[PATCH] mmc: Fix potential timer value truncation

[Jaehoon Chung]

Hi,

> -----Original Message-----
> From: Ronald Wahl <rwahl at gmx.de>
> Sent: Thursday, December 12, 2024 5:52 AM
> From: Ronald Wahl <ronald.wahl at legrand.com>
>
> On 64bit systems the timer value might be truncated to a 32bit value
> causing malfunctions. For example on ARM the timer might start from 0
> again only after a cold reset. The 32bit overflow occurs after a bit
> more than 49 days (1000 Hz counter) so booting after that time may lead
> to a surprise because the board might become stuck requiring a cold
> reset.
>
> Signed-off-by: Ronald Wahl <ronald.wahl at legrand.com>
> Cc: Peng Fan <peng.fan at nxp.com>
> Cc: Jaehoon Chung <jh80.chung at samsung.com>

Reviewed-by: Jaehoon Chung <jh80.chung at samsung.com>

Best Regards,
Jaehoon Chung

> ---
>  drivers/mmc/mmc.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
> index efe98354a0..799586891a 100644
> --- a/drivers/mmc/mmc.c
> +++ b/drivers/mmc/mmc.c
> @@ -750,7 +750,7 @@ static int mmc_send_op_cond(struct mmc *mmc)
>  {
>  	int err, i;
>  	int timeout = 1000;
> -	uint start;
> +	ulong start;
>
>  	/* Some cards seem to need this */
>  	mmc_go_idle(mmc);
> @@ -844,7 +844,8 @@ int mmc_send_ext_csd(struct mmc *mmc, u8 *ext_csd)
>  static int __mmc_switch(struct mmc *mmc, u8 set, u8 index, u8 value,
>  			bool send_status)
>  {
> -	unsigned int status, start;
> +	ulong start;
> +	unsigned int status;
>  	struct mmc_cmd cmd;
>  	int timeout_ms = DEFAULT_CMD6_TIMEOUT_MS;
>  	bool is_part_switch = (set == EXT_CSD_CMD_SET_NORMAL) &&
> --
> 2.47.1