[U-Boot] [PATCH 07/20] x86: Add support for the Simple Firmware Interface (SFI)
Simon Glass
sjg at chromium.org
Tue Apr 28 00:48:10 CEST 2015
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 at 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 at 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
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