diff --git a/drivers/mtd/nand/sunxi_nand_spl.c b/drivers/mtd/nand/sunxi_nand_spl.c index b43f2afc22..1ef7366d4c 100644 --- a/drivers/mtd/nand/sunxi_nand_spl.c +++ b/drivers/mtd/nand/sunxi_nand_spl.c @@ -103,6 +103,7 @@ struct nfc_config { int addr_cycles; int nseeds; bool randomize; + bool valid; }; /* minimal "boot0" style NAND support for Allwinner A20 */ @@ -219,6 +220,26 @@ static int nand_load_page(const struct nfc_config *conf, u32 offs) return 0; } +static int nand_reset_column(void) +{ + writel((NFC_CMD_RNDOUTSTART << NFC_RANDOM_READ_CMD1_OFFSET) | + (NFC_CMD_RNDOUT << NFC_RANDOM_READ_CMD0_OFFSET) | + (NFC_CMD_RNDOUTSTART << NFC_READ_CMD_OFFSET), + SUNXI_NFC_BASE + NFC_RCMD_SET); + writel(0, SUNXI_NFC_BASE + NFC_ADDR_LOW); + writel(NFC_SEND_CMD1 | NFC_SEND_CMD2 | NFC_RAW_CMD | + (1 << NFC_ADDR_NUM_OFFSET) | NFC_SEND_ADR | NFC_CMD_RNDOUT, + SUNXI_NFC_BASE + NFC_CMD); + + if (!check_value(SUNXI_NFC_BASE + NFC_ST, NFC_ST_CMD_INT_FLAG, + DEFAULT_TIMEOUT_US)) { + printf("Error while initializing dma interrupt\n"); + return -1; + } + + return 0; +} + static int nand_read_page(const struct nfc_config *conf, u32 offs, void *dest, int len) { @@ -303,88 +324,213 @@ static int nand_read_page(const struct nfc_config *conf, u32 offs, return (val & 0x10000) ? 1 : 0; } -static int nand_read_ecc(int page_size, int ecc_strength, int ecc_page_size, - int addr_cycles, uint32_t offs, uint32_t size, void *dest) +static int nand_max_ecc_strength(struct nfc_config *conf) { - void *end = dest + size; - static const u8 strengths[] = { 16, 24, 28, 32, 40, 48, 56, 60, 64 }; - struct nfc_config conf = { - .page_size = page_size, - .ecc_size = ecc_page_size, - .addr_cycles = addr_cycles, - .nseeds = ARRAY_SIZE(random_seed), - .randomize = true, - }; + static const int ecc_bytes[] = { 32, 46, 54, 60, 74, 88, 102, 110, 116 }; + int max_oobsize, max_ecc_bytes; + int nsectors = conf->page_size / conf->ecc_size; int i; - for (i = 0; i < ARRAY_SIZE(strengths); i++) { - if (ecc_strength == strengths[i]) { - conf.ecc_strength = i; + /* + * ECC strength is limited by the size of the OOB area which is + * correlated with the page size. + */ + switch (conf->page_size) { + case 2048: + max_oobsize = 64; + break; + case 4096: + max_oobsize = 256; + break; + case 8192: + max_oobsize = 640; + break; + case 16384: + max_oobsize = 1664; + break; + default: + return -EINVAL; + } + + max_ecc_bytes = max_oobsize / nsectors; + + for (i = 0; i < ARRAY_SIZE(ecc_bytes); i++) { + if (ecc_bytes[i] > max_ecc_bytes) break; + } + + if (!i) + return -EINVAL; + + return i - 1; +} + +static int nand_detect_ecc_config(struct nfc_config *conf, u32 offs, + void *dest) +{ + /* NAND with pages > 4k will likely require 1k sector size. */ + int min_ecc_size = conf->page_size > 4096 ? 1024 : 512; + int page = offs / conf->page_size; + int ret; + + /* + * In most cases, 1k sectors are preferred over 512b ones, start + * testing this config first. + */ + for (conf->ecc_size = 1024; conf->ecc_size >= min_ecc_size; + conf->ecc_size >>= 1) { + int max_ecc_strength = nand_max_ecc_strength(conf); + + nand_apply_config(conf); + + /* + * We are starting from the maximum ECC strength because + * most of the time NAND vendors provide an OOB area that + * barely meets the ECC requirements. + */ + for (conf->ecc_strength = max_ecc_strength; + conf->ecc_strength >= 0; + conf->ecc_strength--) { + conf->randomize = false; + if (nand_reset_column()) + return -EIO; + + /* + * Only read the first sector to speedup detection. + */ + ret = nand_read_page(conf, offs, dest, conf->ecc_size); + if (!ret) { + return 0; + } else if (ret > 0) { + /* + * If page is empty we can't deduce anything + * about the ECC config => stop the detection. + */ + return -EINVAL; + } + + conf->randomize = true; + conf->nseeds = ARRAY_SIZE(random_seed); + do { + if (nand_reset_column()) + return -EIO; + + if (!nand_read_page(conf, offs, dest, + conf->ecc_size)) + return 0; + + /* + * Find the next ->nseeds value that would + * change the randomizer seed for the page + * we're trying to read. + */ + while (conf->nseeds >= 16) { + int seed = page % conf->nseeds; + + conf->nseeds >>= 1; + if (seed != page % conf->nseeds) + break; + } + } while (conf->nseeds >= 16); } } + return -EINVAL; +} - nand_apply_config(&conf); +static int nand_detect_config(struct nfc_config *conf, u32 offs, void *dest) +{ + if (conf->valid) + return 0; - for ( ;dest < end; dest += ecc_page_size, offs += page_size) { - if (nand_load_page(&conf, offs)) + /* + * Modern NANDs are more likely than legacy ones, so we start testing + * with 5 address cycles. + */ + for (conf->addr_cycles = 5; + conf->addr_cycles >= 4; + conf->addr_cycles--) { + int max_page_size = conf->addr_cycles == 4 ? 2048 : 16384; + + /* + * Ignoring 1k pages cause I'm not even sure this case exist + * in the real world. + */ + for (conf->page_size = 2048; conf->page_size <= max_page_size; + conf->page_size <<= 1) { + if (nand_load_page(conf, offs)) + return -1; + + if (!nand_detect_ecc_config(conf, offs, dest)) { + conf->valid = true; + return 0; + } + } + } + + return -EINVAL; +} + +static int nand_read_buffer(struct nfc_config *conf, uint32_t offs, + unsigned int size, void *dest) +{ + int first_seed, page, ret; + + size = ALIGN(size, conf->page_size); + page = offs / conf->page_size; + first_seed = page % conf->nseeds; + + for (; size; size -= conf->page_size) { + if (nand_load_page(conf, offs)) return -1; - if (nand_read_page(&conf, offs, dest, page_size)) - return -1; + ret = nand_read_page(conf, offs, dest, conf->page_size); + /* + * The ->nseeds value should be equal to the number of pages + * in an eraseblock. Since we don't know this information in + * advance we might have picked a wrong value. + */ + if (ret < 0 && conf->randomize) { + int cur_seed = page % conf->nseeds; + + /* + * We already tried all the seed values => we are + * facing a real corruption. + */ + if (cur_seed < first_seed) + return -EIO; + + /* Try to adjust ->nseeds and read the page again... */ + conf->nseeds = cur_seed; + + if (nand_reset_column()) + return -EIO; + + /* ... it still fails => it's a real corruption. */ + if (nand_read_page(conf, offs, dest, conf->page_size)) + return -EIO; + } else if (ret && conf->randomize) { + memset(dest, 0xff, conf->page_size); + } + + page++; + offs += conf->page_size; + dest += conf->page_size; } return 0; } -static int nand_read_buffer(uint32_t offs, unsigned int size, void *dest) -{ - const struct { - int page_size; - int ecc_strength; - int ecc_page_size; - int addr_cycles; - } nand_configs[] = { - { 8192, 40, 1024, 5 }, - { 16384, 56, 1024, 5 }, - { 8192, 24, 1024, 5 }, - { 4096, 24, 1024, 5 }, - }; - static int nand_config = -1; - int i; - - if (nand_config == -1) { - for (i = 0; i < ARRAY_SIZE(nand_configs); i++) { - debug("nand: trying page %d ecc %d / %d addr %d: ", - nand_configs[i].page_size, - nand_configs[i].ecc_strength, - nand_configs[i].ecc_page_size, - nand_configs[i].addr_cycles); - if (nand_read_ecc(nand_configs[i].page_size, - nand_configs[i].ecc_strength, - nand_configs[i].ecc_page_size, - nand_configs[i].addr_cycles, - offs, size, dest) == 0) { - debug("success\n"); - nand_config = i; - return 0; - } - debug("failed\n"); - } - return -1; - } - - return nand_read_ecc(nand_configs[nand_config].page_size, - nand_configs[nand_config].ecc_strength, - nand_configs[nand_config].ecc_page_size, - nand_configs[nand_config].addr_cycles, - offs, size, dest); -} - int nand_spl_load_image(uint32_t offs, unsigned int size, void *dest) { - return nand_read_buffer(offs, size, dest); + static struct nfc_config conf = { }; + int ret; + + ret = nand_detect_config(&conf, offs, dest); + if (ret) + return ret; + + return nand_read_buffer(&conf, offs, size, dest); } void nand_deselect(void)