blob: 140083734d8863ff4284ce62e4b6314f921383d7 [file] [log] [blame]
Martin Rothbf6b83a2015-10-11 10:37:02 +02001/*
2 * This file is part of the coreboot project.
3 *
4 * Copyright (C) 2012 Google Inc. All rights reserved.
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation; version 2 of
9 * 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.
Martin Rothbf6b83a2015-10-11 10:37:02 +020015 */
16
17#include <arch/io.h>
18#include <console/console.h>
19#include <device/pci_ids.h>
20#include <device/pci_def.h>
21#include <delay.h>
22#include "pch.h"
23
24#define SPI_DELAY 10 /* 10us */
25#define SPI_RETRY 200000 /* 2s */
26
27static int early_spi_read_block(u32 offset, u8 size, u8 *buffer)
28{
29 u32 *ptr32 = (u32*)buffer;
30 u32 i;
31
32 /* Clear status bits */
33 RCBA16(SPIBAR_HSFS) |= SPIBAR_HSFS_AEL | SPIBAR_HSFS_FCERR |
34 SPIBAR_HSFS_FDONE;
35
36 if (RCBA16(SPIBAR_HSFS) & SPIBAR_HSFS_SCIP) {
37 printk(BIOS_ERR, "SPI ERROR: transaction in progress\n");
38 return -1;
39 }
40
41 /* Set flash address */
42 RCBA32(SPIBAR_FADDR) = offset;
43
44 /* Setup read transaction */
45 RCBA16(SPIBAR_HSFC) = SPIBAR_HSFC_BYTE_COUNT(size) |
46 SPIBAR_HSFC_CYCLE_READ;
47
48 /* Start transactinon */
49 RCBA16(SPIBAR_HSFC) |= SPIBAR_HSFC_GO;
50
51 /* Wait for completion */
52 for (i = 0; i < SPI_RETRY; i++) {
53 if (RCBA16(SPIBAR_HSFS) & SPIBAR_HSFS_SCIP) {
54 /* Cycle in progress, wait 1ms */
55 udelay(SPI_DELAY);
56 continue;
57 }
58
59 if (RCBA16(SPIBAR_HSFS) & SPIBAR_HSFS_AEL) {
60 printk(BIOS_ERR, "SPI ERROR: Access Error\n");
61 return -1;
62
63 }
64
65 if (RCBA16(SPIBAR_HSFS) & SPIBAR_HSFS_FCERR) {
66 printk(BIOS_ERR, "SPI ERROR: Flash Cycle Error\n");
67 return -1;
68 }
69 break;
70 }
71
72 if (i >= SPI_RETRY) {
73 printk(BIOS_ERR, "SPI ERROR: Timeout\n");
74 return -1;
75 }
76
77 /* Read the data */
78 for (i = 0; i < size; i+=sizeof(u32)) {
79 if (size-i >= 4) {
80 /* reading >= dword */
81 *ptr32++ = RCBA32(SPIBAR_FDATA(i/sizeof(u32)));
82 } else {
83 /* reading < dword */
84 u8 j, *ptr8 = (u8*)ptr32;
85 u32 temp = RCBA32(SPIBAR_FDATA(i/sizeof(u32)));
86 for (j = 0; j < (size-i); j++) {
87 *ptr8++ = temp & 0xff;
88 temp >>= 8;
89 }
90 }
91 }
92
93 return size;
94}
95
96int early_spi_read(u32 offset, u32 size, u8 *buffer)
97{
98 u32 current = 0;
99
100 while (size > 0) {
101 u8 count = (size < 64) ? size : 64;
102 if (early_spi_read_block(offset + current, count,
103 buffer + current) < 0)
104 return -1;
105 size -= count;
106 current += count;
107 }
108
109 return 0;
110}