[U-Boot] [PATCH 00/20] x86: Add CPU uclass and multi-core support for Minnowboard MAX

[U-Boot] [PATCH 00/20] x86: Add CPU uclass and multi-core support for Minnowboard MAX

[Simon Glass]

This series adds a new CPU uclass which is intended to be useful on any
architecture. So far it has a very simple interface and a command to show
CPU details.

This series also introduces multi-core init for x86. It is implemented and
enabled on Minnowboard MAX, a single/dual-core Atom board. A CPU driver is
implemented for generic x86 and Baytrail. The Simple Firmware Interface is
used to provide these details to the kernel, since ACPI is not yet available.

With these changes Minnowboard MAX can boot into Linux with both cores
enabled.

This series is available at u-boot-x86 branch 'cpu-working'.


Simon Glass (20):
  Fix comment nits in board_f.c
  dm: core: Add a function to bind a driver for a device tree node
  x86: Remove unwanted MMC debugging
  x86: Disable -Werror
  Move display_options functions to their own header
  Add print_freq() to display frequencies nicely
  x86: Add support for the Simple Firmware Interface (SFI)
  dm: Implement a CPU uclass
  Add a 'cpu' command to print CPU information
  x86: Add atomic operations
  x86: Add defines for fixed MTRRs
  x86: Add an mfence macro
  x86: Store the GDT pointer in global_data
  x86: Provide access to the IDT
  x86: Add multi-processor init
  x86: Add functions to set and clear bits on MSRs
  x86: Allow CPUs to be set up after relocation
  x86: Add a CPU driver for baytrail
  x86: Tidy up the LAPIC init code
  x86: Enable multi-core init for Minnowboard MAX

 arch/x86/Kconfig                         |  53 ++++
 arch/x86/cpu/Makefile                    |   2 +
 arch/x86/cpu/baytrail/Makefile           |   1 +
 arch/x86/cpu/baytrail/cpu.c              | 206 +++++++++++++
 arch/x86/cpu/baytrail/valleyview.c       |   1 -
 arch/x86/cpu/config.mk                   |   2 +-
 arch/x86/cpu/cpu.c                       |  38 +++
 arch/x86/cpu/interrupts.c                |   5 +
 arch/x86/cpu/ivybridge/model_206ax.c     |   4 +-
 arch/x86/cpu/lapic.c                     |  20 +-
 arch/x86/cpu/mp_init.c                   | 507 +++++++++++++++++++++++++++++++
 arch/x86/cpu/sipi.S                      | 217 +++++++++++++
 arch/x86/dts/minnowmax.dts               |  20 ++
 arch/x86/include/asm/arch-baytrail/msr.h |  30 ++
 arch/x86/include/asm/atomic.h            | 115 +++++++
 arch/x86/include/asm/cpu.h               |  19 ++
 arch/x86/include/asm/global_data.h       |   1 +
 arch/x86/include/asm/interrupt.h         |   2 +
 arch/x86/include/asm/lapic.h             |   7 -
 arch/x86/include/asm/mp.h                |  94 ++++++
 arch/x86/include/asm/msr.h               |  19 ++
 arch/x86/include/asm/mtrr.h              |  14 +
 arch/x86/include/asm/sipi.h              |  79 +++++
 arch/x86/include/asm/smm.h               |  14 +
 arch/x86/include/asm/u-boot-x86.h        |   2 +
 arch/x86/lib/Makefile                    |   1 +
 arch/x86/lib/sfi.c                       | 171 +++++++++++
 arch/x86/lib/zimage.c                    |   7 +
 common/Kconfig                           |   8 +
 common/Makefile                          |   1 +
 common/board_f.c                         |   9 +-
 common/board_r.c                         |   2 +-
 common/cmd_cpu.c                         | 113 +++++++
 configs/minnowmax_defconfig              |   4 +
 drivers/Kconfig                          |   2 +
 drivers/Makefile                         |   1 +
 drivers/core/lists.c                     |   9 +-
 drivers/cpu/Kconfig                      |   8 +
 drivers/cpu/Makefile                     |   7 +
 drivers/cpu/cpu-uclass.c                 |  61 ++++
 include/common.h                         |  16 +-
 include/cpu.h                            |  84 +++++
 include/display_options.h                |  59 ++++
 include/dm/lists.h                       |  16 +
 include/dm/uclass-id.h                   |   1 +
 include/linux/sfi.h                      | 139 +++++++++
 lib/display_options.c                    |  54 +++-
 47 files changed, 2191 insertions(+), 54 deletions(-)
 create mode 100644 arch/x86/cpu/baytrail/cpu.c
 create mode 100644 arch/x86/cpu/mp_init.c
 create mode 100644 arch/x86/cpu/sipi.S
 create mode 100644 arch/x86/include/asm/arch-baytrail/msr.h
 create mode 100644 arch/x86/include/asm/atomic.h
 create mode 100644 arch/x86/include/asm/mp.h
 create mode 100644 arch/x86/include/asm/sipi.h
 create mode 100644 arch/x86/include/asm/smm.h
 create mode 100644 arch/x86/lib/sfi.c
 create mode 100644 common/cmd_cpu.c
 create mode 100644 drivers/cpu/Kconfig
 create mode 100644 drivers/cpu/Makefile
 create mode 100644 drivers/cpu/cpu-uclass.c
 create mode 100644 include/cpu.h
 create mode 100644 include/display_options.h
 create mode 100644 include/linux/sfi.h

-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 01/20] Fix comment nits in board_f.c

[Simon Glass]

Try to make it a little clearer.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 common/board_f.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/common/board_f.c b/common/board_f.c
index 322e070..fbbad1b 100644
--- a/common/board_f.c
+++ b/common/board_f.c
@@ -73,7 +73,7 @@ DECLARE_GLOBAL_DATA_PTR;
 #endif
 
 /*
- * sjg: IMO this code should be
+ * TODO(sjg at chromium.org): IMO this code should be
  * refactored to a single function, something like:
  *
  * void led_set_state(enum led_colour_t colour, int on);
@@ -300,7 +300,7 @@ __weak ulong board_get_usable_ram_top(ulong total_size)
 {
 #ifdef CONFIG_SYS_SDRAM_BASE
 	/*
-	 * Detect whether we have so much RAM it goes past the end of our
+	 * Detect whether we have so much RAM that it goes past the end of our
 	 * 32-bit address space. If so, clip the usable RAM so it doesn't.
 	 */
 	if (gd->ram_top < CONFIG_SYS_SDRAM_BASE)
@@ -507,7 +507,7 @@ static int reserve_global_data(void)
 static int reserve_fdt(void)
 {
 	/*
-	 * If the device tree is sitting immediate above our image then we
+	 * If the device tree is sitting immediately above our image then we
 	 * must relocate it. If it is embedded in the data section, then it
 	 * will be relocated with other data.
 	 */
@@ -535,7 +535,7 @@ static int reserve_stacks(void)
 	gd->start_addr_sp &= ~0xf;
 
 	/*
-	 * let the architecture specific code tailor gd->start_addr_sp and
+	 * let the architecture-specific code tailor gd->start_addr_sp and
 	 * gd->irq_sp
 	 */
 	return arch_reserve_stacks();
@@ -556,7 +556,6 @@ static int setup_board_part1(void)
 	/*
 	 * Save local variables to board info struct
 	 */
-
 	bd->bi_memstart = CONFIG_SYS_SDRAM_BASE;	/* start of memory */
 	bd->bi_memsize = gd->ram_size;			/* size in bytes */
 
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 02/20] dm: core: Add a function to bind a driver for a device tree node

[Simon Glass]

Some device tree nodes do not have compatible strings but do require
drivers. This is pretty rare, and somewhat unfortunate. Add a function
to permit creation of a driver for any device tree node.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 drivers/core/lists.c |  9 ++++++++-
 include/dm/lists.h   | 16 ++++++++++++++++
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/drivers/core/lists.c b/drivers/core/lists.c
index 647e390..0c49d99 100644
--- a/drivers/core/lists.c
+++ b/drivers/core/lists.c
@@ -74,6 +74,13 @@ int lists_bind_drivers(struct udevice *parent, bool pre_reloc_only)
 int device_bind_driver(struct udevice *parent, const char *drv_name,
 		       const char *dev_name, struct udevice **devp)
 {
+	return device_bind_driver_to_node(parent, drv_name, dev_name, -1, devp);
+}
+
+int device_bind_driver_to_node(struct udevice *parent, const char *drv_name,
+			       const char *dev_name, int node,
+			       struct udevice **devp)
+{
 	struct driver *drv;
 	int ret;
 
@@ -82,7 +89,7 @@ int device_bind_driver(struct udevice *parent, const char *drv_name,
 		printf("Cannot find driver '%s'\n", drv_name);
 		return -ENOENT;
 	}
-	ret = device_bind(parent, drv, dev_name, NULL, -1, devp);
+	ret = device_bind(parent, drv, dev_name, NULL, node, devp);
 	if (ret) {
 		printf("Cannot create device named '%s' (err=%d)\n",
 		       dev_name, ret);
diff --git a/include/dm/lists.h b/include/dm/lists.h
index 1b50af9..61610e6 100644
--- a/include/dm/lists.h
+++ b/include/dm/lists.h
@@ -73,4 +73,20 @@ int lists_bind_fdt(struct udevice *parent, const void *blob, int offset,
 int device_bind_driver(struct udevice *parent, const char *drv_name,
 		       const char *dev_name, struct udevice **devp);
 
+/**
+ * device_bind_driver_to_node() - bind a device to a driver for a node
+ *
+ * This binds a new device to a driver for a given device tree node. This
+ * should only be needed if the node lacks a compatible strings.
+ *
+ * @parent:	Parent device
+ * @drv_name:	Name of driver to attach to this parent
+ * @dev_name:	Name of the new device thus created
+ * @node:	Device tree node
+ * @devp:	Returns the newly bound device
+ */
+int device_bind_driver_to_node(struct udevice *parent, const char *drv_name,
+			       const char *dev_name, int node,
+			       struct udevice **devp);
+
 #endif
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 03/20] x86: Remove unwanted MMC debugging

[Simon Glass]

This printf() should not have made it into the code.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 arch/x86/cpu/baytrail/valleyview.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/x86/cpu/baytrail/valleyview.c b/arch/x86/cpu/baytrail/valleyview.c
index a3e837d..9915da5 100644
--- a/arch/x86/cpu/baytrail/valleyview.c
+++ b/arch/x86/cpu/baytrail/valleyview.c
@@ -16,7 +16,6 @@ static struct pci_device_id mmc_supported[] = {
 
 int cpu_mmc_init(bd_t *bis)
 {
-	printf("mmc init\n");
 	return pci_mmc_init("ValleyView SDHCI", mmc_supported,
 			    ARRAY_SIZE(mmc_supported));
 }
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 04/20] x86: Disable -Werror

[Simon Glass]

This is annoying during development and serves no useful purpose since
warnings are clearly displayed now that we are using Kbuild. Remove this
option.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 arch/x86/cpu/config.mk | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/cpu/config.mk b/arch/x86/cpu/config.mk
index 84aeaf3..4c4d0c7 100644
--- a/arch/x86/cpu/config.mk
+++ b/arch/x86/cpu/config.mk
@@ -7,7 +7,7 @@
 
 CROSS_COMPILE ?= i386-linux-
 
-PLATFORM_CPPFLAGS += -D__I386__ -Werror
+PLATFORM_CPPFLAGS += -D__I386__
 
 # DO NOT MODIFY THE FOLLOWING UNLESS YOU REALLY KNOW WHAT YOU ARE DOING!
 LDPPFLAGS += -DRESET_SEG_START=0xffff0000
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 05/20] Move display_options functions to their own header

[Simon Glass]

Before adding one more function, create a separate header to help reduce
the size of common.h. Add the missing function comments and tidy up.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 include/common.h          | 16 +---------------
 include/display_options.h | 48 +++++++++++++++++++++++++++++++++++++++++++++++
 lib/display_options.c     | 13 -------------
 3 files changed, 49 insertions(+), 28 deletions(-)
 create mode 100644 include/display_options.h

diff --git a/include/common.h b/include/common.h
index cde3474..d4d704a 100644
--- a/include/common.h
+++ b/include/common.h
@@ -192,22 +192,8 @@ int	cpu_init(void);
 
 /* */
 phys_size_t initdram (int);
-int	display_options (void);
 
-/**
- * print_size() - Print a size with a suffic
- *
- * print sizes as "xxx KiB", "xxx.y KiB", "xxx MiB", "xxx.y MiB",
- * xxx GiB, xxx.y GiB, etc as needed; allow for optional trailing string
- * (like "\n")
- *
- * @size:	Size to print
- * @suffix	String to print after the size
- */
-void print_size(uint64_t size, const char *suffix);
-
-int print_buffer(ulong addr, const void *data, uint width, uint count,
-		 uint linelen);
+#include <display_options.h>
 
 /* common/main.c */
 void	main_loop	(void);
diff --git a/include/display_options.h b/include/display_options.h
new file mode 100644
index 0000000..c222ea2
--- /dev/null
+++ b/include/display_options.h
@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ *
+ * (C) Copyright 2000-2002
+ * Wolfgang Denk, DENX Software Engineering, wd at denx.de.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __display_options_h
+#define __display_options_h
+
+/**
+ * print_size() - Print a size with a suffix
+ *
+ * print sizes as "xxx KiB", "xxx.y KiB", "xxx MiB", "xxx.y MiB",
+ * xxx GiB, xxx.y GiB, etc as needed; allow for optional trailing string
+ * (like "\n")
+ *
+ * @size:	Size to print
+ * @suffix	String to print after the size
+ */
+void print_size(uint64_t size, const char *suffix);
+
+/**
+ * print_buffer() - Print data buffer in hex and ascii form
+ *
+ * Data reads are buffered so that each memory address is only read once.
+ * This is useful when displaying the contents of volatile registers.
+ *
+ * @addr:	Starting address to display at start of line
+ * @data:	pointer to data buffer
+ * @width:	data value width.  May be 1, 2, or 4.
+ * @count:	number of values to display
+ * @linelen:	Number of values to print per line; specify 0 for default length
+ */
+int print_buffer(ulong addr, const void *data, uint width, uint count,
+		 uint linelen);
+
+/**
+ * display_options() - display the version string / build tag
+ *
+ * This displays the U-Boot version string. If a build tag is available this
+ * is displayed also.
+ */
+int display_options(void);
+
+#endif
diff --git a/lib/display_options.c b/lib/display_options.c
index d5d17b2..3f32bcd 100644
--- a/lib/display_options.c
+++ b/lib/display_options.c
@@ -63,19 +63,6 @@ void print_size(uint64_t size, const char *s)
 	printf (" %ciB%s", c, s);
 }
 
-/*
- * Print data buffer in hex and ascii form to the terminal.
- *
- * data reads are buffered so that each memory address is only read once.
- * Useful when displaying the contents of volatile registers.
- *
- * parameters:
- *    addr: Starting address to display at start of line
- *    data: pointer to data buffer
- *    width: data value width.  May be 1, 2, or 4.
- *    count: number of values to display
- *    linelen: Number of values to print per line; specify 0 for default length
- */
 #define MAX_LINE_LENGTH_BYTES (64)
 #define DEFAULT_LINE_LENGTH_BYTES (16)
 int print_buffer(ulong addr, const void *data, uint width, uint count,
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 06/20] Add print_freq() to display frequencies nicely

[Simon Glass]

Add a function similar to print_size() that works for frequencies. It can
handle from Hz to GHz.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 include/display_options.h | 11 +++++++++++
 lib/display_options.c     | 41 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 52 insertions(+)

diff --git a/include/display_options.h b/include/display_options.h
index c222ea2..10b4641 100644
--- a/include/display_options.h
+++ b/include/display_options.h
@@ -23,6 +23,17 @@
 void print_size(uint64_t size, const char *suffix);
 
 /**
+ * print_freq() - Print a frequency with a suffix
+ *
+ * print frequencies as "x.xx GHz", "xxx KHz", etc as needed; allow for
+ * optional trailing string (like "\n")
+ *
+ * @freq:	Frequency to print in Hz
+ * @suffix	String to print after the frequency
+ */
+void print_freq(uint64_t freq, const char *suffix);
+
+/**
  * print_buffer() - Print data buffer in hex and ascii form
  *
  * Data reads are buffered so that each memory address is only read once.
diff --git a/lib/display_options.c b/lib/display_options.c
index 3f32bcd..cf6f50b 100644
--- a/lib/display_options.c
+++ b/lib/display_options.c
@@ -7,6 +7,7 @@
 
 #include <config.h>
 #include <common.h>
+#include <div64.h>
 #include <inttypes.h>
 #include <version.h>
 #include <linux/ctype.h>
@@ -22,6 +23,46 @@ int display_options (void)
 	return 0;
 }
 
+#ifndef CONFIG_SH
+/* SH gcc 4.6 toolchain produces "undefined reference to '__umoddi3' here */
+void print_freq(uint64_t freq, const char *s)
+{
+	unsigned long m = 0, n;
+	uint32_t f;
+	static const char names[] = {'G', 'M', 'K'};
+	unsigned long d = 1e9;
+	char c = 0;
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(names); i++, d /= 10) {
+		if (freq >= d) {
+			c = names[i];
+			break;
+		}
+	}
+
+	if (!c) {
+		printf("%" PRIu64 " Hz%s", freq, s);
+		return;
+	}
+
+	f = do_div(freq, d);
+	n = freq;
+
+	/* If there's a remainder, show the first few digits */
+	if (f) {
+		m = f % 1000;
+		while (!(m % 10))
+			m /= 10;
+	}
+
+	printf("%lu", n);
+	if (m)
+		printf(".%ld", m);
+	printf(" %cHz%s", c, s);
+}
+#endif
+
 void print_size(uint64_t size, const char *s)
 {
 	unsigned long m = 0, n;
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 07/20] x86: Add support for the Simple Firmware Interface (SFI)

[Simon Glass]

This provides a way of passing information to Linux without requiring the
full ACPI horror. Provide a rudimentary implementation sufficient to be
recognised and parsed by Linux.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 arch/x86/Kconfig      |  28 +++++++++
 arch/x86/lib/Makefile |   1 +
 arch/x86/lib/sfi.c    | 171 ++++++++++++++++++++++++++++++++++++++++++++++++++
 arch/x86/lib/zimage.c |   7 +++
 include/linux/sfi.h   | 139 ++++++++++++++++++++++++++++++++++++++++
 5 files changed, 346 insertions(+)
 create mode 100644 arch/x86/lib/sfi.c
 create mode 100644 include/linux/sfi.h

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index aaceaef..30a08ec 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -499,6 +499,34 @@ config PCIE_ECAM_BASE
 	  assigned to PCI devices - i.e. the memory and prefetch regions, as
 	  passed to pci_set_region().
 
