Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2012 Google, Inc. |
| 3 | * |
| 4 | * This software is licensed under the terms of the GNU General Public |
| 5 | * License version 2, as published by the Free Software Foundation, and |
| 6 | * may be copied, distributed, and modified under those terms. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 11 | * GNU General Public License for more details. |
| 12 | * |
| 13 | */ |
| 14 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 15 | #include <linux/device.h> |
| 16 | #include <linux/err.h> |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 17 | #include <linux/errno.h> |
| 18 | #include <linux/kernel.h> |
| 19 | #include <linux/init.h> |
| 20 | #include <linux/io.h> |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 21 | #include <linux/list.h> |
| 22 | #include <linux/memblock.h> |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 23 | #include <linux/rslib.h> |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 24 | #include <linux/slab.h> |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 25 | #include <linux/vmalloc.h> |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 26 | #include "persistent_ram.h" |
| 27 | |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 28 | struct persistent_ram_buffer { |
| 29 | uint32_t sig; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 30 | atomic_t start; |
| 31 | atomic_t size; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 32 | uint8_t data[0]; |
| 33 | }; |
| 34 | |
| 35 | #define PERSISTENT_RAM_SIG (0x43474244) /* DBGC */ |
| 36 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 37 | static __initdata LIST_HEAD(persistent_ram_list); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 38 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 39 | static inline size_t buffer_size(struct persistent_ram_zone *prz) |
| 40 | { |
| 41 | return atomic_read(&prz->buffer->size); |
| 42 | } |
| 43 | |
| 44 | static inline size_t buffer_start(struct persistent_ram_zone *prz) |
| 45 | { |
| 46 | return atomic_read(&prz->buffer->start); |
| 47 | } |
| 48 | |
| 49 | /* increase and wrap the start pointer, returning the old value */ |
| 50 | static inline size_t buffer_start_add(struct persistent_ram_zone *prz, size_t a) |
| 51 | { |
| 52 | int old; |
| 53 | int new; |
| 54 | |
| 55 | do { |
| 56 | old = atomic_read(&prz->buffer->start); |
| 57 | new = old + a; |
| 58 | while (unlikely(new > prz->buffer_size)) |
| 59 | new -= prz->buffer_size; |
| 60 | } while (atomic_cmpxchg(&prz->buffer->start, old, new) != old); |
| 61 | |
| 62 | return old; |
| 63 | } |
| 64 | |
| 65 | /* increase the size counter until it hits the max size */ |
| 66 | static inline void buffer_size_add(struct persistent_ram_zone *prz, size_t a) |
| 67 | { |
| 68 | size_t old; |
| 69 | size_t new; |
| 70 | |
| 71 | if (atomic_read(&prz->buffer->size) == prz->buffer_size) |
| 72 | return; |
| 73 | |
| 74 | do { |
| 75 | old = atomic_read(&prz->buffer->size); |
| 76 | new = old + a; |
| 77 | if (new > prz->buffer_size) |
| 78 | new = prz->buffer_size; |
| 79 | } while (atomic_cmpxchg(&prz->buffer->size, old, new) != old); |
| 80 | } |
| 81 | |
| 82 | /* increase the size counter, retuning an error if it hits the max size */ |
| 83 | static inline ssize_t buffer_size_add_clamp(struct persistent_ram_zone *prz, |
| 84 | size_t a) |
| 85 | { |
| 86 | size_t old; |
| 87 | size_t new; |
| 88 | |
| 89 | do { |
| 90 | old = atomic_read(&prz->buffer->size); |
| 91 | new = old + a; |
| 92 | if (new > prz->buffer_size) |
| 93 | return -ENOMEM; |
| 94 | } while (atomic_cmpxchg(&prz->buffer->size, old, new) != old); |
| 95 | |
| 96 | return 0; |
| 97 | } |
| 98 | |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 99 | static void persistent_ram_encode_rs8(struct persistent_ram_zone *prz, |
| 100 | uint8_t *data, size_t len, uint8_t *ecc) |
| 101 | { |
