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git01.mediatek.com / filogic / uboot / 5c549106d4d7bc767277e60a292843346ab9693c / . / arch / x86 / lib / sfi.c
blob: 3d3658088ad5b640a225125272e146aeca9c6add [file] [log] [blame]
Simon Glass07e922a2015-04-28 20:25:10 -0600[diff] [blame]1/*
2 * Copyright (c) 2015 Google, Inc
3 * Written by Simon Glass <sjg@chromium.org>
4 *
5 * SPDX-License-Identifier: GPL-2.0+
6 */
7
8/*
9 * Intel Simple Firmware Interface (SFI)
10 *
11 * Yet another way to pass information to the Linux kernel.
12 *
13 * See https://simplefirmware.org/ for details
14 */
15
16#include <common.h>
17#include <cpu.h>
18#include <dm.h>
19#include <asm/cpu.h>
20#include <asm/ioapic.h>
21#include <asm/sfi.h>
22#include <asm/tables.h>
23#include <dm/uclass-internal.h>
24
25struct table_info {
26 u32 base;
27 int ptr;
28 u32 entry_start;
29 u64 table[SFI_TABLE_MAX_ENTRIES];
30 int count;
31};
32
33static void *get_entry_start(struct table_info *tab)
34{
35 if (tab->count == SFI_TABLE_MAX_ENTRIES)
36 return NULL;
37 tab->entry_start = tab->base + tab->ptr;
38 tab->table[tab->count] = tab->entry_start;
39 tab->entry_start += sizeof(struct sfi_table_header);
40
41 return (void *)tab->entry_start;
42}
43
44static void finish_table(struct table_info *tab, const char *sig, void *entry)
45{
46 struct sfi_table_header *hdr;
47
48 hdr = (struct sfi_table_header *)(tab->base + tab->ptr);
49 strcpy(hdr->sig, sig);
50 hdr->len = sizeof(*hdr) + ((ulong)entry - tab->entry_start);
51 hdr->rev = 1;
52 strncpy(hdr->oem_id, "U-Boot", SFI_OEM_ID_SIZE);
53 strncpy(hdr->oem_table_id, "Table v1", SFI_OEM_TABLE_ID_SIZE);
54 hdr->csum = 0;
55 hdr->csum = table_compute_checksum(hdr, hdr->len);
56 tab->ptr += hdr->len;
57 tab->ptr = ALIGN(tab->ptr, 16);
58 tab->count++;
59}
60
61static int sfi_write_system_header(struct table_info *tab)
62{
63 u64 *entry = get_entry_start(tab);
64 int i;
65
66 if (!entry)
67 return -ENOSPC;
68
69 for (i = 0; i < tab->count; i++)
70 *entry++ = tab->table[i];
71 finish_table(tab, SFI_SIG_SYST, entry);
72
73 return 0;
74}
75
76static int sfi_write_cpus(struct table_info *tab)
77{
78 struct sfi_cpu_table_entry *entry = get_entry_start(tab);
79 struct udevice *dev;
80 int count = 0;
81
82 if (!entry)
83 return -ENOSPC;
84
85 for (uclass_find_first_device(UCLASS_CPU, &dev);
86 dev;
87 uclass_find_next_device(&dev)) {
88 struct cpu_platdata *plat = dev_get_parent_platdata(dev);
89
90 if (!device_active(dev))
91 continue;
92 entry->apic_id = plat->cpu_id;
93 entry++;
94 count++;
95 }
96
97 /* Omit the table if there is only one CPU */
98 if (count > 1)
99 finish_table(tab, SFI_SIG_CPUS, entry);
100
101 return 0;
102}
103
104static int sfi_write_apic(struct table_info *tab)
105{
106 struct sfi_apic_table_entry *entry = get_entry_start(tab);
107
108 if (!entry)
109 return -ENOSPC;
110
111 entry->phys_addr = IO_APIC_ADDR;
112 entry++;
113 finish_table(tab, SFI_SIG_APIC, entry);
114
115 return 0;
116}
117
118static int sfi_write_xsdt(struct table_info *tab)
119{
120 struct sfi_xsdt_header *entry = get_entry_start(tab);
121
122 if (!entry)
123 return -ENOSPC;
124
125 entry->oem_revision = 1;
126 entry->creator_id = 1;
127 entry->creator_revision = 1;
128 entry++;
129 finish_table(tab, SFI_SIG_XSDT, entry);
130
131 return 0;
132}
133
134u32 write_sfi_table(u32 base)
135{
136 struct table_info table;
137
138 table.base = base;
139 table.ptr = 0;
140 table.count = 0;
141 sfi_write_cpus(&table);
142 sfi_write_apic(&table);
143
144 /*
145 * The SFI specification marks the XSDT table as option, but Linux 4.0
146 * crashes on start-up when it is not provided.
147 */
148 sfi_write_xsdt(&table);
149
150 /* Finally, write out the system header which points to the others */
151 sfi_write_system_header(&table);
152
153 return base + table.ptr;
154}