+config SFI
+	bool "SFI (Simple Firmware Interface) Support"
+	---help---
+	The Simple Firmware Interface (SFI) provides a lightweight method
+	for platform firmware to pass information to the operating system
+	via static tables in memory.  Kernel SFI support is required to
+	boot on SFI-only platforms.  If you have ACPI tables then these are
+	used instead.
+
+	For more information, see http://simplefirmware.org
+
+	Say 'Y' here to enable the kernel to boot properly on SFI-only
+	platforms.
+
+config SFI_BASE
+	hex "SFI base address (0xe0000 to 0xff000)"
+	default 0xe0000
+	depends on SFI
+	help
+	  The OS searches addresses in the range 0xe00000 to 0xffff0 for the
+	  Simple Firmware Interface (SFI) header. Use this option to determine
+	  where the table will be placed. It must be a multiple of 16 bytes and
+	  the header part (which U-Boot places at the end) must not cross a 4KB
+	  boundary. A 4KB-aligned address is recommended for these reasons.
+
+	  U-Boot writes this table in sfi_write_tables() just before booting
+	  the OS.
+
 config BOOTSTAGE
 	default y
 
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index 0178fe1..c55b9be 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -26,6 +26,7 @@ obj-y	+= pirq_routing.o
 obj-y	+= relocate.o
 obj-y += physmem.o
 obj-$(CONFIG_X86_RAMTEST) += ramtest.o
+obj-$(CONFIG_SFI) += sfi.o
 obj-y	+= string.o
 obj-y	+= tables.o
 obj-$(CONFIG_SYS_X86_TSC_TIMER)	+= tsc_timer.o
diff --git a/arch/x86/lib/sfi.c b/arch/x86/lib/sfi.c
new file mode 100644
index 0000000..060651b
--- /dev/null
+++ b/arch/x86/lib/sfi.c
@@ -0,0 +1,171 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+/*
+ * Intel Simple Firmware Interface (SFI)
+ *
+ * Yet another way to pass information to the Linux kernel.
+ *
+ * See https://simplefirmware.org/ for details
+ */
+
+#include <common.h>
+#include <cpu.h>
+#include <dm.h>
+#include <asm/cpu.h>
+#include <asm/ioapic.h>
+#include <dm/uclass-internal.h>
+#include <linux/sfi.h>
+
+struct table_info {
+	u32 base;
+	int ptr;
+	u32 entry_start;
+	u64 table[16];
+	int count;
+};
+
+void *get_entry_start(struct table_info *tab)
+{
+	if (tab->count == ARRAY_SIZE(tab->table))
+		return NULL;
+	tab->entry_start = tab->base + tab->ptr;
+	tab->table[tab->count] = tab->entry_start;
+	tab->entry_start += sizeof(struct sfi_table_header);
+
+	return (void *)tab->entry_start;
+}
+
+static void finish_table(struct table_info *tab, const char *sig, void *entry)
+{
+	struct sfi_table_header *hdr;
+	uint8_t *p;
+	int sum;
+
+	hdr = (struct sfi_table_header *)(tab->base + tab->ptr);
+	strcpy(hdr->sig, sig);
+	hdr->len = sizeof(*hdr) + ((ulong)entry - tab->entry_start);
+	hdr->rev = 1;
+	strncpy(hdr->oem_id, "U-Boot", SFI_OEM_ID_SIZE);
+	strncpy(hdr->oem_table_id, "Table v1", SFI_OEM_TABLE_ID_SIZE);
+	hdr->csum = 0;
+	for (sum = 0, p = (uint8_t *)hdr; (void *)p < entry; p++)
+		sum += *p;
+	hdr->csum = 256 - (sum & 255);
+	tab->ptr += hdr->len;
+	tab->ptr = ALIGN(tab->ptr, 16);
+	tab->count++;
+}
+
+static int sfi_write_system_header(struct table_info *tab)
+{
+	u64 *entry = get_entry_start(tab);
+	int i;
+
+	if (!entry)
+		return -ENOSPC;
+	for (i = 0; i < tab->count; i++)
+		*entry++ = tab->table[i];
+	finish_table(tab, SFI_SIG_SYST, entry);
+
+	return 0;
+}
+
+static int sfi_write_cpus(struct table_info *tab)
+{
+	struct sfi_cpu_table_entry *entry = get_entry_start(tab);
+	struct udevice *dev;
+	int count = 0;
+
+	if (!entry)
+		return -ENOSPC;
+	for (uclass_find_first_device(UCLASS_CPU, &dev);
+	     dev;
+	     uclass_find_next_device(&dev)) {
+		struct cpu_platdata *plat = dev_get_parent_platdata(dev);
+
+		if (!device_active(dev))
+			continue;
+		entry->apic_id = plat->cpu_id;
+		entry++;
+		count++;
+	}
+
+	/* Omit the table if there is only one CPU */
+	if (count > 1)
+		finish_table(tab, SFI_SIG_CPUS, entry);
+
+	return 0;
+}
+
+static int sfi_write_apic(struct table_info *tab)
+{
+	struct sfi_apic_table_entry *entry = get_entry_start(tab);
+
+	if (!entry)
+		return -ENOSPC;
+
+	entry->phys_addr = IO_APIC_ADDR;
+	entry++;
+	finish_table(tab, SFI_SIG_APIC, entry);
+
+	return 0;
+}
+
+static int sfi_write_rtc(struct table_info *tab)
+{
+	struct sfi_rtc_table_entry *entry = get_entry_start(tab);
+
+	if (!entry)
+		return -ENOSPC;
+
+	entry->phys_addr = CONFIG_SYS_ISA_IO_BASE_ADDRESS + 0x70;
+	entry->irq = 0;		/* Should be 8? */
+	entry++;
+	finish_table(tab, SFI_SIG_MRTC, entry);
+
+	return 0;
+}
+
+static int sfi_write_xsdt(struct table_info *tab)
+{
+	struct sfi_xsdt_header *entry = get_entry_start(tab);
+
+	if (!entry)
+		return -ENOSPC;
+
+	entry->oem_revision = 1;
+	entry->creator_id = 1;
+	entry->creator_revision = 1;
+	entry++;
+	finish_table(tab, SFI_SIG_XSDT, entry);
+
+	return 0;
+}
+
+int sfi_write_tables(void)
+{
+	struct table_info table;
+
+	table.base = CONFIG_SFI_BASE;
+	table.ptr = 0;
+	table.count = 0;
+	sfi_write_cpus(&table);
+	sfi_write_apic(&table);
+	sfi_write_rtc(&table);
+
+	/*
+	 * The SFI specification marks the XSDT table as option, but Linux 4.0
+	 * crashes on start-up when it is not provided.
+	 */
+	sfi_write_xsdt(&table);
+
+	/* Finally, write out the system header which points to the others */
+	sfi_write_system_header(&table);
+
+	return 0;
+}
diff --git a/arch/x86/lib/zimage.c b/arch/x86/lib/zimage.c
index c3f8a73..d2c68f6 100644
--- a/arch/x86/lib/zimage.c
+++ b/arch/x86/lib/zimage.c
@@ -24,6 +24,7 @@
 #include <asm/arch/timestamp.h>
 #endif
 #include <linux/compiler.h>
+#include <linux/sfi.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -232,9 +233,15 @@ int setup_zimage(struct boot_params *setup_base, char *cmd_line, int auto_boot,
 {
 	struct setup_header *hdr = &setup_base->hdr;
 	int bootproto = get_boot_protocol(hdr);
+	int ret;
 
 	setup_base->e820_entries = install_e820_map(
 		ARRAY_SIZE(setup_base->e820_map), setup_base->e820_map);
+	ret = sfi_write_tables();
+	if (ret && ret != -ENOSYS) {
+		printf("Failed to write SFI tables: err=%d\n", ret);
+		return ret;
+	}
 
 	if (bootproto == 0x0100) {
 		setup_base->screen_info.cl_magic = COMMAND_LINE_MAGIC;
diff --git a/include/linux/sfi.h b/include/linux/sfi.h
new file mode 100644
index 0000000..4094fc7
--- /dev/null
+++ b/include/linux/sfi.h
@@ -0,0 +1,139 @@
+/*
+ * Copyright(c) 2009 Intel Corporation. All rights reserved.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+	BSD-3-Clause
+ */
+
+#ifndef _LINUX_SFI_H
+#define _LINUX_SFI_H
+
+#include <errno.h>
+#include <linux/types.h>
+
+/* Table signatures reserved by the SFI specification */
+#define SFI_SIG_SYST		"SYST"
+#define SFI_SIG_FREQ		"FREQ"
+#define SFI_SIG_IDLE		"IDLE"
+#define SFI_SIG_CPUS		"CPUS"
+#define SFI_SIG_MTMR		"MTMR"
+#define SFI_SIG_MRTC		"MRTC"
+#define SFI_SIG_MMAP		"MMAP"
+#define SFI_SIG_APIC		"APIC"
+#define SFI_SIG_XSDT		"XSDT"
+#define SFI_SIG_WAKE		"WAKE"
+#define SFI_SIG_DEVS		"DEVS"
+#define SFI_SIG_GPIO		"GPIO"
+
+#define SFI_SIGNATURE_SIZE	4
+#define SFI_OEM_ID_SIZE		6
+#define SFI_OEM_TABLE_ID_SIZE	8
+
+#define SFI_NAME_LEN		16
+
+#define SFI_SYST_SEARCH_BEGIN		0x000e0000
+#define SFI_SYST_SEARCH_END		0x000fffff
+
+#define SFI_GET_NUM_ENTRIES(ptable, entry_type) \
+	((ptable->header.len - sizeof(struct sfi_table_header)) / \
+	(sizeof(entry_type)))
+
+/* Table structures must be byte-packed to match the SFI specification */
+struct sfi_table_header {
+	char	sig[SFI_SIGNATURE_SIZE];
+	u32	len;
+	u8	rev;
+	u8	csum;
+	char	oem_id[SFI_OEM_ID_SIZE];
+	char	oem_table_id[SFI_OEM_TABLE_ID_SIZE];
+} __packed;
+
+struct sfi_table_simple {
+	struct sfi_table_header		header;
+	u64				pentry[1];
+} __packed;
+
+/* Comply with UEFI spec 2.1 */
+struct sfi_mem_entry {
+	u32	type;
+	u64	phys_start;
+	u64	virt_start;
+	u64	pages;
+	u64	attrib;
+} __packed;
+
+struct sfi_cpu_table_entry {
+	u32	apic_id;
+} __packed;
+
+struct sfi_cstate_table_entry {
+	u32	hint;		/* MWAIT hint */
+	u32	latency;	/* latency in ms */
+} __packed;
+
+struct sfi_apic_table_entry {
+	u64	phys_addr;	/* phy base addr for APIC reg */
+} __packed;
+
+struct sfi_freq_table_entry {
+	u32	freq_mhz;	/* in MHZ */
+	u32	latency;	/* transition latency in ms */
+	u32	ctrl_val;	/* value to write to PERF_CTL */
+} __packed;
+
+struct sfi_wake_table_entry {
+	u64	phys_addr;	/* pointer to where the wake vector locates */
+} __packed;
+
+struct sfi_timer_table_entry {
+	u64	phys_addr;	/* phy base addr for the timer */
+	u32	freq_hz;	/* in HZ */
+	u32	irq;
+} __packed;
+
+struct sfi_rtc_table_entry {
+	u64	phys_addr;	/* phy base addr for the RTC */
+	u32	irq;
+} __packed;
+
+struct sfi_device_table_entry {
+	u8	type;		/* bus type, I2C, SPI or ...*/
+#define SFI_DEV_TYPE_SPI	0
+#define SFI_DEV_TYPE_I2C	1
+#define SFI_DEV_TYPE_UART	2
+#define SFI_DEV_TYPE_HSI	3
+#define SFI_DEV_TYPE_IPC	4
+
+	u8	host_num;	/* attached to host 0, 1...*/
+	u16	addr;
+	u8	irq;
+	u32	max_freq;
+	char	name[SFI_NAME_LEN];
+} __packed;
+
+struct sfi_gpio_table_entry {
+	char	controller_name[SFI_NAME_LEN];
+	u16	pin_no;
+	char	pin_name[SFI_NAME_LEN];
+} __packed;
+
+struct sfi_xsdt_header {
+	uint32_t oem_revision;
+	uint32_t creator_id;
+	uint32_t creator_revision;
+};
+
+typedef int (*sfi_table_handler) (struct sfi_table_header *table);
+
+#ifdef CONFIG_SFI
+/**
+ * sfi_write_tables() - Write Simple Firmware Interface tables
+ */
+int sfi_write_tables(void);
+
+#else
+
+static inline int sfi_write_tables(void) { return -ENOSYS; }
+
+#endif
+
+#endif /*_LINUX_SFI_H */
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 08/20] dm: Implement a CPU uclass

[Simon Glass]

It is useful to be able to keep track of the available CPUs in a multi-CPU
system. This uclass is mostly intended for use with SMP systems.

The uclass provides methods for getting basic information about each CPU.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 drivers/Kconfig          |  2 ++
 drivers/Makefile         |  1 +
 drivers/cpu/Kconfig      |  8 +++++
 drivers/cpu/Makefile     |  7 ++++
 drivers/cpu/cpu-uclass.c | 61 +++++++++++++++++++++++++++++++++++
 include/cpu.h            | 84 ++++++++++++++++++++++++++++++++++++++++++++++++
 include/dm/uclass-id.h   |  1 +
 7 files changed, 164 insertions(+)
 create mode 100644 drivers/cpu/Kconfig
 create mode 100644 drivers/cpu/Makefile
 create mode 100644 drivers/cpu/cpu-uclass.c
 create mode 100644 include/cpu.h

diff --git a/drivers/Kconfig b/drivers/Kconfig
index 941aa0c..1f40887 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -2,6 +2,8 @@ menu "Device Drivers"
 
 source "drivers/core/Kconfig"
 
+source "drivers/cpu/Kconfig"
+
 source "drivers/demo/Kconfig"
 
 source "drivers/pci/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index 5ef58c0..405b64b 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -3,6 +3,7 @@ obj-$(CONFIG_DM_DEMO) += demo/
 obj-$(CONFIG_BIOSEMU) += bios_emulator/
 obj-y += block/
 obj-$(CONFIG_BOOTCOUNT_LIMIT) += bootcount/
+obj-$(CONFIG_CPU) += cpu/
 obj-y += crypto/
 obj-$(CONFIG_FPGA) += fpga/
 obj-y += hwmon/
diff --git a/drivers/cpu/Kconfig b/drivers/cpu/Kconfig
new file mode 100644
index 0000000..23745e3
--- /dev/null
+++ b/drivers/cpu/Kconfig
@@ -0,0 +1,8 @@
+config CPU
+	bool "Enable CPU drivers using Driver Model"
+	help
+	  This allows drivers to be provided for CPUs and their type to be
+	  specified in the board's device tree. For boards which support
+	  multiple CPUs, they normally have to be set up in U-Boot so that
+	  they can work correctly in the OS. This provides a framework for
+	  finding out information about available CPUs and making changes.
diff --git a/drivers/cpu/Makefile b/drivers/cpu/Makefile
new file mode 100644
index 0000000..8710160
--- /dev/null
+++ b/drivers/cpu/Makefile
@@ -0,0 +1,7 @@
+#
+# Copyright (c) 2015 Google, Inc
+# Wolfgang Denk, DENX Software Engineering, wd at denx.de.
+#
+# SPDX-License-Identifier:      GPL-2.0+
+#
+obj-$(CONFIG_CPU) += cpu-uclass.o
diff --git a/drivers/cpu/cpu-uclass.c b/drivers/cpu/cpu-uclass.c
new file mode 100644
index 0000000..ab18ee2
--- /dev/null
+++ b/drivers/cpu/cpu-uclass.c
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2015 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <cpu.h>
+#include <dm.h>
+#include <dm/lists.h>
+#include <dm/root.h>
+
+int cpu_get_desc(struct udevice *dev, char *buf, int size)
+{
+	struct cpu_ops *ops = cpu_get_ops(dev);
+
+	if (!ops->get_desc)
+		return -ENOSYS;
+
+	return ops->get_desc(dev, buf, size);
+}
+
+int cpu_get_info(struct udevice *dev, struct cpu_info *info)
+{
+	struct cpu_ops *ops = cpu_get_ops(dev);
+
+	if (!ops->get_desc)
+		return -ENOSYS;
+
+	return ops->get_info(dev, info);
+}
+
+U_BOOT_DRIVER(cpu_bus) = {
+	.name	= "cpu_bus",
+	.id	= UCLASS_SIMPLE_BUS,
+	.per_child_platdata_auto_alloc_size = sizeof(struct cpu_platdata),
+};
+
+static int uclass_cpu_init(struct uclass *uc)
+{
+	struct udevice *dev;
+	int node;
+	int ret;
+
+	node = fdt_path_offset(gd->fdt_blob, "/cpus");
+	if (node < 0)
+		return 0;
+
+	ret = device_bind_driver_to_node(dm_root(), "cpu_bus", "cpus", node,
+					 &dev);
+
+	return ret;
+}
+
+UCLASS_DRIVER(cpu) = {
+	.id		= UCLASS_CPU,
+	.name		= "cpu",
+	.flags		= DM_UC_FLAG_SEQ_ALIAS,
+	.init		= uclass_cpu_init,
+};
diff --git a/include/cpu.h b/include/cpu.h
new file mode 100644
index 0000000..46467d0
--- /dev/null
+++ b/include/cpu.h
@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __cpu_h
+#define __cpu_h
+
+/**
+ * struct cpu_platdata - platform data for a CPU
+ *
+ * This can be accessed with dev_get_parent_platdata() for any UCLASS_CPU
+ * device.
+ *
+ * @cpu_id:	Platform-specific way of identifying the CPU.
+ */
+struct cpu_platdata {
+	int cpu_id;
+};
+
+/* CPU features - mostly just a placeholder for now */
+enum {
+	CPU_FEAT_L1_CACHE	= 0,	/* Supports level 1 cache */
+	CPU_FEAT_MMU		= 1,	/* Supports virtual memory */
+
+	CPU_FEAT_COUNT,
+};
+
+/**
+ * struct cpu_info - Information about a CPU
+ *
+ * @cpu_freq:	Current CPU frequency in Hz
+ * @features:	Flags for supported CPU features
+ */
+struct cpu_info {
+	ulong cpu_freq;
+	ulong features;
+};
+
+struct cpu_ops {
+	/**
+	 * get_desc() - Get a description string for a CPU
+	 *
+	 * @dev:	Device to check (UCLASS_CPU)
+	 * @buf:	Buffer to place string
+	 * @size:	Size of string space
+	 * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
+	 */
+	int (*get_desc)(struct udevice *dev, char *buf, int size);
+
+	/**
+	 * get_info() - Get information about a CPU
+	 *
+	 * @dev:	Device to check (UCLASS_CPU)
+	 * @info:	Returns CPU info
+	 * @return 0 if OK, -ve on error
+	 */
+	int (*get_info)(struct udevice *dev, struct cpu_info *info);
+};
+
+#define cpu_get_ops(dev)        ((struct cpu_ops *)(dev)->driver->ops)
+
+/**
+ * cpu_get_desc() - Get a description string for a CPU
+ *
+ * @dev:	Device to check (UCLASS_CPU)
+ * @buf:	Buffer to place string
+ * @size:	Size of string space
+ * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
+ */
+int cpu_get_desc(struct udevice *dev, char *buf, int size);
+
+/**
+ * get_info() - Get information about a CPU
+ *
+ * @dev:	Device to check (UCLASS_CPU)
+ * @info:	Returns CPU info
+ * @return 0 if OK, -ve on error
+ */
+int cpu_get_info(struct udevice *dev, struct cpu_info *info);
+
+#endif
diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
index fddfd35..395e25a 100644
--- a/include/dm/uclass-id.h
+++ b/include/dm/uclass-id.h
@@ -45,6 +45,7 @@ enum uclass_id {
 	UCLASS_USB_HUB,		/* USB hub */
 	UCLASS_USB_DEV_GENERIC,	/* USB generic device */
 	UCLASS_MASS_STORAGE,	/* Mass storage device */
+	UCLASS_CPU,		/* CPU, typically part of an SoC */
 
 	UCLASS_COUNT,
 	UCLASS_INVALID = -1,
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 09/20] Add a 'cpu' command to print CPU information

[Simon Glass]

Add a simple command which provides access to a list of available CPUs along
with descriptions and basic information.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 common/Kconfig   |   8 ++++
 common/Makefile  |   1 +
 common/cmd_cpu.c | 113 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 122 insertions(+)
 create mode 100644 common/cmd_cpu.c

diff --git a/common/Kconfig b/common/Kconfig
index 5d7e48a..15759f7 100644
--- a/common/Kconfig
+++ b/common/Kconfig
@@ -31,6 +31,14 @@ config CMD_CONSOLE
 	help
 	  Print console devices and information.
 
