[PATCH v4 01/20] mtd: nand: qcom: fix read failure without complete bootchain

Abhishek Sahu
2017-08-11T11:39:56Z

The NAND page read fails without complete boot chain since
NAND_DEV_CMD_VLD value is not proper. The default power on reset
value for this register is

0xe - ERASE_START_VALID | WRITE_START_VALID | READ_STOP_VALID

The READ_START_VALID should be enabled for sending PAGE_READ
command. READ_STOP_VALID should be cleared since normal NAND
page read does not require READ_STOP command.

Fixes: c76b78d8ec05a ("mtd: nand: Qualcomm NAND controller driver")
Cc: stable@vger.kernel.org
Reviewed-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
---
drivers/mtd/nand/qcom_nandc.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/mtd/nand/qcom_nandc.c b/drivers/mtd/nand/qcom_nandc.c
index 0e727d7..e5cb8f1 100644
--- a/drivers/mtd/nand/qcom_nandc.c
+++ b/drivers/mtd/nand/qcom_nandc.c
@@ -109,7 +109,11 @@
#define READ_ADDR 0

/* NAND_DEV_CMD_VLD bits */
-#define READ_START_VLD 0
+#define READ_START_VLD BIT(0)
+#define READ_STOP_VLD BIT(1)
+#define WRITE_START_VLD BIT(2)
+#define ERASE_START_VLD BIT(3)
+#define SEQ_READ_START_VLD BIT(4)

/* NAND_EBI2_ECC_BUF_CFG bits */
#define NUM_STEPS 0
@@ -148,6 +152,10 @@
#define FETCH_ID 0xb
#define RESET_DEVICE 0xd

+/* Default Value for NAND_DEV_CMD_VLD */
+#define NAND_DEV_CMD_VLD_VAL (READ_START_VLD | WRITE_START_VLD | \
+ ERASE_START_VLD | SEQ_READ_START_VLD)
+
/*
* the NAND controller performs reads/writes with ECC in 516 byte chunks.
* the driver calls the chunks 'step' or 'codeword' interchangeably
@@ -695,8 +703,7 @@ static int nandc_param(struct qcom_nand_host *host)

/* configure CMD1 and VLD for ONFI param probing */
nandc_set_reg(nandc, NAND_DEV_CMD_VLD,
- (nandc->vld & ~(1 << READ_START_VLD))
- | 0 << READ_START_VLD);
+ (nandc->vld & ~READ_START_VLD));
nandc_set_reg(nandc, NAND_DEV_CMD1,
(nandc->cmd1 & ~(0xFF << READ_ADDR))
| NAND_CMD_PARAM << READ_ADDR);
@@ -1995,13 +2002,14 @@ static int qcom_nandc_setup(struct qcom_nand_controller *nandc)
{
/* kill onenand */
nandc_write(nandc, SFLASHC_BURST_CFG, 0);
+ nandc_write(nandc, NAND_DEV_CMD_VLD, NAND_DEV_CMD_VLD_VAL);

/* enable ADM DMA */
nandc_write(nandc, NAND_FLASH_CHIP_SELECT, DM_EN);

/* save the original values of these registers */
nandc->cmd1 = nandc_read(nandc, NAND_DEV_CMD1);
- nandc->vld = nandc_read(nandc, NAND_DEV_CMD_VLD);
+ nandc->vld = NAND_DEV_CMD_VLD_VAL;

return 0;
}