blob: 2aa7807f3e5e5bba40b84b183073ada9bb490845 [file] [log] [blame]
Mansoor Ahamed04c37572012-11-06 13:06:32 +00001/*
2 * (C) Copyright 2010-2011 Texas Instruments, <www.ti.com>
3 * Mansoor Ahamed <mansoor.ahamed@ti.com>
4 *
5 * BCH Error Location Module (ELM) support.
6 *
7 * NOTE:
8 * 1. Supports only continuous mode. Dont see need for page mode in uboot
9 * 2. Supports only syndrome polynomial 0. i.e. poly local variable is
10 * always set to ELM_DEFAULT_POLY. Dont see need for other polynomial
11 * sets in uboot
12 *
Wolfgang Denk1a459662013-07-08 09:37:19 +020013 * SPDX-License-Identifier: GPL-2.0+
Mansoor Ahamed04c37572012-11-06 13:06:32 +000014 */
15
16#include <common.h>
17#include <asm/io.h>
18#include <asm/errno.h>
19#include <asm/arch/cpu.h>
Andreas Bießmann5bf299b2013-04-02 06:05:54 +000020#include <asm/omap_gpmc.h>
pekon guptabeba5f02013-11-18 19:02:59 +053021#include <asm/omap_elm.h>
Mansoor Ahamed04c37572012-11-06 13:06:32 +000022
23#define ELM_DEFAULT_POLY (0)
24
25struct elm *elm_cfg;
26
27/**
28 * elm_load_syndromes - Load BCH syndromes based on nibble selection
29 * @syndrome: BCH syndrome
30 * @nibbles:
31 * @poly: Syndrome Polynomial set to use
32 *
33 * Load BCH syndromes based on nibble selection
34 */
35static void elm_load_syndromes(u8 *syndrome, u32 nibbles, u8 poly)
36{
37 u32 *ptr;
38 u32 val;
39
40 /* reg 0 */
41 ptr = &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[0];
42 val = syndrome[0] | (syndrome[1] << 8) | (syndrome[2] << 16) |
43 (syndrome[3] << 24);
44 writel(val, ptr);
45 /* reg 1 */
46 ptr = &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[1];
47 val = syndrome[4] | (syndrome[5] << 8) | (syndrome[6] << 16) |
48 (syndrome[7] << 24);
49 writel(val, ptr);
50
51 /* BCH 8-bit with 26 nibbles (4*8=32) */
52 if (nibbles > 13) {
53 /* reg 2 */
54 ptr = &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[2];
55 val = syndrome[8] | (syndrome[9] << 8) | (syndrome[10] << 16) |
56 (syndrome[11] << 24);
57 writel(val, ptr);
58 /* reg 3 */
59 ptr = &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[3];
60 val = syndrome[12] | (syndrome[13] << 8) |
61 (syndrome[14] << 16) | (syndrome[15] << 24);
62 writel(val, ptr);
63 }
64
65 /* BCH 16-bit with 52 nibbles (7*8=56) */
66 if (nibbles > 26) {
67 /* reg 4 */
68 ptr = &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[4];
69 val = syndrome[16] | (syndrome[17] << 8) |
70 (syndrome[18] << 16) | (syndrome[19] << 24);
71 writel(val, ptr);
72
73 /* reg 5 */
74 ptr = &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[5];
75 val = syndrome[20] | (syndrome[21] << 8) |
76 (syndrome[22] << 16) | (syndrome[23] << 24);
77 writel(val, ptr);
78
79 /* reg 6 */
80 ptr = &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[6];
81 val = syndrome[24] | (syndrome[25] << 8) |
82 (syndrome[26] << 16) | (syndrome[27] << 24);
83 writel(val, ptr);
84 }
85}
86
87/**
88 * elm_check_errors - Check for BCH errors and return error locations
89 * @syndrome: BCH syndrome
90 * @nibbles:
91 * @error_count: Returns number of errrors in the syndrome
92 * @error_locations: Returns error locations (in decimal) in this array
93 *
94 * Check the provided syndrome for BCH errors and return error count
