[PATCH v2 00/10] ARM: renesas RCar: Add boot-mode-reg core support

[PATCH v2 00/10] ARM: renesas RCar: Add boot-mode-reg core support

[Dirk Behme]

This is a resend of

http://www.spinics.net/lists/linux-sh/msg45969.html

Besides some minor clean up and fixes, it's rebased against

https://git.kernel.org/cgit/linux/kernel/git/geert/renesas-drivers.git/log/?h=topic/gen3-latest
0ea1cc9f0c9537d3fb42722c188
[WIP] arm64: r8a7796: Integration

and adds support for RCar Gen3. Additionally, it moves the MODEMR
register to device tree instead of hard coding its address.

These patches are available in

https://github.com/dirkbehme/linux-renesas-rcar-gen3/commits/geert/topic/gen3-latest-modereg

too.

It's boot tested on r8a7795 Salvator-X and checked that the same
mode value is read without and with this patch series.

Dirk

Changes in v2:

* Correct link & subject in introduction patch 0000
* Fix some spelling errors
* Drop the goto in boot_mode_reg_get() and boot_mode_reg_get()
* Convert device tree node to renesas,rcar-rst and use whole reset device
* Add devcie tree node documentation
* Preserve compatibility with old DTBs that don't have the node in DT

[PATCH v2 01/10] boot-mode-reg: Add core

[Dirk Behme]

From: Simon Horman <horms+renesas@verge.net.au>

The motivation for this new module is to add a small frame work to allow
kernel subsystems to obtain boot mode information from a centralised
source using a new, and hopefully soon well-known, API.

The new API consists of two function calls and nothing more:

boot_mode_reg_set: Should be called by platform-specific drivers
                   to register the boot mode register value which
		   they obtain from hardware or otherwise.

boot_mode_reg_get: Should be called by consumers; subsystems that
                   wish to know he boot mode register.

The boot mode register is a 32bit unsigned entity,
the meaning of its values are implementation dependent.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
---
 MAINTAINERS                         |  1 +
 drivers/misc/Kconfig                |  1 +
 drivers/misc/Makefile               |  1 +
 drivers/misc/boot-mode-reg/Kconfig  | 11 ++++++
 drivers/misc/boot-mode-reg/Makefile |  6 +++
 drivers/misc/boot-mode-reg/core.c   | 76 +++++++++++++++++++++++++++++++++++++
 include/misc/boot-mode-reg.h        | 24 ++++++++++++
 7 files changed, 120 insertions(+)
 create mode 100644 drivers/misc/boot-mode-reg/Kconfig
 create mode 100644 drivers/misc/boot-mode-reg/Makefile
 create mode 100644 drivers/misc/boot-mode-reg/core.c
 create mode 100644 include/misc/boot-mode-reg.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 23e68db..e2bf6ea 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10734,6 +10734,7 @@ S:	Maintained
 F:	Documentation/sh/
 F:	arch/sh/
 F:	drivers/sh/
+F:	drivers/misc/boot-mode-reg/
 
 SUSPEND TO RAM
 M:	"Rafael J. Wysocki" <rjw@rjwysocki.net>
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index a216b46..deba6b6 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -816,4 +816,5 @@ source "drivers/misc/mic/Kconfig"
 source "drivers/misc/genwqe/Kconfig"
 source "drivers/misc/echo/Kconfig"
 source "drivers/misc/cxl/Kconfig"
+source "drivers/misc/boot-mode-reg/Kconfig"
 endmenu
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index b2fb6dbf..d2a8ae4 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -57,3 +57,4 @@ obj-$(CONFIG_ECHO)		+= echo/
 obj-$(CONFIG_VEXPRESS_SYSCFG)	+= vexpress-syscfg.o
 obj-$(CONFIG_CXL_BASE)		+= cxl/
 obj-$(CONFIG_PANEL)             += panel.o
+obj-$(CONFIG_BOOT_MODE_REG_CORE)	+= boot-mode-reg/
diff --git a/drivers/misc/boot-mode-reg/Kconfig b/drivers/misc/boot-mode-reg/Kconfig
new file mode 100644
index 0000000..3c4ddde
--- /dev/null
+++ b/drivers/misc/boot-mode-reg/Kconfig
@@ -0,0 +1,11 @@
+#
+# Boot Mode Register Drivers
+#
+
+config BOOT_MODE_REG_CORE
+	tristate "Boot Mode Register Core Driver"
+	default n
+	depends on ARCH_SHMOBILE || ARCH_RENESAS || COMPILE_TEST
+	help
+	  Say Y here to allow support for drivers to read boot mode
+	  registers and make the value available to other subsystems.
diff --git a/drivers/misc/boot-mode-reg/Makefile b/drivers/misc/boot-mode-reg/Makefile
new file mode 100644
index 0000000..19134b2
--- /dev/null
+++ b/drivers/misc/boot-mode-reg/Makefile
@@ -0,0 +1,6 @@
+
+#
+# Makefile for misc devices that really don't fit anywhere else.
+#
+
+obj-$(CONFIG_BOOT_MODE_REG_CORE)	+= core.o
diff --git a/drivers/misc/boot-mode-reg/core.c b/drivers/misc/boot-mode-reg/core.c
new file mode 100644
index 0000000..983bf4c
--- /dev/null
+++ b/drivers/misc/boot-mode-reg/core.c
@@ -0,0 +1,76 @@
+/*
+ * Boot Mode Register
+ *
+ * Copyright (C) 2015 Simon Horman
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * 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.
+ */
+
+#include <asm/errno.h>
+
+#include <linux/export.h>
+#include <linux/module.h>
+
+#include <misc/boot-mode-reg.h>
+
+static DEFINE_MUTEX(boot_mode_mutex);
+static bool boot_mode_is_set;
+static u32 boot_mode;
+
+/**
+ * boot_mode_reg_get() - retrieve boot mode register value
+ * @mode: implementation-dependent boot mode register value
+ *
+ * Retrieves the boot mode register value previously registered
+ * using boot_mode_reg_set().
+ *
+ * return: 0 on success
+ */
+int boot_mode_reg_get(u32 *mode)
+{
+	int err = -ENOENT;
+
+	mutex_lock(&boot_mode_mutex);
+	if (boot_mode_is_set) {
+		*mode = boot_mode;
+		err = 0;
+	}
+	mutex_unlock(&boot_mode_mutex);
+	return err;
+}
+EXPORT_SYMBOL_GPL(boot_mode_reg_get);
+
+/**
+ * boot_mode_reg_set() - record boot mode register value
+ * @mode: implementation-dependent boot mode register value
+ *
+ * Records the boot mode register value which may subsequently
+ * be retrieved using boot_mode_reg_get().
+ *
+ * return: 0 on success
+ */
+int boot_mode_reg_set(u32 mode)
+{
+	int err = -EBUSY;
+
+	mutex_lock(&boot_mode_mutex);
+	if (!boot_mode_is_set) {
+		boot_mode = mode;
+		boot_mode_is_set = true;
+		err = 0;
+	}
+	mutex_unlock(&boot_mode_mutex);
+	return err;
+}
+EXPORT_SYMBOL_GPL(boot_mode_reg_set);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Simon Horman <horms@verge.net.au>");
+MODULE_DESCRIPTION("Core Boot Mode Register Driver");
diff --git a/include/misc/boot-mode-reg.h b/include/misc/boot-mode-reg.h
new file mode 100644
index 0000000..34ee653
--- /dev/null
+++ b/include/misc/boot-mode-reg.h
@@ -0,0 +1,24 @@
+/*
+ * Boot Mode Register
+ *
+ * Copyright (C) 2015 Simon Horman
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * 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.
+ */
+
+#ifndef _BOOT_MODE_REG_H
+#define _BOOT_MODE_REG_H
+
+#include <linux/types.h>
+
+int boot_mode_reg_get(u32 *mode);
+int boot_mode_reg_set(u32 mode);
+
+#endif
-- 
2.8.0

[PATCH v2 02/10] boot-mode-reg: Add R-Car driver

[Dirk Behme]

From: Simon Horman <horms+renesas@verge.net.au>

Boot mode register driver for R-Car.