+config CMD_CPU
+	bool "cpu"
+	help
+	  Print information about available CPUs. This normally shows the
+	  number of CPUs, type (e.g. manufacturer, architecture, product or
+	  internal name) and clock frequency. Other information may be
+	  available depending on the CPU driver.
+
 config CMD_LICENSE
 	bool "license"
 	help
diff --git a/common/Makefile b/common/Makefile
index fba3830..9084c73 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -74,6 +74,7 @@ obj-$(CONFIG_CMD_CBFS) += cmd_cbfs.o
 obj-$(CONFIG_CMD_CLK) += cmd_clk.o
 obj-$(CONFIG_CMD_CONSOLE) += cmd_console.o
 obj-$(CONFIG_CMD_CPLBINFO) += cmd_cplbinfo.o
+obj-$(CONFIG_CMD_CPU) += cmd_cpu.o
 obj-$(CONFIG_DATAFLASH_MMC_SELECT) += cmd_dataflash_mmc_mux.o
 obj-$(CONFIG_CMD_DATE) += cmd_date.o
 obj-$(CONFIG_CMD_DEMO) += cmd_demo.o
diff --git a/common/cmd_cpu.c b/common/cmd_cpu.c
new file mode 100644
index 0000000..c3e229f
--- /dev/null
+++ b/common/cmd_cpu.c
@@ -0,0 +1,113 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <command.h>
+#include <cpu.h>
+#include <dm.h>
+
+static const char *cpu_feature_name[CPU_FEAT_COUNT] = {
+	"L1 cache",
+	"MMU",
+};
+
+static int print_cpu_list(bool detail)
+{
+	struct udevice *dev;
+	struct uclass *uc;
+	char buf[100];
+	int ret;
+
+	ret = uclass_get(UCLASS_CPU, &uc);
+	if (ret) {
+		printf("Cannot find CPU uclass\n");
+		return ret;
+	}
+	uclass_foreach_dev(dev, uc) {
+		struct cpu_platdata *plat = dev_get_parent_platdata(dev);
+		struct cpu_info info;
+		bool first;
+		int i;
+
+		ret = cpu_get_desc(dev, buf, sizeof(buf));
+		printf("%3d: %-10s %s\n", dev->seq, dev->name,
+		       ret ? "<no description>" : buf);
+		if (!detail)
+			continue;
+		ret = cpu_get_info(dev, &info);
+		if (ret) {
+			printf("\t(no detail available");
+			if (ret != -ENOSYS)
+				printf(": err=%d\n", ret);
+			printf(")\n");
+			continue;
+		}
+		printf("\tID = %d, freq = ", plat->cpu_id);
+		print_freq(info.cpu_freq, "");
+		first = true;
+		for (i = 0; i < CPU_FEAT_COUNT; i++) {
+			if (info.features & (1 << i)) {
+				printf("%s%s", first ? ": " : ", ",
+				       cpu_feature_name[i]);
+				first = false;
+			}
+		}
+		printf("\n");
+	}
+
+	return 0;
+}
+
+static int do_cpu_list(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
+{
+	if (print_cpu_list(false))
+		return CMD_RET_FAILURE;
+
+	return 0;
+}
+
+static int do_cpu_detail(cmd_tbl_t *cmdtp, int flag, int argc,
+			 char *const argv[])
+{
+	if (print_cpu_list(true))
+		return CMD_RET_FAILURE;
+
+	return 0;
+}
+
+static cmd_tbl_t cmd_cpu_sub[] = {
+	U_BOOT_CMD_MKENT(list, 2, 1, do_cpu_list, "", ""),
+	U_BOOT_CMD_MKENT(detail, 4, 0, do_cpu_detail, "", ""),
+};
+
+/*
+ * Process a cpu sub-command
+ */
+static int do_cpu(cmd_tbl_t *cmdtp, int flag, int argc,
+		       char * const argv[])
+{
+	cmd_tbl_t *c = NULL;
+
+	/* Strip off leading 'cpu' command argument */
+	argc--;
+	argv++;
+
+	if (argc)
+		c = find_cmd_tbl(argv[0], cmd_cpu_sub, ARRAY_SIZE(cmd_cpu_sub));
+
+	if (c)
+		return c->cmd(cmdtp, flag, argc, argv);
+	else
+		return CMD_RET_USAGE;
+}
+
+U_BOOT_CMD(
+	cpu, 2, 1, do_cpu,
+	"display information about CPUs",
+	"list	- list available CPUs\n"
+	"cpu detail	- show CPU detail"
+);
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 10/20] x86: Add atomic operations

[Simon Glass]

Add a subset of this header file from Linux 4.0 to support atomic operations
in U-Boot.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 arch/x86/include/asm/atomic.h | 115 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 115 insertions(+)
 create mode 100644 arch/x86/include/asm/atomic.h

diff --git a/arch/x86/include/asm/atomic.h b/arch/x86/include/asm/atomic.h
new file mode 100644
index 0000000..806f787
--- /dev/null
+++ b/arch/x86/include/asm/atomic.h
@@ -0,0 +1,115 @@
+#ifndef _ASM_X86_ATOMIC_H
+#define _ASM_X86_ATOMIC_H
+
+#include <linux/compiler.h>
+#include <linux/types.h>
+#include <asm/processor.h>
+
+typedef struct { volatile int counter; } atomic_t;
+
+/*
+ * Atomic operations that C can't guarantee us.  Useful for
+ * resource counting etc..
+ */
+
+#define ATOMIC_INIT(i)	{ (i) }
+
+/**
+ * atomic_read - read atomic variable
+ * @v: pointer of type atomic_t
+ *
+ * Atomically reads the value of @v.
+ */
+static inline int atomic_read(const atomic_t *v)
+{
+	return ACCESS_ONCE((v)->counter);
+}
+
+/**
+ * atomic_set - set atomic variable
+ * @v: pointer of type atomic_t
+ * @i: required value
+ *
+ * Atomically sets the value of @v to @i.
+ */
+static inline void atomic_set(atomic_t *v, int i)
+{
+	v->counter = i;
+}
+
+/**
+ * atomic_add - add integer to atomic variable
+ * @i: integer value to add
+ * @v: pointer of type atomic_t
+ *
+ * Atomically adds @i to @v.
+ */
+static inline void atomic_add(int i, atomic_t *v)
+{
+	asm volatile(LOCK_PREFIX "addl %1,%0"
+		     : "+m" (v->counter)
+		     : "ir" (i));
+}
+
+/**
+ * atomic_sub - subtract integer from atomic variable
+ * @i: integer value to subtract
+ * @v: pointer of type atomic_t
+ *
+ * Atomically subtracts @i from @v.
+ */
+static inline void atomic_sub(int i, atomic_t *v)
+{
+	asm volatile(LOCK_PREFIX "subl %1,%0"
+		     : "+m" (v->counter)
+		     : "ir" (i));
+}
+
+/**
+ * atomic_inc - increment atomic variable
+ * @v: pointer of type atomic_t
+ *
+ * Atomically increments @v by 1.
+ */
+static inline void atomic_inc(atomic_t *v)
+{
+	asm volatile(LOCK_PREFIX "incl %0"
+		     : "+m" (v->counter));
+}
+
+/**
+ * atomic_dec - decrement atomic variable
+ * @v: pointer of type atomic_t
+ *
+ * Atomically decrements @v by 1.
+ */
+static inline void atomic_dec(atomic_t *v)
+{
+	asm volatile(LOCK_PREFIX "decl %0"
+		     : "+m" (v->counter));
+}
+
+/**
+ * atomic_inc_short - increment of a short integer
+ * @v: pointer to type int
+ *
+ * Atomically adds 1 to @v
+ * Returns the new value of @u
+ */
+static inline short int atomic_inc_short(short int *v)
+{
+	asm(LOCK_PREFIX "addw $1, %0" : "+m" (*v));
+	return *v;
+}
+
+/* These are x86-specific, used by some header files */
+#define atomic_clear_mask(mask, addr)				\
+	asm volatile(LOCK_PREFIX "andl %0,%1"			\
+		     : : "r" (~(mask)), "m" (*(addr)) : "memory")
+
+#define atomic_set_mask(mask, addr)				\
+	asm volatile(LOCK_PREFIX "orl %0,%1"			\
+		     : : "r" ((unsigned)(mask)), "m" (*(addr))	\
+		     : "memory")
+
+#endif /* _ASM_X86_ATOMIC_H */
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 11/20] x86: Add defines for fixed MTRRs

[Simon Glass]

Add MSR numbers for the fixed MTRRs.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 arch/x86/include/asm/mtrr.h | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
index fda4eae..3841593 100644
--- a/arch/x86/include/asm/mtrr.h
+++ b/arch/x86/include/asm/mtrr.h
@@ -34,6 +34,20 @@
 /* Number of MTRRs supported */
 #define MTRR_COUNT		8
 
+#define NUM_FIXED_RANGES 88
+#define RANGES_PER_FIXED_MTRR 8
+#define MTRR_FIX_64K_00000_MSR 0x250
+#define MTRR_FIX_16K_80000_MSR 0x258
+#define MTRR_FIX_16K_A0000_MSR 0x259
+#define MTRR_FIX_4K_C0000_MSR 0x268
+#define MTRR_FIX_4K_C8000_MSR 0x269
+#define MTRR_FIX_4K_D0000_MSR 0x26a
+#define MTRR_FIX_4K_D8000_MSR 0x26b
+#define MTRR_FIX_4K_E0000_MSR 0x26c
+#define MTRR_FIX_4K_E8000_MSR 0x26d
+#define MTRR_FIX_4K_F0000_MSR 0x26e
+#define MTRR_FIX_4K_F8000_MSR 0x26f
+
 #if !defined(__ASSEMBLER__)
 
 /**
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 12/20] x86: Add an mfence macro

[Simon Glass]

Provide access to this x86 instruction from C code.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 arch/x86/include/asm/cpu.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
index c839291..37aa6b9 100644
--- a/arch/x86/include/asm/cpu.h
+++ b/arch/x86/include/asm/cpu.h
@@ -151,6 +151,11 @@ static inline int flag_is_changeable_p(uint32_t flag)
 	return ((f1^f2) & flag) != 0;
 }
 
+static inline void mfence(void)
+{
+	__asm__ __volatile__("mfence\t\n" : : : "memory");
+}
+
 /**
  * cpu_enable_paging_pae() - Enable PAE-paging
  *
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 13/20] x86: Store the GDT pointer in global_data

[Simon Glass]

When we start up additional CPUs we want them to use the same Global
Descriptor Table. Store the address of this in global_data so we can
reference it later.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 arch/x86/cpu/cpu.c                 | 1 +
 arch/x86/include/asm/global_data.h | 1 +
 2 files changed, 2 insertions(+)

diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c
index 13b3baa..74bfed2 100644
--- a/arch/x86/cpu/cpu.c
+++ b/arch/x86/cpu/cpu.c
@@ -133,6 +133,7 @@ static void load_gdt(const u64 *boot_gdt, u16 num_entries)
 
 void setup_gdt(gd_t *id, u64 *gdt_addr)
 {
+	id->arch.gdt = gdt_addr;
 	/* CS: code, read/execute, 4 GB, base 0 */
 	gdt_addr[X86_GDT_ENTRY_32BIT_CS] = GDT_ENTRY(0xc09b, 0, 0xfffff);
 
diff --git a/arch/x86/include/asm/global_data.h b/arch/x86/include/asm/global_data.h
index 5ee06eb..4d9eac6 100644
--- a/arch/x86/include/asm/global_data.h
+++ b/arch/x86/include/asm/global_data.h
@@ -68,6 +68,7 @@ struct arch_global_data {
 	/* MRC training data to save for the next boot */
 	char *mrc_output;
 	unsigned int mrc_output_len;
+	void *gdt;			/* Global descriptor table */
 };
 
 #endif
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 14/20] x86: Provide access to the IDT

[Simon Glass]

Add a function to return the address of the Interrupt Descriptor Table.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 arch/x86/cpu/interrupts.c        | 5 +++++
 arch/x86/include/asm/interrupt.h | 2 ++
 2 files changed, 7 insertions(+)

diff --git a/arch/x86/cpu/interrupts.c b/arch/x86/cpu/interrupts.c
index a21d2a6..c777d36 100644
--- a/arch/x86/cpu/interrupts.c
+++ b/arch/x86/cpu/interrupts.c
@@ -147,6 +147,11 @@ int cpu_init_interrupts(void)
 	return 0;
 }
 
+void *x86_get_idt(void)
+{
+	return &idt_ptr;
+}
+
 void __do_irq(int irq)
 {
 	printf("Unhandled IRQ : %d\n", irq);
diff --git a/arch/x86/include/asm/interrupt.h b/arch/x86/include/asm/interrupt.h
index 25abde7..0a75f89 100644
--- a/arch/x86/include/asm/interrupt.h
+++ b/arch/x86/include/asm/interrupt.h
@@ -38,4 +38,6 @@ extern char exception_stack[];
  */
 void configure_irq_trigger(int int_num, bool is_level_triggered);
 
+void *x86_get_idt(void);
+
 #endif
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 15/20] x86: Add multi-processor init

[Simon Glass]

Most modern x86 CPUs include more than one CPU core. The OS normally requires
that these 'Application Processors' (APs) be brought up by the boot loader.
Add the required support to U-Boot to init additional APs.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 arch/x86/Kconfig                     |  25 ++
 arch/x86/cpu/Makefile                |   2 +
 arch/x86/cpu/ivybridge/model_206ax.c |   4 +-
 arch/x86/cpu/mp_init.c               | 507 +++++++++++++++++++++++++++++++++++
 arch/x86/cpu/sipi.S                  | 217 +++++++++++++++
 arch/x86/include/asm/mp.h            |  94 +++++++
 arch/x86/include/asm/sipi.h          |  79 ++++++
 arch/x86/include/asm/smm.h           |  14 +
 8 files changed, 940 insertions(+), 2 deletions(-)
 create mode 100644 arch/x86/cpu/mp_init.c
 create mode 100644 arch/x86/cpu/sipi.S
 create mode 100644 arch/x86/include/asm/mp.h
 create mode 100644 arch/x86/include/asm/sipi.h
 create mode 100644 arch/x86/include/asm/smm.h

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 30a08ec..ae0e05f 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -422,6 +422,31 @@ source "arch/x86/cpu/quark/Kconfig"
 
 source "arch/x86/cpu/queensbay/Kconfig"
 
+config MAX_CPUS
+        int "Maximum number of CPUs permitted"
+        default 4
+        help
+          When using multi-CPU chips it is possible for U-Boot to start up
+          more than one CPU. The stack memory used by all of these CPUs is
+          pre-allocated so at present U-Boot wants to know the maximum
+          number of CPUs that may be present. Set this to at least as high
+          as the number of CPUs in your system (it uses about 4KB of RAM for
+          each CPU).
+
+config SMP
+	bool "Enable Symmetric Multiprocessing"
+	default n
+	help
+	  Enable use of more than one CPU in U-Boot and the Operating System
+	  when loaded. Each CPU will be started up and information can be
+	  obtained using the 'cpu' command. If this option is disabled, then
+	  only one CPU will be enabled regardless of the number of CPUs
+	  available.
+
+config STACK_SIZE
+	hex
+	default 0x1000
+
 config TSC_CALIBRATION_BYPASS
 	bool "Bypass Time-Stamp Counter (TSC) calibration"
 	default n
diff --git a/arch/x86/cpu/Makefile b/arch/x86/cpu/Makefile
index 6ded0a7..9a08ab4 100644
--- a/arch/x86/cpu/Makefile
+++ b/arch/x86/cpu/Makefile
@@ -19,6 +19,8 @@ obj-$(CONFIG_NORTHBRIDGE_INTEL_IVYBRIDGE) += ivybridge/
 obj-$(CONFIG_INTEL_QUARK) += quark/
 obj-$(CONFIG_INTEL_QUEENSBAY) += queensbay/
 obj-y += lapic.o
+obj-$(CONFIG_SMP) += mp_init.o
 obj-y += mtrr.o
 obj-$(CONFIG_PCI) += pci.o
+obj-$(CONFIG_SMP) += sipi.o
 obj-y += turbo.o
diff --git a/arch/x86/cpu/ivybridge/model_206ax.c b/arch/x86/cpu/ivybridge/model_206ax.c
index 11dc625..8b08c40 100644
--- a/arch/x86/cpu/ivybridge/model_206ax.c
+++ b/arch/x86/cpu/ivybridge/model_206ax.c
@@ -435,8 +435,8 @@ static int intel_cores_init(struct x86_cpu_priv *cpu)
 
 		debug("CPU: %u has core %u\n", cpu->apic_id, new_cpu->apic_id);
 