| 102 | int i; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 103 | uint16_t par[prz->ecc_size]; |
| 104 | |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 105 | /* Initialize the parity buffer */ |
| 106 | memset(par, 0, sizeof(par)); |
| 107 | encode_rs8(prz->rs_decoder, data, len, par, 0); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 108 | for (i = 0; i < prz->ecc_size; i++) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 109 | ecc[i] = par[i]; |
| 110 | } |
| 111 | |
| 112 | static int persistent_ram_decode_rs8(struct persistent_ram_zone *prz, |
| 113 | void *data, size_t len, uint8_t *ecc) |
| 114 | { |
| 115 | int i; |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 116 | uint16_t par[prz->ecc_size]; |
| 117 | |
| 118 | for (i = 0; i < prz->ecc_size; i++) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 119 | par[i] = ecc[i]; |
| 120 | return decode_rs8(prz->rs_decoder, data, par, len, |
| 121 | NULL, 0, NULL, 0, NULL); |
| 122 | } |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 123 | |
| 124 | static void persistent_ram_update_ecc(struct persistent_ram_zone *prz, |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 125 | unsigned int start, unsigned int count) |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 126 | { |
| 127 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 128 | uint8_t *buffer_end = buffer->data + prz->buffer_size; |
| 129 | uint8_t *block; |
| 130 | uint8_t *par; |
| 131 | int ecc_block_size = prz->ecc_block_size; |
| 132 | int ecc_size = prz->ecc_size; |
| 133 | int size = prz->ecc_block_size; |
| 134 | |
| 135 | if (!prz->ecc) |
| 136 | return; |
| 137 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 138 | block = buffer->data + (start & ~(ecc_block_size - 1)); |
| 139 | par = prz->par_buffer + (start / ecc_block_size) * prz->ecc_size; |
| 140 | |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 141 | do { |
| 142 | if (block + ecc_block_size > buffer_end) |
| 143 | size = buffer_end - block; |
| 144 | persistent_ram_encode_rs8(prz, block, size, par); |
| 145 | block += ecc_block_size; |
| 146 | par += ecc_size; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 147 | } while (block < buffer->data + start + count); |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 148 | } |
| 149 | |
| 150 | static void persistent_ram_update_header_ecc(struct persistent_ram_zone *prz) |
| 151 | { |
| 152 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 153 | |
| 154 | if (!prz->ecc) |
| 155 | return; |
| 156 | |
| 157 | persistent_ram_encode_rs8(prz, (uint8_t *)buffer, sizeof(*buffer), |
| 158 | prz->par_header); |
| 159 | } |
| 160 | |
| 161 | static void persistent_ram_ecc_old(struct persistent_ram_zone *prz) |
| 162 | { |
| 163 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 164 | uint8_t *block; |
| 165 | uint8_t *par; |
| 166 | |
| 167 | if (!prz->ecc) |
| 168 | return; |
| 169 | |
| 170 | block = buffer->data; |
| 171 | par = prz->par_buffer; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 172 | while (block < buffer->data + buffer_size(prz)) { |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 173 | int numerr; |
| 174 | int size = prz->ecc_block_size; |
| 175 | if (block + size > buffer->data + prz->buffer_size) |
| 176 | size = buffer->data + prz->buffer_size - block; |
| 177 | numerr = persistent_ram_decode_rs8(prz, block, size, par); |
| 178 | if (numerr > 0) { |
| 179 | pr_devel("persistent_ram: error in block %p, %d\n", |
| 180 | block, numerr); |
| 181 | prz->corrected_bytes += numerr; |
| 182 | } else if (numerr < 0) { |
| 183 | pr_devel("persistent_ram: uncorrectable error in block %p\n", |
| 184 | block); |
| 185 | prz->bad_blocks++; |
| 186 | } |
| 187 | block += prz->ecc_block_size; |
| 188 | par += prz->ecc_size; |
| 189 | } |
| 190 | } |
| 191 | |
| 192 | static int persistent_ram_init_ecc(struct persistent_ram_zone *prz, |
| 193 | size_t buffer_size) |
| 194 | { |
