x86: Add SMBIOS table support

System Management BIOS (SMBIOS) is a specification for how
motherboard and system vendors present management information
about their products in a standard format by extending the BIOS
interface on Intel architecture systems. As of today the latest
spec is 3.0 and can be downloaded from DMTF website. This commit
adds a simple and minimum required implementation.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>

arch/x86/Kconfig

@@ -358,6 +358,17 @@ config GENERATE_ACPI_TABLE
 	  by the operating system. It defines platform-independent interfaces
 	  for configuration and power management monitoring.
 
+config GENERATE_SMBIOS_TABLE
+	bool "Generate an SMBIOS (System Management BIOS) table"
+	default y
+	help
+	  The System Management BIOS (SMBIOS) specification addresses how
+	  motherboard and system vendors present management information about
+	  their products in a standard format by extending the BIOS interface
+	  on Intel architecture systems.
+
+	  Check http://www.dmtf.org/standards/smbios for details.
+
 endmenu
 
 config MAX_PIRQ_LINKS

arch/x86/include/asm/smbios.h

@@ -0,0 +1,236 @@
+/*
+ * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * Adapted from coreboot src/include/smbios.h
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _SMBIOS_H_
+#define _SMBIOS_H_
+
+/* SMBIOS spec version implemented */
+#define SMBIOS_MAJOR_VER	3
+#define SMBIOS_MINOR_VER	0
+
+/* SMBIOS structure types */
+enum {
+	SMBIOS_BIOS_INFORMATION = 0,
+	SMBIOS_SYSTEM_INFORMATION = 1,
+	SMBIOS_BOARD_INFORMATION = 2,
+	SMBIOS_SYSTEM_ENCLOSURE = 3,
+	SMBIOS_PROCESSOR_INFORMATION = 4,
+	SMBIOS_CACHE_INFORMATION = 7,
+	SMBIOS_SYSTEM_SLOTS = 9,
+	SMBIOS_PHYS_MEMORY_ARRAY = 16,
+	SMBIOS_MEMORY_DEVICE = 17,
+	SMBIOS_MEMORY_ARRAY_MAPPED_ADDRESS = 19,
+	SMBIOS_SYSTEM_BOOT_INFORMATION = 32,
+	SMBIOS_END_OF_TABLE = 127
+};
+
+#define SMBIOS_INTERMEDIATE_OFFSET	16
+#define SMBIOS_STRUCT_EOS_BYTES		2
+
+struct __packed smbios_entry {
+	u8 anchor[4];
+	u8 checksum;
+	u8 length;
+	u8 major_ver;
+	u8 minor_ver;
+	u16 max_struct_size;
+	u8 entry_point_rev;
+	u8 formatted_area[5];
+	u8 intermediate_anchor[5];
+	u8 intermediate_checksum;
+	u16 struct_table_length;
+	u32 struct_table_address;
+	u16 struct_count;
+	u8 bcd_rev;
+};
+
+/* BIOS characteristics */
+#define BIOS_CHARACTERISTICS_PCI_SUPPORTED	(1 << 7)
+#define BIOS_CHARACTERISTICS_UPGRADEABLE	(1 << 11)
+#define BIOS_CHARACTERISTICS_SELECTABLE_BOOT	(1 << 16)
+
+#define BIOS_CHARACTERISTICS_EXT1_ACPI		(1 << 0)
+#define BIOS_CHARACTERISTICS_EXT2_TARGET	(1 << 2)
+
+struct __packed smbios_type0 {
+	u8 type;
+	u8 length;
+	u16 handle;
+	u8 vendor;
+	u8 bios_ver;
+	u16 bios_start_segment;
+	u8 bios_release_date;
+	u8 bios_rom_size;
+	u64 bios_characteristics;
+	u8 bios_characteristics_ext1;
+	u8 bios_characteristics_ext2;
+	u8 bios_major_release;
+	u8 bios_minor_release;
+	u8 ec_major_release;
+	u8 ec_minor_release;
+	char eos[SMBIOS_STRUCT_EOS_BYTES];
+};
+
+struct __packed smbios_type1 {
+	u8 type;
+	u8 length;
+	u16 handle;
+	u8 manufacturer;
+	u8 product_name;
+	u8 version;
+	u8 serial_number;
+	u8 uuid[16];
+	u8 wakeup_type;
+	u8 sku_number;
+	u8 family;