If running on a supported platform it reads the boot mode register and
records it using the boot mode register infrastructure established by an
earlier patch.

rcar_init_boot_mode() is exported allow it to be explicitly called in
cases where the boot mode register is needed before init calls are made.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
---
 drivers/misc/boot-mode-reg/Kconfig  |  8 +++++
 drivers/misc/boot-mode-reg/Makefile |  1 +
 drivers/misc/boot-mode-reg/rcar.c   | 60 +++++++++++++++++++++++++++++++++++++
 include/misc/boot-mode-reg.h        |  3 ++
 4 files changed, 72 insertions(+)
 create mode 100644 drivers/misc/boot-mode-reg/rcar.c

diff --git a/drivers/misc/boot-mode-reg/Kconfig b/drivers/misc/boot-mode-reg/Kconfig
index 3c4ddde..3868c36 100644
--- a/drivers/misc/boot-mode-reg/Kconfig
+++ b/drivers/misc/boot-mode-reg/Kconfig
@@ -9,3 +9,11 @@ config BOOT_MODE_REG_CORE
 	help
 	  Say Y here to allow support for drivers to read boot mode
 	  registers and make the value available to other subsystems.
+
+config BOOT_MODE_REG_RCAR
+	tristate "Boot Mode Register Driver for Renesas R-Car SoCs"
+	default n
+	select BOOT_MODE_REG_CORE
+	help
+	  Say Y here to allow support for reading the boot mode register
+	  on Renesas R-Car SoCs.
diff --git a/drivers/misc/boot-mode-reg/Makefile b/drivers/misc/boot-mode-reg/Makefile
index 19134b2..5469a1d 100644
--- a/drivers/misc/boot-mode-reg/Makefile
+++ b/drivers/misc/boot-mode-reg/Makefile
@@ -4,3 +4,4 @@
 #
 
 obj-$(CONFIG_BOOT_MODE_REG_CORE)	+= core.o
+obj-$(CONFIG_BOOT_MODE_REG_RCAR)	+= rcar.o
diff --git a/drivers/misc/boot-mode-reg/rcar.c b/drivers/misc/boot-mode-reg/rcar.c
new file mode 100644
index 0000000..c3b778fe
--- /dev/null
+++ b/drivers/misc/boot-mode-reg/rcar.c
@@ -0,0 +1,60 @@
+/*
+ * R-Car Boot Mode Register Driver
+ *
+ * Copyright (C) 2015 Simon Horman
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * 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.
+ */
+
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+
+#include <misc/boot-mode-reg.h>
+
+#define MODEMR 0xe6160060
+
+static int __init rcar_read_mode_pins(void)
+{
+	void __iomem *modemr;
+	int err = -ENOMEM;
+	static u32 mode;
+
+	modemr = ioremap_nocache(MODEMR, 4);
+	if (!modemr) {
+		pr_err("failed to map boot mode register");
+		goto err;
+	}
+	mode = ioread32(modemr);
+	iounmap(modemr);
+
+	err = boot_mode_reg_set(mode);
+err:
+	if (err)
+		pr_err("failed to initialise boot mode");
+	return err;
+}
+
+int __init rcar_init_boot_mode(void)
+{
+	if (of_machine_is_compatible("renesas,r8a7790") ||
+	    of_machine_is_compatible("renesas,r8a7791") ||
+	    of_machine_is_compatible("renesas,r8a7792") ||
+	    of_machine_is_compatible("renesas,r8a7793") ||
+	    of_machine_is_compatible("renesas,r8a7794"))
+		return rcar_read_mode_pins();
+
+	return 0;
+}
+early_initcall(rcar_init_boot_mode);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Simon Horman <horms@verge.net.au>");
+MODULE_DESCRIPTION("R-Car Boot Mode Register Driver");
diff --git a/include/misc/boot-mode-reg.h b/include/misc/boot-mode-reg.h
index 34ee653..35d7f57 100644
--- a/include/misc/boot-mode-reg.h
+++ b/include/misc/boot-mode-reg.h
@@ -21,4 +21,7 @@
 int boot_mode_reg_get(u32 *mode);
 int boot_mode_reg_set(u32 mode);
 
+/* Allow explicit initialisation before initcalls */
+int rcar_init_boot_mode(void);
+
 #endif
-- 
2.8.0

[PATCH v2 03/10] arm: renesas: rcar-gen2: Obtain MD pin value using boot-mode-reg

[Dirk Behme]

From: Simon Horman <horms+renesas@verge.net.au>

Use new boot mode reg infrastructure to obtain the mode pin
value for initialising arch timer for R-Car Gen2 SoCs.

Subsequent patches will remove other calls to rcar_gen2_read_mode_pins()
and in turn that function.

rcar_init_boot_mode() is called to implicitly initialise
the R-Car Gen2 boot mod register driver as rcar_gen2_timer_init()
is run before initcalls.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
---
 arch/arm/mach-shmobile/Kconfig           |  1 +
 arch/arm/mach-shmobile/setup-rcar-gen2.c | 24 +++++++++++++++++++++---
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-shmobile/Kconfig b/arch/arm/mach-shmobile/Kconfig
index fe4ccb5..314dcaa 100644
--- a/arch/arm/mach-shmobile/Kconfig
+++ b/arch/arm/mach-shmobile/Kconfig
@@ -23,6 +23,7 @@ config ARCH_RCAR_GEN2
 	select RENESAS_IRQC
 	select SYS_SUPPORTS_SH_CMT
 	select PCI_DOMAINS if PCI
+	select BOOT_MODE_REG_RCAR
 
 config ARCH_RMOBILE
 	bool
diff --git a/arch/arm/mach-shmobile/setup-rcar-gen2.c b/arch/arm/mach-shmobile/setup-rcar-gen2.c
index 1c6fd11..a45b05b 100644
--- a/arch/arm/mach-shmobile/setup-rcar-gen2.c
+++ b/arch/arm/mach-shmobile/setup-rcar-gen2.c
@@ -24,6 +24,7 @@
 #include <linux/memblock.h>
 #include <linux/of.h>
 #include <linux/of_fdt.h>
+#include <misc/boot-mode-reg.h>
 #include <asm/mach/arch.h>
 #include "common.h"
 #include "rcar-gen2.h"
@@ -49,13 +50,19 @@ u32 rcar_gen2_read_mode_pins(void)
 #define CNTCR 0
 #define CNTFID0 0x20
 
-void __init rcar_gen2_timer_init(void)
+void __init rcar_gen2_timer_init_for_arch_timer(void)
 {
-	u32 mode = rcar_gen2_read_mode_pins();
 #ifdef CONFIG_ARM_ARCH_TIMER
 	void __iomem *base;
 	int extal_mhz = 0;
-	u32 freq;
+	u32 freq, mode;
+	int err;
+
+	err = boot_mode_reg_get(&mode);
+	if (err) {
+		pr_err("%s: failed obtain boot mode\n", __func__);
+		return;
+	}
 
 	if (of_machine_is_compatible("renesas,r8a7794")) {
 		freq = 260000000 / 8;	/* ZS / 8 */
@@ -126,7 +133,18 @@ void __init rcar_gen2_timer_init(void)
 
 	iounmap(base);
 #endif /* CONFIG_ARM_ARCH_TIMER */
+}
+
+void __init rcar_gen2_timer_init(void)
+{
+	int err;
+	u32 mode = rcar_gen2_read_mode_pins();
+
+	err = rcar_init_boot_mode();
+	if (err)
+		pr_err("Could not initialise boot mode register driver\n");
 
+	rcar_gen2_timer_init_for_arch_timer();
 	rcar_gen2_clocks_init(mode);
 	clocksource_probe();
 }
-- 
2.8.0

[PATCH v2 04/10] arm: renesas: r8a7791: Obtain MD pin value using boot-mode-reg

[Dirk Behme]

From: Simon Horman <horms+renesas@verge.net.au>

Use new boot mode reg infrastructure to obtain the mode pin
value when initialising SMP for r8a7791 SoC.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
---
 arch/arm/mach-shmobile/smp-r8a7791.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/arch/arm/mach-shmobile/smp-r8a7791.c b/arch/arm/mach-shmobile/smp-r8a7791.c
index 2d6417a..00d794d 100644
--- a/arch/arm/mach-shmobile/smp-r8a7791.c
+++ b/arch/arm/mach-shmobile/smp-r8a7791.c
@@ -20,6 +20,8 @@
 
 #include <asm/smp_plat.h>
 
+#include <misc/boot-mode-reg.h>
+
 #include "common.h"
 #include "platsmp-apmu.h"
 #include "r8a7791.h"
@@ -45,8 +47,17 @@ static void __init r8a7791_smp_prepare_cpus(unsigned int max_cpus)
 static int r8a7791_smp_boot_secondary(unsigned int cpu,
 				      struct task_struct *idle)
 {
+	int err;
+	u32 mode;
+
+	err = boot_mode_reg_get(&mode);
+	if (err) {
+		pr_warn("Unable to retrieve boot mode register\n");
+		return err;
+	}
+
 	/* Error out when hardware debug mode is enabled */
-	if (rcar_gen2_read_mode_pins() & BIT(21)) {
+	if (mode & BIT(21)) {
 		pr_warn("Unable to boot CPU%u when MD21 is set\n", cpu);
 		return -ENOTSUPP;
 	}
-- 
2.8.0

