blob: 0ebe72dd7f4b5c5b7c80971c67ec5f5d8651f1b7 [file] [log] [blame]
Lee Leahy32471722015-04-20 15:20:28 -07001/*
2 * This file is part of the coreboot project.
3 *
4 * Copyright (C) 2013 Google Inc.
5 * Copyright (C) 2015 Intel Corp.
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; version 2 of the License.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
Lee Leahy32471722015-04-20 15:20:28 -070015 */
16
17
18#include <arch/byteorder.h>
19#include <boot/coreboot_tables.h>
20#include <cbmem.h>
21#include <cbfs.h>
22#include <console/console.h>
23#include <stdlib.h>
24#include <string.h>
25#include <vendorcode/google/chromeos/chromeos.h>
26
27#define CACHELINE_SIZE 64
28#define INTRA_CACHELINE_MASK (CACHELINE_SIZE - 1)
29#define CACHELINE_MASK (~INTRA_CACHELINE_MASK)
30
31static void *find_mirror_buffer(int len)
32{
33 int nentries;
34 int i;
35 struct lb_memory *mem;
36 void *buffer;
37
38 len = ALIGN(len, 4096);
39
40 mem = get_lb_mem();
41 nentries = (mem->size - sizeof(*mem)) / sizeof(mem->map[0]);
42
43 /*
44 * Find the highest RAM entry that accommodates the lenth provide
45 * while falling below 4GiB.
46 */
47 buffer = NULL;
48 for (i = 0; i < nentries; i++) {
49 const uint64_t max_addr = 1ULL << 32;
50 uint64_t start;
51 uint64_t size;
52 struct lb_memory_range *r;
53
54 r = &mem->map[i];
55
56 if (r->type != LB_MEM_RAM)
57 continue;
58
59 start = unpack_lb64(r->start);
60 if (start >= max_addr)
61 continue;
62
63 size = unpack_lb64(r->size);
64 if (size < len)
65 continue;
66
67 /* Adjust size of buffer if range exceeds max address. */
68 if (start + size > max_addr)
69 size = max_addr - start;
70
71 if (size < len)
72 continue;
73
74 buffer = (void *)(uintptr_t)(start + size - len);
75 }
76
77 return buffer;
78}
79
80/*
81 * Mirror the payload file to the default SMM location if it is small enough.
82 * The default SMM region can be used since no one is using the memory at this
83 * location at this stage in the boot.
84 */
85static void *spi_mirror(void *file_start, int file_len)
86{
87 int alignment_diff;
88 char *src;
89 char *dest;
90
91 alignment_diff = (INTRA_CACHELINE_MASK & (long)file_start);
92
93 /*
94 * Adjust file length so that the start and end points are aligned to a
95 * cacheline. Coupled with the ROM caching in the CPU the SPI hardware
96 * will read and cache full length cachelines. It will also prefetch
97 * data as well. Once things are mirrored in memory all accesses should
98 * hit the CPUs cache.
99 */
100 file_len += alignment_diff;
101 file_len = ALIGN(file_len, CACHELINE_SIZE);
102
103 printk(BIOS_DEBUG, "Payload aligned size: 0x%x\n", file_len);
104
105 dest = find_mirror_buffer(file_len);
106
107 /*
108 * Just pass back the pointer to ROM space if a buffer could not
109 * be found to mirror into.
110 */
111 if (dest == NULL)
112 return file_start;
113
114 src = (void *)(CACHELINE_MASK & (long)file_start);
115 /*
116 * Note that if mempcy is not using 32-bit moves the performance will
117 * degrade because the SPI hardware prefetchers look for
118 * cacheline-aligned 32-bit accesses to kick in.
119 */
120 memcpy(dest, src, file_len);
121
122 /* Provide pointer into mirrored space. */
123 return &dest[alignment_diff];
124}
125
126void *cbfs_load_payload(struct cbfs_media *media, const char *name)
127{
128 int file_len;
129 void *file_start;
130 struct cbfs_file *file;
131
132 file_start = vboot_get_payload(&file_len);
133
134 if (file_start != NULL)
135 return spi_mirror(file_start, file_len);
136
137 file = cbfs_get_file(media, name);
138
139 if (file == NULL)
140 return NULL;
141
142 if (ntohl(file->type) != CBFS_TYPE_PAYLOAD)
143 return NULL;
144
145 file_len = ntohl(file->len);
146
147 file_start = CBFS_SUBHEADER(file);
148
149 return spi_mirror(file_start, file_len);
150}