Re: [PATCH] i2c: designware: Modify timing parameters for amdpsp mailbox

Jarkko Nikula
2022-04-28T13:08:00Z

On 4/28/22 15:26, Jan Dabros wrote:
> Adjust retry period and timeout values for x86-PSP mailbox based on the
> typical I2C traffic generated by PSP. In order to limit the possibility
> of timeouts, x86 should reduce the interval between retries as well as
> increase overall time after which it gives up.
>
> Signed-off-by: Jan Dabros <jsd@semihalf.com>
> ---
> drivers/i2c/busses/i2c-designware-amdpsp.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-designware-amdpsp.c b/drivers/i2c/busses/i2c-designware-amdpsp.c
> index 9b37f2b95abc..b624356c945f 100644
> --- a/drivers/i2c/busses/i2c-designware-amdpsp.c
> +++ b/drivers/i2c/busses/i2c-designware-amdpsp.c
> @@ -16,8 +16,8 @@
> #define PSP_CMD_TIMEOUT_US (500 * USEC_PER_MSEC)
>
> #define PSP_I2C_REQ_BUS_CMD 0x64
> -#define PSP_I2C_REQ_RETRY_CNT 10
> -#define PSP_I2C_REQ_RETRY_DELAY_US (50 * USEC_PER_MSEC)
> +#define PSP_I2C_REQ_RETRY_CNT 400
> +#define PSP_I2C_REQ_RETRY_DELAY_US (25 * USEC_PER_MSEC)
> #define PSP_I2C_REQ_STS_OK 0x0
> #define PSP_I2C_REQ_STS_BUS_BUSY 0x1
> #define PSP_I2C_REQ_STS_INV_PARAM 0x3

Out of curiosity, can it be up to 400 * 25 ms = 10 s?

Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>