+	char eos[SMBIOS_STRUCT_EOS_BYTES];
+};
+
+#define SMBIOS_BOARD_FEATURE_HOSTING	(1 << 0)
+#define SMBIOS_BOARD_MOTHERBOARD	10
+
+struct __packed smbios_type2 {
+	u8 type;
+	u8 length;
+	u16 handle;
+	u8 manufacturer;
+	u8 product_name;
+	u8 version;
+	u8 serial_number;
+	u8 asset_tag_number;
+	u8 feature_flags;
+	u8 chassis_location;
+	u16 chassis_handle;
+	u8 board_type;
+	char eos[SMBIOS_STRUCT_EOS_BYTES];
+};
+
+#define SMBIOS_ENCLOSURE_DESKTOP	3
+#define SMBIOS_STATE_SAFE		3
+#define SMBIOS_SECURITY_NONE		3
+
+struct __packed smbios_type3 {
+	u8 type;
+	u8 length;
+	u16 handle;
+	u8 manufacturer;
+	u8 chassis_type;
+	u8 version;
+	u8 serial_number;
+	u8 asset_tag_number;
+	u8 bootup_state;
+	u8 power_supply_state;
+	u8 thermal_state;
+	u8 security_status;
+	u32 oem_defined;
+	u8 height;
+	u8 number_of_power_cords;
+	u8 element_count;
+	u8 element_record_length;
+	char eos[SMBIOS_STRUCT_EOS_BYTES];
+};
+
+#define SMBIOS_PROCESSOR_TYPE_CENTRAL	3
+#define SMBIOS_PROCESSOR_STATUS_ENABLED	1
+#define SMBIOS_PROCESSOR_UPGRADE_NONE	6
+
+struct __packed smbios_type4 {
+	u8 type;
+	u8 length;
+	u16 handle;
+	u8 socket_designation;
+	u8 processor_type;
+	u8 processor_family;
+	u8 processor_manufacturer;
+	u32 processor_id[2];
+	u8 processor_version;
+	u8 voltage;
+	u16 external_clock;
+	u16 max_speed;
+	u16 current_speed;
+	u8 status;
+	u8 processor_upgrade;
+	u16 l1_cache_handle;
+	u16 l2_cache_handle;
+	u16 l3_cache_handle;
+	u8 serial_number;
+	u8 asset_tag;
+	u8 part_number;
+	u8 core_count;
+	u8 core_enabled;
+	u8 thread_count;
+	u16 processor_characteristics;
+	u16 processor_family2;
+	u16 core_count2;
+	u16 core_enabled2;
+	u16 thread_count2;
+	char eos[SMBIOS_STRUCT_EOS_BYTES];
+};
+
+struct __packed smbios_type32 {
+	u8 type;
+	u8 length;
+	u16 handle;
+	u8 reserved[6];
+	u8 boot_status;
+	u8 eos[SMBIOS_STRUCT_EOS_BYTES];
+};
+
+struct __packed smbios_type127 {
+	u8 type;
+	u8 length;
+	u16 handle;
+	u8 eos[SMBIOS_STRUCT_EOS_BYTES];
+};
+
+struct __packed smbios_header {
+	u8 type;
+	u8 length;
+	u16 handle;
+};
+
+/**
+ * fill_smbios_header() - Fill the header of an SMBIOS table
+ *
+ * This fills the header of an SMBIOS table structure.
+ *
+ * @table:	start address of the structure
+ * @type:	the type of structure
+ * @length:	the length of the formatted area of the structure
+ * @handle:	the structure's handle, a unique 16-bit number
+ */
+static inline void fill_smbios_header(void *table, int type,
+				      int length, int handle)
+{
+	struct smbios_header *header = table;
+
+	header->type = type;
+	header->length = length - SMBIOS_STRUCT_EOS_BYTES;
+	header->handle = handle;
+}
+
+/**
+ * Function prototype to write a specific type of SMBIOS structure
+ *
+ * @addr:	start address to write the structure
+ * @handle:	the structure's handle, a unique 16-bit number
+ * @return:	size of the structure
+ */
+typedef int (*smbios_write_type)(u32 *addr, int handle);
+
+/**
+ * write_smbios_table() - Write SMBIOS table
+ *
+ * This writes SMBIOS table at a given address.
+ *
+ * @addr:	start address to write SMBIOS table
+ * @return:	end address of SMBIOS table
+ */
+u32 write_smbios_table(u32 addr);
+
+#endif /* _SMBIOS_H_ */