-#if CONFIG_SMP && CONFIG_MAX_CPUS > 1
-		/* Start the new cpu */
+#if 0 && CONFIG_SMP && CONFIG_MAX_CPUS > 1
+		/* TODO(sjg at chromium.org): Start the new cpu */
 		if (!start_cpu(new_cpu)) {
 			/* Record the error in cpu? */
 			printk(BIOS_ERR, "CPU %u would not start!\n",
diff --git a/arch/x86/cpu/mp_init.c b/arch/x86/cpu/mp_init.c
new file mode 100644
index 0000000..f660c9d
--- /dev/null
+++ b/arch/x86/cpu/mp_init.c
@@ -0,0 +1,507 @@
+/*
+ * Copyright (C) 2015 Google, Inc
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ *
+ * Based on code from the coreboot file of the same name
+ */
+
+#include <common.h>
+#include <cpu.h>
+#include <dm.h>
+#include <errno.h>
+#include <malloc.h>
+#include <asm/atomic.h>
+#include <asm/cpu.h>
+#include <asm/interrupt.h>
+#include <asm/lapic.h>
+#include <asm/mp.h>
+#include <asm/mtrr.h>
+#include <asm/sipi.h>
+#include <asm/smm.h>
+#include <dm/device-internal.h>
+#include <dm/uclass-internal.h>
+#include <linux/linkage.h>
+
+/* This also needs to match the sipi.S assembly code for saved MSR encoding */
+struct saved_msr {
+	uint32_t index;
+	uint32_t lo;
+	uint32_t hi;
+} __packed;
+
+
+/*
+ * The SIPI vector is loaded at the SMM_DEFAULT_BASE. The reason is that the
+ * memory range is already reserved so the OS cannot use it. That region is
+ * free to use for AP bringup before SMM is initialised.
+ */
+static const uint32_t sipi_vector_location = SMM_DEFAULT_BASE;
+static const int sipi_vector_location_size = SMM_DEFAULT_SIZE;
+
+struct mp_flight_plan {
+	int num_records;
+	struct mp_flight_record *records;
+};
+
+static struct mp_flight_plan mp_info;
+
+struct cpu_map {
+	struct udevice *dev;
+	int apic_id;
+	int err_code;
+};
+
+static inline void barrier_wait(atomic_t *b)
+{
+	while (atomic_read(b) == 0)
+		asm("pause");
+	mfence();
+}
+
+static inline void release_barrier(atomic_t *b)
+{
+	mfence();
+	atomic_set(b, 1);
+}
+
+/* Returns 1 if timeout waiting for APs. 0 if target APs found */
+static int wait_for_aps(atomic_t *val, int target, int total_delay,
+			int delay_step)
+{
+	int timeout = 0;
+	int delayed = 0;
+
+	while (atomic_read(val) != target) {
+		udelay(delay_step);
+		delayed += delay_step;
+		if (delayed >= total_delay) {
+			timeout = 1;
+			break;
+		}
+	}
+
+	return timeout;
+}
+
+static void ap_do_flight_plan(struct udevice *cpu)
+{
+	int i;
+
+	for (i = 0; i < mp_info.num_records; i++) {
+		struct mp_flight_record *rec = &mp_info.records[i];
+
+		atomic_inc(&rec->cpus_entered);
+		barrier_wait(&rec->barrier);
+
+		if (rec->ap_call != NULL)
+			rec->ap_call(cpu, rec->ap_arg);
+	}
+}
+
+static int find_cpu_by_apid_id(int apic_id, struct udevice **devp)
+{
+	struct udevice *dev;
+
+	*devp = NULL;
+	for (uclass_find_first_device(UCLASS_CPU, &dev);
+	     dev;
+	     uclass_find_next_device(&dev)) {
+		struct cpu_platdata *plat = dev_get_parent_platdata(dev);
+
+		if (plat->cpu_id == apic_id) {
+			*devp = dev;
+			return 0;
+		}
+	}
+
+	return -ENOENT;
+}
+
+/*
+ * By the time APs call ap_init() caching has been setup, and microcode has
+ * been loaded
+ */
+static void asmlinkage ap_init(unsigned int cpu_index)
+{
+	struct udevice *dev;
+	int apic_id;
+	int ret;
+
+	/* Ensure the local apic is enabled */
+	enable_lapic();
+
+	apic_id = lapicid();
+	ret = find_cpu_by_apid_id(apic_id, &dev);
+	if (ret) {
+		debug("Unknown CPU apic_id %x\n", apic_id);
+		goto done;
+	}
+
+	debug("AP: slot %d apic_id %x, dev %s\n", cpu_index, apic_id,
+	      dev ? dev->name : "(apic_id not found)");
+
+	/* Walk the flight plan */
+	ap_do_flight_plan(dev);
+
+	/* Park the AP */
+	debug("parking\n");
+done:
+	stop_this_cpu();
+}
+
+#define NUM_FIXED_MTRRS 11
+
+static const unsigned int fixed_mtrrs[NUM_FIXED_MTRRS] = {
+	MTRR_FIX_64K_00000_MSR, MTRR_FIX_16K_80000_MSR, MTRR_FIX_16K_A0000_MSR,
+	MTRR_FIX_4K_C0000_MSR, MTRR_FIX_4K_C8000_MSR, MTRR_FIX_4K_D0000_MSR,
+	MTRR_FIX_4K_D8000_MSR, MTRR_FIX_4K_E0000_MSR, MTRR_FIX_4K_E8000_MSR,
+	MTRR_FIX_4K_F0000_MSR, MTRR_FIX_4K_F8000_MSR,
+};
+
+static inline struct saved_msr *save_msr(int index, struct saved_msr *entry)
+{
+	msr_t msr;
+
+	msr = msr_read(index);
+	entry->index = index;
+	entry->lo = msr.lo;
+	entry->hi = msr.hi;
+
+	/* Return the next entry */
+	entry++;
+	return entry;
+}
+
+static int save_bsp_msrs(char *start, int size)
+{
+	int msr_count;
+	int num_var_mtrrs;
+	struct saved_msr *msr_entry;
+	int i;
+	msr_t msr;
+
+	/* Determine number of MTRRs need to be saved */
+	msr = msr_read(MTRR_CAP_MSR);
+	num_var_mtrrs = msr.lo & 0xff;
+
+	/* 2 * num_var_mtrrs for base and mask. +1 for IA32_MTRR_DEF_TYPE */
+	msr_count = 2 * num_var_mtrrs + NUM_FIXED_MTRRS + 1;
+
+	if ((msr_count * sizeof(struct saved_msr)) > size) {
+		printf("Cannot mirror all %d msrs.\n", msr_count);
+		return -ENOSPC;
+	}
+
+	msr_entry = (void *)start;
+	for (i = 0; i < NUM_FIXED_MTRRS; i++)
+		msr_entry = save_msr(fixed_mtrrs[i], msr_entry);
+
+	for (i = 0; i < num_var_mtrrs; i++) {
+		msr_entry = save_msr(MTRR_PHYS_BASE_MSR(i), msr_entry);
+		msr_entry = save_msr(MTRR_PHYS_MASK_MSR(i), msr_entry);
+	}
+
+	msr_entry = save_msr(MTRR_DEF_TYPE_MSR, msr_entry);
+
+	return msr_count;
+}
+
+static int load_sipi_vector(atomic_t **ap_countp)
+{
+	struct sipi_params_16bit *params16;
+	struct sipi_params *params;
+	static char msr_save[512];
+	char *stack;
+	ulong addr;
+	int code_len;
+	int size;
+	int ret;
+
+	/* Copy in the code */
+	code_len = ap_start16_code_end - ap_start16;
+	debug("Copying SIPI code to %x: %d bytes\n", SMM_DEFAULT_BASE,
+	      code_len);
+	memcpy((void *)SMM_DEFAULT_BASE, ap_start16, code_len);
+
+	addr = SMM_DEFAULT_BASE + (ulong)sipi_params_16bit - (ulong)ap_start16;
+	params16 = (struct sipi_params_16bit *)addr;
+	params16->ap_start = (uint32_t)ap_start;
+	params16->gdt = (uint32_t)gd->arch.gdt;
+	params16->gdt_limit = X86_GDT_SIZE - 1;
+	debug("gdt = %x, gdt_limit = %x\n", params16->gdt, params16->gdt_limit);
+
+	params = (struct sipi_params *)sipi_params;
+	debug("SIPI 32-bit params at %p\n", params);
+	params->idt_ptr = (uint32_t)x86_get_idt();
+
+	params->stack_size = 4096;
+	size = params->stack_size * CONFIG_MAX_CPUS;
+	stack = memalign(size, 4096);
+	if (!stack)
+		return -ENOMEM;
+	params->stack_top = (u32)(stack + size);
+
+	params->microcode_ptr = 0;
+	params->msr_table_ptr = (u32)msr_save;
+	ret = save_bsp_msrs(msr_save, sizeof(msr_save));
+	if (ret < 0)
+		return ret;
+	params->msr_count = ret;
+
+	params->c_handler = (uint32_t)&ap_init;
+
+	*ap_countp = &params->ap_count;
+	atomic_set(*ap_countp, 0);
+	debug("SIPI vector is ready\n");
+
+	return 0;
+}
+
+static int check_cpu_devices(int expected_cpus)
+{
+	int i;
+
+	for (i = 0; i < expected_cpus; i++) {
+		struct udevice *dev;
+		int ret;
+
+		ret = uclass_find_device(UCLASS_CPU, i, &dev);
+		if (ret) {
+			debug("Cannot find CPU %d in device tree\n", i);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+/* Returns 1 for timeout. 0 on success */
+static int apic_wait_timeout(int total_delay, int delay_step)
+{
+	int total = 0;
+	int timeout = 0;
+
+	while (lapic_read(LAPIC_ICR) & LAPIC_ICR_BUSY) {
+		udelay(delay_step);
+		total += delay_step;
+		if (total >= total_delay) {
+			timeout = 1;
+			break;
+		}
+	}
+
+	return timeout;
+}
+
+static int start_aps(int ap_count, atomic_t *num_aps)
+{
+	int sipi_vector;
+	/* Max location is 4KiB below 1MiB */
+	const int max_vector_loc = ((1 << 20) - (1 << 12)) >> 12;
+
+	if (ap_count == 0)
+		return 0;
+
+	/* The vector is sent as a 4k aligned address in one byte */
+	sipi_vector = sipi_vector_location >> 12;
+
+	if (sipi_vector > max_vector_loc) {
+		printf("SIPI vector too large! 0x%08x\n",
+		       sipi_vector);
+		return -1;
+	}
+
+	debug("Attempting to start %d APs\n", ap_count);
+
+	if ((lapic_read(LAPIC_ICR) & LAPIC_ICR_BUSY)) {
+		debug("Waiting for ICR not to be busy...");
+		if (apic_wait_timeout(1000 /* 1 ms */, 50)) {
+			debug("timed out. Aborting.\n");
+			return -1;
+		} else {
+			debug("done.\n");
+		}
+	}
+
+	/* Send INIT IPI to all but self */
+	lapic_write_around(LAPIC_ICR2, SET_LAPIC_DEST_FIELD(0));
+	lapic_write_around(LAPIC_ICR, LAPIC_DEST_ALLBUT | LAPIC_INT_ASSERT |
+			   LAPIC_DM_INIT);
+	debug("Waiting for 10ms after sending INIT.\n");
+	mdelay(10);
+
+	/* Send 1st SIPI */
+	if ((lapic_read(LAPIC_ICR) & LAPIC_ICR_BUSY)) {
+		debug("Waiting for ICR not to be busy...");
+		if (apic_wait_timeout(1000 /* 1 ms */, 50)) {
+			debug("timed out. Aborting.\n");
+			return -1;
+		} else {
+			debug("done.\n");
+		}
+	}
+
+	lapic_write_around(LAPIC_ICR2, SET_LAPIC_DEST_FIELD(0));
+	lapic_write_around(LAPIC_ICR, LAPIC_DEST_ALLBUT | LAPIC_INT_ASSERT |
+			   LAPIC_DM_STARTUP | sipi_vector);
+	debug("Waiting for 1st SIPI to complete...");
+	if (apic_wait_timeout(10000 /* 10 ms */, 50 /* us */)) {
+		debug("timed out.\n");
+		return -1;
+	} else {
+		debug("done.\n");
+	}
+
+	/* Wait for CPUs to check in up to 200 us */
+	wait_for_aps(num_aps, ap_count, 200 /* us */, 15 /* us */);
+
+	/* Send 2nd SIPI */
+	if ((lapic_read(LAPIC_ICR) & LAPIC_ICR_BUSY)) {
+		debug("Waiting for ICR not to be busy...");
+		if (apic_wait_timeout(1000 /* 1 ms */, 50)) {
+			debug("timed out. Aborting.\n");
+			return -1;
+		} else {
+			debug("done.\n");
+		}
+	}
+
+	lapic_write_around(LAPIC_ICR2, SET_LAPIC_DEST_FIELD(0));
+	lapic_write_around(LAPIC_ICR, LAPIC_DEST_ALLBUT | LAPIC_INT_ASSERT |
+			   LAPIC_DM_STARTUP | sipi_vector);
+	debug("Waiting for 2nd SIPI to complete...");
+	if (apic_wait_timeout(10000 /* 10 ms */, 50 /* us */)) {
+		debug("timed out.\n");
+		return -1;
+	} else {
+		debug("done.\n");
+	}
+
+	/* Wait for CPUs to check in */
+	if (wait_for_aps(num_aps, ap_count, 10000 /* 10 ms */, 50 /* us */)) {
+		debug("Not all APs checked in: %d/%d.\n",
+		      atomic_read(num_aps), ap_count);
+		return -1;
+	}
+
+	return 0;
+}
+
+static int bsp_do_flight_plan(struct udevice *cpu, struct mp_params *mp_params)
+{
+	int i;
+	int ret = 0;
+	const int timeout_us = 100000;
+	const int step_us = 100;
+	int num_aps = mp_params->num_cpus - 1;
+
+	for (i = 0; i < mp_params->num_records; i++) {
+		struct mp_flight_record *rec = &mp_params->flight_plan[i];
+
+		/* Wait for APs if the record is not released */
+		if (atomic_read(&rec->barrier) == 0) {
+			/* Wait for the APs to check in */
+			if (wait_for_aps(&rec->cpus_entered, num_aps,
+					 timeout_us, step_us)) {
+				debug("MP record %d timeout.\n", i);
+				ret = -1;
+			}
+		}
+
+		if (rec->bsp_call != NULL)
+			rec->bsp_call(cpu, rec->bsp_arg);
+
+		release_barrier(&rec->barrier);
+	}
+	return ret;
+}
+
+static int init_bsp(struct udevice **devp)
+{
+	char processor_name[CPU_MAX_NAME_LEN];
+	int apic_id;
+	int ret;
+
+	cpu_get_name(processor_name);
+	debug("CPU: %s.\n", processor_name);
+
+	enable_lapic();
+
+	apic_id = lapicid();
+	ret = find_cpu_by_apid_id(apic_id, devp);
+	if (ret) {
+		printf("Cannot find boot CPU, APIC ID %d\n", apic_id);
+		return ret;
+	}
+
+	return 0;
+}
+
+int mp_init(struct mp_params *p)
+{
+	int num_aps;
+	atomic_t *ap_count;
+	struct udevice *cpu;
+	int ret;
+
+	/* This will cause the CPUs devices to be bound */
+	struct uclass *uc;
+	ret = uclass_get(UCLASS_CPU, &uc);
+	if (ret)
+		return ret;
+
+	ret = init_bsp(&cpu);
+	if (ret) {
+		debug("Cannot init boot CPU: err=%d\n", ret);
+		return ret;
+	}
+
+	if (p == NULL || p->flight_plan == NULL || p->num_records < 1) {
+		printf("Invalid MP parameters\n");
+		return -1;
+	}
+
+	ret = check_cpu_devices(p->num_cpus);
+	if (ret)
+		debug("Warning: Device tree does not describe all CPUs. Extra ones will not be started correctly\n");
+
+	/* Copy needed parameters so that APs have a reference to the plan */
+	mp_info.num_records = p->num_records;
+	mp_info.records = p->flight_plan;
+
+	/* Load the SIPI vector */
+	ret = load_sipi_vector(&ap_count);
+	if (ap_count == NULL)
+		return -1;
+
+	/*
+	 * Make sure SIPI data hits RAM so the APs that come up will see
+	 * the startup code even if the caches are disabled
+	 */
+	wbinvd();
+
+	/* Start the APs providing number of APs and the cpus_entered field */
+	num_aps = p->num_cpus - 1;
+	ret = start_aps(num_aps, ap_count);
+	if (ret) {
+		mdelay(1000);
+		debug("%d/%d eventually checked in?\n", atomic_read(ap_count),
+		      num_aps);
+		return ret;
+	}
+
+	/* Walk the flight plan for the BSP */
+	ret = bsp_do_flight_plan(cpu, p);
+	if (ret) {
+		debug("CPU init failed: err=%d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+int mp_init_cpu(struct udevice *cpu, void *unused)
+{
+	return device_probe(cpu);
+}
diff --git a/arch/x86/cpu/sipi.S b/arch/x86/cpu/sipi.S
new file mode 100644
index 0000000..34747de
--- /dev/null
+++ b/arch/x86/cpu/sipi.S
@@ -0,0 +1,217 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ *
+ * SPDX-License-Identifier:	GPL-2.0
+ *
+ * Taken from coreboot file of the same name
+ */
+
+/*
+ * The SIPI vector is responsible for initializing the APs in the sytem. It
+ * loads microcode, sets up MSRs, and enables caching before calling into
+ * C code
+ */
+
+#include <asm/global_data.h>
+#include <asm/msr-index.h>
+#include <asm/processor.h>
+#include <asm/processor-flags.h>
+#include <asm/smm.h>
+
+#define CODE_SEG	(X86_GDT_ENTRY_32BIT_CS * X86_GDT_ENTRY_SIZE)
+#define DATA_SEG	(X86_GDT_ENTRY_32BIT_DS * X86_GDT_ENTRY_SIZE)
+
+#define o32		.byte 0x66;
+
+/*
+ * First we have the 16-bit section. Every AP process starts here.
+ * The simple task is to load U-Boot's Global Descriptor Table (GDT) to allow
+ * U-Boot's 32-bit code to become visible, then jump to ap_start.
+ *
+ * Note that this code is copied to RAM below 1MB in mp_init.c, and runs from
+ * there, but the 32-bit code (ap_start and onwards) is part of U-Boot and
+ * is therefore relocated to the top of RAM with other U-Boot code. This
+ * means that for the 16-bit code we must write relocatable code, but for the
+ * rest, we can do what we like.
+ */
+.text
+.code16
+.globl ap_start16
+ap_start16:
+	cli
+	xorl	%eax, %eax
+	movl	%eax, %cr3		/* Invalidate TLB */
+
+	/* setup the data segment */
+	movw	%cs, %ax
+	movw	%ax, %ds
+
+	/* Use an address relative to the data segment for the GDT */
+	movl	$gdtaddr, %ebx
+	subl	$ap_start16, %ebx
+
+	data32 lgdt (%ebx)
+
+	movl	%cr0, %eax
+	andl	$0x7ffaffd1, %eax	/* PG, AM, WP, NE, TS, EM, MP = 0 */
+	orl	$0x60000001, %eax	/* CD, NW, PE = 1 */
+	movl	%eax, %cr0
+
+	movl	$ap_start_jmp, %eax
+	subl	$ap_start16, %eax
+	movw	%ax, %bp
+
+	/* Jump to ap_start within U-Boot */
+o32 cs	ljmp	*(%bp)
+
+	.align	4
+.globl sipi_params_16bit
+sipi_params_16bit:
+	/* 48-bit far pointer */
+ap_start_jmp:
+	.long	0		/* offset set to ap_start by U-Boot */
+	.word	CODE_SEG	/* segment */
+
+	.word	0		/* padding */
+gdtaddr:
+	.word	0 /* limit */
+	.long	0 /* table */
+	.word	0 /* unused */
+
+.globl ap_start16_code_end
+ap_start16_code_end:
+
+/*
+ * Set up the special 'fs' segment for global_data. Then jump to ap_continue
+ * to set up the AP.
+ */
+.globl ap_start
+ap_start:
+	.code32
+	movw	$DATA_SEG, %ax
+	movw	%ax, %ds
+	movw	%ax, %es
+	movw	%ax, %ss
+	movw	%ax, %gs
+
+	movw	$(X86_GDT_ENTRY_32BIT_FS * X86_GDT_ENTRY_SIZE), %ax
+	movw	%ax, %fs
+
+	/* Load the Interrupt descriptor table */
+	mov	idt_ptr, %ebx
+	lidt	(%ebx)
+
+	/* Obtain cpu number */
+	movl	ap_count, %eax
+1:
+	movl	%eax, %ecx
+	inc	%ecx
+	lock cmpxchg %ecx, ap_count
+	jnz	1b
+
+	/* Setup stacks for each CPU */
+	movl	stack_size, %eax
+	mul	%ecx
+	movl	stack_top, %edx
+	subl	%eax, %edx
+	mov	%edx, %esp
+	/* Save cpu number */
+	mov	%ecx, %esi
+
+	/* Determine if one should check microcode versions */
+	mov	microcode_ptr, %edi
+	test	%edi, %edi
+	jz	microcode_done /* Bypass if no microde exists */
+
+	/* Get the Microcode version */
+	mov	$1, %eax
+	cpuid
+	mov	$MSR_IA32_UCODE_REV, %ecx
+	rdmsr
+	/* If something already loaded skip loading again */
+	test	%edx, %edx
+	jnz	microcode_done
+
+	/* Determine if parallel microcode loading is allowed */
+	cmp	$0xffffffff, microcode_lock
+	je	load_microcode
+
+	/* Protect microcode loading */
+lock_microcode:
+	lock bts $0, microcode_lock
+	jc	lock_microcode
+
+load_microcode:
+	/* Load new microcode */
+	mov	$MSR_IA32_UCODE_WRITE, %ecx
+	xor	%edx, %edx
+	mov	%edi, %eax
+	/*
+	 * The microcode pointer is passed in pointing to the header. Adjust
+	 * pointer to reflect the payload (header size is 48 bytes)
+	 */
+	add	$48, %eax
+	pusha
+	wrmsr
+	popa
+
+	/* Unconditionally unlock microcode loading */
+	cmp	$0xffffffff, microcode_lock
+	je	microcode_done
+
+	xor	%eax, %eax
+	mov	%eax, microcode_lock
+
+microcode_done:
+	/*
+	 * Load MSRs. Each entry in the table consists of:
+	 * 0: index,
+	 * 4: value[31:0]
+	 * 8: value[63:32]
+	 * See struct saved_msr in mp_init.c.
+	 */
+	mov	msr_table_ptr, %edi
+	mov	msr_count, %ebx
+	test	%ebx, %ebx
+	jz	1f
+load_msr:
+	mov	(%edi), %ecx
+	mov	4(%edi), %eax
+	mov	8(%edi), %edx
+	wrmsr
+	add	$12, %edi
+	dec	%ebx
+	jnz	load_msr
+
+1:
+	/* Enable caching */
+	mov	%cr0, %eax
+	and	$0x9fffffff, %eax /* CD, NW = 0 */
+	mov	%eax, %cr0
+
+	/* c_handler(cpu_num) */
+	push	%esi	/* cpu_num */
+	mov	c_handler, %eax
+	call	*%eax
+
+	.align	4
+.globl	sipi_params
+sipi_params:
+idt_ptr:
+	.long 0
+stack_top:
+	.long 0
+stack_size:
+	.long 0
+microcode_lock:
+	.long 0
+microcode_ptr:
+	.long 0
+msr_table_ptr:
+	.long 0
+msr_count:
+	.long 0
+c_handler:
+	.long 0
+ap_count:
+	.long 0
diff --git a/arch/x86/include/asm/mp.h b/arch/x86/include/asm/mp.h
new file mode 100644
index 0000000..3abc692
--- /dev/null
+++ b/arch/x86/include/asm/mp.h
@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ *
+ * SPDX-License-Identifier:	GPL-2.0
+ *
+ * Taken from coreboot file of the same name
+ */
+
+#ifndef _X86_MP_H_
+#define _X86_MP_H_
+
+#include <asm/atomic.h>
+
+typedef int (*mp_callback_t)(struct udevice *cpu, void *arg);
+
+/*
+ * A mp_flight_record details a sequence of calls for the APs to perform
+ * along with the BSP to coordinate sequencing. Each flight record either
+ * provides a barrier for each AP before calling the callback or the APs
+ * are allowed to perform the callback without waiting. Regardless, each
+ * record has the cpus_entered field incremented for each record. When
+ * the BSP observes that the cpus_entered matches the number of APs
+ * the bsp_call is called with bsp_arg and upon returning releases the
+ * barrier allowing the APs to make further progress.
+ *
+ * Note that ap_call() and bsp_call() can be NULL. In the NULL case the
+ * callback will just not be called.
+ */
+struct mp_flight_record {
+	atomic_t barrier;
+	atomic_t cpus_entered;
+	mp_callback_t ap_call;
+	void *ap_arg;
+	mp_callback_t bsp_call;
+	void *bsp_arg;
+} __attribute__((aligned(ARCH_DMA_MINALIGN)));
+
+#define _MP_FLIGHT_RECORD(barrier_, ap_func_, ap_arg_, bsp_func_, bsp_arg_) \
+	{							\
+		.barrier = ATOMIC_INIT(barrier_),		\
+		.cpus_entered = ATOMIC_INIT(0),			\
+		.ap_call = ap_func_,				\
+		.ap_arg = ap_arg_,				\
+		.bsp_call = bsp_func_,				\
+		.bsp_arg = bsp_arg_,				\
+	}
+
+#define MP_FR_BLOCK_APS(ap_func_, ap_arg_, bsp_func_, bsp_arg_) \
+	_MP_FLIGHT_RECORD(0, ap_func_, ap_arg_, bsp_func_, bsp_arg_)
+
+#define MP_FR_NOBLOCK_APS(ap_func_, ap_arg_, bsp_func_, bsp_arg_) \
+	_MP_FLIGHT_RECORD(1, ap_func_, ap_arg_, bsp_func_, bsp_arg_)
+
+/*
+ * The mp_params structure provides the arguments to the mp subsystem
+ * for bringing up APs.
+ *
+ * At present this is overkill for U-Boot, but it may make it easier to add
+ * SMM support.
+ */
+struct mp_params {
+	int num_cpus; /* Total cpus include BSP */
+	int parallel_microcode_load;
+	const void *microcode_pointer;
+	/* Flight plan  for APs and BSP */
+	struct mp_flight_record *flight_plan;
+	int num_records;
+};
+
+/*
+ * mp_init() will set up the SIPI vector and bring up the APs according to
+ * mp_params. Each flight record will be executed according to the plan. Note
+ * that the MP infrastructure uses SMM default area without saving it. It's
+ * up to the chipset or mainboard to either e820 reserve this area or save this
+ * region prior to calling mp_init() and restoring it after mp_init returns.
+ *
+ * At the time mp_init() is called the MTRR MSRs are mirrored into APs then
+ * caching is enabled before running the flight plan.
+ *
+ * The MP init has the following properties:
+ * 1. APs are brought up in parallel.
+ * 2. The ordering of the cpu number and APIC ids is not deterministic.
+ *    Therefore, one cannot rely on this property or the order of devices in
+ *    the device tree unless the chipset or mainboard knows the APIC ids
+ *    a priori.
+ *
+ * mp_init() returns < 0 on error, 0 on success.
+ */
+int mp_init(struct mp_params *params);
+
+/* Probes the CPU device */
+int mp_init_cpu(struct udevice *cpu, void *unused);
+
+#endif /* _X86_MP_H_ */
diff --git a/arch/x86/include/asm/sipi.h b/arch/x86/include/asm/sipi.h
new file mode 100644
index 0000000..bb2f0de
--- /dev/null
+++ b/arch/x86/include/asm/sipi.h
@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2015 Gooogle, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _ASM_SIPI_H
+#define _ASM_SIPI_H
+
+/**
+ * struct sipi_params_16bit - 16-bit SIPI entry-point parameters
+ *
+ * These are set up in the same space as the SIPI 16-bit code so that each AP
+ * can access the parameters when it boots.
+ *
+ * Each of these must be set up for the AP to boot, except @segment which is
+ * set in the assembly code.
+ *
+ * @ap_start:		32-bit SIPI entry point for U-Boot
+ * @segment:		Code segment for U-Boot
+ * @pad:		Padding (not used)
+ * @gdt_limit:		U-Boot GDT limit (X86_GDT_SIZE - 1)
+ * @gdt:		U-Boot GDT (gd->arch.gdt)
+ * @unused:		Not used
+ */
+struct __packed sipi_params_16bit {
+	u32 ap_start;
+	u16 segment;
+	u16 pad;
+
+	u16 gdt_limit;
+	u32 gdt;
+	u16 unused;
+};
+
+/**
+ * struct sipi_params - 32-bit SIP entry-point parameters
+ *
+ * These are used by the AP init code and must be set up before the APs start.
+ *
+ * The stack area extends down from @stack_top, with @stack_size allocated
+ * for each AP.
+ *
+ * @idt_ptr:		Interrupt descriptor table pointer
+ * @stack_top:		Top of the AP stack area
+ * @stack_size:		Size of each AP's stack
+ * @microcode_lock:	Used to ensure only one AP loads microcode at once
+ * @microcode_ptr:	Pointer to microcode, or 0 if none
+ * @msr_table_ptr:	Pointer to saved MSRs, a list of struct saved_msr
+ * @msr_count:		Number of saved MSRs
+ * @c_handler:		C function to call once early init is complete
+ * @ap_count:		Shared atomic value to allocate CPU indexes
+ */
+struct sipi_params {
+	u32 idt_ptr;
+	u32 stack_top;
+	u32 stack_size;
+	u32 microcode_lock;
+	u32 microcode_ptr;
+	u32 msr_table_ptr;
+	u32 msr_count;
+	u32 c_handler;
+	atomic_t ap_count;
+};
+
+/* 16-bit AP entry point */
+void ap_start16(void);
+
+/* end of 16-bit code/data, marks the region to be copied to SIP vector */
+void ap_start16_code_end(void);
+
+/* 32-bit AP entry point */
+void ap_start(void);
+
+extern char sipi_params_16bit[];
+extern char sipi_params[];
+
+#endif
diff --git a/arch/x86/include/asm/smm.h b/arch/x86/include/asm/smm.h
new file mode 100644
index 0000000..79b4a8e
--- /dev/null
+++ b/arch/x86/include/asm/smm.h
@@ -0,0 +1,14 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ * Copyright (C) 2008-2009 coresystems GmbH
+ *
+ * SPDX-License-Identifier:	GPL-2.0
+ */
+
+#ifndef CPU_X86_SMM_H
+#define CPU_X86_SMM_H
+
+#define SMM_DEFAULT_BASE 0x30000
+#define SMM_DEFAULT_SIZE 0x10000
+
+#endif
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 16/20] x86: Add functions to set and clear bits on MSRs