| 195 | int numerr; |
| 196 | struct persistent_ram_buffer *buffer = prz->buffer; |
| 197 | int ecc_blocks; |
| 198 | |
| 199 | if (!prz->ecc) |
| 200 | return 0; |
| 201 | |
| 202 | prz->ecc_block_size = 128; |
| 203 | prz->ecc_size = 16; |
| 204 | prz->ecc_symsize = 8; |
| 205 | prz->ecc_poly = 0x11d; |
| 206 | |
| 207 | ecc_blocks = DIV_ROUND_UP(prz->buffer_size, prz->ecc_block_size); |
| 208 | prz->buffer_size -= (ecc_blocks + 1) * prz->ecc_size; |
| 209 | |
| 210 | if (prz->buffer_size > buffer_size) { |
| 211 | pr_err("persistent_ram: invalid size %zu, non-ecc datasize %zu\n", |
| 212 | buffer_size, prz->buffer_size); |
| 213 | return -EINVAL; |
| 214 | } |
| 215 | |
| 216 | prz->par_buffer = buffer->data + prz->buffer_size; |
| 217 | prz->par_header = prz->par_buffer + ecc_blocks * prz->ecc_size; |
| 218 | |
| 219 | /* |
| 220 | * first consecutive root is 0 |
| 221 | * primitive element to generate roots = 1 |
| 222 | */ |
| 223 | prz->rs_decoder = init_rs(prz->ecc_symsize, prz->ecc_poly, 0, 1, |
| 224 | prz->ecc_size); |
| 225 | if (prz->rs_decoder == NULL) { |
| 226 | pr_info("persistent_ram: init_rs failed\n"); |
| 227 | return -EINVAL; |
| 228 | } |
| 229 | |
| 230 | prz->corrected_bytes = 0; |
| 231 | prz->bad_blocks = 0; |
| 232 | |
| 233 | numerr = persistent_ram_decode_rs8(prz, buffer, sizeof(*buffer), |
| 234 | prz->par_header); |
| 235 | if (numerr > 0) { |
| 236 | pr_info("persistent_ram: error in header, %d\n", numerr); |
| 237 | prz->corrected_bytes += numerr; |
| 238 | } else if (numerr < 0) { |
| 239 | pr_info("persistent_ram: uncorrectable error in header\n"); |
| 240 | prz->bad_blocks++; |
| 241 | } |
| 242 | |
| 243 | return 0; |
| 244 | } |
| 245 | |
| 246 | ssize_t persistent_ram_ecc_string(struct persistent_ram_zone *prz, |
| 247 | char *str, size_t len) |
| 248 | { |
| 249 | ssize_t ret; |
| 250 | |
| 251 | if (prz->corrected_bytes || prz->bad_blocks) |
| 252 | ret = snprintf(str, len, "" |
| 253 | "\n%d Corrected bytes, %d unrecoverable blocks\n", |
| 254 | prz->corrected_bytes, prz->bad_blocks); |
| 255 | else |
| 256 | ret = snprintf(str, len, "\nNo errors detected\n"); |
| 257 | |
| 258 | return ret; |
| 259 | } |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 260 | |
| 261 | static void persistent_ram_update(struct persistent_ram_zone *prz, |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 262 | const void *s, unsigned int start, unsigned int count) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 263 | { |
| 264 | struct persistent_ram_buffer *buffer = prz->buffer; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 265 | memcpy(buffer->data + start, s, count); |
| 266 | persistent_ram_update_ecc(prz, start, count); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 267 | } |
| 268 | |
| 269 | static void __init |
| 270 | persistent_ram_save_old(struct persistent_ram_zone *prz) |
| 271 | { |
| 272 | struct persistent_ram_buffer *buffer = prz->buffer; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 273 | size_t size = buffer_size(prz); |
| 274 | size_t start = buffer_start(prz); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 275 | char *dest; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 276 | |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 277 | persistent_ram_ecc_old(prz); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 278 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 279 | dest = kmalloc(size, GFP_KERNEL); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 280 | if (dest == NULL) { |
| 281 | pr_err("persistent_ram: failed to allocate buffer\n"); |
| 282 | return; |
| 283 | } |
| 284 | |
| 285 | prz->old_log = dest; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 286 | prz->old_log_size = size; |
| 287 | memcpy(prz->old_log, &buffer->data[start], size - start); |
| 288 | memcpy(prz->old_log + size - start, &buffer->data[0], start); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 289 | } |
