smbios: copy QEMU tables

QEMU provides SMBIOS tables with detailed information. We should not try to
replicate them in U-Boot.

If we want to inform about U-Boot, we can add a Firmware Inventory
Information (type 45) table in future.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

arch/x86/lib/tables.c

@@ -62,7 +62,7 @@ static struct table_info table_list[] = {
 #ifdef CONFIG_GENERATE_ACPI_TABLE
 	{ "acpi", write_acpi_tables, BLOBLISTT_ACPI_TABLES, 0x10000, 0x1000},
 #endif
-#ifdef CONFIG_GENERATE_SMBIOS_TABLE
+#if defined(CONFIG_GENERATE_SMBIOS_TABLE) && !defined(CONFIG_QFW_SMBIOS)
 	{ "smbios", write_smbios_table, BLOBLISTT_SMBIOS_TABLES, 0x1000, 0x100},
 #endif
 };

drivers/misc/Kconfig

@@ -554,6 +554,13 @@ config QFW_MMIO
 	  Hidden option to enable MMIO QEMU fw_cfg interface. This will be
 	  selected by the appropriate QEMU board.
 
+config QFW_SMBIOS
+	bool
+	default y
+	depends on QFW && SMBIOS && !SANDBOX
+	help
+	  Hidden option to read SMBIOS tables from QEMU.
+
 config I2C_EEPROM
 	bool "Enable driver for generic I2C-attached EEPROMs"
 	depends on MISC

drivers/misc/Makefile

@@ -65,6 +65,7 @@ obj-y += qfw.o
 obj-$(CONFIG_QFW_ACPI) += qfw_acpi.o
 obj-$(CONFIG_QFW_PIO) += qfw_pio.o
 obj-$(CONFIG_QFW_MMIO) += qfw_mmio.o
+obj-$(CONFIG_QFW_SMBIOS) += qfw_smbios.o
 obj-$(CONFIG_SANDBOX) += qfw_sandbox.o
 endif
 obj-$(CONFIG_ROCKCHIP_EFUSE) += rockchip-efuse.o

