Helper function for bch_mtd_read() and bch_mtd_write() to handle multi-page or non-aligned reads and writes respectively.
Signed-off-by: Lee Jones <[email protected]> --- drivers/mtd/nand/stm_nand_bch.c | 143 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 143 insertions(+) diff --git a/drivers/mtd/nand/stm_nand_bch.c b/drivers/mtd/nand/stm_nand_bch.c index 389ccee..bcaed32 100644 --- a/drivers/mtd/nand/stm_nand_bch.c +++ b/drivers/mtd/nand/stm_nand_bch.c @@ -507,6 +507,149 @@ static uint8_t bch_write_page(struct nandi_controller *nandi, return status; } +/* Helper function for bch_mtd_read to handle multi-page or non-aligned reads */ +static int bch_read(struct nandi_controller *nandi, + loff_t from, size_t len, + size_t *retlen, u_char *buf) +{ + struct mtd_ecc_stats stats; + uint32_t page_size = nandi->info.mtd.writesize; + uint32_t col_offs; + loff_t page_mask; + loff_t page_offs; + int ecc_errs, max_ecc_errs = 0; + int page_num; + size_t bytes; + uint8_t *p; + bool bounce = false; + + dev_dbg(nandi->dev, "%s: %llu @ 0x%012llx\n", __func__, + (unsigned long long)len, from); + + stats = nandi->info.mtd.ecc_stats; + page_mask = (loff_t)page_size - 1; + col_offs = (uint32_t)(from & page_mask); + page_offs = from & ~page_mask; + page_num = (int)(page_offs >> nandi->page_shift); + + while (len > 0) { + bytes = min((page_size - col_offs), len); + + if ((bytes != page_size) || + ((unsigned int)buf & (NANDI_BCH_DMA_ALIGNMENT - 1)) || + (!virt_addr_valid(buf))) /* vmalloc'd buffer! */ + bounce = true; + + if (page_num == nandi->cached_page) { + memcpy(buf, nandi->page_buf + col_offs, bytes); + goto done; + } + + p = bounce ? nandi->page_buf : buf; + + ecc_errs = bch_read_page(nandi, page_offs, p); + if (bounce) + memcpy(buf, p + col_offs, bytes); + + if (ecc_errs < 0) { + dev_err(nandi->dev, + "%s: uncorrectable error at 0x%012llx\n", + __func__, page_offs); + nandi->info.mtd.ecc_stats.failed++; + + /* Do not cache uncorrectable pages */ + if (bounce) + nandi->cached_page = -1; + + goto done; + } + + if (ecc_errs) { + dev_info(nandi->dev, + "%s: corrected %u error(s) at 0x%012llx\n", + __func__, ecc_errs, page_offs); + + nandi->info.mtd.ecc_stats.corrected += ecc_errs; + + if (ecc_errs > max_ecc_errs) + max_ecc_errs = ecc_errs; + } + + if (bounce) + nandi->cached_page = page_num; + +done: + buf += bytes; + len -= bytes; + + if (retlen) + *retlen += bytes; + + /* We are now page-aligned */ + page_offs += page_size; + page_num++; + col_offs = 0; + } + + /* Return '-EBADMSG' on uncorrectable errors */ + if (nandi->info.mtd.ecc_stats.failed - stats.failed) + return -EBADMSG; + + return max_ecc_errs; +} + +/* Helper function for mtd_write, to handle multi-page and non-aligned writes */ +static int bch_write(struct nandi_controller *nandi, + loff_t to, size_t len, + size_t *retlen, const uint8_t *buf) +{ + uint32_t page_size = nandi->info.mtd.writesize; + int page_num; + bool bounce = false; + const uint8_t *p = NULL; + uint8_t ret; + + dev_dbg(nandi->dev, "%s: %llu @ 0x%012llx\n", __func__, + (unsigned long long)len, to); + + BUG_ON(len & (page_size - 1)); + BUG_ON(to & (page_size - 1)); + + if (((unsigned long)buf & (NANDI_BCH_DMA_ALIGNMENT - 1)) || + !virt_addr_valid(buf)) { /* vmalloc'd buffer! */ + bounce = true; + } + + page_num = (int)(to >> nandi->page_shift); + + while (len > 0) { + if (bounce) { + memcpy(nandi->page_buf, buf, page_size); + p = nandi->page_buf; + nandi->cached_page = -1; + } else { + p = buf; + } + + if (nandi->cached_page == page_num) + nandi->cached_page = -1; + + ret = bch_write_page(nandi, to, p); + if (ret & NAND_STATUS_FAIL) + return -EIO; + + to += page_size; + page_num++; + buf += page_size; + len -= page_size; + + if (retlen) + *retlen += page_size; + } + + return 0; +} + /* * Hamming-FLEX operations */ -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