arch/x86/lib/Makefile

@@ -30,6 +30,7 @@ obj-y	+= relocate.o
 obj-y += physmem.o
 obj-$(CONFIG_X86_RAMTEST) += ramtest.o
 obj-y += sfi.o
+obj-$(CONFIG_GENERATE_SMBIOS_TABLE) += smbios.o
 obj-y	+= string.o
 obj-$(CONFIG_GENERATE_ACPI_TABLE) += acpi_table.o
 obj-y	+= tables.o

arch/x86/lib/smbios.c

@@ -0,0 +1,269 @@
+/*
+ * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * Adapted from coreboot src/arch/x86/smbios.c
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <version.h>
+#include <asm/cpu.h>
+#include <asm/smbios.h>
+#include <asm/tables.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/**
+ * smbios_add_string() - add a string to the string area
+ *
+ * This adds a string to the string area which is appended directly after
+ * the formatted portion of an SMBIOS structure.
+ *
+ * @start:	string area start address
+ * @str:	string to add
+ * @return:	string number in the string area
+ */
+static int smbios_add_string(char *start, const char *str)
+{
+	int i = 1;
+	char *p = start;
+
+	for (;;) {
+		if (!*p) {
+			strcpy(p, str);
+			p += strlen(str);
+			*p++ = '\0';
+			*p++ = '\0';
+
+			return i;
+		}
+
+		if (!strcmp(p, str))
+			return i;
+
+		p += strlen(p) + 1;
+		i++;
+	}
+}
+
+/**
+ * smbios_string_table_len() - compute the string area size
+ *
+ * This computes the size of the string area including the string terminator.
+ *
+ * @start:	string area start address
+ * @return:	string area size
+ */
+static int smbios_string_table_len(char *start)
+{
+	char *p = start;
+	int i, len = 0;
+
+	while (*p) {
+		i = strlen(p) + 1;
+		p += i;
+		len += i;
+	}
+
+	return len + 1;
+}
+
+static int smbios_write_type0(u32 *current, int handle)
+{
+	struct smbios_type0 *t = (struct smbios_type0 *)*current;
+	int len = sizeof(struct smbios_type0);
+
+	memset(t, 0, sizeof(struct smbios_type0));
+	fill_smbios_header(t, SMBIOS_BIOS_INFORMATION, len, handle);
+	t->vendor = smbios_add_string(t->eos, "U-Boot");
+	t->bios_ver = smbios_add_string(t->eos, PLAIN_VERSION);
+	t->bios_release_date = smbios_add_string(t->eos, U_BOOT_DMI_DATE);
+	t->bios_rom_size = (CONFIG_ROM_SIZE / 65536) - 1;
+	t->bios_characteristics = BIOS_CHARACTERISTICS_PCI_SUPPORTED |
+				  BIOS_CHARACTERISTICS_SELECTABLE_BOOT |
+				  BIOS_CHARACTERISTICS_UPGRADEABLE;
+#ifdef CONFIG_GENERATE_ACPI_TABLE
+	t->bios_characteristics_ext1 = BIOS_CHARACTERISTICS_EXT1_ACPI;
+#endif
+	t->bios_characteristics_ext2 = BIOS_CHARACTERISTICS_EXT2_TARGET;
+	t->bios_major_release = 0xff;
+	t->bios_minor_release = 0xff;
+	t->ec_major_release = 0xff;
+	t->ec_minor_release = 0xff;
+
+	len = t->length + smbios_string_table_len(t->eos);
+	*current += len;
+
+	return len;
+}
+
+static int smbios_write_type1(u32 *current, int handle)
+{
+	struct smbios_type1 *t = (struct smbios_type1 *)*current;
+	int len = sizeof(struct smbios_type1);
+
+	memset(t, 0, sizeof(struct smbios_type1));
+	fill_smbios_header(t, SMBIOS_SYSTEM_INFORMATION, len, handle);
+	t->manufacturer = smbios_add_string(t->eos, CONFIG_SYS_VENDOR);
+	t->product_name = smbios_add_string(t->eos, CONFIG_SYS_BOARD);
+
+	len = t->length + smbios_string_table_len(t->eos);
+	*current += len;
+
+	return len;
+}
+
+static int smbios_write_type2(u32 *current, int handle)
+{
+	struct smbios_type2 *t = (struct smbios_type2 *)*current;
+	int len = sizeof(struct smbios_type2);
+
+	memset(t, 0, sizeof(struct smbios_type2));
+	fill_smbios_header(t, SMBIOS_BOARD_INFORMATION, len, handle);
+	t->manufacturer = smbios_add_string(t->eos, CONFIG_SYS_VENDOR);
+	t->product_name = smbios_add_string(t->eos, CONFIG_SYS_BOARD);
+	t->feature_flags = SMBIOS_BOARD_FEATURE_HOSTING;
+	t->board_type = SMBIOS_BOARD_MOTHERBOARD;
+
+	len = t->length + smbios_string_table_len(t->eos);
+	*current += len;
+
+	return len;
+}
+
+static int smbios_write_type3(u32 *current, int handle)
+{
