x86: Add support for the Simple Firmware Interface (SFI)
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>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index f3a600e..467fe25 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -393,6 +393,20 @@
It specifies the interrupt router information as well how all the PCI
devices' interrupt pins are wired to PIRQs.
+config GENERATE_SFI_TABLE
+ bool "Generate a SFI (Simple Firmware Interface) table"
+ 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.
+
+ U-Boot writes this table in write_sfi_table() just before booting
+ the OS.
+
+ For more information, see http://simplefirmware.org
+
endmenu
config MAX_PIRQ_LINKS
diff --git a/arch/x86/include/asm/sfi.h b/arch/x86/include/asm/sfi.h
new file mode 100644
index 0000000..d1f0f0c
--- /dev/null
+++ b/arch/x86/include/asm/sfi.h
@@ -0,0 +1,137 @@
+/*
+ * 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_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_TABLE_MAX_ENTRIES 16
+
+#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,
+ * as they are provided by the BIOS.
+ */
+struct __packed 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];
+};
+
+struct __packed sfi_table_simple {
+ struct sfi_table_header header;
+ u64 pentry[1];
+};
+
+/* Comply with UEFI spec 2.1 */
+struct __packed sfi_mem_entry {
+ u32 type;
+ u64 phys_start;
+ u64 virt_start;
+ u64 pages;
+ u64 attrib;
+};
+
+struct __packed sfi_cpu_table_entry {
+ u32 apic_id;
+};
+
+struct __packed sfi_cstate_table_entry {
+ u32 hint; /* MWAIT hint */
+ u32 latency; /* latency in ms */
+};
+
+struct __packed sfi_apic_table_entry {
+ u64 phys_addr; /* phy base addr for APIC reg */
+};
+
+struct __packed sfi_freq_table_entry {
+ u32 freq_mhz; /* in MHZ */
+ u32 latency; /* transition latency in ms */
+ u32 ctrl_val; /* value to write to PERF_CTL */
+};
+
+struct __packed sfi_wake_table_entry {
+ u64 phys_addr; /* pointer to where the wake vector locates */
+};
+
+struct __packed sfi_timer_table_entry {
+ u64 phys_addr; /* phy base addr for the timer */
+ u32 freq_hz; /* in HZ */
+ u32 irq;
+};
+
+struct __packed sfi_rtc_table_entry {
+ u64 phys_addr; /* phy base addr for the RTC */
+ u32 irq;
+};
+
+struct __packed sfi_device_table_entry {
+ u8 type; /* bus type, I2C, SPI or ...*/
+ u8 host_num; /* attached to host 0, 1...*/
+ u16 addr;
+ u8 irq;
+ u32 max_freq;
+ char name[SFI_NAME_LEN];
+};
+
+enum {
+ SFI_DEV_TYPE_SPI = 0,
+ SFI_DEV_TYPE_I2C,
+ SFI_DEV_TYPE_UART,
+ SFI_DEV_TYPE_HSI,
+ SFI_DEV_TYPE_IPC,
+ SFI_DEV_TYPE_SD,
+};
+
+struct __packed sfi_gpio_table_entry {
+ char controller_name[SFI_NAME_LEN];
+ u16 pin_no;
+ char pin_name[SFI_NAME_LEN];
+};
+
+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);
+
+/**
+ * write_sfi_table() - Write Simple Firmware Interface tables
+ *
+ * @base: Address to write table to
+ * @return address to use for the next table
+ */
+u32 write_sfi_table(u32 base);
+
+#endif /*_LINUX_SFI_H */
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index 0178fe1..70ad19b 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -26,6 +26,7 @@
obj-y += relocate.o
obj-y += physmem.o
obj-$(CONFIG_X86_RAMTEST) += ramtest.o
+obj-y += sfi.o
obj-y += string.o
obj-y += tables.o
obj-$(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..3d36580
--- /dev/null
+++ b/arch/x86/lib/sfi.c
@@ -0,0 +1,154 @@
+/*
+ * 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 <asm/sfi.h>
+#include <asm/tables.h>
+#include <dm/uclass-internal.h>
+
+struct table_info {
+ u32 base;
+ int ptr;
+ u32 entry_start;
+ u64 table[SFI_TABLE_MAX_ENTRIES];
+ int count;
+};
+
+static void *get_entry_start(struct table_info *tab)
+{
+ if (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;
+
+ 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;
+ 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;
+
+ 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_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;
+}
+
+u32 write_sfi_table(u32 base)
+{
+ struct table_info table;
+
+ table.base = base;
+ table.ptr = 0;
+ table.count = 0;
+ sfi_write_cpus(&table);
+ sfi_write_apic(&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 base + table.ptr;
+}
diff --git a/arch/x86/lib/tables.c b/arch/x86/lib/tables.c
index 0836e1e..8031201 100644
--- a/arch/x86/lib/tables.c
+++ b/arch/x86/lib/tables.c
@@ -5,6 +5,7 @@
*/
#include <common.h>
+#include <asm/sfi.h>
#include <asm/tables.h>
u8 table_compute_checksum(void *v, int len)
@@ -27,4 +28,8 @@
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
}