[Simon Glass]

Since we do these sorts of operations a lot, it is useful to have a simpler
API, similar to clrsetbits_le32().

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 arch/x86/include/asm/msr.h | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h
index 1955a75..5349519 100644
--- a/arch/x86/include/asm/msr.h
+++ b/arch/x86/include/asm/msr.h
@@ -128,6 +128,25 @@ static inline void wrmsr(unsigned msr, unsigned low, unsigned high)
 #define wrmsrl(msr, val)						\
 	native_write_msr((msr), (u32)((u64)(val)), (u32)((u64)(val) >> 32))
 
+static inline void msr_clrsetbits_64(unsigned msr, u64 clear, u64 set)
+{
+	u64 val;
+
+	val = native_read_msr(msr);
+	val &= ~clear;
+	val |= set;
+	wrmsrl(msr, val);
+}
+
+static inline void msr_setbits_64(unsigned msr, u64 set)
+{
+	u64 val;
+
+	val = native_read_msr(msr);
+	val |= set;
+	wrmsrl(msr, val);
+}
+
 /* rdmsr with exception handling */
 #define rdmsr_safe(msr, p1, p2)					\
 ({								\
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 17/20] x86: Allow CPUs to be set up after relocation

[Simon Glass]

This permits init of additional CPU cores after relocation and when driver
model is ready.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 arch/x86/cpu/cpu.c                | 37 +++++++++++++++++++++++++++++++++++++
 arch/x86/include/asm/cpu.h        | 14 ++++++++++++++
 arch/x86/include/asm/u-boot-x86.h |  2 ++
 common/board_r.c                  |  2 +-
 4 files changed, 54 insertions(+), 1 deletion(-)

diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c
index 74bfed2..0d199d7 100644
--- a/arch/x86/cpu/cpu.c
+++ b/arch/x86/cpu/cpu.c
@@ -21,6 +21,8 @@
 
 #include <common.h>
 #include <command.h>
+#include <cpu.h>
+#include <dm.h>
 #include <errno.h>
 #include <malloc.h>
 #include <asm/control_regs.h>
@@ -518,6 +520,15 @@ char *cpu_get_name(char *name)
 	return ptr;
 }
 
+int x86_cpu_get_desc(struct udevice *dev, char *buf, int size)
+{
+	if (size < CPU_MAX_NAME_LEN)
+		return -ENOSPC;
+	cpu_get_name(buf);
+
+	return 0;
+}
+
 int default_print_cpuinfo(void)
 {
 	printf("CPU: %s, vendor %s, device %xh\n",
@@ -600,3 +611,29 @@ int last_stage_init(void)
 	return 0;
 }
 #endif
+
+__weak int x86_init_cpus(void)
+{
+	return 0;
+}
+
+int cpu_init_r(void)
+{
+	return x86_init_cpus();
+}
+
+static const struct cpu_ops cpu_x86_ops = {
+	.get_desc	= x86_cpu_get_desc,
+};
+
+static const struct udevice_id cpu_x86_ids[] = {
+	{ .compatible = "cpu-x86" },
+	{ }
+};
+
+U_BOOT_DRIVER(cpu_x86_drv) = {
+	.name		= "cpu_x86",
+	.id		= UCLASS_CPU,
+	.of_match	= cpu_x86_ids,
+	.ops		= &cpu_x86_ops,
+};
diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
index 37aa6b9..bb34cfb 100644
--- a/arch/x86/include/asm/cpu.h
+++ b/arch/x86/include/asm/cpu.h
@@ -197,6 +197,20 @@ const char *cpu_vendor_name(int vendor);
 char *cpu_get_name(char *name);
 
 /**
+ *
+* x86_cpu_get_desc() - Get a description string for an x86 CPU
+*
+* This uses cpu_get_name() and is suitable to use as the get_desc() method for
+* the I2C uclass.
+*
+* @dev:		Device to check (UCLASS_CPU)
+* @buf:		Buffer to place string
+* @size:	Size of string space
+* @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
+*/
+int x86_cpu_get_desc(struct udevice *dev, char *buf, int size);
+
+/**
  * cpu_call64() - Jump to a 64-bit Linux kernel (internal function)
  *
  * The kernel is uncompressed and the 64-bit entry point is expected to be
diff --git a/arch/x86/include/asm/u-boot-x86.h b/arch/x86/include/asm/u-boot-x86.h
index 122e054..be103c0 100644
--- a/arch/x86/include/asm/u-boot-x86.h
+++ b/arch/x86/include/asm/u-boot-x86.h
@@ -69,6 +69,8 @@ uint64_t timer_get_tsc(void);
 
 void quick_ram_check(void);
 
+int x86_init_cpus(void);
+
 #define PCI_VGA_RAM_IMAGE_START		0xc0000
 
 #endif	/* _U_BOOT_I386_H_ */
diff --git a/common/board_r.c b/common/board_r.c
index 42ff18c..055174d 100644
--- a/common/board_r.c
+++ b/common/board_r.c
@@ -773,7 +773,7 @@ init_fnc_t init_sequence_r[] = {
 	initr_flash,
 #endif
 	INIT_FUNC_WATCHDOG_RESET
-#if defined(CONFIG_PPC) || defined(CONFIG_M68K)
+#if defined(CONFIG_PPC) || defined(CONFIG_M68K) || defined(CONFIG_X86)
 	/* initialize higher level parts of CPU like time base and timers */
 	cpu_init_r,
 #endif
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 18/20] x86: Add a CPU driver for baytrail

[Simon Glass]

This driver supports multi-core init and sets up the CPU frequencies
correctly.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 arch/x86/cpu/baytrail/Makefile           |   1 +
 arch/x86/cpu/baytrail/cpu.c              | 206 +++++++++++++++++++++++++++++++
 arch/x86/include/asm/arch-baytrail/msr.h |  30 +++++
 3 files changed, 237 insertions(+)
 create mode 100644 arch/x86/cpu/baytrail/cpu.c
 create mode 100644 arch/x86/include/asm/arch-baytrail/msr.h

diff --git a/arch/x86/cpu/baytrail/Makefile b/arch/x86/cpu/baytrail/Makefile
index 8914e8b..c78b644 100644
--- a/arch/x86/cpu/baytrail/Makefile
+++ b/arch/x86/cpu/baytrail/Makefile
@@ -4,6 +4,7 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
+obj-y += cpu.o
 obj-y += early_uart.o
 obj-y += fsp_configs.o
 obj-y += pci.o
diff --git a/arch/x86/cpu/baytrail/cpu.c b/arch/x86/cpu/baytrail/cpu.c
new file mode 100644
index 0000000..5a2a8ee
--- /dev/null
+++ b/arch/x86/cpu/baytrail/cpu.c
@@ -0,0 +1,206 @@
+/*
+ * Copyright (C) 2015 Google, Inc
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ *
+ * Based on code from coreboot
+ */
+
+#include <common.h>
+#include <cpu.h>
+#include <dm.h>
+#include <asm/cpu.h>
+#include <asm/lapic.h>
+#include <asm/mp.h>
+#include <asm/msr.h>
+#include <asm/turbo.h>
+#include <asm/arch/msr.h>
+
+#ifdef CONFIG_SMP
+static int enable_smis(struct udevice *cpu, void *unused)
+{
+	return 0;
+}
+
+static struct mp_flight_record mp_steps[] = {
+	MP_FR_BLOCK_APS(mp_init_cpu, NULL, mp_init_cpu, NULL),
+	/* Wait for APs to finish initialization before proceeding. */
+	MP_FR_BLOCK_APS(NULL, NULL, enable_smis, NULL),
+};
+
+static int detect_num_cpus(void)
+{
+	int ecx = 0;
+
+	/*
+	 * Use the algorithm described in Intel 64 and IA-32 Architectures
+	 * Software Developer's Manual Volume 3 (3A, 3B & 3C): System
+	 * Programming Guide, Jan-2015. Section 8.9.2: Hierarchical Mapping
+	 * of CPUID Extended Topology Leaf.
+	 */
+	while (1) {
+		struct cpuid_result leaf_b;
+
+		leaf_b = cpuid_ext(0xb, ecx);
+
+		/*
+		 * Bay Trail doesn't have hyperthreading so just determine the
+		 * number of cores by from level type (ecx[15:8] == * 2)
+		 */
+		if ((leaf_b.ecx & 0xff00) == 0x0200)
+			return leaf_b.ebx & 0xffff;
+		ecx++;
+	}
+}
+
+static int baytrail_init_cpus(void)
+{
+	struct mp_params mp_params;
+
+	lapic_setup();
+
+	mp_params.num_cpus = detect_num_cpus();
+	mp_params.parallel_microcode_load = 0,
+	mp_params.flight_plan = &mp_steps[0];
+	mp_params.num_records = ARRAY_SIZE(mp_steps);
+	mp_params.microcode_pointer = 0;
+
+	if (mp_init(&mp_params)) {
+		printf("Warning: MP init failure\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+#endif
+
+int x86_init_cpus(void)
+{
+#ifdef CONFIG_SMP
+	debug("Init additional CPUs\n");
+	baytrail_init_cpus();
+#endif
+
+	return 0;
+}
+
+void set_max_freq(void)
+{
+	msr_t perf_ctl;
+	msr_t msr;
+
+	/* Enable speed step */
+	msr = msr_read(MSR_IA32_MISC_ENABLES);
+	msr.lo |= (1 << 16);
+	msr_write(MSR_IA32_MISC_ENABLES, msr);
+
+	/*
+	 * Set guaranteed ratio [21:16] from IACORE_RATIOS to bits [15:8] of
+	 * the PERF_CTL
+	 */
+	msr = msr_read(MSR_IACORE_RATIOS);
+	perf_ctl.lo = (msr.lo & 0x3f0000) >> 8;
+
+	/*
+	 * Set guaranteed vid [21:16] from IACORE_VIDS to bits [7:0] of
+	 * the PERF_CTL
+	 */
+	msr = msr_read(MSR_IACORE_VIDS);
+	perf_ctl.lo |= (msr.lo & 0x7f0000) >> 16;
+	perf_ctl.hi = 0;
+
+	msr_write(MSR_IA32_PERF_CTL, perf_ctl);
+}
+
+static int cpu_x86_baytrail_probe(struct udevice *dev)
+{
+	debug("Init baytrail core\n");
+
+	/*
+	 * On bay trail the turbo disable bit is actually scoped at the
+	 * building-block level, not package. For non-BSP cores that are
+	 * within a building block, enable turbo. The cores within the BSP's
+	 * building block will just see it already enabled and move on.
+	 */
+	if (lapicid())
+		turbo_enable();
+
+	/* Dynamic L2 shrink enable and threshold */
+	msr_clrsetbits_64(MSR_PMG_CST_CONFIG_CONTROL, 0x3f000f, 0xe0008),
+
+	/* Disable C1E */
+	msr_clrsetbits_64(MSR_POWER_CTL, 2, 0);
+	msr_setbits_64(MSR_POWER_MISC, 0x44);
+
+	/* Set this core to max frequency ratio */
+	set_max_freq();
+
+	return 0;
+}
+
+static unsigned bus_freq(void)
+{
+	msr_t clk_info = msr_read(MSR_BSEL_CR_OVERCLOCK_CONTROL);
+	switch (clk_info.lo & 0x3) {
+	case 0:
+		return 83333333;
+	case 1:
+		return 100000000;
+	case 2:
+		return 133333333;
+	case 3:
+		return 116666666;
+	default:
+		return 0;
+	}
+}
+
+static unsigned long tsc_freq(void)
+{
+	msr_t platform_info;
+	ulong bclk = bus_freq();
+
+	if (!bclk)
+		return 0;
+
+	platform_info = msr_read(MSR_PLATFORM_INFO);
+
+	return bclk * ((platform_info.lo >> 8) & 0xff);
+}
+
+static int baytrail_get_info(struct udevice *dev, struct cpu_info *info)
+{
+	info->cpu_freq = tsc_freq();
+	info->features = 1 << CPU_FEAT_L1_CACHE | 1 << CPU_FEAT_MMU;
+
+	return 0;
+}
+
+static int cpu_x86_baytrail_bind(struct udevice *dev)
+{
+	struct cpu_platdata *plat = dev_get_parent_platdata(dev);
+
+	plat->cpu_id = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+				      "intel,apic-id", -1);
+
+	return 0;
+}
+
+static const struct cpu_ops cpu_x86_baytrail_ops = {
+	.get_desc	= x86_cpu_get_desc,
+	.get_info	= baytrail_get_info,
+};
+
+static const struct udevice_id cpu_x86_baytrail_ids[] = {
+	{ .compatible = "intel,baytrail-cpu" },
+	{ }
+};
+
+U_BOOT_DRIVER(cpu_x86_baytrail_drv) = {
+	.name		= "cpu_x86_baytrail",
+	.id		= UCLASS_CPU,
+	.of_match	= cpu_x86_baytrail_ids,
+	.bind		= cpu_x86_baytrail_bind,
+	.probe		= cpu_x86_baytrail_probe,
+	.ops		= &cpu_x86_baytrail_ops,
+};
diff --git a/arch/x86/include/asm/arch-baytrail/msr.h b/arch/x86/include/asm/arch-baytrail/msr.h
new file mode 100644
index 0000000..1975aec
--- /dev/null
+++ b/arch/x86/include/asm/arch-baytrail/msr.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2015 Google, Inc
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __asm_arch_msr_h
+#define __asm_arch_msr_h
+
+#define MSR_BSEL_CR_OVERCLOCK_CONTROL	0xcd
+#define MSR_PMG_CST_CONFIG_CONTROL	0xe2
+#define SINGLE_PCTL			(1 << 11)
+#define MSR_POWER_MISC			0x120
+#define ENABLE_ULFM_AUTOCM_MASK		(1 << 2)
+#define ENABLE_INDP_AUTOCM_MASK		(1 << 3)
+#define MSR_IA32_MISC_ENABLES		0x1a0
+#define MSR_POWER_CTL			0x1fc
+#define MSR_PKG_POWER_SKU_UNIT		0x606
+#define MSR_IACORE_RATIOS		0x66a
+#define MSR_IACORE_TURBO_RATIOS		0x66c
+#define MSR_IACORE_VIDS			0x66b
+#define MSR_IACORE_TURBO_VIDS		0x66d
+#define MSR_PKG_TURBO_CFG1		0x670
+#define MSR_CPU_TURBO_WKLD_CFG1		0x671
+#define MSR_CPU_TURBO_WKLD_CFG2		0x672
+#define MSR_CPU_THERM_CFG1		0x673
+#define MSR_CPU_THERM_CFG2		0x674
+#define MSR_CPU_THERM_SENS_CFG		0x675
+
+#endif
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 19/20] x86: Tidy up the LAPIC init code