| 290 | |
| 291 | int persistent_ram_write(struct persistent_ram_zone *prz, |
| 292 | const void *s, unsigned int count) |
| 293 | { |
| 294 | int rem; |
| 295 | int c = count; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 296 | size_t start; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 297 | |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 298 | if (unlikely(c > prz->buffer_size)) { |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 299 | s += c - prz->buffer_size; |
| 300 | c = prz->buffer_size; |
| 301 | } |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 302 | |
| 303 | buffer_size_add_clamp(prz, c); |
| 304 | |
| 305 | start = buffer_start_add(prz, c); |
| 306 | |
| 307 | rem = prz->buffer_size - start; |
| 308 | if (unlikely(rem < c)) { |
| 309 | persistent_ram_update(prz, s, start, rem); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 310 | s += rem; |
| 311 | c -= rem; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 312 | start = 0; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 313 | } |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 314 | persistent_ram_update(prz, s, start, c); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 315 | |
Colin Cross | 9cc05ad | 2012-03-07 17:34:33 -0800 | [diff] [blame] | 316 | persistent_ram_update_header_ecc(prz); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 317 | |
| 318 | return count; |
| 319 | } |
| 320 | |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 321 | size_t persistent_ram_old_size(struct persistent_ram_zone *prz) |
| 322 | { |
| 323 | return prz->old_log_size; |
| 324 | } |
| 325 | |
| 326 | void *persistent_ram_old(struct persistent_ram_zone *prz) |
| 327 | { |
| 328 | return prz->old_log; |
| 329 | } |
| 330 | |
| 331 | void persistent_ram_free_old(struct persistent_ram_zone *prz) |
| 332 | { |
| 333 | kfree(prz->old_log); |
| 334 | prz->old_log = NULL; |
| 335 | prz->old_log_size = 0; |
| 336 | } |
| 337 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 338 | static int persistent_ram_buffer_map(phys_addr_t start, phys_addr_t size, |
| 339 | struct persistent_ram_zone *prz) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 340 | { |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 341 | struct page **pages; |
| 342 | phys_addr_t page_start; |
| 343 | unsigned int page_count; |
| 344 | pgprot_t prot; |
| 345 | unsigned int i; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 346 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 347 | page_start = start - offset_in_page(start); |
| 348 | page_count = DIV_ROUND_UP(size + offset_in_page(start), PAGE_SIZE); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 349 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 350 | prot = pgprot_noncached(PAGE_KERNEL); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 351 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 352 | pages = kmalloc(sizeof(struct page *) * page_count, GFP_KERNEL); |
| 353 | if (!pages) { |
| 354 | pr_err("%s: Failed to allocate array for %u pages\n", __func__, |
| 355 | page_count); |
| 356 | return -ENOMEM; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 357 | } |
| 358 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 359 | for (i = 0; i < page_count; i++) { |
| 360 | phys_addr_t addr = page_start + i * PAGE_SIZE; |
| 361 | pages[i] = pfn_to_page(addr >> PAGE_SHIFT); |
| 362 | } |
| 363 | prz->vaddr = vmap(pages, page_count, VM_MAP, prot); |
| 364 | kfree(pages); |
| 365 | if (!prz->vaddr) { |
| 366 | pr_err("%s: Failed to map %u pages\n", __func__, page_count); |
| 367 | return -ENOMEM; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 368 | } |
| 369 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 370 | prz->buffer = prz->vaddr + offset_in_page(start); |
| 371 | prz->buffer_size = size - sizeof(struct persistent_ram_buffer); |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 372 | |
