[RFC 40/47] mtd: nand: stm_nand_bch: MTD erase (BCH)

Lee Jones
2014-03-25T08:22:03Z

Carry out the normal checks, then attempt to erase a given block.

Signed-off-by: Lee Jones <lee.jones@linaro.org>
---
drivers/mtd/nand/stm_nand_bch.c | 85 +++++++++++++++++++++++++++++++++++++++++
1 file changed, 85 insertions(+)

diff --git a/drivers/mtd/nand/stm_nand_bch.c b/drivers/mtd/nand/stm_nand_bch.c
index 75c5c9b..55f4a4c 100644
--- a/drivers/mtd/nand/stm_nand_bch.c
+++ b/drivers/mtd/nand/stm_nand_bch.c
@@ -1218,6 +1218,89 @@ static int flex_do_write_ops(struct nandi_controller *nandi,
return 0;
}

+static int bch_mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
+{
+ struct nand_chip *chip = mtd->priv;
+ struct nandi_controller *nandi = chip->priv;
+ uint64_t block_mask = mtd->erasesize - 1;
+ uint64_t offs_cached;
+ loff_t offs = instr->addr;
+ size_t len = instr->len;
+ uint8_t status;
+ int ret;
+
+ dev_dbg(nandi->dev, "%s: 0x%012llx @ 0x%012llx\n", __func__,
+ (unsigned long long)len, offs);
+
+ if (offs & block_mask) {
+ dev_err(nandi->dev,
+ "attempt to erase from non-block-aligned offset\n");
+ return -EINVAL;
+ }
+
+ if (len & block_mask) {
+ dev_err(nandi->dev,
+ "attempt to erase non-block-aligned length\n");
+ return -EINVAL;
+ }
+
+ if ((offs + len) > mtd->size) {
+ dev_err(nandi->dev, "attempt to erase past end of device\n");
+ return -EINVAL;
+ }
+
+ nand_get_device(mtd, FL_ERASING);
+ instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
+
+ if (flex_check_wp(nandi)) {
+ dev_dbg(nandi->dev, "device is write-protected\n");
+ instr->state = MTD_ERASE_FAILED;
+ goto erase_exit;
+ }
+
+ /* Offset of block containing cached page */
+ offs_cached = ((uint64_t)nandi->cached_page << nandi->page_shift) &
+ ~block_mask;
+
+ instr->state = MTD_ERASING;
+ while (len) {
+ if (mtd_block_isbad(mtd, offs)) {
+ dev_err(nandi->dev,
+ "attempt to erase a bad block at 0x%012llx\n",
+ offs);
+ instr->state = MTD_ERASE_FAILED;
+ instr->fail_addr = offs;
+ goto erase_exit;
+ }
+
+ if (offs == offs_cached)
+ nandi->cached_page = -1;
+
+ status = bch_erase_block(nandi, offs);
+
+ if (status & NAND_STATUS_FAIL) {
+ dev_err(nandi->dev,
+ "failed to erase block at 0x%012llx\n", offs);
+ instr->state = MTD_ERASE_FAILED;
+ instr->fail_addr = offs;
+ goto erase_exit;
+ }
+
+ len -= mtd->erasesize;
+ offs += mtd->erasesize;
+ }
+ instr->state = MTD_ERASE_DONE;
+
+ erase_exit:
+ nand_release_device(mtd);
+
+ ret = instr->state == MTD_ERASE_DONE ? 0 : -EIO;
+ if (ret == 0)
+ mtd_erase_callback(instr);
+
+ return ret;
+}
+
static void nandi_dump_bad_blocks(struct nandi_controller *nandi)
{
int bad_count = 0;
@@ -1321,6 +1404,8 @@ static void nandi_set_mtd_defaults(struct nandi_controller *nandi,
mtd->oobavail = 0;
mtd->subpage_sft = 0;

+ mtd->_erase = bch_mtd_erase;
+
mtd->_point = NULL;
mtd->_unpoint = NULL;
mtd->_lock = NULL;
--
1.8.3.2