+	struct smbios_type3 *t = (struct smbios_type3 *)*current;
+	int len = sizeof(struct smbios_type3);
+
+	memset(t, 0, sizeof(struct smbios_type3));
+	fill_smbios_header(t, SMBIOS_SYSTEM_ENCLOSURE, len, handle);
+	t->manufacturer = smbios_add_string(t->eos, CONFIG_SYS_VENDOR);
+	t->chassis_type = SMBIOS_ENCLOSURE_DESKTOP;
+	t->bootup_state = SMBIOS_STATE_SAFE;
+	t->power_supply_state = SMBIOS_STATE_SAFE;
+	t->thermal_state = SMBIOS_STATE_SAFE;
+	t->security_status = SMBIOS_SECURITY_NONE;
+
+	len = t->length + smbios_string_table_len(t->eos);
+	*current += len;
+
+	return len;
+}
+
+static int smbios_write_type4(u32 *current, int handle)
+{
+	struct smbios_type4 *t = (struct smbios_type4 *)*current;
+	int len = sizeof(struct smbios_type4);
+	const char *vendor;
+	char *name;
+	char processor_name[CPU_MAX_NAME_LEN];
+	struct cpuid_result res;
+
+	memset(t, 0, sizeof(struct smbios_type4));
+	fill_smbios_header(t, SMBIOS_PROCESSOR_INFORMATION, len, handle);
+	t->processor_type = SMBIOS_PROCESSOR_TYPE_CENTRAL;
+	t->processor_family = gd->arch.x86;
+	vendor = cpu_vendor_name(gd->arch.x86_vendor);
+	t->processor_manufacturer = smbios_add_string(t->eos, vendor);
+	res = cpuid(1);
+	t->processor_id[0] = res.eax;
+	t->processor_id[1] = res.edx;
+	name = cpu_get_name(processor_name);
+	t->processor_version = smbios_add_string(t->eos, name);
+	t->status = SMBIOS_PROCESSOR_STATUS_ENABLED;
+	t->processor_upgrade = SMBIOS_PROCESSOR_UPGRADE_NONE;
+	t->l1_cache_handle = 0xffff;
+	t->l2_cache_handle = 0xffff;
+	t->l3_cache_handle = 0xffff;
+	t->processor_family2 = t->processor_family;
+
+	len = t->length + smbios_string_table_len(t->eos);
+	*current += len;
+
+	return len;
+}
+
+static int smbios_write_type32(u32 *current, int handle)
+{
+	struct smbios_type32 *t = (struct smbios_type32 *)*current;
+	int len = sizeof(struct smbios_type32);
+
+	memset(t, 0, sizeof(struct smbios_type32));
+	fill_smbios_header(t, SMBIOS_SYSTEM_BOOT_INFORMATION, len, handle);
+
+	*current += len;
+
+	return len;
+}
+
+static int smbios_write_type127(u32 *current, int handle)
+{
+	struct smbios_type127 *t = (struct smbios_type127 *)*current;
+	int len = sizeof(struct smbios_type127);
+
+	memset(t, 0, sizeof(struct smbios_type127));
+	fill_smbios_header(t, SMBIOS_END_OF_TABLE, len, handle);
+
+	*current += len;
+
+	return len;
+}
+
+static smbios_write_type smbios_write_funcs[] = {
+	smbios_write_type0,
+	smbios_write_type1,
+	smbios_write_type2,
+	smbios_write_type3,
+	smbios_write_type4,
+	smbios_write_type32,
+	smbios_write_type127
+};
+
+u32 write_smbios_table(u32 addr)
+{
+	struct smbios_entry *se;
+	u32 tables;
+	int len = 0;
+	int max_struct_size = 0;
+	int handle = 0;
+	char *istart;
+	int isize;
+	int i;
+
+	/* 16 byte align the table address */
+	addr = ALIGN(addr, 16);
+
+	se = (struct smbios_entry *)addr;
+	memset(se, 0, sizeof(struct smbios_entry));
+
+	addr += sizeof(struct smbios_entry);
+	addr = ALIGN(addr, 16);
+	tables = addr;
+
+	/* populate minimum required tables */
+	for (i = 0; i < ARRAY_SIZE(smbios_write_funcs); i++) {
+		int tmp = smbios_write_funcs[i](&addr, handle++);
+		max_struct_size = max(max_struct_size, tmp);
+		len += tmp;
+	}
+
+	memcpy(se->anchor, "_SM_", 4);
+	se->length = sizeof(struct smbios_entry);
+	se->major_ver = SMBIOS_MAJOR_VER;
+	se->minor_ver = SMBIOS_MINOR_VER;
+	se->max_struct_size = max_struct_size;
+	memcpy(se->intermediate_anchor, "_DMI_", 5);
+	se->struct_table_length = len;
+	se->struct_table_address = tables;
+	se->struct_count = handle;
+
+	/* calculate checksums */
+	istart = (char *)se + SMBIOS_INTERMEDIATE_OFFSET;
+	isize = sizeof(struct smbios_entry) - SMBIOS_INTERMEDIATE_OFFSET;
+	se->intermediate_checksum = table_compute_checksum(istart, isize);
+	se->checksum = table_compute_checksum(se, sizeof(struct smbios_entry));
+
+	return addr;
+}