[PATCH v2 05/10] clk: renesas: rcar-gen2: Obtain MD pin value using boot-mode-reg

[Dirk Behme]

From: Simon Horman <horms+renesas@verge.net.au>

Use new boot mode reg infrastructure to obtain the mode pin
value for initializing clocks for for R-Car Gen2 SoCs.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
---
 arch/arm/mach-shmobile/setup-rcar-gen2.c |  3 +--
 drivers/clk/renesas/clk-rcar-gen2.c      | 12 ++++++++++--
 include/linux/clk/renesas.h              |  2 +-
 3 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/arch/arm/mach-shmobile/setup-rcar-gen2.c b/arch/arm/mach-shmobile/setup-rcar-gen2.c
index a45b05b..2af84d8 100644
--- a/arch/arm/mach-shmobile/setup-rcar-gen2.c
+++ b/arch/arm/mach-shmobile/setup-rcar-gen2.c
@@ -138,14 +138,13 @@ void __init rcar_gen2_timer_init_for_arch_timer(void)
 void __init rcar_gen2_timer_init(void)
 {
 	int err;
-	u32 mode = rcar_gen2_read_mode_pins();
 
 	err = rcar_init_boot_mode();
 	if (err)
 		pr_err("Could not initialise boot mode register driver\n");
 
 	rcar_gen2_timer_init_for_arch_timer();
-	rcar_gen2_clocks_init(mode);
+	rcar_gen2_clocks_init();
 	clocksource_probe();
 }
 
diff --git a/drivers/clk/renesas/clk-rcar-gen2.c b/drivers/clk/renesas/clk-rcar-gen2.c
index 00e6aba..0109878 100644
--- a/drivers/clk/renesas/clk-rcar-gen2.c
+++ b/drivers/clk/renesas/clk-rcar-gen2.c
@@ -20,6 +20,8 @@
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 
+#include <misc/boot-mode-reg.h>
+
 struct rcar_gen2_cpg {
 	struct clk_onecell_data data;
 	spinlock_t lock;
@@ -421,9 +423,15 @@ static void __init rcar_gen2_cpg_clocks_init(struct device_node *np)
 CLK_OF_DECLARE(rcar_gen2_cpg_clks, "renesas,rcar-gen2-cpg-clocks",
 	       rcar_gen2_cpg_clocks_init);
 
-void __init rcar_gen2_clocks_init(u32 mode)
+void __init rcar_gen2_clocks_init(void)
 {
-	cpg_mode = mode;
+	int err;
+
+	err = boot_mode_reg_get(&cpg_mode);
+	if (err) {
+		pr_err("%s: failed to obtain boot mode\n", __func__);
+		return;
+	}
 
 	of_clk_init(NULL);
 }
diff --git a/include/linux/clk/renesas.h b/include/linux/clk/renesas.h
index ba6fa41..d4a1518 100644
--- a/include/linux/clk/renesas.h
+++ b/include/linux/clk/renesas.h
@@ -22,7 +22,7 @@ struct generic_pm_domain;
 
 void r8a7778_clocks_init(u32 mode);
 void r8a7779_clocks_init(u32 mode);
-void rcar_gen2_clocks_init(u32 mode);
+void rcar_gen2_clocks_init(void);
 
 void cpg_mstp_add_clk_domain(struct device_node *np);
 #ifdef CONFIG_CLK_RENESAS_CPG_MSTP
-- 
2.8.0

[PATCH v2 06/10] arm: renesas: rcar-gen2: Remove unused rcar_gen2_read_mode_pins()

[Dirk Behme]

From: Simon Horman <horms+renesas@verge.net.au>

The new boot mode reg infrastructure is now used in
place of rcar_gen2_read_mode_pins so the latter may now be removed.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
---
 arch/arm/mach-shmobile/rcar-gen2.h       |  1 -
 arch/arm/mach-shmobile/setup-rcar-gen2.c | 18 ------------------
 2 files changed, 19 deletions(-)

diff --git a/arch/arm/mach-shmobile/rcar-gen2.h b/arch/arm/mach-shmobile/rcar-gen2.h
index 8a66b4a..4c4ec37 100644
--- a/arch/arm/mach-shmobile/rcar-gen2.h
+++ b/arch/arm/mach-shmobile/rcar-gen2.h
@@ -3,7 +3,6 @@
 
 void rcar_gen2_timer_init(void);
 #define MD(nr) BIT(nr)
-u32 rcar_gen2_read_mode_pins(void);
 void rcar_gen2_reserve(void);
 void rcar_gen2_pm_init(void);
 
diff --git a/arch/arm/mach-shmobile/setup-rcar-gen2.c b/arch/arm/mach-shmobile/setup-rcar-gen2.c
index 2af84d8..5942b93 100644
--- a/arch/arm/mach-shmobile/setup-rcar-gen2.c
+++ b/arch/arm/mach-shmobile/setup-rcar-gen2.c
@@ -29,24 +29,6 @@
 #include "common.h"
 #include "rcar-gen2.h"
 
-#define MODEMR 0xe6160060
-
-u32 rcar_gen2_read_mode_pins(void)
-{
-	static u32 mode;
-	static bool mode_valid;
-
-	if (!mode_valid) {
-		void __iomem *modemr = ioremap_nocache(MODEMR, 4);
-		BUG_ON(!modemr);
-		mode = ioread32(modemr);
-		iounmap(modemr);
-		mode_valid = true;
-	}
-
-	return mode;
-}
-
 #define CNTCR 0
 #define CNTFID0 0x20
 
-- 
2.8.0

[PATCH v2 07/10] arm: renesas: rcar-gen3: Make boot-mode-reg Gen3 compatible

[Dirk Behme]

From: Dirk Behme <dirk.behme@gmail.com>

The boot mode register is available on Renesas Gen3, too.
Use the same driver on Gen3 as on Gen2.

Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
---
 arch/arm64/Kconfig.platforms      | 1 +
 drivers/misc/boot-mode-reg/rcar.c | 4 +++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/Kconfig.platforms b/arch/arm64/Kconfig.platforms
index fda93a2..591ab8f 100644
--- a/arch/arm64/Kconfig.platforms
+++ b/arch/arm64/Kconfig.platforms
@@ -106,6 +106,7 @@ config ARCH_SHMOBILE
 config ARCH_RENESAS
 	bool "Renesas SoC Platforms"
 	select ARCH_SHMOBILE
+	select BOOT_MODE_REG_RCAR
 	select PINCTRL
 	select PM
 	select PM_GENERIC_DOMAINS
diff --git a/drivers/misc/boot-mode-reg/rcar.c b/drivers/misc/boot-mode-reg/rcar.c
index c3b778fe..e994980 100644
--- a/drivers/misc/boot-mode-reg/rcar.c
+++ b/drivers/misc/boot-mode-reg/rcar.c
@@ -48,7 +48,9 @@ int __init rcar_init_boot_mode(void)
 	    of_machine_is_compatible("renesas,r8a7791") ||
 	    of_machine_is_compatible("renesas,r8a7792") ||
 	    of_machine_is_compatible("renesas,r8a7793") ||
-	    of_machine_is_compatible("renesas,r8a7794"))
+	    of_machine_is_compatible("renesas,r8a7794") ||
+	    of_machine_is_compatible("renesas,r8a7795") ||
+	    of_machine_is_compatible("renesas,r8a7796"))
 		return rcar_read_mode_pins();
 
 	return 0;
-- 
2.8.0

[PATCH v2 08/10] clk: renesas: rcar-gen3: Obtain MD pin value using boot-mode-reg

[Dirk Behme]

From: Dirk Behme <dirk.behme@gmail.com>

Use new boot mode reg infrastructure to obtain the mode pin
value for initialising clocks for for R-Car Gen3 SoCs.

Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
---
 drivers/clk/renesas/r8a7795-cpg-mssr.c | 11 ++++++++++-
 drivers/clk/renesas/r8a7796-cpg-mssr.c | 11 ++++++++++-
 drivers/clk/renesas/rcar-gen3-cpg.c    | 17 -----------------
 drivers/clk/renesas/rcar-gen3-cpg.h    |  1 -
 4 files changed, 20 insertions(+), 20 deletions(-)

diff --git a/drivers/clk/renesas/r8a7795-cpg-mssr.c b/drivers/clk/renesas/r8a7795-cpg-mssr.c
index e53aff5..23bd58f 100644
--- a/drivers/clk/renesas/r8a7795-cpg-mssr.c
+++ b/drivers/clk/renesas/r8a7795-cpg-mssr.c
@@ -18,6 +18,8 @@
 
 #include <dt-bindings/clock/r8a7795-cpg-mssr.h>
 
+#include <misc/boot-mode-reg.h>
+
 #include "renesas-cpg-mssr.h"
 #include "rcar-gen3-cpg.h"
 
@@ -294,7 +296,14 @@ static const struct rcar_gen3_cpg_pll_config cpg_pll_configs[16] __initconst = {
 static int __init r8a7795_cpg_mssr_init(struct device *dev)
 {
 	const struct rcar_gen3_cpg_pll_config *cpg_pll_config;
-	u32 cpg_mode = rcar_gen3_read_mode_pins();
+	u32 cpg_mode;
+	int err;
+
+	err = boot_mode_reg_get(&cpg_mode);
+	if (err) {
+		dev_err(dev, "Failed obtain boot mode: %i\n", err);
+		return err;
+	}
 
 	cpg_pll_config = &cpg_pll_configs[CPG_PLL_CONFIG_INDEX(cpg_mode)];
 	if (!cpg_pll_config->extal_div) {
diff --git a/drivers/clk/renesas/r8a7796-cpg-mssr.c b/drivers/clk/renesas/r8a7796-cpg-mssr.c
index c84b549..2ecb135 100644
--- a/drivers/clk/renesas/r8a7796-cpg-mssr.c
+++ b/drivers/clk/renesas/r8a7796-cpg-mssr.c
@@ -19,6 +19,8 @@
 
 #include <dt-bindings/clock/r8a7796-cpg-mssr.h>
 
+#include <misc/boot-mode-reg.h>
+
 #include "renesas-cpg-mssr.h"
 #include "rcar-gen3-cpg.h"
 
@@ -159,7 +161,14 @@ static const struct rcar_gen3_cpg_pll_config cpg_pll_configs[16] __initconst = {
 static int __init r8a7796_cpg_mssr_init(struct device *dev)
 {
 	const struct rcar_gen3_cpg_pll_config *cpg_pll_config;
-	u32 cpg_mode = rcar_gen3_read_mode_pins();
+	u32 cpg_mode;
+	int err;
+
+	err = boot_mode_reg_get(&cpg_mode);
+	if (err) {
+		dev_err(dev, "Failed obtain boot mode: %i\n", err);
+		return err;
+	}
 
 	cpg_pll_config = &cpg_pll_configs[CPG_PLL_CONFIG_INDEX(cpg_mode)];
 	if (!cpg_pll_config->extal_div) {
diff --git a/drivers/clk/renesas/rcar-gen3-cpg.c b/drivers/clk/renesas/rcar-gen3-cpg.c
index bb4f2f9..9d76076 100644
--- a/drivers/clk/renesas/rcar-gen3-cpg.c
+++ b/drivers/clk/renesas/rcar-gen3-cpg.c
@@ -333,23 +333,6 @@ struct clk * __init rcar_gen3_cpg_clk_register(struct device *dev,
 					 __clk_get_name(parent), 0, mult, div);
 }
 
-/*
- * Reset register definitions.
- */
-#define MODEMR	0xe6160060
-
-u32 __init rcar_gen3_read_mode_pins(void)
-{
-	void __iomem *modemr = ioremap_nocache(MODEMR, 4);
-	u32 mode;
-
-	BUG_ON(!modemr);
-	mode = ioread32(modemr);
-	iounmap(modemr);
-
-	return mode;
-}
-
 int __init rcar_gen3_cpg_init(const struct rcar_gen3_cpg_pll_config *config,
 			      unsigned int clk_extalr)
 {
diff --git a/drivers/clk/renesas/rcar-gen3-cpg.h b/drivers/clk/renesas/rcar-gen3-cpg.h
index f699085..f788f48 100644
--- a/drivers/clk/renesas/rcar-gen3-cpg.h
+++ b/drivers/clk/renesas/rcar-gen3-cpg.h
@@ -33,7 +33,6 @@ struct rcar_gen3_cpg_pll_config {
 
 #define CPG_RCKCR	0x240
 
-u32 rcar_gen3_read_mode_pins(void);
 struct clk *rcar_gen3_cpg_clk_register(struct device *dev,
 	const struct cpg_core_clk *core, const struct cpg_mssr_info *info,
 	struct clk **clks, void __iomem *base);
-- 
2.8.0

[PATCH v2 09/10] ARM: dts: r8a779x: Add reset module support

[Dirk Behme]

From: Dirk Behme <dirk.behme@gmail.com>

The reset module on RCar Gen2 and Gen3 SoCs contains various reset handling
related registers. Their content is implementation dependent.

Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
---
 .../devicetree/bindings/misc/renesas,rcar-rst.txt         | 15 +++++++++++++++
 arch/arm/boot/dts/r8a7790.dtsi                            |  5 +++++
 arch/arm/boot/dts/r8a7791.dtsi                            |  5 +++++
 arch/arm/boot/dts/r8a7793.dtsi                            |  5 +++++
 arch/arm/boot/dts/r8a7794.dtsi                            |  6 ++++++
 arch/arm64/boot/dts/renesas/r8a7795.dtsi                  |  5 +++++
 arch/arm64/boot/dts/renesas/r8a7796.dtsi                  |  5 +++++
 7 files changed, 46 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/misc/renesas,rcar-rst.txt

diff --git a/Documentation/devicetree/bindings/misc/renesas,rcar-rst.txt b/Documentation/devicetree/bindings/misc/renesas,rcar-rst.txt
new file mode 100644
index 0000000..88695c4
--- /dev/null
+++ b/Documentation/devicetree/bindings/misc/renesas,rcar-rst.txt
@@ -0,0 +1,15 @@
+Renesas RCar r8a779x reset module
+-----------------------------------------------------
+This binding defines the reset module found on Renesas RCar r8a779x
+SoCs. The reset module contains several reset related registers,
+the meaning of them is implementation dependent.
+
+Required properties:
+- compatible : "renesas,rcar-rst"
+- reg : Location and size of the reset module
+
+Example:
+	reset-controller@e6160000 {
+		compatible = "renesas,rcar-rst";
+		reg = <0 0xe6160000 0 0x200>;
+	};
\ No newline at end of file
diff --git a/arch/arm/boot/dts/r8a7790.dtsi b/arch/arm/boot/dts/r8a7790.dtsi
index 83cf23c..d9b86c4 100644
--- a/arch/arm/boot/dts/r8a7790.dtsi
+++ b/arch/arm/boot/dts/r8a7790.dtsi
@@ -1102,6 +1102,11 @@
 			#power-domain-cells = <0>;
 		};
 
+		reset-controller@e6160000 {
+			compatible = "renesas,rcar-rst";
+			reg = <0 0xe6160000 0 0x200>;
+		};
+
 		/* Variable factor clocks */
 		sd2_clk: sd2@e6150078 {
 			compatible = "renesas,r8a7790-div6-clock", "renesas,cpg-div6-clock";
diff --git a/arch/arm/boot/dts/r8a7791.dtsi b/arch/arm/boot/dts/r8a7791.dtsi
index db67e34..9c7a210 100644
--- a/arch/arm/boot/dts/r8a7791.dtsi
+++ b/arch/arm/boot/dts/r8a7791.dtsi
@@ -1122,6 +1122,11 @@
 			#power-domain-cells = <0>;
 		};
 
+		reset-controller@e6160000 {
+			compatible = "renesas,rcar-rst";
+			reg = <0 0xe6160000 0 0x200>;
+		};
+
 		/* Variable factor clocks */
 		sd2_clk: sd2@e6150078 {
 			compatible = "renesas,r8a7791-div6-clock", "renesas,cpg-div6-clock";
diff --git a/arch/arm/boot/dts/r8a7793.dtsi b/arch/arm/boot/dts/r8a7793.dtsi
index 1dd6d20..31858c6 100644
--- a/arch/arm/boot/dts/r8a7793.dtsi
+++ b/arch/arm/boot/dts/r8a7793.dtsi
@@ -933,6 +933,11 @@
 			#power-domain-cells = <0>;
 		};
 