drivers/misc/qfw_smbios.c

@@ -0,0 +1,197 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * (C) Copyright 2023 Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
+ */
+
+#define LOG_CATEGORY UCLASS_QFW
+
+#include <efi_loader.h>
+#include <errno.h>
+#include <log.h>
+#include <malloc.h>
+#include <mapmem.h>
+#include <qfw.h>
+#include <smbios.h>
+#include <tables_csum.h>
+#include <linux/sizes.h>
+#include <asm/global_data.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/**
+ * qfw_load_smbios_table() - load a QEMU firmware file
+ *
+ * @dev:	QEMU firmware device
+ * @size:	parameter to return the size of the loaded table
+ * @name:	name of the table to load
+ * Return:	address of the loaded table, NULL on error
+ */
+static void *qfw_load_smbios_table(struct udevice *dev, uint32_t *size,
+				   char *name)
+{
+	struct fw_file *file;
+	struct bios_linker_entry *table;
+
+	file = qfw_find_file(dev, name);
+	if (!file) {
+		log_debug("Can't find %s\n", name);
+		return NULL;
+	}
+
+	*size = be32_to_cpu(file->cfg.size);
+
+	table = malloc(*size);
+	if (!table) {
+		log_err("Out of memory\n");
+		return NULL;
+	}
+
+	qfw_read_entry(dev, be16_to_cpu(file->cfg.select), *size, table);
+
+	return table;
+}
+
+/**
+ * qfw_parse_smbios_anchor() - parse QEMU's SMBIOS anchor
+ *
+ * @dev:	QEMU firmware device
+ * @entry:	SMBIOS 3 structure to be filled from QEMU's anchor
+ * Return:	0 for success, -ve on error
+ */
+static int qfw_parse_smbios_anchor(struct udevice *dev,
+				   struct smbios3_entry *entry)
+{
+	void *table;
+	uint32_t size;
+	struct smbios_entry *entry2;
+	struct smbios3_entry *entry3;
+	const char smbios_sig[] = "_SM_";
+	const char smbios3_sig[] = "_SM3_";
+	int ret = 0;
+
+	table = qfw_load_smbios_table(dev, &size, "etc/smbios/smbios-anchor");
+	if (!table)
+		return -ENOMEM;
+	if (!memcmp(table, smbios3_sig, sizeof(smbios3_sig) - 1)) {
+		entry3 = table;
+		if (entry3->length != sizeof(struct smbios3_entry)) {
+			ret = -ENOENT;
+			goto out;
+		}
+		memcpy(entry, entry3, sizeof(struct smbios3_entry));
+	} else if (!memcmp(table, smbios_sig, sizeof(smbios_sig) - 1)) {
+		entry2 = table;
+		if (entry2->length != sizeof(struct smbios_entry)) {
+			ret = -ENOENT;
+			goto out;
+		}
+		memset(entry, 0, sizeof(struct smbios3_entry));
+		memcpy(entry, smbios3_sig, sizeof(smbios3_sig));
+		entry->length = sizeof(struct smbios3_entry);
+		entry->major_ver = entry2->major_ver;
+		entry->minor_ver = entry2->minor_ver;
+		entry->max_struct_size = entry2->max_struct_size;
+	} else {
+		ret = -ENOENT;
+		goto out;
+	}
+	ret = 0;
+out:
+	free(table);
+
+	return ret;
+}
+
+/**
+ * qfw_write_smbios_tables() - copy SMBIOS tables from QEMU
+ *
+ * @addr:	target buffer
+ * @size:	size of target buffer
+ * Return:	0 for success, -ve on error
+ */
+static int qfw_write_smbios_tables(u8 *addr, uint32_t size)
+{
+	int ret;
+	struct udevice *dev;
+	struct smbios3_entry *entry = (void *)addr;
+	void *table;
+	uint32_t table_size;
+
+	ret = qfw_get_dev(&dev);
+	if (ret) {
+		log_err("No QEMU firmware device\n");
+		return ret;
+	}
+
+	ret = qfw_read_firmware_list(dev);
+	if (ret) {
+		log_err("Can't read firmware file list\n");
+		return ret;
+	}
+
+	ret = qfw_parse_smbios_anchor(dev, entry);
+	if (ret) {
+		log_debug("Can't parse anchor\n");
+		return ret;
+	}
+
+	addr += entry->length;
+	entry->struct_table_address = (uintptr_t)addr;
+	entry->checksum = 0;
+	entry->checksum = table_compute_checksum(entry,
+						 sizeof(struct smbios3_entry));
+
+	table = qfw_load_smbios_table(dev, &table_size,
+				      "etc/smbios/smbios-tables");
+	if (table_size + sizeof(struct smbios3_entry) > size) {
+		free(table);
+		return -ENOMEM;
+	}
+	memcpy(addr, table, table_size);
+	free(table);
+
+	return 0;
+}
+
+/**
+ * qfw_evt_write_smbios_tables() - event handler for copying QEMU SMBIOS tables
+ *
+ * Return:	0 on success, -ve on error (only out of memory)
+ */
+static int qfw_evt_write_smbios_tables(void)
+{
+	phys_addr_t addr;
+	void *ptr;
+	int ret;
+	/*
+	 * TODO:
+	 * This size is currently hard coded in lib/efi_loader/efi_smbios.c.
+	 * We need a field in global data for the size.
+	 */
+	uint32_t size = SZ_4K;
+
+	/* Reserve 64K for SMBIOS tables, aligned to a 4K boundary */
+	ptr = memalign(SZ_4K, size);
+	if (!ptr) {
+		log_err("Out of memory\n");
+		return -ENOMEM;
+	}
+	addr = map_to_sysmem(ptr);
+
+	/* Generate SMBIOS tables */
+	ret = qfw_write_smbios_tables(ptr, size);
+	if (ret) {
+		if (CONFIG_IS_ENABLED(GENERATE_SMBIOS_TABLE)) {
+			log_info("Falling back to U-Boot generated SMBIOS tables\n");
+			write_smbios_table(addr);
+		}
+	} else {
+		log_debug("SMBIOS tables copied from QEMU\n");
+	}
+
+	gd_set_smbios_start(addr);
+
+	return 0;
+}
+
+EVENT_SPY_SIMPLE(EVT_LAST_STAGE_INIT, qfw_evt_write_smbios_tables);

lib/efi_loader/efi_smbios.c

@@ -60,7 +60,9 @@ static int install_smbios_table(void)
 	ulong addr;
 	void *buf;
 
-	if (!IS_ENABLED(CONFIG_GENERATE_SMBIOS_TABLE) || IS_ENABLED(CONFIG_X86))
+	if (!IS_ENABLED(CONFIG_GENERATE_SMBIOS_TABLE) ||
+	    IS_ENABLED(CONFIG_X86) ||
+	    IS_ENABLED(CONFIG_QFW_SMBIOS))
 		return 0;
 
 	/* Align the table to a 4KB boundary to keep EFI happy */