[Simon Glass]

We don't need to support really old x86 CPUs, so drop this code.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 arch/x86/cpu/lapic.c         | 20 ++++++++++++--------
 arch/x86/include/asm/lapic.h |  7 -------
 2 files changed, 12 insertions(+), 15 deletions(-)

diff --git a/arch/x86/cpu/lapic.c b/arch/x86/cpu/lapic.c
index 4690603..0c9c324 100644
--- a/arch/x86/cpu/lapic.c
+++ b/arch/x86/cpu/lapic.c
@@ -15,7 +15,6 @@
 
 void lapic_setup(void)
 {
-#if NEED_LAPIC == 1
 	/* Only Pentium Pro and later have those MSR stuff */
 	debug("Setting up local apic: ");
 
@@ -46,12 +45,17 @@ void lapic_setup(void)
 		(LAPIC_LVT_REMOTE_IRR | LAPIC_SEND_PENDING |
 			LAPIC_DELIVERY_MODE_NMI));
 
-	debug("apic_id: 0x%02lx, ", lapicid());
-#else /* !NEED_LLAPIC */
-	/* Only Pentium Pro and later have those MSR stuff */
-	debug("Disabling local apic: ");
-	disable_lapic();
-#endif /* !NEED_LAPIC */
-	debug("done.\n");
+	debug("apic_id: 0x%02lx\n", lapicid());
 	post_code(POST_LAPIC);
 }
+
+void lapic_enable(void)
+{
+	msr_t msr;
+
+	msr = msr_read(LAPIC_BASE_MSR);
+	msr.hi &= 0xffffff00;
+	msr.lo &= 0x000007ff;
+	msr.lo |= LAPIC_DEFAULT_BASE | LAPIC_BASE_MSR_ENABLE;
+	msr_write(LAPIC_BASE_MSR, msr);
+}
diff --git a/arch/x86/include/asm/lapic.h b/arch/x86/include/asm/lapic.h
index 0a7f443..dff75c5 100644
--- a/arch/x86/include/asm/lapic.h
+++ b/arch/x86/include/asm/lapic.h
@@ -14,13 +14,6 @@
 #include <asm/msr.h>
 #include <asm/processor.h>
 
-/* See if I need to initialize the local apic */
-#if CONFIG_SMP || CONFIG_IOAPIC
-#  define NEED_LAPIC 1
-#else
-#  define NEED_LAPIC 0
-#endif
-
 static inline __attribute__((always_inline))
 		unsigned long lapic_read(unsigned long reg)
 {
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 20/20] x86: Enable multi-core init for Minnowboard MAX

[Simon Glass]

Enable the CPU uclass and Simple Firmware interface for Minnowbaord MAX. This
enables multi-core support in Linux.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

 arch/x86/dts/minnowmax.dts  | 20 ++++++++++++++++++++
 configs/minnowmax_defconfig |  4 ++++
 2 files changed, 24 insertions(+)

diff --git a/arch/x86/dts/minnowmax.dts b/arch/x86/dts/minnowmax.dts
index ecd4a89..1d08e8c 100644
--- a/arch/x86/dts/minnowmax.dts
+++ b/arch/x86/dts/minnowmax.dts
@@ -26,6 +26,26 @@
 		stdout-path = "/serial";
 	};
 
+	cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		cpu at 0 {
+			device_type = "cpu";
+			compatible = "intel,baytrail-cpu";
+			reg = <0>;
+			intel,apic-id = <0>;
+		};
+
+		cpu at 1 {
+			device_type = "cpu";
+			compatible = "intel,baytrail-cpu";
+			reg = <1>;
+			intel,apic-id = <4>;
+		};
+
+	};
+
 	spi {
 		#address-cells = <1>;
 		#size-cells = <0>;
diff --git a/configs/minnowmax_defconfig b/configs/minnowmax_defconfig
index d1add19..6b70de2 100644
--- a/configs/minnowmax_defconfig
+++ b/configs/minnowmax_defconfig
@@ -8,3 +8,7 @@ CONFIG_FRAMEBUFFER_SET_VESA_MODE=y
 CONFIG_FRAMEBUFFER_VESA_MODE_11A=y
 CONFIG_MMCONF_BASE_ADDRESS=0xe0000000
 CONFIG_HAVE_INTEL_ME=y
+CONFIG_SFI=y
+CONFIG_CPU=y
+CONFIG_CMD_CPU=y
+CONFIG_SMP=y
-- 
2.2.0.rc0.207.ga3a616c

[U-Boot] [PATCH 01/20] Fix comment nits in board_f.c

[Bin Meng]

On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
> Try to make it a little clearer.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
>  common/board_f.c | 9 ++++-----
>  1 file changed, 4 insertions(+), 5 deletions(-)
>
> diff --git a/common/board_f.c b/common/board_f.c
> index 322e070..fbbad1b 100644
> --- a/common/board_f.c
> +++ b/common/board_f.c
> @@ -73,7 +73,7 @@ DECLARE_GLOBAL_DATA_PTR;
>  #endif
>
>  /*
> - * sjg: IMO this code should be
> + * TODO(sjg at chromium.org): IMO this code should be
>   * refactored to a single function, something like:
>   *
>   * void led_set_state(enum led_colour_t colour, int on);
> @@ -300,7 +300,7 @@ __weak ulong board_get_usable_ram_top(ulong total_size)
>  {
>  #ifdef CONFIG_SYS_SDRAM_BASE
>         /*
> -        * Detect whether we have so much RAM it goes past the end of our
> +        * Detect whether we have so much RAM that it goes past the end of our
>          * 32-bit address space. If so, clip the usable RAM so it doesn't.
>          */
>         if (gd->ram_top < CONFIG_SYS_SDRAM_BASE)
> @@ -507,7 +507,7 @@ static int reserve_global_data(void)
>  static int reserve_fdt(void)
>  {
>         /*
> -        * If the device tree is sitting immediate above our image then we
> +        * If the device tree is sitting immediately above our image then we
>          * must relocate it. If it is embedded in the data section, then it
>          * will be relocated with other data.
>          */
> @@ -535,7 +535,7 @@ static int reserve_stacks(void)
>         gd->start_addr_sp &= ~0xf;
>
>         /*
> -        * let the architecture specific code tailor gd->start_addr_sp and
> +        * let the architecture-specific code tailor gd->start_addr_sp and
>          * gd->irq_sp
>          */
>         return arch_reserve_stacks();
> @@ -556,7 +556,6 @@ static int setup_board_part1(void)
>         /*
>          * Save local variables to board info struct
>          */
> -
>         bd->bi_memstart = CONFIG_SYS_SDRAM_BASE;        /* start of memory */
>         bd->bi_memsize = gd->ram_size;                  /* size in bytes */
>
> --

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

[U-Boot] [PATCH 03/20] x86: Remove unwanted MMC debugging

[Bin Meng]

On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
> This printf() should not have made it into the code.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
>  arch/x86/cpu/baytrail/valleyview.c | 1 -
>  1 file changed, 1 deletion(-)
>
> diff --git a/arch/x86/cpu/baytrail/valleyview.c b/arch/x86/cpu/baytrail/valleyview.c
> index a3e837d..9915da5 100644
> --- a/arch/x86/cpu/baytrail/valleyview.c
> +++ b/arch/x86/cpu/baytrail/valleyview.c
> @@ -16,7 +16,6 @@ static struct pci_device_id mmc_supported[] = {
>
>  int cpu_mmc_init(bd_t *bis)
>  {
> -       printf("mmc init\n");
>         return pci_mmc_init("ValleyView SDHCI", mmc_supported,
>                             ARRAY_SIZE(mmc_supported));
>  }
> --

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

[U-Boot] [PATCH 04/20] x86: Disable -Werror

[Bin Meng]

On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
> This is annoying during development and serves no useful purpose since
> warnings are clearly displayed now that we are using Kbuild. Remove this
> option.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
>  arch/x86/cpu/config.mk | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/x86/cpu/config.mk b/arch/x86/cpu/config.mk
> index 84aeaf3..4c4d0c7 100644
> --- a/arch/x86/cpu/config.mk
> +++ b/arch/x86/cpu/config.mk
> @@ -7,7 +7,7 @@
>
>  CROSS_COMPILE ?= i386-linux-
>
> -PLATFORM_CPPFLAGS += -D__I386__ -Werror
> +PLATFORM_CPPFLAGS += -D__I386__
>
>  # DO NOT MODIFY THE FOLLOWING UNLESS YOU REALLY KNOW WHAT YOU ARE DOING!
>  LDPPFLAGS += -DRESET_SEG_START=0xffff0000
> --

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

[U-Boot] [PATCH 05/20] Move display_options functions to their own header

[Bin Meng]

Hi Simon,

On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
> Before adding one more function, create a separate header to help reduce
> the size of common.h. Add the missing function comments and tidy up.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

But please see comments below.

>  include/common.h          | 16 +---------------
>  include/display_options.h | 48 +++++++++++++++++++++++++++++++++++++++++++++++
>  lib/display_options.c     | 13 -------------
>  3 files changed, 49 insertions(+), 28 deletions(-)
>  create mode 100644 include/display_options.h
>
> diff --git a/include/common.h b/include/common.h
> index cde3474..d4d704a 100644
> --- a/include/common.h
> +++ b/include/common.h
> @@ -192,22 +192,8 @@ int        cpu_init(void);
>
>  /* */
>  phys_size_t initdram (int);
> -int    display_options (void);
>
> -/**
> - * print_size() - Print a size with a suffic
> - *
> - * print sizes as "xxx KiB", "xxx.y KiB", "xxx MiB", "xxx.y MiB",
> - * xxx GiB, xxx.y GiB, etc as needed; allow for optional trailing string
> - * (like "\n")
> - *
> - * @size:      Size to print
> - * @suffix     String to print after the size
> - */
> -void print_size(uint64_t size, const char *suffix);
> -
> -int print_buffer(ulong addr, const void *data, uint width, uint count,
> -                uint linelen);
> +#include <display_options.h>
>
>  /* common/main.c */
>  void   main_loop       (void);
> diff --git a/include/display_options.h b/include/display_options.h
> new file mode 100644
> index 0000000..c222ea2
> --- /dev/null
> +++ b/include/display_options.h
> @@ -0,0 +1,48 @@
> +/*
> + * Copyright (c) 2015 Google, Inc
> + *
> + * (C) Copyright 2000-2002
> + * Wolfgang Denk, DENX Software Engineering, wd at denx.de.
> + *
> + * SPDX-License-Identifier:    GPL-2.0+
> + */
> +
> +#ifndef __display_options_h
> +#define __display_options_h

I think we need capital letters here for the macro.

> +/**
> + * print_size() - Print a size with a suffix
> + *
> + * print sizes as "xxx KiB", "xxx.y KiB", "xxx MiB", "xxx.y MiB",

print->Print

> + * xxx GiB, xxx.y GiB, etc as needed; allow for optional trailing string
> + * (like "\n")
> + *
> + * @size:      Size to print
> + * @suffix     String to print after the size
> + */
> +void print_size(uint64_t size, const char *suffix);
> +
> +/**
> + * print_buffer() - Print data buffer in hex and ascii form
> + *
> + * Data reads are buffered so that each memory address is only read once.
> + * This is useful when displaying the contents of volatile registers.
> + *
> + * @addr:      Starting address to display at start of line
> + * @data:      pointer to data buffer
> + * @width:     data value width.  May be 1, 2, or 4.
> + * @count:     number of values to display
> + * @linelen:   Number of values to print per line; specify 0 for default length
> + */
> +int print_buffer(ulong addr, const void *data, uint width, uint count,
> +                uint linelen);
> +
> +/**
> + * display_options() - display the version string / build tag
> + *
> + * This displays the U-Boot version string. If a build tag is available this
> + * is displayed also.
> + */
> +int display_options(void);
> +
> +#endif
> diff --git a/lib/display_options.c b/lib/display_options.c
> index d5d17b2..3f32bcd 100644
> --- a/lib/display_options.c
> +++ b/lib/display_options.c
> @@ -63,19 +63,6 @@ void print_size(uint64_t size, const char *s)
>         printf (" %ciB%s", c, s);
>  }
>
> -/*
> - * Print data buffer in hex and ascii form to the terminal.
> - *
> - * data reads are buffered so that each memory address is only read once.
> - * Useful when displaying the contents of volatile registers.
> - *
> - * parameters:
> - *    addr: Starting address to display at start of line
> - *    data: pointer to data buffer
> - *    width: data value width.  May be 1, 2, or 4.
> - *    count: number of values to display
> - *    linelen: Number of values to print per line; specify 0 for default length
> - */
>  #define MAX_LINE_LENGTH_BYTES (64)
>  #define DEFAULT_LINE_LENGTH_BYTES (16)
>  int print_buffer(ulong addr, const void *data, uint width, uint count,
> --

Regards,
Bin

[U-Boot] [PATCH 06/20] Add print_freq() to display frequencies nicely

[Bin Meng]

Hi Simon,

On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
> Add a function similar to print_size() that works for frequencies. It can
> handle from Hz to GHz.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
>  include/display_options.h | 11 +++++++++++
>  lib/display_options.c     | 41 +++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 52 insertions(+)
>
> diff --git a/include/display_options.h b/include/display_options.h
> index c222ea2..10b4641 100644
> --- a/include/display_options.h
> +++ b/include/display_options.h
> @@ -23,6 +23,17 @@
>  void print_size(uint64_t size, const char *suffix);
>
>  /**
> + * print_freq() - Print a frequency with a suffix
> + *
> + * print frequencies as "x.xx GHz", "xxx KHz", etc as needed; allow for

print->Print

> + * optional trailing string (like "\n")
> + *
> + * @freq:      Frequency to print in Hz
> + * @suffix     String to print after the frequency
> + */
> +void print_freq(uint64_t freq, const char *suffix);
> +
> +/**
>   * print_buffer() - Print data buffer in hex and ascii form
>   *
>   * Data reads are buffered so that each memory address is only read once.
> diff --git a/lib/display_options.c b/lib/display_options.c
> index 3f32bcd..cf6f50b 100644
> --- a/lib/display_options.c
> +++ b/lib/display_options.c
> @@ -7,6 +7,7 @@
>
>  #include <config.h>
>  #include <common.h>
> +#include <div64.h>
>  #include <inttypes.h>
>  #include <version.h>
>  #include <linux/ctype.h>
> @@ -22,6 +23,46 @@ int display_options (void)
>         return 0;
>  }
>
> +#ifndef CONFIG_SH
> +/* SH gcc 4.6 toolchain produces "undefined reference to '__umoddi3' here */
> +void print_freq(uint64_t freq, const char *s)
> +{
> +       unsigned long m = 0, n;
> +       uint32_t f;
> +       static const char names[] = {'G', 'M', 'K'};
> +       unsigned long d = 1e9;
> +       char c = 0;
> +       unsigned int i;
> +
> +       for (i = 0; i < ARRAY_SIZE(names); i++, d /= 10) {

I think this is broken. Should be d /= 1000;

> +               if (freq >= d) {
> +                       c = names[i];
> +                       break;
> +               }
> +       }
> +
> +       if (!c) {
> +               printf("%" PRIu64 " Hz%s", freq, s);
> +               return;
> +       }
> +
> +       f = do_div(freq, d);
> +       n = freq;
> +
> +       /* If there's a remainder, show the first few digits */
> +       if (f) {
> +               m = f % 1000;

This is broken too. Should be m = f % d;

> +               while (!(m % 10))

And I think you need add a variable to control how many first few
digits you want to show in this loop.

> +                       m /= 10;
> +       }
> +
> +       printf("%lu", n);
> +       if (m)
> +               printf(".%ld", m);
> +       printf(" %cHz%s", c, s);
> +}
> +#endif
> +
>  void print_size(uint64_t size, const char *s)
>  {
>         unsigned long m = 0, n;
> --

Regards,
Bin

[U-Boot] [PATCH 07/20] x86: Add support for the Simple Firmware Interface (SFI)

[Bin Meng]

Hi Simon,

On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
> This provides a way of passing information to Linux without requiring the
> full ACPI horror. Provide a rudimentary implementation sufficient to be
> recognised and parsed by Linux.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---

It's great to see we are adding more configuration tables support in U-Boot.

>  arch/x86/Kconfig      |  28 +++++++++
>  arch/x86/lib/Makefile |   1 +
>  arch/x86/lib/sfi.c    | 171 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  arch/x86/lib/zimage.c |   7 +++
>  include/linux/sfi.h   | 139 ++++++++++++++++++++++++++++++++++++++++
>  5 files changed, 346 insertions(+)
>  create mode 100644 arch/x86/lib/sfi.c
>  create mode 100644 include/linux/sfi.h
>
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index aaceaef..30a08ec 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -499,6 +499,34 @@ config PCIE_ECAM_BASE
>           assigned to PCI devices - i.e. the memory and prefetch regions, as
>           passed to pci_set_region().
>
> +config SFI

Can we rename this to "GENERATE_SFI_TABLE" under menu "System tables"
in arch/x86/Kconfig? See more comments below.

> +       bool "SFI (Simple Firmware Interface) Support"
> +       ---help---

I think just 'help', like other options.

> +       The Simple Firmware Interface (SFI) provides a lightweight method
> +       for platform firmware to pass information to the operating system
> +       via static tables in memory.  Kernel SFI support is required to
> +       boot on SFI-only platforms.  If you have ACPI tables then these are
> +       used instead.

The indention is wrong for this paragraph.

> +       For more information, see http://simplefirmware.org
> +
> +       Say 'Y' here to enable the kernel to boot properly on SFI-only
> +       platforms.

I guess this is from Linux kernel, so could be removed for U-Boot?

> +config SFI_BASE

We can just drop this config option, and let U-Boot calculate its
address in write_tables(). See more comments below.

> +       hex "SFI base address (0xe0000 to 0xff000)"
> +       default 0xe0000
> +       depends on SFI
> +       help
> +         The OS searches addresses in the range 0xe00000 to 0xffff0 for the
> +         Simple Firmware Interface (SFI) header. Use this option to determine
> +         where the table will be placed. It must be a multiple of 16 bytes and
> +         the header part (which U-Boot places at the end) must not cross a 4KB
> +         boundary. A 4KB-aligned address is recommended for these reasons.
> +
> +         U-Boot writes this table in sfi_write_tables() just before booting
> +         the OS.
> +
>  config BOOTSTAGE
>         default y
>
> diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
> index 0178fe1..c55b9be 100644
> --- a/arch/x86/lib/Makefile
> +++ b/arch/x86/lib/Makefile
> @@ -26,6 +26,7 @@ obj-y += pirq_routing.o
>  obj-y  += relocate.o
>  obj-y += physmem.o
>  obj-$(CONFIG_X86_RAMTEST) += ramtest.o
> +obj-$(CONFIG_SFI) += sfi.o

I think it is safe to say: obj-y += sfi.o

>  obj-y  += string.o
>  obj-y  += tables.o
>  obj-$(CONFIG_SYS_X86_TSC_TIMER)        += tsc_timer.o
> diff --git a/arch/x86/lib/sfi.c b/arch/x86/lib/sfi.c
> new file mode 100644
> index 0000000..060651b
> --- /dev/null
> +++ b/arch/x86/lib/sfi.c
> @@ -0,0 +1,171 @@
> +/*
> + * Copyright (c) 2015 Google, Inc
> + * Written by Simon Glass <sjg@chromium.org>
> + *
> + * SPDX-License-Identifier:    GPL-2.0+
> + */
> +
> +/*
> + * Intel Simple Firmware Interface (SFI)
> + *
> + * Yet another way to pass information to the Linux kernel.
> + *
> + * See https://simplefirmware.org/ for details
> + */
> +
> +#include <common.h>
> +#include <cpu.h>
> +#include <dm.h>
> +#include <asm/cpu.h>
> +#include <asm/ioapic.h>
> +#include <dm/uclass-internal.h>
> +#include <linux/sfi.h>
> +
> +struct table_info {
> +       u32 base;
> +       int ptr;
> +       u32 entry_start;
> +       u64 table[16];

I assume 16 is SFI_TABLE_MAX_ENTRIES?

