[PATCH] mtd: rawnand: qcom: Update code word value for raw read

Md Sadre Alam mdalam at codeaurora.org
Thu Aug 26 03:31:02 PDT 2021


>From QPIC V2 onwards there is a separate register to read
last code word "QPIC_NAND_READ_LOCATION_LAST_CW_n".

qcom_nandc_read_cw_raw() is used to read only one code word
at a time. If we will configure number of code words to 1 in
in QPIC_NAND_DEV0_CFG0 register then QPIC controller thinks
its reading the last code word, since from QPIC V2 onwards
we are having separate register to read the last code word,
we have to configure "QPIC_NAND_READ_LOCATION_LAST_CW_n"
register to fetch data from controller buffer to system
memory.

Signed-off-by: Md Sadre Alam <mdalam at codeaurora.org>
---
 drivers/mtd/nand/raw/qcom_nandc.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c
index ef0bade..04e6f7b 100644
--- a/drivers/mtd/nand/raw/qcom_nandc.c
+++ b/drivers/mtd/nand/raw/qcom_nandc.c
@@ -1676,13 +1676,17 @@ qcom_nandc_read_cw_raw(struct mtd_info *mtd, struct nand_chip *chip,
 	struct nand_ecc_ctrl *ecc = &chip->ecc;
 	int data_size1, data_size2, oob_size1, oob_size2;
 	int ret, reg_off = FLASH_BUF_ACC, read_loc = 0;
+	int raw_cw = cw;
 
 	nand_read_page_op(chip, page, 0, NULL, 0);
 	host->use_ecc = false;
 
+	if (nandc->props->qpic_v2)
+		raw_cw = ecc->steps - 1;
+
 	clear_bam_transaction(nandc);
 	set_address(host, host->cw_size * cw, page);
-	update_rw_regs(host, 1, true, cw);
+	update_rw_regs(host, 1, true, raw_cw);
 	config_nand_page_read(chip);
 
 	data_size1 = mtd->writesize - host->cw_size * (ecc->steps - 1);
@@ -1711,7 +1715,7 @@ qcom_nandc_read_cw_raw(struct mtd_info *mtd, struct nand_chip *chip,
 		nandc_set_read_loc(chip, cw, 3, read_loc, oob_size2, 1);
 	}
 
-	config_nand_cw_read(chip, false, cw);
+	config_nand_cw_read(chip, false, raw_cw);
 
 	read_data_dma(nandc, reg_off, data_buf, data_size1, 0);
 	reg_off += data_size1;
-- 
2.7.4




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