

Reported-and-tested-by: Tony Luck <tony.luck@intel.com>

-Tony

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Tony Luck]

On Wed, Jun 11, 2014 at 10:58 AM, Rob Herring <robherring2@gmail.com> wrote:
> I think I figured it out. The function
> serial8250_find_port_for_earlycon is failing to match 'uart' console to
> 'ttyS' console and transfer the options. It was also failing to create
> an option string when the baud rate is probed. Can you try out the
> below patch?

Rob,

That works.  Thanks for digging deeper into this.

Here's a tag for when you push that patch:

Reported-and-tested-by: Tony Luck <tony.luck@intel.com>

-Tony

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Wed, Jun 11, 2014 at 10:58 AM, Rob Herring <robherring2@gmail.com> wrote:
> On 06/10/2014 03:52 PM, Tony Luck wrote:
> I think I figured it out. The function
> serial8250_find_port_for_earlycon is failing to match 'uart' console to
> 'ttyS' console and transfer the options. It was also failing to create
> an option string when the baud rate is probed. Can you try out the
> below patch?
>
> Rob
>
> 8<-------------------------------------------------------------------
> diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
> index cfef801..4858b8a 100644
> --- a/drivers/tty/serial/8250/8250_early.c
> +++ b/drivers/tty/serial/8250/8250_early.c
> @@ -144,8 +144,11 @@ static int __init early_serial8250_setup(struct earlycon_device *device,
>         if (!(device->port.membase || device->port.iobase))
>                 return 0;
>
> -       if (!device->baud)
> +       if (!device->baud) {
>                 device->baud = probe_baud(&device->port);
> +               snprintf(device->options, sizeof(device->options), "%u",
> +                        device->baud);
> +       }
>
>         init_port(device);
>
> diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
> index 5131b5e..d20e6d8 100644
> --- a/drivers/tty/serial/earlycon.c
> +++ b/drivers/tty/serial/earlycon.c
> @@ -25,7 +25,7 @@
>  #include <asm/serial.h>
>
>  static struct console early_con = {
> -       .name =         "earlycon",
> +       .name =         "uart",
>         .flags =        CON_PRINTBUFFER | CON_BOOT,
>         .index =        -1,
>  };
>

Yes, that is right fix.

For the name in early_con with "uart", please add some comments that
serial8250_find_port_for_earlycon() will look for "uart"...

Thanks

Yinghai

Re: [PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Wed, Jun 11, 2014 at 10:58 AM, Rob Herring <robherring2@gmail.com> wrote:
> On 06/10/2014 03:52 PM, Tony Luck wrote:
> I think I figured it out. The function
> serial8250_find_port_for_earlycon is failing to match 'uart' console to
> 'ttyS' console and transfer the options. It was also failing to create
> an option string when the baud rate is probed. Can you try out the
> below patch?
>
> Rob
>
> 8<-------------------------------------------------------------------
> diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
> index cfef801..4858b8a 100644
> --- a/drivers/tty/serial/8250/8250_early.c
> +++ b/drivers/tty/serial/8250/8250_early.c
> @@ -144,8 +144,11 @@ static int __init early_serial8250_setup(struct earlycon_device *device,
>         if (!(device->port.membase || device->port.iobase))
>                 return 0;
>
> -       if (!device->baud)
> +       if (!device->baud) {
>                 device->baud = probe_baud(&device->port);
> +               snprintf(device->options, sizeof(device->options), "%u",
> +                        device->baud);
> +       }
>
>         init_port(device);
>
> diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
> index 5131b5e..d20e6d8 100644
> --- a/drivers/tty/serial/earlycon.c
> +++ b/drivers/tty/serial/earlycon.c
> @@ -25,7 +25,7 @@
>  #include <asm/serial.h>
>
>  static struct console early_con = {
> -       .name =         "earlycon",
> +       .name =         "uart",
>         .flags =        CON_PRINTBUFFER | CON_BOOT,
>         .index =        -1,
>  };
>

Yes, that is right fix.

For the name in early_con with "uart", please add some comments that
serial8250_find_port_for_earlycon() will look for "uart"...

Thanks

Yinghai

[PATCH v2 3/7] tty/serial: convert 8250 to generic earlycon

[Yinghai Lu]

On Wed, Jun 11, 2014 at 10:58 AM, Rob Herring <robherring2@gmail.com> wrote:
> On 06/10/2014 03:52 PM, Tony Luck wrote:
> I think I figured it out. The function
> serial8250_find_port_for_earlycon is failing to match 'uart' console to
> 'ttyS' console and transfer the options. It was also failing to create
> an option string when the baud rate is probed. Can you try out the
> below patch?
>
> Rob
>
> 8<-------------------------------------------------------------------
> diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
> index cfef801..4858b8a 100644
> --- a/drivers/tty/serial/8250/8250_early.c
> +++ b/drivers/tty/serial/8250/8250_early.c
> @@ -144,8 +144,11 @@ static int __init early_serial8250_setup(struct earlycon_device *device,
>         if (!(device->port.membase || device->port.iobase))
>                 return 0;
>
> -       if (!device->baud)
> +       if (!device->baud) {
>                 device->baud = probe_baud(&device->port);
> +               snprintf(device->options, sizeof(device->options), "%u",
> +                        device->baud);
> +       }
>
>         init_port(device);
>
> diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
> index 5131b5e..d20e6d8 100644
> --- a/drivers/tty/serial/earlycon.c
> +++ b/drivers/tty/serial/earlycon.c
> @@ -25,7 +25,7 @@
>  #include <asm/serial.h>
>
>  static struct console early_con = {
> -       .name =         "earlycon",
> +       .name =         "uart",
>         .flags =        CON_PRINTBUFFER | CON_BOOT,
>         .index =        -1,
>  };
>

Yes, that is right fix.

For the name in early_con with "uart", please add some comments that
serial8250_find_port_for_earlycon() will look for "uart"...

Thanks

Yinghai