aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/cpu/tangier/sdram.c
blob: f5f412a1e57ca48fbe5517165ddf0ecb57f46259 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
/*
 * Copyright (c) 2017 Intel Corporation
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <asm/e820.h>
#include <asm/global_data.h>
#include <asm/sfi.h>

DECLARE_GLOBAL_DATA_PTR;

/*
 * SFI tables are part of the first stage bootloader.
 *
 * U-Boot finds the System Table by searching 16-byte boundaries between
 * physical address 0x000E0000 and 0x000FFFFF. U-Boot shall search this region
 * starting at the low address and shall stop searching when the 1st valid SFI
 * System Table is found.
 */
#define SFI_BASE_ADDR		0x000E0000
#define SFI_LENGTH		0x00020000
#define SFI_TABLE_LENGTH	16

static int sfi_table_check(struct sfi_table_header *sbh)
{
	char chksum = 0;
	char *pos = (char *)sbh;
	u32 i;

	if (sbh->len < SFI_TABLE_LENGTH)
		return -ENXIO;

	if (sbh->len > SFI_LENGTH)
		return -ENXIO;

	for (i = 0; i < sbh->len; i++)
		chksum += *pos++;

	if (chksum)
		pr_err("sfi: Invalid checksum\n");

	/* Checksum is OK if zero */
	return chksum ? -EILSEQ : 0;
}

static int sfi_table_is_type(struct sfi_table_header *sbh, const char *signature)
{
	return !strncmp(sbh->sig, signature, SFI_SIGNATURE_SIZE) &&
	       !sfi_table_check(sbh);
}

static struct sfi_table_simple *sfi_get_table_by_sig(unsigned long addr,
						     const char *signature)
{
	struct sfi_table_simple *sb;
	u32 i;

	for (i = 0; i < SFI_LENGTH; i += SFI_TABLE_LENGTH) {
		sb = (struct sfi_table_simple *)(addr + i);
		if (sfi_table_is_type(&sb->header, signature))
			return sb;
	}

	return NULL;
}

static struct sfi_table_simple *sfi_search_mmap(void)
{
	struct sfi_table_header *sbh;
	struct sfi_table_simple *sb;
	u32 sys_entry_cnt;
	u32 i;

	/* Find SYST table */
	sb = sfi_get_table_by_sig(SFI_BASE_ADDR, SFI_SIG_SYST);
	if (!sb) {
		pr_err("sfi: failed to locate SYST table\n");
		return NULL;
	}

	sys_entry_cnt = (sb->header.len - sizeof(*sbh)) / 8;

	/* Search through each SYST entry for MMAP table */
	for (i = 0; i < sys_entry_cnt; i++) {
		sbh = (struct sfi_table_header *)(unsigned long)sb->pentry[i];

		if (sfi_table_is_type(sbh, SFI_SIG_MMAP))
			return (struct sfi_table_simple *)sbh;
	}

	pr_err("sfi: failed to locate SFI MMAP table\n");
	return NULL;
}

#define sfi_for_each_mentry(i, sb, mentry)				\
	for (i = 0, mentry = (struct sfi_mem_entry *)sb->pentry;	\
	     i < SFI_GET_NUM_ENTRIES(sb, struct sfi_mem_entry);		\
	     i++, mentry++)						\

static unsigned int sfi_setup_e820(unsigned int max_entries,
				   struct e820_entry *entries)
{
	struct sfi_table_simple *sb;
	struct sfi_mem_entry *mentry;
	unsigned long long start, end, size;
	int type, total = 0;
	u32 i;

	sb = sfi_search_mmap();
	if (!sb)
		return 0;

	sfi_for_each_mentry(i, sb, mentry) {
		start = mentry->phys_start;
		size = mentry->pages << 12;
		end = start + size;

		if (start > end)
			continue;

		/* translate SFI mmap type to E820 map type */
		switch (mentry->type) {
		case SFI_MEM_CONV:
			type = E820_RAM;
			break;
		case SFI_MEM_UNUSABLE:
		case SFI_RUNTIME_SERVICE_DATA:
			continue;
		default:
			type = E820_RESERVED;
		}

		if (total == E820MAX)
			break;
		entries[total].addr = start;
		entries[total].size = size;
		entries[total].type = type;

		total++;
	}

	return total;
}

static int sfi_get_bank_size(void)
{
	struct sfi_table_simple *sb;
	struct sfi_mem_entry *mentry;
	int bank = 0;
	u32 i;

	sb = sfi_search_mmap();
	if (!sb)
		return 0;

	sfi_for_each_mentry(i, sb, mentry) {
		if (mentry->type != SFI_MEM_CONV)
			continue;

		gd->bd->bi_dram[bank].start = mentry->phys_start;
		gd->bd->bi_dram[bank].size = mentry->pages << 12;
		bank++;
	}

	return bank;
}

static phys_size_t sfi_get_ram_size(void)
{
	struct sfi_table_simple *sb;
	struct sfi_mem_entry *mentry;
	phys_size_t ram = 0;
	u32 i;

	sb = sfi_search_mmap();
	if (!sb)
		return 0;

	sfi_for_each_mentry(i, sb, mentry) {
		if (mentry->type != SFI_MEM_CONV)
			continue;

		ram += mentry->pages << 12;
	}

	debug("sfi: RAM size %llu\n", ram);
	return ram;
}

unsigned int install_e820_map(unsigned int max_entries,
			      struct e820_entry *entries)
{
	return sfi_setup_e820(max_entries, entries);
}

int dram_init_banksize(void)
{
	sfi_get_bank_size();
	return 0;
}

int dram_init(void)
{
	gd->ram_size = sfi_get_ram_size();
	return 0;
}