+		reset-controller@e6160000 {
+			compatible = "renesas,rcar-rst";
+			reg = <0 0xe6160000 0 0x200>;
+		};
+
 		/* Variable factor clocks */
 		sd2_clk: sd2@e6150078 {
 			compatible = "renesas,r8a7793-div6-clock",
diff --git a/arch/arm/boot/dts/r8a7794.dtsi b/arch/arm/boot/dts/r8a7794.dtsi
index f334a3a..c419ca6 100644
--- a/arch/arm/boot/dts/r8a7794.dtsi
+++ b/arch/arm/boot/dts/r8a7794.dtsi
@@ -932,6 +932,12 @@
 					     "rcan";
 			#power-domain-cells = <0>;
 		};
+
+		reset-controller@e6160000 {
+			compatible = "renesas,rcar-rst";
+			reg = <0 0xe6160000 0 0x200>;
+		};
+
 		/* Variable factor clocks */
 		sd2_clk: sd2@e6150078 {
 			compatible = "renesas,r8a7794-div6-clock", "renesas,cpg-div6-clock";
diff --git a/arch/arm64/boot/dts/renesas/r8a7795.dtsi b/arch/arm64/boot/dts/renesas/r8a7795.dtsi
index 7181db0..1266975 100644
--- a/arch/arm64/boot/dts/renesas/r8a7795.dtsi
+++ b/arch/arm64/boot/dts/renesas/r8a7795.dtsi
@@ -309,6 +309,11 @@
 			#power-domain-cells = <0>;
 		};
 
+		reset-controller@e6160000 {
+			compatible = "renesas,rcar-rst";
+			reg = <0 0xe6160000 0 0x200>;
+		};
+
 		sysc: system-controller@e6180000 {
 			compatible = "renesas,r8a7795-sysc";
 			reg = <0 0xe6180000 0 0x0400>;
diff --git a/arch/arm64/boot/dts/renesas/r8a7796.dtsi b/arch/arm64/boot/dts/renesas/r8a7796.dtsi
index 1389528..c3d6075 100644
--- a/arch/arm64/boot/dts/renesas/r8a7796.dtsi
+++ b/arch/arm64/boot/dts/renesas/r8a7796.dtsi
@@ -109,6 +109,11 @@
 			#power-domain-cells = <0>;
 		};
 
+		reset-controller@e6160000 {
+			compatible = "renesas,rcar-rst";
+			reg = <0 0xe6160000 0 0x200>;
+		};
+
 		sysc: system-controller@e6180000 {
 			compatible = "renesas,r8a7796-sysc";
 			reg = <0 0xe6180000 0 0x0400>;
-- 
2.8.0

[PATCH v2 10/10] boot-mode-reg: Convert to device tree

[Dirk Behme]

From: Dirk Behme <dirk.behme@gmail.com>

Instead of using a hard coded address in the driver for the boot mode
register, optain it from the device tree.

Signed-off-by: Dirk Behme <dirk.behme@gmail.com>
---
 drivers/misc/boot-mode-reg/rcar.c | 27 ++++++++++++++++++++-------
 1 file changed, 20 insertions(+), 7 deletions(-)

diff --git a/drivers/misc/boot-mode-reg/rcar.c b/drivers/misc/boot-mode-reg/rcar.c
index e994980..0b23352 100644
--- a/drivers/misc/boot-mode-reg/rcar.c
+++ b/drivers/misc/boot-mode-reg/rcar.c
@@ -16,24 +16,37 @@
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_address.h>
 
 #include <misc/boot-mode-reg.h>
 
-#define MODEMR 0xe6160060
+#define RCAR_RST_BASE 0xe6160000
+#define RCAR_RST_SIZE 0x200
+#define MODEMR 0x60
 
 static int __init rcar_read_mode_pins(void)
 {
-	void __iomem *modemr;
+	void __iomem *reset;
+	struct device_node *np;
 	int err = -ENOMEM;
 	static u32 mode;
 
-	modemr = ioremap_nocache(MODEMR, 4);
-	if (!modemr) {
-		pr_err("failed to map boot mode register");
+	np = of_find_compatible_node(NULL, NULL, "renesas,rcar-rst");
+	if (np)
+		reset = of_iomap(np, 0);
+	else {
+		pr_warn("can't find renesas rcar-rst device node");
+		reset = ioremap_nocache(RCAR_RST_BASE, RCAR_RST_SIZE);
+	}
+
+	if (!reset) {
+		pr_err("failed to map reset registers");
+		of_node_put(np);
 		goto err;
 	}
-	mode = ioread32(modemr);
-	iounmap(modemr);
+	mode = ioread32(reset + MODEMR);
+	iounmap(reset);
+	of_node_put(np);
 
 	err = boot_mode_reg_set(mode);
 err:
-- 
2.8.0

Re: [PATCH v2 01/10] boot-mode-reg: Add core

[Geert Uytterhoeven]

Hi Dirk,

On Wed, May 11, 2016 at 7:29 AM, Dirk Behme <dirk.behme@de.bosch.com> wrote:
> --- /dev/null
> +++ b/drivers/misc/boot-mode-reg/core.c

> +/**
> + * boot_mode_reg_set() - record boot mode register value
> + * @mode: implementation-dependent boot mode register value
> + *
> + * Records the boot mode register value which may subsequently
> + * be retrieved using boot_mode_reg_get().
> + *
> + * return: 0 on success
> + */
> +int boot_mode_reg_set(u32 mode)
> +{
> +       int err = -EBUSY;
> +
> +       mutex_lock(&boot_mode_mutex);
> +       if (!boot_mode_is_set) {

You've dropped the check for calling this function a subsequent time with
a different value of mode?

> +               boot_mode = mode;
> +               boot_mode_is_set = true;
> +               err = 0;
> +       }
> +       mutex_unlock(&boot_mode_mutex);
> +       return err;
> +}

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v2 09/10] ARM: dts: r8a779x: Add reset module support

[Geert Uytterhoeven]

Hi Dirk,

On Wed, May 11, 2016 at 7:29 AM, Dirk Behme <dirk.behme@de.bosch.com> wrote:
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/misc/renesas,rcar-rst.txt
> @@ -0,0 +1,15 @@
> +Renesas RCar r8a779x reset module
> +-----------------------------------------------------
> +This binding defines the reset module found on Renesas RCar r8a779x
> +SoCs. The reset module contains several reset related registers,
> +the meaning of them is implementation dependent.
> +
> +Required properties:
> +- compatible : "renesas,rcar-rst"
> +- reg : Location and size of the reset module
> +
> +Example:
> +       reset-controller@e6160000 {
> +               compatible = "renesas,rcar-rst";
> +               reg = <0 0xe6160000 0 0x200>;
> +       };

While I understand you want to match on a single comptible value, the RST
module itself highly depends on the actual SoC.
Furthermore, R-Car Gen1 doesn't have RST.

Hence I'd go for requiring 2 compatible values:
  - An SoC-specific one, e.g. "renesas,r8a7795-rst",
  - A family-specific one, e.g. "renesas,rcar-gen3-rst".

Your driver code can match against the two family-specific compatible values
using of_find_matching_node().

> \ No newline at end of file

Oops.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v2 01/10] boot-mode-reg: Add core

[Dirk Behme]

Hi Geert,

On 11.05.2016 09:54, Geert Uytterhoeven wrote:
> Hi Dirk,
>
> On Wed, May 11, 2016 at 7:29 AM, Dirk Behme <dirk.behme@de.bosch.com> wrote:
>> --- /dev/null
>> +++ b/drivers/misc/boot-mode-reg/core.c
>
>> +/**
>> + * boot_mode_reg_set() - record boot mode register value
>> + * @mode: implementation-dependent boot mode register value
>> + *
>> + * Records the boot mode register value which may subsequently
>> + * be retrieved using boot_mode_reg_get().
>> + *
>> + * return: 0 on success
>> + */
>> +int boot_mode_reg_set(u32 mode)
>> +{
>> +       int err = -EBUSY;
>> +
>> +       mutex_lock(&boot_mode_mutex);
>> +       if (!boot_mode_is_set) {
>
> You've dropped the check for calling this function a subsequent time with
> a different value of mode?


Sometimes inverting 'complex' if statements is not that easy ;)

You mean

if (!boot_mode_is_set || boot_mode != mode)

?

