From 8429bb3975ef81c114cde4da111e64d224d19f83 Mon Sep 17 00:00:00 2001 From: Brian Norris Date: Tue, 3 Dec 2013 15:51:09 -0800 Subject: mtd: nand: support Micron READ RETRY Micron provides READ RETRY support via the ONFI vendor-specific parameter block (to indicate how many read-retry modes are available) and the ONFI {GET,SET}_FEATURES commands with a vendor-specific feature address (to support reading/switching the current read-retry mode). The recommended sequence is as follows: 1. Perform PAGE_READ operation 2. If no ECC error, we are done 3. Run SET_FEATURES with feature address 89h, mode 1 4. Retry PAGE_READ operation 5. If ECC error and there are remaining supported modes, increment the mode and return to step 3. Otherwise, this is a true ECC error. 6. Run SET_FEATURES with feature address 89h, mode 0, to return to the default state. This patch implements the chip->setup_read_retry() callback for Micron and fills in the chip->read_retries. Tested on Micron MT29F32G08CBADA, which supports 8 read-retry modes. The Micron vendor-specific table was checked against the datasheets for the following Micron NAND: Needs retry Cell-type Part number Vendor revision Byte 180 ----------- --------- ---------------- --------------- ------------ No SLC MT29F16G08ABABA 1 Reserved (0) No MLC MT29F32G08CBABA 1 Reserved (0) No SLC MT29F1G08AACWP 1 0 Yes MLC MT29F32G08CBADA 1 08h Yes MLC MT29F64G08CBABA 2 08h Signed-off-by: Brian Norris Acked-by: Huang Shijie --- drivers/mtd/nand/nand_base.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'drivers/mtd') diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index 4c2f39f351da..b8c74cda7625 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -2979,6 +2979,30 @@ ext_out: return ret; } +static int nand_setup_read_retry_micron(struct mtd_info *mtd, int retry_mode) +{ + struct nand_chip *chip = mtd->priv; + uint8_t feature[ONFI_SUBFEATURE_PARAM_LEN] = {retry_mode}; + + return chip->onfi_set_features(mtd, chip, ONFI_FEATURE_ADDR_READ_RETRY, + feature); +} + +/* + * Configure chip properties from Micron vendor-specific ONFI table + */ +static void nand_onfi_detect_micron(struct nand_chip *chip, + struct nand_onfi_params *p) +{ + struct nand_onfi_vendor_micron *micron = (void *)p->vendor; + + if (le16_to_cpu(p->vendor_revision) < 1) + return; + + chip->read_retries = micron->read_retry_options; + chip->setup_read_retry = nand_setup_read_retry_micron; +} + /* * Check if the NAND chip is ONFI compliant, returns 1 if it is, 0 otherwise. */ @@ -3085,6 +3109,9 @@ static int nand_flash_detect_onfi(struct mtd_info *mtd, struct nand_chip *chip, pr_warn("Could not retrieve ONFI ECC requirements\n"); } + if (p->jedec_id == NAND_MFR_MICRON) + nand_onfi_detect_micron(chip, p); + return 1; } -- cgit v1.2.3