arch/x86/lib/tables.c

@@ -7,6 +7,7 @@
 #include <common.h>
 #include <asm/sfi.h>
 #include <asm/mpspec.h>
+#include <asm/smbios.h>
 #include <asm/tables.h>
 #include <asm/acpi_table.h>
 
@@ -56,4 +57,8 @@ void write_tables(void)
 	rom_table_end = write_acpi_tables(rom_table_end);
 	rom_table_end = ALIGN(rom_table_end, 1024);
 #endif
+#ifdef CONFIG_GENERATE_SMBIOS_TABLE
+	rom_table_end = write_smbios_table(rom_table_end);
+	rom_table_end = ALIGN(rom_table_end, 1024);
+#endif
 }

doc/README.x86

@@ -764,7 +764,6 @@ TODO List
 - Audio
 - Chrome OS verified boot
 - SMI and ACPI support, to provide platform info and facilities to Linux
-- Desktop Management Interface (DMI) [15] support
 
 References
 ----------
@@ -782,4 +781,3 @@ References
 [12] http://events.linuxfoundation.org/sites/events/files/slides/chromeos_and_diy_vboot_0.pdf
 [13] http://events.linuxfoundation.org/sites/events/files/slides/elce-2014.pdf
 [14] doc/device-tree-bindings/misc/intel,irq-router.txt
-[15] http://en.wikipedia.org/wiki/Desktop_Management_Interface