Best regards

Dirk

Re: [PATCH v2 01/10] boot-mode-reg: Add core

[Geert Uytterhoeven]

Hi Dirk,

On Wed, May 11, 2016 at 10:39 AM, Dirk Behme <dirk.behme@de.bosch.com> wrote:
> On 11.05.2016 09:54, Geert Uytterhoeven wrote:
>> On Wed, May 11, 2016 at 7:29 AM, Dirk Behme <dirk.behme@de.bosch.com>
>> wrote:
>>>
>>> --- /dev/null
>>> +++ b/drivers/misc/boot-mode-reg/core.c
>>
>>> +/**
>>> + * boot_mode_reg_set() - record boot mode register value
>>> + * @mode: implementation-dependent boot mode register value
>>> + *
>>> + * Records the boot mode register value which may subsequently
>>> + * be retrieved using boot_mode_reg_get().
>>> + *
>>> + * return: 0 on success
>>> + */
>>> +int boot_mode_reg_set(u32 mode)
>>> +{
>>> +       int err = -EBUSY;
>>> +
>>> +       mutex_lock(&boot_mode_mutex);
>>> +       if (!boot_mode_is_set) {
>>
>> You've dropped the check for calling this function a subsequent time with
>> a different value of mode?
>
> Sometimes inverting 'complex' if statements is not that easy ;)
>
> You mean
>
> if (!boot_mode_is_set || boot_mode != mode)

No, De Morgan says

        if (!boot_mode_is_set || boot_mode == mode)

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v2 01/10] boot-mode-reg: Add core

[Dirk Behme]

Hi Geert,

On 11.05.2016 10:41, Geert Uytterhoeven wrote:
> Hi Dirk,
>
> On Wed, May 11, 2016 at 10:39 AM, Dirk Behme <dirk.behme@de.bosch.com> wrote:
>> On 11.05.2016 09:54, Geert Uytterhoeven wrote:
>>> On Wed, May 11, 2016 at 7:29 AM, Dirk Behme <dirk.behme@de.bosch.com>
>>> wrote:
>>>>
>>>> --- /dev/null
>>>> +++ b/drivers/misc/boot-mode-reg/core.c
>>>
>>>> +/**
>>>> + * boot_mode_reg_set() - record boot mode register value
>>>> + * @mode: implementation-dependent boot mode register value
>>>> + *
>>>> + * Records the boot mode register value which may subsequently
>>>> + * be retrieved using boot_mode_reg_get().
>>>> + *
>>>> + * return: 0 on success
>>>> + */
>>>> +int boot_mode_reg_set(u32 mode)
>>>> +{
>>>> +       int err = -EBUSY;
>>>> +
>>>> +       mutex_lock(&boot_mode_mutex);
>>>> +       if (!boot_mode_is_set) {
>>>
>>> You've dropped the check for calling this function a subsequent time with
>>> a different value of mode?
>>
>> Sometimes inverting 'complex' if statements is not that easy ;)
>>
>> You mean
>>
>> if (!boot_mode_is_set || boot_mode != mode)
>
> No, De Morgan says
>
>         if (!boot_mode_is_set || boot_mode == mode)


Hmm, sorry if I don't have enough coffee today ;)

But why should we do

if (... boot_mode == mode)
	boot_mode = mode;

?

Or in other words:

We want to execute the if code if

boot_mode_is_set is false

or

boot_mode is not equal mode, i.e. mode has changed

?


Best regards

Dirk

Re: [PATCH v2 01/10] boot-mode-reg: Add core

[Geert Uytterhoeven]

Hi Dirk,

On Wed, May 11, 2016 at 10:55 AM, Dirk Behme <dirk.behme@de.bosch.com> wrote:
> On 11.05.2016 10:41, Geert Uytterhoeven wrote:
>> On Wed, May 11, 2016 at 10:39 AM, Dirk Behme <dirk.behme@de.bosch.com>
>> wrote:
>>> On 11.05.2016 09:54, Geert Uytterhoeven wrote:
>>>> On Wed, May 11, 2016 at 7:29 AM, Dirk Behme <dirk.behme@de.bosch.com>
>>>> wrote:
>>>>> --- /dev/null
>>>>> +++ b/drivers/misc/boot-mode-reg/core.c
>>>>> +/**
>>>>> + * boot_mode_reg_set() - record boot mode register value
>>>>> + * @mode: implementation-dependent boot mode register value
>>>>> + *
>>>>> + * Records the boot mode register value which may subsequently
>>>>> + * be retrieved using boot_mode_reg_get().
>>>>> + *
>>>>> + * return: 0 on success
>>>>> + */
>>>>> +int boot_mode_reg_set(u32 mode)
>>>>> +{
>>>>> +       int err = -EBUSY;
>>>>> +
>>>>> +       mutex_lock(&boot_mode_mutex);
>>>>> +       if (!boot_mode_is_set) {
>>>>
>>>> You've dropped the check for calling this function a subsequent time
>>>> with
>>>> a different value of mode?
>>>
>>> Sometimes inverting 'complex' if statements is not that easy ;)
>>>
>>> You mean
>>>
>>> if (!boot_mode_is_set || boot_mode != mode)
>>
>>
>> No, De Morgan says
>>
>>         if (!boot_mode_is_set || boot_mode == mode)
>
> Hmm, sorry if I don't have enough coffee today ;)
>
> But why should we do
>
> if (... boot_mode == mode)
>         boot_mode = mode;
>
> ?
>
> Or in other words:
>
> We want to execute the if code if
>
> boot_mode_is_set is false
>
> or
>
> boot_mode is not equal mode, i.e. mode has changed
>
> ?

We want to fail if the mode has changed.
Doing the assignment a second time doesn't hurt.

But as this seems to hurt readability, the better solution may be:

        if (!boot_mode_is_set) {
                boot_mode = mode;
                boot_mode_is_set = true;
                err = 0;
        } else if (boot_mode == mode) {
               err = 0;
        } else {
               err = -EBUSY;
        }

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v2 09/10] ARM: dts: r8a779x: Add reset module support

[Dirk Behme]

Hi Geert,

On 11.05.2016 10:06, Geert Uytterhoeven wrote:
> Hi Dirk,
>
> On Wed, May 11, 2016 at 7:29 AM, Dirk Behme <dirk.behme@de.bosch.com> wrote:
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/misc/renesas,rcar-rst.txt
>> @@ -0,0 +1,15 @@
>> +Renesas RCar r8a779x reset module
>> +-----------------------------------------------------
>> +This binding defines the reset module found on Renesas RCar r8a779x
>> +SoCs. The reset module contains several reset related registers,
>> +the meaning of them is implementation dependent.
>> +
>> +Required properties:
>> +- compatible : "renesas,rcar-rst"
>> +- reg : Location and size of the reset module
>> +
>> +Example:
>> +       reset-controller@e6160000 {
>> +               compatible = "renesas,rcar-rst";
>> +               reg = <0 0xe6160000 0 0x200>;
>> +       };
>
> While I understand you want to match on a single comptible value, the RST
> module itself highly depends on the actual SoC.
> Furthermore, R-Car Gen1 doesn't have RST.
>
> Hence I'd go for requiring 2 compatible values:
>   - An SoC-specific one, e.g. "renesas,r8a7795-rst",
>   - A family-specific one, e.g. "renesas,rcar-gen3-rst".
>
> Your driver code can match against the two family-specific compatible values
> using of_find_matching_node().


This way? See below [1].

Best regards

Dirk

[1]

--- a/drivers/misc/boot-mode-reg/rcar.c
+++ b/drivers/misc/boot-mode-reg/rcar.c
@@ -16,24 +16,43 @@
  #include <linux/io.h>
  #include <linux/module.h>
  #include <linux/of.h>
+#include <linux/of_address.h>

  #include <misc/boot-mode-reg.h>

-#define MODEMR 0xe6160060
+#define RCAR_RST_BASE 0xe6160000
+#define RCAR_RST_SIZE 0x200
+#define MODEMR 0x60
+
+static struct of_device_id rcar_rst_ids[] __initdata = {
+	{ .compatible = "renesas,rcar-gen2-rst" },
+	{ .compatible = "renesas,rcar-gen3-rst" },
+	{}
+};

  static int __init rcar_read_mode_pins(void)
  {
-	void __iomem *modemr;
+	void __iomem *reset;
+	struct device_node *np;
  	int err = -ENOMEM;
  	static u32 mode;

