summaryrefslogtreecommitdiff
path: root/chip/host/flash.c
blob: fac8620b381a79844b3fd5569d05a9f1d0c6ae06 (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
/* Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

/* Flash module for emulator */

#include <stdio.h>

#include "common.h"
#include "flash.h"
#include "persistence.h"
#include "util.h"

char __host_flash[CONFIG_FLASH_PHYSICAL_SIZE];
uint8_t __host_flash_protect[PHYSICAL_BANKS];

static int flash_check_protect(int offset, int size)
{
	int first_bank = offset / CONFIG_FLASH_BANK_SIZE;
	int last_bank = DIV_ROUND_UP(offset + size + 1,
				     CONFIG_FLASH_BANK_SIZE);
	int bank;

	for (bank = first_bank; bank <= last_bank; ++bank)
		if (__host_flash_protect[bank])
			return 1;
	return 0;
}

static void flash_set_persistent(void)
{
	FILE *f = get_persistent_storage("flash", "wb");
	int sz;

	ASSERT(f != NULL);

	sz = fwrite(__host_flash, sizeof(__host_flash), 1, f);
	ASSERT(sz == 1);

	release_persistent_storage(f);
}

static void flash_get_persistent(void)
{
	FILE *f = get_persistent_storage("flash", "rb");

	if (f == NULL) {
		fprintf(stderr,
			"No flash storage found. Initializing to 0xff.\n");
		memset(__host_flash, 0xff, sizeof(__host_flash));
		return;
	}

	fread(__host_flash, sizeof(__host_flash), 1, f);

	release_persistent_storage(f);
}

int flash_physical_write(int offset, int size, const char *data)
{
	ASSERT((size & (CONFIG_FLASH_WRITE_SIZE - 1)) == 0);

	if (flash_check_protect(offset, size))
		return EC_ERROR_ACCESS_DENIED;

	memcpy(__host_flash + offset, data, size);
	flash_set_persistent();

	return EC_SUCCESS;
}

int flash_physical_erase(int offset, int size)
{
	ASSERT((size & (CONFIG_FLASH_ERASE_SIZE - 1)) == 0);

	if (flash_check_protect(offset, size))
		return EC_ERROR_ACCESS_DENIED;

	memset(__host_flash + offset, 0xff, size);
	flash_set_persistent();

	return EC_SUCCESS;
}

int flash_physical_get_protect(int bank)
{
	return __host_flash_protect[bank];
}

uint32_t flash_physical_get_protect_flags(void)
{
	int i;
	uint32_t flags = EC_FLASH_PROTECT_ALL_NOW;

	for (i = 0; i < PHYSICAL_BANKS; ++i)
		if (__host_flash_protect[i] == 0)
			flags = 0;

	return flags;
}

int flash_physical_protect_now(int all)
{
	memset(__host_flash_protect, 1, all ? PHYSICAL_BANKS : RO_BANK_COUNT);
	return EC_SUCCESS;
}

int flash_pre_init(void)
{
	uint32_t prot_flags;

	flash_get_persistent();

	prot_flags = flash_get_protect();

	if (prot_flags & EC_FLASH_PROTECT_GPIO_ASSERTED) {
		/*
		 * Write protect is asserted.  If we want RO flash protected,
		 * protect it now.
		 */
		if ((prot_flags & EC_FLASH_PROTECT_RO_AT_BOOT) &&
		    !(prot_flags & EC_FLASH_PROTECT_RO_NOW)) {
			int rv = flash_set_protect(EC_FLASH_PROTECT_RO_NOW,
						   EC_FLASH_PROTECT_RO_NOW);
			if (rv)
				return rv;

			/* Re-read flags */
			prot_flags = flash_get_protect();
		}
	}

	return EC_SUCCESS;
}