> +       int count;
> +};
> +
> +void *get_entry_start(struct table_info *tab)

Should this function be static?

> +{
> +       if (tab->count == ARRAY_SIZE(tab->table))

Then we can just write: tab->count == SFI_TABLE_MAX_ENTRIES

> +               return NULL;
> +       tab->entry_start = tab->base + tab->ptr;
> +       tab->table[tab->count] = tab->entry_start;
> +       tab->entry_start += sizeof(struct sfi_table_header);
> +
> +       return (void *)tab->entry_start;
> +}
> +
> +static void finish_table(struct table_info *tab, const char *sig, void *entry)
> +{
> +       struct sfi_table_header *hdr;
> +       uint8_t *p;
> +       int sum;
> +
> +       hdr = (struct sfi_table_header *)(tab->base + tab->ptr);
> +       strcpy(hdr->sig, sig);
> +       hdr->len = sizeof(*hdr) + ((ulong)entry - tab->entry_start);
> +       hdr->rev = 1;
> +       strncpy(hdr->oem_id, "U-Boot", SFI_OEM_ID_SIZE);
> +       strncpy(hdr->oem_table_id, "Table v1", SFI_OEM_TABLE_ID_SIZE);
> +       hdr->csum = 0;
> +       for (sum = 0, p = (uint8_t *)hdr; (void *)p < entry; p++)
> +               sum += *p;
> +       hdr->csum = 256 - (sum & 255);

The above can be replaced to:

hdr->csum = 0;
hdr->csum = table_compute_checksum(hdr, hdr->len);

> +       tab->ptr += hdr->len;
> +       tab->ptr = ALIGN(tab->ptr, 16);
> +       tab->count++;
> +}
> +
> +static int sfi_write_system_header(struct table_info *tab)
> +{
> +       u64 *entry = get_entry_start(tab);
> +       int i;
> +
> +       if (!entry)
> +               return -ENOSPC;

Need a blank line here.

> +       for (i = 0; i < tab->count; i++)
> +               *entry++ = tab->table[i];
> +       finish_table(tab, SFI_SIG_SYST, entry);
> +
> +       return 0;
> +}
> +
> +static int sfi_write_cpus(struct table_info *tab)
> +{
> +       struct sfi_cpu_table_entry *entry = get_entry_start(tab);
> +       struct udevice *dev;
> +       int count = 0;
> +
> +       if (!entry)
> +               return -ENOSPC;

Need a blank line here.

> +       for (uclass_find_first_device(UCLASS_CPU, &dev);

UCLASS_CPU is introduced in #8 of this series. Please reorder the patches.

> +            dev;
> +            uclass_find_next_device(&dev)) {
> +               struct cpu_platdata *plat = dev_get_parent_platdata(dev);
> +
> +               if (!device_active(dev))
> +                       continue;
> +               entry->apic_id = plat->cpu_id;
> +               entry++;
> +               count++;
> +       }
> +
> +       /* Omit the table if there is only one CPU */
> +       if (count > 1)
> +               finish_table(tab, SFI_SIG_CPUS, entry);
> +
> +       return 0;
> +}
> +
> +static int sfi_write_apic(struct table_info *tab)
> +{
> +       struct sfi_apic_table_entry *entry = get_entry_start(tab);
> +
> +       if (!entry)
> +               return -ENOSPC;
> +
> +       entry->phys_addr = IO_APIC_ADDR;
> +       entry++;
> +       finish_table(tab, SFI_SIG_APIC, entry);
> +
> +       return 0;
> +}
> +
> +static int sfi_write_rtc(struct table_info *tab)
> +{
> +       struct sfi_rtc_table_entry *entry = get_entry_start(tab);
> +
> +       if (!entry)
> +               return -ENOSPC;
> +
> +       entry->phys_addr = CONFIG_SYS_ISA_IO_BASE_ADDRESS + 0x70;
> +       entry->irq = 0;         /* Should be 8? */
> +       entry++;
> +       finish_table(tab, SFI_SIG_MRTC, entry);
> +
> +       return 0;
> +}

Is this RTC table a must-have that without it Linux cannot boot? If
not, I think we can leave it unimplemented.

> +static int sfi_write_xsdt(struct table_info *tab)
> +{
> +       struct sfi_xsdt_header *entry = get_entry_start(tab);
> +
> +       if (!entry)
> +               return -ENOSPC;
> +
> +       entry->oem_revision = 1;
> +       entry->creator_id = 1;
> +       entry->creator_revision = 1;
> +       entry++;
> +       finish_table(tab, SFI_SIG_XSDT, entry);
> +
> +       return 0;
> +}
> +
> +int sfi_write_tables(void)
> +{
> +       struct table_info table;
> +
> +       table.base = CONFIG_SFI_BASE;
> +       table.ptr = 0;
> +       table.count = 0;
> +       sfi_write_cpus(&table);
> +       sfi_write_apic(&table);
> +       sfi_write_rtc(&table);
> +
> +       /*
> +        * The SFI specification marks the XSDT table as option, but Linux 4.0
> +        * crashes on start-up when it is not provided.
> +        */
> +       sfi_write_xsdt(&table);
> +
> +       /* Finally, write out the system header which points to the others */
> +       sfi_write_system_header(&table);
> +
> +       return 0;
> +}
> diff --git a/arch/x86/lib/zimage.c b/arch/x86/lib/zimage.c
> index c3f8a73..d2c68f6 100644
> --- a/arch/x86/lib/zimage.c
> +++ b/arch/x86/lib/zimage.c
> @@ -24,6 +24,7 @@
>  #include <asm/arch/timestamp.h>
>  #endif
>  #include <linux/compiler.h>
> +#include <linux/sfi.h>
>
>  DECLARE_GLOBAL_DATA_PTR;
>
> @@ -232,9 +233,15 @@ int setup_zimage(struct boot_params *setup_base, char *cmd_line, int auto_boot,
>  {
>         struct setup_header *hdr = &setup_base->hdr;
>         int bootproto = get_boot_protocol(hdr);
> +       int ret;
>
>         setup_base->e820_entries = install_e820_map(
>                 ARRAY_SIZE(setup_base->e820_map), setup_base->e820_map);
> +       ret = sfi_write_tables();
> +       if (ret && ret != -ENOSYS) {
> +               printf("Failed to write SFI tables: err=%d\n", ret);
> +               return ret;
> +       }

Can we move this to arch/x86/lib/tables.c which is the central place
to write x86 configuration tables? Like this:

void write_tables(void)
{
        u32 __maybe_unused rom_table_end = ROM_TABLE_ADDR;

#ifdef CONFIG_GENERATE_PIRQ_TABLE
        rom_table_end = write_pirq_routing_table(rom_table_end);
        rom_table_end = ALIGN(rom_table_end, 1024);
#endif

#ifdef CONFIG_GENERATE_SFI_TABLE
        rom_table_end = write_sfi_table(rom_table_end);
        rom_table_end = ALIGN(rom_table_end, 1024);
#endif
}

>         if (bootproto == 0x0100) {
>                 setup_base->screen_info.cl_magic = COMMAND_LINE_MAGIC;
> diff --git a/include/linux/sfi.h b/include/linux/sfi.h
> new file mode 100644
> index 0000000..4094fc7
> --- /dev/null
> +++ b/include/linux/sfi.h

I believe it is better to put this file to arch/x86/include/asm/ as
this is x86-specific tables (like the apic stuff).

> @@ -0,0 +1,139 @@
> +/*
> + * Copyright(c) 2009 Intel Corporation. All rights reserved.
> + *
> + * SPDX-License-Identifier:    GPL-2.0+        BSD-3-Clause
> + */
> +
> +#ifndef _LINUX_SFI_H
> +#define _LINUX_SFI_H
> +
> +#include <errno.h>
> +#include <linux/types.h>
> +
> +/* Table signatures reserved by the SFI specification */
> +#define SFI_SIG_SYST           "SYST"
> +#define SFI_SIG_FREQ           "FREQ"
> +#define SFI_SIG_IDLE           "IDLE"

The SFI spec v0.8.2 deleted the "IDEL" table.

> +#define SFI_SIG_CPUS           "CPUS"
> +#define SFI_SIG_MTMR           "MTMR"
> +#define SFI_SIG_MRTC           "MRTC"
> +#define SFI_SIG_MMAP           "MMAP"
> +#define SFI_SIG_APIC           "APIC"
> +#define SFI_SIG_XSDT           "XSDT"
> +#define SFI_SIG_WAKE           "WAKE"
> +#define SFI_SIG_DEVS           "DEVS"
> +#define SFI_SIG_GPIO           "GPIO"
> +
> +#define SFI_SIGNATURE_SIZE     4
> +#define SFI_OEM_ID_SIZE                6
> +#define SFI_OEM_TABLE_ID_SIZE  8
> +
> +#define SFI_NAME_LEN           16
> +
> +#define SFI_SYST_SEARCH_BEGIN          0x000e0000
> +#define SFI_SYST_SEARCH_END            0x000fffff

I think we can remove these two macros.

> +#define SFI_GET_NUM_ENTRIES(ptable, entry_type) \
> +       ((ptable->header.len - sizeof(struct sfi_table_header)) / \
> +       (sizeof(entry_type)))
> +
> +/* Table structures must be byte-packed to match the SFI specification */
> +struct sfi_table_header {
> +       char    sig[SFI_SIGNATURE_SIZE];
> +       u32     len;
> +       u8      rev;
> +       u8      csum;
> +       char    oem_id[SFI_OEM_ID_SIZE];
> +       char    oem_table_id[SFI_OEM_TABLE_ID_SIZE];
> +} __packed;

IIRC, the checkpatch.pl will complain if __packed is put after the
structure defines. If that's true, please fix it globally.

> +struct sfi_table_simple {
> +       struct sfi_table_header         header;
> +       u64                             pentry[1];
> +} __packed;
> +
> +/* Comply with UEFI spec 2.1 */
> +struct sfi_mem_entry {
> +       u32     type;
> +       u64     phys_start;
> +       u64     virt_start;
> +       u64     pages;
> +       u64     attrib;
> +} __packed;
> +
> +struct sfi_cpu_table_entry {
> +       u32     apic_id;
> +} __packed;
> +
> +struct sfi_cstate_table_entry {
> +       u32     hint;           /* MWAIT hint */
> +       u32     latency;        /* latency in ms */
> +} __packed;
> +
> +struct sfi_apic_table_entry {
> +       u64     phys_addr;      /* phy base addr for APIC reg */
> +} __packed;
> +
> +struct sfi_freq_table_entry {
> +       u32     freq_mhz;       /* in MHZ */
> +       u32     latency;        /* transition latency in ms */
> +       u32     ctrl_val;       /* value to write to PERF_CTL */
> +} __packed;
> +
> +struct sfi_wake_table_entry {
> +       u64     phys_addr;      /* pointer to where the wake vector locates */
> +} __packed;
> +
> +struct sfi_timer_table_entry {
> +       u64     phys_addr;      /* phy base addr for the timer */
> +       u32     freq_hz;        /* in HZ */
> +       u32     irq;
> +} __packed;
> +
> +struct sfi_rtc_table_entry {
> +       u64     phys_addr;      /* phy base addr for the RTC */
> +       u32     irq;
> +} __packed;
> +
> +struct sfi_device_table_entry {
> +       u8      type;           /* bus type, I2C, SPI or ...*/
> +#define SFI_DEV_TYPE_SPI       0
> +#define SFI_DEV_TYPE_I2C       1
> +#define SFI_DEV_TYPE_UART      2
> +#define SFI_DEV_TYPE_HSI       3
> +#define SFI_DEV_TYPE_IPC       4

There is one more type added in SFI spec v0.8.2 which is SD. And
please move these defines out of the structure.

> +       u8      host_num;       /* attached to host 0, 1...*/
> +       u16     addr;
> +       u8      irq;
> +       u32     max_freq;
> +       char    name[SFI_NAME_LEN];
> +} __packed;
> +
> +struct sfi_gpio_table_entry {
> +       char    controller_name[SFI_NAME_LEN];
> +       u16     pin_no;
> +       char    pin_name[SFI_NAME_LEN];
> +} __packed;
> +
> +struct sfi_xsdt_header {
> +       uint32_t oem_revision;
> +       uint32_t creator_id;
> +       uint32_t creator_revision;
> +};
> +
> +typedef int (*sfi_table_handler) (struct sfi_table_header *table);
> +
> +#ifdef CONFIG_SFI

There is no need to wrap this with #ifdefs.

> +/**
> + * sfi_write_tables() - Write Simple Firmware Interface tables
> + */
> +int sfi_write_tables(void);
> +
> +#else
> +
> +static inline int sfi_write_tables(void) { return -ENOSYS; }
> +
> +#endif
> +
> +#endif /*_LINUX_SFI_H */
> --

Regards,
Bin

[U-Boot] [PATCH 08/20] dm: Implement a CPU uclass

[Bin Meng]

Hi Simon,

On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
> It is useful to be able to keep track of the available CPUs in a multi-CPU
> system. This uclass is mostly intended for use with SMP systems.
>
> The uclass provides methods for getting basic information about each CPU.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
>  drivers/Kconfig          |  2 ++
>  drivers/Makefile         |  1 +
>  drivers/cpu/Kconfig      |  8 +++++
>  drivers/cpu/Makefile     |  7 ++++
>  drivers/cpu/cpu-uclass.c | 61 +++++++++++++++++++++++++++++++++++
>  include/cpu.h            | 84 ++++++++++++++++++++++++++++++++++++++++++++++++
>  include/dm/uclass-id.h   |  1 +
>  7 files changed, 164 insertions(+)
>  create mode 100644 drivers/cpu/Kconfig
>  create mode 100644 drivers/cpu/Makefile
>  create mode 100644 drivers/cpu/cpu-uclass.c
>  create mode 100644 include/cpu.h
>
> diff --git a/drivers/Kconfig b/drivers/Kconfig
> index 941aa0c..1f40887 100644
> --- a/drivers/Kconfig
> +++ b/drivers/Kconfig
> @@ -2,6 +2,8 @@ menu "Device Drivers"
>
>  source "drivers/core/Kconfig"
>
> +source "drivers/cpu/Kconfig"
> +
>  source "drivers/demo/Kconfig"
>
>  source "drivers/pci/Kconfig"
> diff --git a/drivers/Makefile b/drivers/Makefile
> index 5ef58c0..405b64b 100644
> --- a/drivers/Makefile
> +++ b/drivers/Makefile
> @@ -3,6 +3,7 @@ obj-$(CONFIG_DM_DEMO) += demo/
>  obj-$(CONFIG_BIOSEMU) += bios_emulator/
>  obj-y += block/
>  obj-$(CONFIG_BOOTCOUNT_LIMIT) += bootcount/
> +obj-$(CONFIG_CPU) += cpu/

Should it be CONFIG_DM_CPU?

>  obj-y += crypto/
>  obj-$(CONFIG_FPGA) += fpga/
>  obj-y += hwmon/
> diff --git a/drivers/cpu/Kconfig b/drivers/cpu/Kconfig
> new file mode 100644
> index 0000000..23745e3
> --- /dev/null
> +++ b/drivers/cpu/Kconfig
> @@ -0,0 +1,8 @@
> +config CPU
> +       bool "Enable CPU drivers using Driver Model"
> +       help
> +         This allows drivers to be provided for CPUs and their type to be
> +         specified in the board's device tree. For boards which support
> +         multiple CPUs, they normally have to be set up in U-Boot so that
> +         they can work correctly in the OS. This provides a framework for
> +         finding out information about available CPUs and making changes.
> diff --git a/drivers/cpu/Makefile b/drivers/cpu/Makefile
> new file mode 100644
> index 0000000..8710160
> --- /dev/null
> +++ b/drivers/cpu/Makefile
> @@ -0,0 +1,7 @@
> +#
> +# Copyright (c) 2015 Google, Inc
> +# Wolfgang Denk, DENX Software Engineering, wd at denx.de.
> +#
> +# SPDX-License-Identifier:      GPL-2.0+
> +#
> +obj-$(CONFIG_CPU) += cpu-uclass.o
> diff --git a/drivers/cpu/cpu-uclass.c b/drivers/cpu/cpu-uclass.c
> new file mode 100644
> index 0000000..ab18ee2
> --- /dev/null
> +++ b/drivers/cpu/cpu-uclass.c
> @@ -0,0 +1,61 @@
> +/*
> + * Copyright (C) 2015 Google, Inc
> + * Written by Simon Glass <sjg@chromium.org>
> + *
> + * SPDX-License-Identifier:    GPL-2.0+
> + */
> +
> +#include <common.h>
> +#include <cpu.h>
> +#include <dm.h>
> +#include <dm/lists.h>
> +#include <dm/root.h>
> +
> +int cpu_get_desc(struct udevice *dev, char *buf, int size)
> +{
> +       struct cpu_ops *ops = cpu_get_ops(dev);
> +
> +       if (!ops->get_desc)
> +               return -ENOSYS;
> +
> +       return ops->get_desc(dev, buf, size);
> +}
> +
> +int cpu_get_info(struct udevice *dev, struct cpu_info *info)
> +{
> +       struct cpu_ops *ops = cpu_get_ops(dev);
> +
> +       if (!ops->get_desc)
> +               return -ENOSYS;
> +
> +       return ops->get_info(dev, info);
> +}
> +
> +U_BOOT_DRIVER(cpu_bus) = {
> +       .name   = "cpu_bus",
> +       .id     = UCLASS_SIMPLE_BUS,
> +       .per_child_platdata_auto_alloc_size = sizeof(struct cpu_platdata),
> +};
> +
> +static int uclass_cpu_init(struct uclass *uc)
> +{
> +       struct udevice *dev;
> +       int node;
> +       int ret;
> +
> +       node = fdt_path_offset(gd->fdt_blob, "/cpus");
> +       if (node < 0)
> +               return 0;
> +
> +       ret = device_bind_driver_to_node(dm_root(), "cpu_bus", "cpus", node,
> +                                        &dev);
> +
> +       return ret;
> +}
> +
> +UCLASS_DRIVER(cpu) = {
> +       .id             = UCLASS_CPU,
> +       .name           = "cpu",
> +       .flags          = DM_UC_FLAG_SEQ_ALIAS,
> +       .init           = uclass_cpu_init,
> +};
> diff --git a/include/cpu.h b/include/cpu.h
> new file mode 100644
> index 0000000..46467d0
> --- /dev/null
> +++ b/include/cpu.h
> @@ -0,0 +1,84 @@
> +/*
> + * Copyright (c) 2015 Google, Inc
> + * Written by Simon Glass <sjg@chromium.org>
> + *
> + * SPDX-License-Identifier:    GPL-2.0+
> + */
> +
> +#ifndef __cpu_h
> +#define __cpu_h

Should be capital letters.

