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@vger.kernel.org
Fixes: 89550beb098e ("mtd: rawnand: qcom: Implement exec_op()")
Signed-off-by: Md Sadre Alam <quic_mdalam@quicinc.com>
---
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