For QPIC V2 onwards there is a separate register to read last code word "QPIC_NAND_READ_LOCATION_LAST_CW_n". qcom_param_page_type_exec() is used to read only one code word If it will get configure number of code words to 1 in QPIC_NAND_DEV0_CFG0 register then QPIC controller thinks its reading the last code word, since 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 QPIC buffer to system memory. Without this change page read was failing with timeout error / # hexdump -C /dev/mtd1 [ 129.206113] qcom-nandc 1cc8000.nand-controller: failure to read page/oob hexdump: /dev/mtd1: Connection timed out This issue only seen on SDX targets since SDX target used QPICv2. But same working on IPQ targets since IPQ used QPICv1. Cc: stable@xxxxxxxxxxxxxxx Fixes: 89550beb098e ("mtd: rawnand: qcom: Implement exec_op()") Signed-off-by: Md Sadre Alam <quic_mdalam@xxxxxxxxxxx> --- Change in [v2] * Updated commit message * Added stable kernel tag * Replaced the buf_count value of 512 with the len in bytes. Change in [v1] * Resolved the issue with reading a single code word in the parameter page read drivers/mtd/nand/raw/qcom_nandc.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c index cc59461df72e..31ec3db1246d 100644 --- a/drivers/mtd/nand/raw/qcom_nandc.c +++ b/drivers/mtd/nand/raw/qcom_nandc.c @@ -2859,7 +2859,12 @@ static int qcom_param_page_type_exec(struct nand_chip *chip, const struct nand_ const struct nand_op_instr *instr = NULL; unsigned int op_id = 0; unsigned int len = 0; - int ret; + int ret, reg_base; + + reg_base = NAND_READ_LOCATION_0; + + if (nandc->props->qpic_v2) + reg_base = NAND_READ_LOCATION_LAST_CW_0; ret = qcom_parse_instructions(chip, subop, &q_op); if (ret) @@ -2911,7 +2916,10 @@ static int qcom_param_page_type_exec(struct nand_chip *chip, const struct nand_ op_id = q_op.data_instr_idx; len = nand_subop_get_data_len(subop, op_id); - nandc_set_read_loc(chip, 0, 0, 0, len, 1); + if (nandc->props->qpic_v2) + nandc_set_read_loc_last(chip, reg_base, 0, len, 1); + else + nandc_set_read_loc_first(chip, reg_base, 0, len, 1); if (!nandc->props->qpic_v2) { write_reg_dma(nandc, NAND_DEV_CMD_VLD, 1, 0); -- 2.34.1