diff mbox series

[v3,2/5] mtd: rawnand: brcmnand: Fix potential false time out warning

Message ID 20230627193738.19596-3-william.zhang@broadcom.com
State New
Headers
Series mtd: rawnand: brcmnand: driver and doc updates |

Commit Message

William Zhang June 27, 2023, 7:37 p.m. UTC 
  If system is busy during the command status polling function, the driver
may not get the chance to poll the status register till the end of time
out and return the premature status.  Do a final check after time out
happens to ensure reading the correct status.

Fixes: 9d2ee0a60b8b ("mtd: nand: brcmnand: Check flash #WP pin status before nand erase/program")
Signed-off-by: William Zhang <william.zhang@broadcom.com>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
---

Changes in v3: None
Changes in v2: None

 drivers/mtd/nand/raw/brcmnand/brcmnand.c | 8 ++++++++
 1 file changed, 8 insertions(+)

Comments

Miquel Raynal July 4, 2023, 3:21 p.m. UTC | #1 
Hi William,

william.zhang@broadcom.com wrote on Tue, 27 Jun 2023 12:37:35 -0700:

> If system is busy during the command status polling function, the driver
> may not get the chance to poll the status register till the end of time
> out and return the premature status.  Do a final check after time out
> happens to ensure reading the correct status.
> 
> Fixes: 9d2ee0a60b8b ("mtd: nand: brcmnand: Check flash #WP pin status before nand erase/program")
> Signed-off-by: William Zhang <william.zhang@broadcom.com>
> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>

Cc: stable here and in patch 1 as well.

> ---
> 
> Changes in v3: None
> Changes in v2: None
> 
>  drivers/mtd/nand/raw/brcmnand/brcmnand.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> index 69709419516a..37c2c7cfa00e 100644
> --- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> +++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> @@ -1080,6 +1080,14 @@ static int bcmnand_ctrl_poll_status(struct brcmnand_controller *ctrl,
>  		cpu_relax();
>  	} while (time_after(limit, jiffies));
>  
> +	/*
> +	 * do a final check after time out in case CPU is busy and driver does
> +	 * not get the enough time to poll to avoid false alarm

Do a final... ...the CPU was busy and the driver did not get enough
time to perform the polling to avoid false alarms.

> +	 */
> +	val = brcmnand_read_reg(ctrl, BRCMNAND_INTFC_STATUS);
> +	if ((val & mask) == expected_val)
> +		return 0;
> +
>  	dev_warn(ctrl->dev, "timeout on status poll (expected %x got %x)\n",
>  		 expected_val, val & mask);
>  

Otherwise looks good.

Thanks,
Miquèl
diff mbox series

Patch

diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
index 69709419516a..37c2c7cfa00e 100644
--- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
+++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
@@ -1080,6 +1080,14 @@  static int bcmnand_ctrl_poll_status(struct brcmnand_controller *ctrl,
 		cpu_relax();
 	} while (time_after(limit, jiffies));
 
+	/*
+	 * do a final check after time out in case CPU is busy and driver does
+	 * not get the enough time to poll to avoid false alarm
+	 */
+	val = brcmnand_read_reg(ctrl, BRCMNAND_INTFC_STATUS);
+	if ((val & mask) == expected_val)
+		return 0;
+
 	dev_warn(ctrl->dev, "timeout on status poll (expected %x got %x)\n",
 		 expected_val, val & mask);