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>

1 files changed, 137 insertions, 0 deletions

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 */