[PATCH] mtd: rawnand: davinci: Reduce polling interval in NAND_OP_WAITRDY_INSTR

[PATCH] mtd: rawnand: davinci: Reduce polling interval in NAND_OP_WAITRDY_INSTR

[Bastien Curutchet]

For each NAND_OP_WAITRDY_INSTR operation, the NANDFSR register is
polled only once every 100 us to check for the EMA_WAIT pin. This
isn't frequent enough and causes delays in NAND accesses.

Set the polling interval to 0s. It increases the page read speed
reported by flash_speed by ~40% (~30% on page writes).

---
Signed-off-by: Bastien Curutchet <bastien.curutchet@bootlin.com>
---
 drivers/mtd/nand/raw/davinci_nand.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/raw/davinci_nand.c b/drivers/mtd/nand/raw/davinci_nand.c
index 1f8354acfb50b2f4d155cdfc03afcf2863539f66..b3fe6f62bb3bd6a51da891c604d38142055ab1d3 100644
--- a/drivers/mtd/nand/raw/davinci_nand.c
+++ b/drivers/mtd/nand/raw/davinci_nand.c
@@ -724,7 +724,7 @@ static int davinci_nand_exec_instr(struct davinci_nand_info *info,
 	case NAND_OP_WAITRDY_INSTR:
 		timeout_us = instr->ctx.waitrdy.timeout_ms * 1000;
 		ret = readl_relaxed_poll_timeout(info->base + NANDFSR_OFFSET,
-						 status, status & BIT(0), 100,
+						 status, status & BIT(0), 0,
 						 timeout_us);
 		if (ret)
 			return ret;

---
base-commit: 40384c840ea1944d7c5a392e8975ed088ecf0b37
change-id: 20241219-patch-nand-poll-b215766ea0a2

Best regards,
-- 
Bastien Curutchet <bastien.curutchet@bootlin.com>

Re: [PATCH] mtd: rawnand: davinci: Reduce polling interval in NAND_OP_WAITRDY_INSTR

[Bastien Curutchet]

Hi all,

On 12/19/24 3:25 PM, Bastien Curutchet wrote:
> For each NAND_OP_WAITRDY_INSTR operation, the NANDFSR register is
> polled only once every 100 us to check for the EMA_WAIT pin. This
> isn't frequent enough and causes delays in NAND accesses.
> 
> Set the polling interval to 0s. It increases the page read speed
> reported by flash_speed by ~40% (~30% on page writes).
> 
> ---
> Signed-off-by: Bastien Curutchet <bastien.curutchet@bootlin.com>

I just realized that this SOB should be above the '---'. Sorry about 
that, I'll send a V2 right away.

Best regards,
Bastien