> +
> +/**
> + * struct cpu_platdata - platform data for a CPU
> + *
> + * This can be accessed with dev_get_parent_platdata() for any UCLASS_CPU
> + * device.
> + *
> + * @cpu_id:    Platform-specific way of identifying the CPU.
> + */
> +struct cpu_platdata {
> +       int cpu_id;
> +};
> +
> +/* CPU features - mostly just a placeholder for now */
> +enum {
> +       CPU_FEAT_L1_CACHE       = 0,    /* Supports level 1 cache */
> +       CPU_FEAT_MMU            = 1,    /* Supports virtual memory */
> +
> +       CPU_FEAT_COUNT,
> +};
> +
> +/**
> + * struct cpu_info - Information about a CPU
> + *
> + * @cpu_freq:  Current CPU frequency in Hz
> + * @features:  Flags for supported CPU features
> + */
> +struct cpu_info {
> +       ulong cpu_freq;
> +       ulong features;
> +};
> +
> +struct cpu_ops {
> +       /**
> +        * get_desc() - Get a description string for a CPU
> +        *
> +        * @dev:        Device to check (UCLASS_CPU)
> +        * @buf:        Buffer to place string
> +        * @size:       Size of string space
> +        * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
> +        */
> +       int (*get_desc)(struct udevice *dev, char *buf, int size);
> +
> +       /**
> +        * get_info() - Get information about a CPU
> +        *
> +        * @dev:        Device to check (UCLASS_CPU)
> +        * @info:       Returns CPU info
> +        * @return 0 if OK, -ve on error
> +        */
> +       int (*get_info)(struct udevice *dev, struct cpu_info *info);
> +};
> +
> +#define cpu_get_ops(dev)        ((struct cpu_ops *)(dev)->driver->ops)
> +
> +/**
> + * cpu_get_desc() - Get a description string for a CPU
> + *
> + * @dev:       Device to check (UCLASS_CPU)
> + * @buf:       Buffer to place string
> + * @size:      Size of string space
> + * @return 0 if OK, -ENOSPC if buffer is too small, other -ve on error
> + */
> +int cpu_get_desc(struct udevice *dev, char *buf, int size);
> +
> +/**
> + * get_info() - Get information about a CPU

cpu_get_info()

> + *
> + * @dev:       Device to check (UCLASS_CPU)
> + * @info:      Returns CPU info
> + * @return 0 if OK, -ve on error
> + */
> +int cpu_get_info(struct udevice *dev, struct cpu_info *info);
> +
> +#endif
> diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
> index fddfd35..395e25a 100644
> --- a/include/dm/uclass-id.h
> +++ b/include/dm/uclass-id.h
> @@ -45,6 +45,7 @@ enum uclass_id {
>         UCLASS_USB_HUB,         /* USB hub */
>         UCLASS_USB_DEV_GENERIC, /* USB generic device */
>         UCLASS_MASS_STORAGE,    /* Mass storage device */
> +       UCLASS_CPU,             /* CPU, typically part of an SoC */
>
>         UCLASS_COUNT,
>         UCLASS_INVALID = -1,
> --

Regards,
Bin

[U-Boot] [PATCH 09/20] Add a 'cpu' command to print CPU information

[Bin Meng]

On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
> Add a simple command which provides access to a list of available CPUs along
> with descriptions and basic information.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
>  common/Kconfig   |   8 ++++
>  common/Makefile  |   1 +
>  common/cmd_cpu.c | 113 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 122 insertions(+)
>  create mode 100644 common/cmd_cpu.c
>
> diff --git a/common/Kconfig b/common/Kconfig
> index 5d7e48a..15759f7 100644
> --- a/common/Kconfig
> +++ b/common/Kconfig
> @@ -31,6 +31,14 @@ config CMD_CONSOLE
>         help
>           Print console devices and information.
>
> +config CMD_CPU
> +       bool "cpu"
> +       help
> +         Print information about available CPUs. This normally shows the
> +         number of CPUs, type (e.g. manufacturer, architecture, product or
> +         internal name) and clock frequency. Other information may be
> +         available depending on the CPU driver.
> +
>  config CMD_LICENSE
>         bool "license"
>         help
> diff --git a/common/Makefile b/common/Makefile
> index fba3830..9084c73 100644
> --- a/common/Makefile
> +++ b/common/Makefile
> @@ -74,6 +74,7 @@ obj-$(CONFIG_CMD_CBFS) += cmd_cbfs.o
>  obj-$(CONFIG_CMD_CLK) += cmd_clk.o
>  obj-$(CONFIG_CMD_CONSOLE) += cmd_console.o
>  obj-$(CONFIG_CMD_CPLBINFO) += cmd_cplbinfo.o
> +obj-$(CONFIG_CMD_CPU) += cmd_cpu.o
>  obj-$(CONFIG_DATAFLASH_MMC_SELECT) += cmd_dataflash_mmc_mux.o
>  obj-$(CONFIG_CMD_DATE) += cmd_date.o
>  obj-$(CONFIG_CMD_DEMO) += cmd_demo.o
> diff --git a/common/cmd_cpu.c b/common/cmd_cpu.c
> new file mode 100644
> index 0000000..c3e229f
> --- /dev/null
> +++ b/common/cmd_cpu.c
> @@ -0,0 +1,113 @@
> +/*
> + * Copyright (c) 2015 Google, Inc
> + * Written by Simon Glass <sjg@chromium.org>
> + *
> + * SPDX-License-Identifier:    GPL-2.0+
> + */
> +
> +#include <common.h>
> +#include <command.h>
> +#include <cpu.h>
> +#include <dm.h>
> +
> +static const char *cpu_feature_name[CPU_FEAT_COUNT] = {
> +       "L1 cache",
> +       "MMU",
> +};
> +
> +static int print_cpu_list(bool detail)
> +{
> +       struct udevice *dev;
> +       struct uclass *uc;
> +       char buf[100];
> +       int ret;
> +
> +       ret = uclass_get(UCLASS_CPU, &uc);
> +       if (ret) {
> +               printf("Cannot find CPU uclass\n");
> +               return ret;
> +       }
> +       uclass_foreach_dev(dev, uc) {
> +               struct cpu_platdata *plat = dev_get_parent_platdata(dev);
> +               struct cpu_info info;
> +               bool first;
> +               int i;
> +
> +               ret = cpu_get_desc(dev, buf, sizeof(buf));
> +               printf("%3d: %-10s %s\n", dev->seq, dev->name,
> +                      ret ? "<no description>" : buf);
> +               if (!detail)
> +                       continue;
> +               ret = cpu_get_info(dev, &info);
> +               if (ret) {
> +                       printf("\t(no detail available");
> +                       if (ret != -ENOSYS)
> +                               printf(": err=%d\n", ret);
> +                       printf(")\n");
> +                       continue;
> +               }
> +               printf("\tID = %d, freq = ", plat->cpu_id);
> +               print_freq(info.cpu_freq, "");
> +               first = true;
> +               for (i = 0; i < CPU_FEAT_COUNT; i++) {
> +                       if (info.features & (1 << i)) {
> +                               printf("%s%s", first ? ": " : ", ",
> +                                      cpu_feature_name[i]);
> +                               first = false;
> +                       }
> +               }
> +               printf("\n");
> +       }
> +
> +       return 0;
> +}
> +
> +static int do_cpu_list(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
> +{
> +       if (print_cpu_list(false))
> +               return CMD_RET_FAILURE;
> +
> +       return 0;
> +}
> +
> +static int do_cpu_detail(cmd_tbl_t *cmdtp, int flag, int argc,
> +                        char *const argv[])
> +{
> +       if (print_cpu_list(true))
> +               return CMD_RET_FAILURE;
> +
> +       return 0;
> +}
> +
> +static cmd_tbl_t cmd_cpu_sub[] = {
> +       U_BOOT_CMD_MKENT(list, 2, 1, do_cpu_list, "", ""),
> +       U_BOOT_CMD_MKENT(detail, 4, 0, do_cpu_detail, "", ""),
> +};
> +
> +/*
> + * Process a cpu sub-command
> + */
> +static int do_cpu(cmd_tbl_t *cmdtp, int flag, int argc,
> +                      char * const argv[])
> +{
> +       cmd_tbl_t *c = NULL;
> +
> +       /* Strip off leading 'cpu' command argument */
> +       argc--;
> +       argv++;
> +
> +       if (argc)
> +               c = find_cmd_tbl(argv[0], cmd_cpu_sub, ARRAY_SIZE(cmd_cpu_sub));
> +
> +       if (c)
> +               return c->cmd(cmdtp, flag, argc, argv);
> +       else
> +               return CMD_RET_USAGE;
> +}
> +
> +U_BOOT_CMD(
> +       cpu, 2, 1, do_cpu,
> +       "display information about CPUs",
> +       "list   - list available CPUs\n"
> +       "cpu detail     - show CPU detail"
> +);
> --

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

[U-Boot] [PATCH 10/20] x86: Add atomic operations

[Bin Meng]

On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
> Add a subset of this header file from Linux 4.0 to support atomic operations
> in U-Boot.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
>  arch/x86/include/asm/atomic.h | 115 ++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 115 insertions(+)
>  create mode 100644 arch/x86/include/asm/atomic.h
>
> diff --git a/arch/x86/include/asm/atomic.h b/arch/x86/include/asm/atomic.h
> new file mode 100644
> index 0000000..806f787
> --- /dev/null
> +++ b/arch/x86/include/asm/atomic.h
> @@ -0,0 +1,115 @@
> +#ifndef _ASM_X86_ATOMIC_H
> +#define _ASM_X86_ATOMIC_H
> +
> +#include <linux/compiler.h>
> +#include <linux/types.h>
> +#include <asm/processor.h>
> +
> +typedef struct { volatile int counter; } atomic_t;
> +
> +/*
> + * Atomic operations that C can't guarantee us.  Useful for
> + * resource counting etc..
> + */
> +
> +#define ATOMIC_INIT(i) { (i) }
> +
> +/**
> + * atomic_read - read atomic variable
> + * @v: pointer of type atomic_t
> + *
> + * Atomically reads the value of @v.
> + */
> +static inline int atomic_read(const atomic_t *v)
> +{
> +       return ACCESS_ONCE((v)->counter);
> +}
> +
> +/**
> + * atomic_set - set atomic variable
> + * @v: pointer of type atomic_t
> + * @i: required value
> + *
> + * Atomically sets the value of @v to @i.
> + */
> +static inline void atomic_set(atomic_t *v, int i)
> +{
> +       v->counter = i;
> +}
> +
> +/**
> + * atomic_add - add integer to atomic variable
> + * @i: integer value to add
> + * @v: pointer of type atomic_t
> + *
> + * Atomically adds @i to @v.
> + */
> +static inline void atomic_add(int i, atomic_t *v)
> +{
> +       asm volatile(LOCK_PREFIX "addl %1,%0"
> +                    : "+m" (v->counter)
> +                    : "ir" (i));
> +}
> +
> +/**
> + * atomic_sub - subtract integer from atomic variable
> + * @i: integer value to subtract
> + * @v: pointer of type atomic_t
> + *
> + * Atomically subtracts @i from @v.
> + */
> +static inline void atomic_sub(int i, atomic_t *v)
> +{
> +       asm volatile(LOCK_PREFIX "subl %1,%0"
> +                    : "+m" (v->counter)
> +                    : "ir" (i));
> +}
> +
> +/**
> + * atomic_inc - increment atomic variable
> + * @v: pointer of type atomic_t
> + *
> + * Atomically increments @v by 1.
> + */
> +static inline void atomic_inc(atomic_t *v)
> +{
> +       asm volatile(LOCK_PREFIX "incl %0"
> +                    : "+m" (v->counter));
> +}
> +
> +/**
> + * atomic_dec - decrement atomic variable
> + * @v: pointer of type atomic_t
> + *
> + * Atomically decrements @v by 1.
> + */
> +static inline void atomic_dec(atomic_t *v)
> +{
> +       asm volatile(LOCK_PREFIX "decl %0"
> +                    : "+m" (v->counter));
> +}
> +
> +/**
> + * atomic_inc_short - increment of a short integer
> + * @v: pointer to type int
> + *
> + * Atomically adds 1 to @v
> + * Returns the new value of @u
> + */
> +static inline short int atomic_inc_short(short int *v)
> +{
> +       asm(LOCK_PREFIX "addw $1, %0" : "+m" (*v));
> +       return *v;
> +}
> +
> +/* These are x86-specific, used by some header files */
> +#define atomic_clear_mask(mask, addr)                          \
> +       asm volatile(LOCK_PREFIX "andl %0,%1"                   \
> +                    : : "r" (~(mask)), "m" (*(addr)) : "memory")
> +
> +#define atomic_set_mask(mask, addr)                            \
> +       asm volatile(LOCK_PREFIX "orl %0,%1"                    \
> +                    : : "r" ((unsigned)(mask)), "m" (*(addr))  \
> +                    : "memory")
> +
> +#endif /* _ASM_X86_ATOMIC_H */
> --

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

[U-Boot] [PATCH 11/20] x86: Add defines for fixed MTRRs

[Bin Meng]

On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
> Add MSR numbers for the fixed MTRRs.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
>  arch/x86/include/asm/mtrr.h | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
>
> diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
> index fda4eae..3841593 100644
> --- a/arch/x86/include/asm/mtrr.h
> +++ b/arch/x86/include/asm/mtrr.h
> @@ -34,6 +34,20 @@
>  /* Number of MTRRs supported */
>  #define MTRR_COUNT             8
>
> +#define NUM_FIXED_RANGES 88
> +#define RANGES_PER_FIXED_MTRR 8
> +#define MTRR_FIX_64K_00000_MSR 0x250
> +#define MTRR_FIX_16K_80000_MSR 0x258
> +#define MTRR_FIX_16K_A0000_MSR 0x259
> +#define MTRR_FIX_4K_C0000_MSR 0x268
> +#define MTRR_FIX_4K_C8000_MSR 0x269
> +#define MTRR_FIX_4K_D0000_MSR 0x26a
> +#define MTRR_FIX_4K_D8000_MSR 0x26b
> +#define MTRR_FIX_4K_E0000_MSR 0x26c
> +#define MTRR_FIX_4K_E8000_MSR 0x26d
> +#define MTRR_FIX_4K_F0000_MSR 0x26e
> +#define MTRR_FIX_4K_F8000_MSR 0x26f
> +
>  #if !defined(__ASSEMBLER__)
>
>  /**
> --

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

[U-Boot] [PATCH 12/20] x86: Add an mfence macro

[Bin Meng]

Hi Simon,

On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
> Provide access to this x86 instruction from C code.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
>  arch/x86/include/asm/cpu.h | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
> index c839291..37aa6b9 100644
> --- a/arch/x86/include/asm/cpu.h
> +++ b/arch/x86/include/asm/cpu.h
> @@ -151,6 +151,11 @@ static inline int flag_is_changeable_p(uint32_t flag)
>         return ((f1^f2) & flag) != 0;
>  }
>
> +static inline void mfence(void)
> +{
> +       __asm__ __volatile__("mfence\t\n" : : : "memory");

Do we need "\t\n"?

> +}
> +
>  /**
>   * cpu_enable_paging_pae() - Enable PAE-paging
>   *
> --

Regards,
Bin

[U-Boot] [PATCH 13/20] x86: Store the GDT pointer in global_data

[Bin Meng]

On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
> When we start up additional CPUs we want them to use the same Global
> Descriptor Table. Store the address of this in global_data so we can
> reference it later.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
>  arch/x86/cpu/cpu.c                 | 1 +
>  arch/x86/include/asm/global_data.h | 1 +
>  2 files changed, 2 insertions(+)
>
> diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c
> index 13b3baa..74bfed2 100644
> --- a/arch/x86/cpu/cpu.c
> +++ b/arch/x86/cpu/cpu.c
> @@ -133,6 +133,7 @@ static void load_gdt(const u64 *boot_gdt, u16 num_entries)
>
>  void setup_gdt(gd_t *id, u64 *gdt_addr)
>  {
> +       id->arch.gdt = gdt_addr;
>         /* CS: code, read/execute, 4 GB, base 0 */
>         gdt_addr[X86_GDT_ENTRY_32BIT_CS] = GDT_ENTRY(0xc09b, 0, 0xfffff);
>
> diff --git a/arch/x86/include/asm/global_data.h b/arch/x86/include/asm/global_data.h
> index 5ee06eb..4d9eac6 100644
> --- a/arch/x86/include/asm/global_data.h
> +++ b/arch/x86/include/asm/global_data.h
> @@ -68,6 +68,7 @@ struct arch_global_data {
>         /* MRC training data to save for the next boot */
>         char *mrc_output;
>         unsigned int mrc_output_len;
> +       void *gdt;                      /* Global descriptor table */
>  };
>
>  #endif
> --

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

[U-Boot] [PATCH 14/20] x86: Provide access to the IDT

[Bin Meng]

Hi Simon,

On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
> Add a function to return the address of the Interrupt Descriptor Table.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
>  arch/x86/cpu/interrupts.c        | 5 +++++
>  arch/x86/include/asm/interrupt.h | 2 ++
>  2 files changed, 7 insertions(+)
>
> diff --git a/arch/x86/cpu/interrupts.c b/arch/x86/cpu/interrupts.c
> index a21d2a6..c777d36 100644
> --- a/arch/x86/cpu/interrupts.c
> +++ b/arch/x86/cpu/interrupts.c
> @@ -147,6 +147,11 @@ int cpu_init_interrupts(void)
>         return 0;
>  }
>
> +void *x86_get_idt(void)
> +{
> +       return &idt_ptr;
> +}
> +

idt_ptr is not declared as static, so this is unneeded? Or should we
change it to static?

>  void __do_irq(int irq)
>  {
>         printf("Unhandled IRQ : %d\n", irq);
> diff --git a/arch/x86/include/asm/interrupt.h b/arch/x86/include/asm/interrupt.h
> index 25abde7..0a75f89 100644
> --- a/arch/x86/include/asm/interrupt.h
> +++ b/arch/x86/include/asm/interrupt.h
> @@ -38,4 +38,6 @@ extern char exception_stack[];
>   */
>  void configure_irq_trigger(int int_num, bool is_level_triggered);
>
> +void *x86_get_idt(void);
> +
>  #endif
> --

Regards,
Bin

[U-Boot] [PATCH 14/20] x86: Provide access to the IDT

[Simon Glass]

Hi Bin,

On 28 April 2015 at 02:16, Bin Meng <bmeng.cn@gmail.com> wrote:
> Hi Simon,
>
> On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
>> Add a function to return the address of the Interrupt Descriptor Table.
>>
>> Signed-off-by: Simon Glass <sjg@chromium.org>
>> ---
>>
>>  arch/x86/cpu/interrupts.c        | 5 +++++
>>  arch/x86/include/asm/interrupt.h | 2 ++
>>  2 files changed, 7 insertions(+)
>>
>> diff --git a/arch/x86/cpu/interrupts.c b/arch/x86/cpu/interrupts.c
>> index a21d2a6..c777d36 100644
>> --- a/arch/x86/cpu/interrupts.c
>> +++ b/arch/x86/cpu/interrupts.c
>> @@ -147,6 +147,11 @@ int cpu_init_interrupts(void)
>>         return 0;
>>  }
>>
>> +void *x86_get_idt(void)
>> +{
>> +       return &idt_ptr;
>> +}
>> +
>
> idt_ptr is not declared as static, so this is unneeded? Or should we
> change it to static?

I think it is better to access it via a function. It is used from
assembler so I would rather not make it static. Any thoughts?

>
>>  void __do_irq(int irq)
>>  {
>>         printf("Unhandled IRQ : %d\n", irq);
>> diff --git a/arch/x86/include/asm/interrupt.h b/arch/x86/include/asm/interrupt.h
>> index 25abde7..0a75f89 100644
>> --- a/arch/x86/include/asm/interrupt.h
>> +++ b/arch/x86/include/asm/interrupt.h
>> @@ -38,4 +38,6 @@ extern char exception_stack[];
>>   */
>>  void configure_irq_trigger(int int_num, bool is_level_triggered);
>>
>> +void *x86_get_idt(void);
>> +
>>  #endif
>> --

Regards,
Simon

[U-Boot] [PATCH 14/20] x86: Provide access to the IDT

[Bin Meng]

Hi Simon,

On Wed, Apr 29, 2015 at 10:08 AM, Simon Glass <sjg@chromium.org> wrote:
> Hi Bin,
>
> On 28 April 2015 at 02:16, Bin Meng <bmeng.cn@gmail.com> wrote:
>> Hi Simon,
>>
>> On Tue, Apr 28, 2015 at 6:48 AM, Simon Glass <sjg@chromium.org> wrote:
>>> Add a function to return the address of the Interrupt Descriptor Table.
>>>
>>> Signed-off-by: Simon Glass <sjg@chromium.org>
>>> ---
>>>
>>>  arch/x86/cpu/interrupts.c        | 5 +++++
>>>  arch/x86/include/asm/interrupt.h | 2 ++
>>>  2 files changed, 7 insertions(+)
>>>
>>> diff --git a/arch/x86/cpu/interrupts.c b/arch/x86/cpu/interrupts.c
>>> index a21d2a6..c777d36 100644
>>> --- a/arch/x86/cpu/interrupts.c
>>> +++ b/arch/x86/cpu/interrupts.c
>>> @@ -147,6 +147,11 @@ int cpu_init_interrupts(void)
>>>         return 0;
>>>  }
>>>
>>> +void *x86_get_idt(void)
>>> +{
>>> +       return &idt_ptr;
>>> +}
>>> +
>>
>> idt_ptr is not declared as static, so this is unneeded? Or should we
>> change it to static?
>
> I think it is better to access it via a function. It is used from
> assembler so I would rather not make it static. Any thoughts?
>

OK, fair enough.

[snip]

Regards,
Bin