[PATCH 1/2] drm/xe/guc: Update VF configuration KLVs definitions

[Piotr Piórkowski]

Michal Wajdeczko <michal.wajdeczko at intel.com> wrote on pią [2024-kwi-19 14:35:42 +0200]:
> GuC firmware specification says that maximum value for the execution
> quantum KLV is 100s and anything exceeding that will be clamped.
> The same limitation applies to the preemption timeout KLV.
> 
> Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
> ---
>  drivers/gpu/drm/xe/abi/guc_klvs_abi.h | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/abi/guc_klvs_abi.h b/drivers/gpu/drm/xe/abi/guc_klvs_abi.h
> index 511cf974d585..e53ffaee2fcd 100644
> --- a/drivers/gpu/drm/xe/abi/guc_klvs_abi.h
> +++ b/drivers/gpu/drm/xe/abi/guc_klvs_abi.h
> @@ -201,7 +201,11 @@ enum  {
>   *      it to take effect. Such cases might typically happen on a 1PF+1VF
>   *      Virtualization config enabled for heavier workloads like AI/ML.
>   *
> + *      The max value for this KLV is 100 seconds, anything exceeding that
> + *      will be clamped to the max.
> + *
>   *      :0: infinite exec quantum (default)
> + *      :100000: maximum exec quantum (100000ms == 100s)
>   *
>   * _`GUC_KLV_VF_CFG_PREEMPT_TIMEOUT` : 0x8A02
>   *      This config sets the VF-preemption-timeout in microseconds.
> @@ -219,7 +223,11 @@ enum  {
>   *      on a 1PF+1VF Virtualization config enabled for heavier workloads like
>   *      AI/ML.
>   *
> + *      The max value for this KLV is 100 seconds, anything exceeding that
> + *      will be clamped to the max.
> + *
>   *      :0: no preemption timeout (default)
> + *      :100000000: maximum preemption timeout (100000000us == 100s)
>   *
>   * _`GUC_KLV_VF_CFG_THRESHOLD_CAT_ERR` : 0x8A03
>   *      This config sets threshold for CAT errors caused by the VF.
> @@ -291,9 +299,11 @@ enum  {
>  
>  #define GUC_KLV_VF_CFG_EXEC_QUANTUM_KEY		0x8a01
>  #define GUC_KLV_VF_CFG_EXEC_QUANTUM_LEN		1u
> +#define GUC_KLV_VF_CFG_EXEC_QUANTUM_MAX_VALUE	100000u
>  
> -#define GUC_KLV_VF_CFG_PREEMPT_TIMEOUT_KEY	0x8a02
> -#define GUC_KLV_VF_CFG_PREEMPT_TIMEOUT_LEN	1u
> +#define GUC_KLV_VF_CFG_PREEMPT_TIMEOUT_KEY		0x8a02
> +#define GUC_KLV_VF_CFG_PREEMPT_TIMEOUT_LEN		1u
> +#define GUC_KLV_VF_CFG_PREEMPT_TIMEOUT_MAX_VALUE	100000000u
>  
>  #define GUC_KLV_VF_CFG_THRESHOLD_CAT_ERR_KEY		0x8a03
>  #define GUC_KLV_VF_CFG_THRESHOLD_CAT_ERR_LEN		1u


Your code is ok:
Reviewed-by: Piotr Piórkowski <piotr.piorkowski at intel.com>

But since you are already updating the doc for these values, wouldn't you like to maybe correct
a typo in the doc ? If you don't correct it, it will probably stay there forever.... :

(...)
 * _`GUC_KLV_VF_CFG_EXEC_QUANTUM` : 0x8A01
(...)
 *      That said, when the PF is changing this value from 0xFFFFFFFF to
 *      something else, it might never take effect if the VF is running an
 *      inifinitely long compute or shader kernel. In such a scenario, the
 *      PF would need to trigger a VM PAUSE and then change the KLV to force
 *      it to take effect. Such cases might typically happen on a 1PF+1VF
 *      Virtualization config enabled for heavier workloads like AI/ML.

 Typo: inifinitely, should be infinitely

Tha same for GUC_KLV_VF_CFG_PREEMPT_TIMEOUT

Thanks,
Piotr
> -- 
> 2.43.0
> 

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