95 * and locations in the array passed. Returns -1 if error is not correctable,
96 * else returns 0
97 */
98int elm_check_error(u8 *syndrome, u32 nibbles, u32 *error_count,
99 u32 *error_locations)
100{
101 u8 poly = ELM_DEFAULT_POLY;
102 s8 i;
103 u32 location_status;
104
105 elm_load_syndromes(syndrome, nibbles, poly);
106
107 /* start processing */
108 writel((readl(&elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[6])
109 | ELM_SYNDROME_FRAGMENT_6_SYNDROME_VALID),
110 &elm_cfg->syndrome_fragments[poly].syndrome_fragment_x[6]);
111
112 /* wait for processing to complete */
113 while ((readl(&elm_cfg->irqstatus) & (0x1 << poly)) != 0x1)
114 ;
115 /* clear status */
116 writel((readl(&elm_cfg->irqstatus) | (0x1 << poly)),
117 &elm_cfg->irqstatus);
118
119 /* check if correctable */
120 location_status = readl(&elm_cfg->error_location[poly].location_status);
121 if (!(location_status & ELM_LOCATION_STATUS_ECC_CORRECTABLE_MASK))
122 return -1;
123
124 /* get error count */
125 *error_count = readl(&elm_cfg->error_location[poly].location_status) &
126 ELM_LOCATION_STATUS_ECC_NB_ERRORS_MASK;
127
128 for (i = 0; i < *error_count; i++) {
129 error_locations[i] =
pekon guptabeba5f02013-11-18 19:02:59 +0530130 readl(&elm_cfg->error_location[poly].error_location_x[i]);
Mansoor Ahamed04c37572012-11-06 13:06:32 +0000131 }
132
133 return 0;
134}
135
136
137/**
138 * elm_config - Configure ELM module
139 * @level: 4 / 8 / 16 bit BCH
140 *
141 * Configure ELM module based on BCH level.
142 * Set mode as continuous mode.
143 * Currently we are using only syndrome 0 and syndromes 1 to 6 are not used.
144 * Also, the mode is set only for syndrome 0
145 */
146int elm_config(enum bch_level level)
147{
148 u32 val;
149 u8 poly = ELM_DEFAULT_POLY;
150 u32 buffer_size = 0x7FF;
151
152 /* config size and level */
153 val = (u32)(level) & ELM_LOCATION_CONFIG_ECC_BCH_LEVEL_MASK;
154 val |= ((buffer_size << ELM_LOCATION_CONFIG_ECC_SIZE_POS) &
155 ELM_LOCATION_CONFIG_ECC_SIZE_MASK);
156 writel(val, &elm_cfg->location_config);
157
158 /* config continous mode */
159 /* enable interrupt generation for syndrome polynomial set */
160 writel((readl(&elm_cfg->irqenable) | (0x1 << poly)),
161 &elm_cfg->irqenable);
162 /* set continuous mode for the syndrome polynomial set */
163 writel((readl(&elm_cfg->page_ctrl) & ~(0x1 << poly)),
164 &elm_cfg->page_ctrl);
165
166 return 0;
167}
168
169/**
170 * elm_reset - Do a soft reset of ELM
171 *
172 * Perform a soft reset of ELM and return after reset is done.
173 */
174void elm_reset(void)
175{
176 /* initiate reset */
177 writel((readl(&elm_cfg->sysconfig) | ELM_SYSCONFIG_SOFTRESET),
pekon guptabeba5f02013-11-18 19:02:59 +0530178 &elm_cfg->sysconfig);
Mansoor Ahamed04c37572012-11-06 13:06:32 +0000179
180 /* wait for reset complete and normal operation */
181 while ((readl(&elm_cfg->sysstatus) & ELM_SYSSTATUS_RESETDONE) !=
182 ELM_SYSSTATUS_RESETDONE)
183 ;
184}
185
186/**
187 * elm_init - Initialize ELM module
188 *
189 * Initialize ELM support. Currently it does only base address init
190 * and ELM reset.
191 */
192void elm_init(void)
193{
194 elm_cfg = (struct elm *)ELM_BASE;
195 elm_reset();
196}