| 373 | return 0; |
| 374 | } |
| 375 | |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 376 | static int __init persistent_ram_buffer_init(const char *name, |
| 377 | struct persistent_ram_zone *prz) |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 378 | { |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 379 | int i; |
| 380 | struct persistent_ram *ram; |
| 381 | struct persistent_ram_descriptor *desc; |
| 382 | phys_addr_t start; |
| 383 | |
| 384 | list_for_each_entry(ram, &persistent_ram_list, node) { |
| 385 | start = ram->start; |
| 386 | for (i = 0; i < ram->num_descs; i++) { |
| 387 | desc = &ram->descs[i]; |
| 388 | if (!strcmp(desc->name, name)) |
| 389 | return persistent_ram_buffer_map(start, |
| 390 | desc->size, prz); |
| 391 | start += desc->size; |
| 392 | } |
| 393 | } |
| 394 | |
| 395 | return -EINVAL; |
| 396 | } |
| 397 | |
| 398 | static __init |
| 399 | struct persistent_ram_zone *__persistent_ram_init(struct device *dev, bool ecc) |
| 400 | { |
| 401 | struct persistent_ram_zone *prz; |
| 402 | int ret; |
| 403 | |
| 404 | prz = kzalloc(sizeof(struct persistent_ram_zone), GFP_KERNEL); |
| 405 | if (!prz) { |
| 406 | pr_err("persistent_ram: failed to allocate persistent ram zone\n"); |
| 407 | return ERR_PTR(-ENOMEM); |
| 408 | } |
| 409 | |
| 410 | INIT_LIST_HEAD(&prz->node); |
| 411 | |
| 412 | ret = persistent_ram_buffer_init(dev_name(dev), prz); |
| 413 | if (ret) { |
| 414 | pr_err("persistent_ram: failed to initialize buffer\n"); |
| 415 | return ERR_PTR(ret); |
| 416 | } |
| 417 | |
| 418 | prz->ecc = ecc; |
| 419 | ret = persistent_ram_init_ecc(prz, prz->buffer_size); |
| 420 | if (ret) |
| 421 | return ERR_PTR(ret); |
| 422 | |
| 423 | if (prz->buffer->sig == PERSISTENT_RAM_SIG) { |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 424 | if (buffer_size(prz) > prz->buffer_size || |
| 425 | buffer_start(prz) > buffer_size(prz)) |
| 426 | pr_info("persistent_ram: found existing invalid buffer," |
| 427 | " size %ld, start %ld\n", |
| 428 | buffer_size(prz), buffer_start(prz)); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 429 | else { |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 430 | pr_info("persistent_ram: found existing buffer," |
| 431 | " size %ld, start %ld\n", |
| 432 | buffer_size(prz), buffer_start(prz)); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 433 | persistent_ram_save_old(prz); |
| 434 | } |
| 435 | } else { |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 436 | pr_info("persistent_ram: no valid data in buffer" |
| 437 | " (sig = 0x%08x)\n", prz->buffer->sig); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 438 | } |
| 439 | |
| 440 | prz->buffer->sig = PERSISTENT_RAM_SIG; |
Colin Cross | 808d038 | 2012-03-07 17:34:35 -0800 | [diff] [blame^] | 441 | atomic_set(&prz->buffer->start, 0); |
| 442 | atomic_set(&prz->buffer->size, 0); |
Colin Cross | 404a604 | 2012-03-07 17:34:34 -0800 | [diff] [blame] | 443 | |
| 444 | return prz; |
| 445 | } |
| 446 | |
| 447 | struct persistent_ram_zone * __init |
| 448 | persistent_ram_init_ringbuffer(struct device *dev, bool ecc) |
| 449 | { |
| 450 | return __persistent_ram_init(dev, ecc); |
| 451 | } |
| 452 | |
| 453 | int __init persistent_ram_early_init(struct persistent_ram *ram) |
| 454 | { |
| 455 | int ret; |
| 456 | |
| 457 | ret = memblock_reserve(ram->start, ram->size); |
| 458 | if (ret) { |
| 459 | pr_err("Failed to reserve persistent memory from %08lx-%08lx\n", |
| 460 | (long)ram->start, (long)(ram->start + ram->size - 1)); |
| 461 | return ret; |
| 462 | } |
| 463 | |
| 464 | list_add_tail(&ram->node, &persistent_ram_list); |
| 465 | |
| 466 | pr_info("Initialized persistent memory from %08lx-%08lx\n", |
| 467 | (long)ram->start, (long)(ram->start + ram->size - 1)); |
| 468 | |
| 469 | return 0; |
Colin Cross | c672528 | 2012-03-07 17:34:32 -0800 | [diff] [blame] | 470 | } |