-	modemr = ioremap_nocache(MODEMR, 4);
-	if (!modemr) {
-		pr_err("failed to map boot mode register");
+	np = of_find_matching_node(NULL, rcar_rst_ids);
+	if (np)
+		reset = of_iomap(np, 0);
+	else {
+		pr_warn("can't find renesas rcar-rst device node");
+		reset = ioremap_nocache(RCAR_RST_BASE, RCAR_RST_SIZE);
+	}
+
+	if (!reset) {
+		pr_err("failed to map reset registers");
+		of_node_put(np);
  		goto err;
  	}
-	mode = ioread32(modemr);
-	iounmap(modemr);
+	mode = ioread32(reset + MODEMR);
+	iounmap(reset);
+	of_node_put(np);

  	err = boot_mode_reg_set(mode);
  err:
--- /dev/null
+++ b/Documentation/devicetree/bindings/misc/renesas,rcar-rst.txt
@@ -0,0 +1,24 @@
+Renesas RCar r8a779x reset module
+-----------------------------------------------------
+This binding defines the reset module found on Renesas RCar r8a779x
+SoCs. The reset module contains several reset related registers,
+the meaning of them is implementation dependent.
+
+Required properties:
+- compatible : "renesas,rcar-gen2-rst" for RCar Gen2 or
+               "renesas,rcar-gen3-rst" for RCar Gen3
+	       and additionally a SoC specific property like
+	       "renesas,r8a7790-rst" or
+	       "renesas,r8a7791-rst" or
+	       "renesas,r8a7792-rst" or
+	       "renesas,r8a7793-rst" or
+	       "renesas,r8a7794-rst" or
+	       "renesas,r8a7795-rst" or
+	       "renesas,r8a7796-rst"
+- reg : Location and size of the reset module
+
+Example:
+	reset-controller@e6160000 {
+		compatible = "renesas,rcar-gen3-rst", "renesas,r8a7795-rst";
+		reg = <0 0xe6160000 0 0x200>;
+	};
diff --git a/arch/arm/boot/dts/r8a7790.dtsi b/arch/arm/boot/dts/r8a7790.dtsi
index 83cf23c..7102002 100644
--- a/arch/arm/boot/dts/r8a7790.dtsi
+++ b/arch/arm/boot/dts/r8a7790.dtsi
@@ -1102,6 +1102,11 @@
  			#power-domain-cells = <0>;
  		};

+		reset-controller@e6160000 {
+			compatible = "renesas,rcar-gen2-rst", "renesas,r8a7790-rst";
+			reg = <0 0xe6160000 0 0x200>;
+		};
+
  		/* Variable factor clocks */
  		sd2_clk: sd2@e6150078 {
  			compatible = "renesas,r8a7790-div6-clock", "renesas,cpg-div6-clock";
diff --git a/arch/arm/boot/dts/r8a7791.dtsi b/arch/arm/boot/dts/r8a7791.dtsi
index db67e34..d54b58e 100644
--- a/arch/arm/boot/dts/r8a7791.dtsi
+++ b/arch/arm/boot/dts/r8a7791.dtsi
@@ -1122,6 +1122,11 @@
  			#power-domain-cells = <0>;
  		};

+		reset-controller@e6160000 {
+			compatible = "renesas,rcar-gen2-rst", "renesas,r8a7791-rst";
+			reg = <0 0xe6160000 0 0x200>;
+		};
+
  		/* Variable factor clocks */
  		sd2_clk: sd2@e6150078 {
  			compatible = "renesas,r8a7791-div6-clock", "renesas,cpg-div6-clock";
diff --git a/arch/arm/boot/dts/r8a7793.dtsi b/arch/arm/boot/dts/r8a7793.dtsi
index 1dd6d20..9ebe978 100644
--- a/arch/arm/boot/dts/r8a7793.dtsi
+++ b/arch/arm/boot/dts/r8a7793.dtsi
@@ -933,6 +933,11 @@
  			#power-domain-cells = <0>;
  		};

+		reset-controller@e6160000 {
+			compatible = "renesas,rcar-gen2-rst", "renesas,r8a7793-rst";
+			reg = <0 0xe6160000 0 0x200>;
+		};
+
  		/* Variable factor clocks */
  		sd2_clk: sd2@e6150078 {
  			compatible = "renesas,r8a7793-div6-clock",
diff --git a/arch/arm/boot/dts/r8a7794.dtsi b/arch/arm/boot/dts/r8a7794.dtsi
index f334a3a..bd998fd 100644
--- a/arch/arm/boot/dts/r8a7794.dtsi
+++ b/arch/arm/boot/dts/r8a7794.dtsi
@@ -932,6 +932,12 @@
  					     "rcan";
  			#power-domain-cells = <0>;
  		};
+
+		reset-controller@e6160000 {
+			compatible = "renesas,rcar-gen2-rst", "renesas,r8a7794-rst";
+			reg = <0 0xe6160000 0 0x200>;
+		};
+
  		/* Variable factor clocks */
  		sd2_clk: sd2@e6150078 {
  			compatible = "renesas,r8a7794-div6-clock", "renesas,cpg-div6-clock";
diff --git a/arch/arm64/boot/dts/renesas/r8a7795.dtsi 
b/arch/arm64/boot/dts/renesas/r8a7795.dtsi
index 7181db0..b846bca 100644
--- a/arch/arm64/boot/dts/renesas/r8a7795.dtsi
+++ b/arch/arm64/boot/dts/renesas/r8a7795.dtsi
@@ -309,6 +309,11 @@
  			#power-domain-cells = <0>;
  		};

+		reset-controller@e6160000 {
+			compatible = "renesas,rcar-gen3-rst", "renesas,r8a7795-rst";
+			reg = <0 0xe6160000 0 0x200>;
+		};
+
  		sysc: system-controller@e6180000 {
  			compatible = "renesas,r8a7795-sysc";
  			reg = <0 0xe6180000 0 0x0400>;
diff --git a/arch/arm64/boot/dts/renesas/r8a7796.dtsi 
b/arch/arm64/boot/dts/renesas/r8a7796.dtsi
index 1389528..7c65f8a 100644
--- a/arch/arm64/boot/dts/renesas/r8a7796.dtsi
+++ b/arch/arm64/boot/dts/renesas/r8a7796.dtsi
@@ -109,6 +109,11 @@
  			#power-domain-cells = <0>;
  		};

+		reset-controller@e6160000 {
+			compatible = "renesas,rcar-gen3-rst", "renesas,r8a7796-rst";
+			reg = <0 0xe6160000 0 0x200>;
+		};
+
  		sysc: system-controller@e6180000 {
  			compatible = "renesas,r8a7796-sysc";
  			reg = <0 0xe6180000 0 0x0400>;

Re: [PATCH v2 09/10] ARM: dts: r8a779x: Add reset module support

[Geert Uytterhoeven]

Hi Dirk,

On Wed, May 11, 2016 at 1:56 PM, Dirk Behme <dirk.behme@de.bosch.com> wrote:
> On 11.05.2016 10:06, Geert Uytterhoeven wrote:
>> On Wed, May 11, 2016 at 7:29 AM, Dirk Behme <dirk.behme@de.bosch.com>
>> wrote:
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/misc/renesas,rcar-rst.txt
>>> @@ -0,0 +1,15 @@
>>> +Renesas RCar r8a779x reset module
>>> +-----------------------------------------------------
>>> +This binding defines the reset module found on Renesas RCar r8a779x
>>> +SoCs. The reset module contains several reset related registers,
>>> +the meaning of them is implementation dependent.
>>> +
>>> +Required properties:
>>> +- compatible : "renesas,rcar-rst"
>>> +- reg : Location and size of the reset module
>>> +
>>> +Example:
>>> +       reset-controller@e6160000 {
>>> +               compatible = "renesas,rcar-rst";
>>> +               reg = <0 0xe6160000 0 0x200>;
>>> +       };
>>
>>
>> While I understand you want to match on a single comptible value, the RST
>> module itself highly depends on the actual SoC.
>> Furthermore, R-Car Gen1 doesn't have RST.
>>
>> Hence I'd go for requiring 2 compatible values:
>>   - An SoC-specific one, e.g. "renesas,r8a7795-rst",
>>   - A family-specific one, e.g. "renesas,rcar-gen3-rst".
>>
>> Your driver code can match against the two family-specific compatible
>> values
>> using of_find_matching_node().
>
> This way? See below [1].
>
> Best regards
>
> Dirk
>
> [1]
>
> --- a/drivers/misc/boot-mode-reg/rcar.c
> +++ b/drivers/misc/boot-mode-reg/rcar.c
> @@ -16,24 +16,43 @@
>  #include <linux/io.h>
>  #include <linux/module.h>
>  #include <linux/of.h>
> +#include <linux/of_address.h>
>
>  #include <misc/boot-mode-reg.h>
>
> -#define MODEMR 0xe6160060
> +#define RCAR_RST_BASE 0xe6160000
> +#define RCAR_RST_SIZE 0x200
> +#define MODEMR 0x60
> +
> +static struct of_device_id rcar_rst_ids[] __initdata = {

const

> +       { .compatible = "renesas,rcar-gen2-rst" },
> +       { .compatible = "renesas,rcar-gen3-rst" },
> +       {}
> +};
>
>  static int __init rcar_read_mode_pins(void)
>  {
> -       void __iomem *modemr;
> +       void __iomem *reset;
> +       struct device_node *np;
>         int err = -ENOMEM;
>         static u32 mode;
>
> -       modemr = ioremap_nocache(MODEMR, 4);
> -       if (!modemr) {
> -               pr_err("failed to map boot mode register");
> +       np = of_find_matching_node(NULL, rcar_rst_ids);

Yep, like this.

> --- /dev/null
> +++ b/Documentation/devicetree/bindings/misc/renesas,rcar-rst.txt
> @@ -0,0 +1,24 @@
> +Renesas RCar r8a779x reset module

R-Car Gen2 and Gen3

> +-----------------------------------------------------
> +This binding defines the reset module found on Renesas RCar r8a779x

R-Car Gen2 and Gen3

> +SoCs. The reset module contains several reset related registers,
> +the meaning of them is implementation dependent.

You may want to add more functionality from
http://www.spinics.net/lists/linux-sh/msg44754.html

> +Required properties:
> +- compatible : "renesas,rcar-gen2-rst" for RCar Gen2 or

R-Car

> +               "renesas,rcar-gen3-rst" for RCar Gen3

R-Car

> +              and additionally a SoC specific property like
> +              "renesas,r8a7790-rst" or
> +              "renesas,r8a7791-rst" or
> +              "renesas,r8a7792-rst" or
> +              "renesas,r8a7793-rst" or
> +              "renesas,r8a7794-rst" or
> +              "renesas,r8a7795-rst" or
> +              "renesas,r8a7796-rst"

The SoC-specific compatible values should be listed first.

> +- reg : Location and size of the reset module
> +
> +Example:
> +       reset-controller@e6160000 {
> +               compatible = "renesas,rcar-gen3-rst", "renesas,r8a7795-rst";

The SoC-specific compatible value should be listed first.
The same is true for the actual dtsi files.

> +               reg = <0 0xe6160000 0 0x200>;
> +       };

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v2 09/10] ARM: dts: r8a779x: Add reset module support

[Dirk Behme]

Hi Geert,

On 11.05.2016 14:13, Geert Uytterhoeven wrote:
> Hi Dirk,
>
> On Wed, May 11, 2016 at 1:56 PM, Dirk Behme <dirk.behme@de.bosch.com> wrote:
>> On 11.05.2016 10:06, Geert Uytterhoeven wrote:
>>> On Wed, May 11, 2016 at 7:29 AM, Dirk Behme <dirk.behme@de.bosch.com>
>>> wrote:
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/misc/renesas,rcar-rst.txt
>>>> @@ -0,0 +1,15 @@
>>>> +Renesas RCar r8a779x reset module
>>>> +-----------------------------------------------------
>>>> +This binding defines the reset module found on Renesas RCar r8a779x
>>>> +SoCs. The reset module contains several reset related registers,
>>>> +the meaning of them is implementation dependent.
>>>> +
>>>> +Required properties:
>>>> +- compatible : "renesas,rcar-rst"
>>>> +- reg : Location and size of the reset module
>>>> +
>>>> +Example:
>>>> +       reset-controller@e6160000 {
>>>> +               compatible = "renesas,rcar-rst";
>>>> +               reg = <0 0xe6160000 0 0x200>;
>>>> +       };
>>>
>>>
>>> While I understand you want to match on a single comptible value, the RST
>>> module itself highly depends on the actual SoC.
>>> Furthermore, R-Car Gen1 doesn't have RST.
>>>
>>> Hence I'd go for requiring 2 compatible values:
>>>   - An SoC-specific one, e.g. "renesas,r8a7795-rst",
>>>   - A family-specific one, e.g. "renesas,rcar-gen3-rst".
>>>
>>> Your driver code can match against the two family-specific compatible
>>> values
>>> using of_find_matching_node().
>>
>> This way? See below [1].
>>
>> Best regards
>>
>> Dirk
>>
>> [1]
>>
>> --- a/drivers/misc/boot-mode-reg/rcar.c
>> +++ b/drivers/misc/boot-mode-reg/rcar.c
>> @@ -16,24 +16,43 @@
>>  #include <linux/io.h>
>>  #include <linux/module.h>
>>  #include <linux/of.h>
>> +#include <linux/of_address.h>
>>
>>  #include <misc/boot-mode-reg.h>
>>
>> -#define MODEMR 0xe6160060
>> +#define RCAR_RST_BASE 0xe6160000
>> +#define RCAR_RST_SIZE 0x200
>> +#define MODEMR 0x60
>> +
>> +static struct of_device_id rcar_rst_ids[] __initdata = {
>
> const
>
>> +       { .compatible = "renesas,rcar-gen2-rst" },
>> +       { .compatible = "renesas,rcar-gen3-rst" },
>> +       {}
>> +};
>>
>>  static int __init rcar_read_mode_pins(void)
>>  {
>> -       void __iomem *modemr;
>> +       void __iomem *reset;
>> +       struct device_node *np;
>>         int err = -ENOMEM;
>>         static u32 mode;
>>
>> -       modemr = ioremap_nocache(MODEMR, 4);
>> -       if (!modemr) {
>> -               pr_err("failed to map boot mode register");
>> +       np = of_find_matching_node(NULL, rcar_rst_ids);
>
> Yep, like this.
>
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/misc/renesas,rcar-rst.txt
>> @@ -0,0 +1,24 @@
>> +Renesas RCar r8a779x reset module
>
> R-Car Gen2 and Gen3
>
>> +-----------------------------------------------------
>> +This binding defines the reset module found on Renesas RCar r8a779x
>
> R-Car Gen2 and Gen3
>
>> +SoCs. The reset module contains several reset related registers,
>> +the meaning of them is implementation dependent.
>
> You may want to add more functionality from
> http://www.spinics.net/lists/linux-sh/msg44754.html


Just an understanding question:

Why do you prefer the solution with the drivers/misc/boot-mode-reg/ 
solution done in this patch series over the solution you proposed in

http://www.spinics.net/lists/linux-sh/msg44755.html

and the reset of that series?

Best regards

Dirk


>> +Required properties:
>> +- compatible : "renesas,rcar-gen2-rst" for RCar Gen2 or
>
> R-Car
>
>> +               "renesas,rcar-gen3-rst" for RCar Gen3
>
> R-Car
>
>> +              and additionally a SoC specific property like
>> +              "renesas,r8a7790-rst" or
>> +              "renesas,r8a7791-rst" or
>> +              "renesas,r8a7792-rst" or
>> +              "renesas,r8a7793-rst" or
>> +              "renesas,r8a7794-rst" or
>> +              "renesas,r8a7795-rst" or
>> +              "renesas,r8a7796-rst"
>
> The SoC-specific compatible values should be listed first.
>
>> +- reg : Location and size of the reset module
>> +
>> +Example:
>> +       reset-controller@e6160000 {
>> +               compatible = "renesas,rcar-gen3-rst", "renesas,r8a7795-rst";
>
> The SoC-specific compatible value should be listed first.
> The same is true for the actual dtsi files.
>
>> +               reg = <0 0xe6160000 0 0x200>;
>> +       };
>

Re: [PATCH v2 09/10] ARM: dts: r8a779x: Add reset module support

[Geert Uytterhoeven]

Hi Dirk,

CC Laurent

On Wed, May 11, 2016 at 3:36 PM, Dirk Behme <dirk.behme@de.bosch.com> wrote:
> Just an understanding question:
>
> Why do you prefer the solution with the drivers/misc/boot-mode-reg/ solution
> done in this patch series over the solution you proposed in
>
> http://www.spinics.net/lists/linux-sh/msg44755.html
>
> and the reset of that series?

Do I? :-)

drivers/misc/boot-mode-reg/ will need agreement outside the linux-renesas-soc
community. My renesas,modemr proposal won't.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v2 09/10] ARM: dts: r8a779x: Add reset module support

[Dirk Behme]

On 11.05.2016 15:51, Geert Uytterhoeven wrote:
> Hi Dirk,
>
> CC Laurent
>
> On Wed, May 11, 2016 at 3:36 PM, Dirk Behme <dirk.behme@de.bosch.com> wrote:
>> Just an understanding question:
>>
>> Why do you prefer the solution with the drivers/misc/boot-mode-reg/ solution
>> done in this patch series over the solution you proposed in
>>
>> http://www.spinics.net/lists/linux-sh/msg44755.html
>>
>> and the reset of that series?
>
> Do I? :-)
>
> drivers/misc/boot-mode-reg/ will need agreement outside the linux-renesas-soc
> community. My renesas,modemr proposal won't.


Then I'll have a look at

http://www.spinics.net/lists/linux-sh/msg44757.html

and drop the boot-mode-reg patches?

Ok?

Do you remember the status of

http://www.spinics.net/lists/linux-sh/msg44755.html

Anything I should know looking at it?

Best regards

Dirk