Re: [PATCH] drm/xe: Enable SR-IOV for PTL

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Thu, Feb 06, 2025 at 10:45:45PM +0100, Michal Wajdeczko wrote:
> We should now have sufficient changes in the driver to run it on
> PTL platforms in the SR-IOV Physical Function (PF) mode, that would
> allow us to enable SR-IOV Virtual Functions (VFs), and successfully
> probe our driver in the VF mode on enabled VF devices.
> 
> To unblock SR-IOV PF mode you need to load xe with modparam:
> 
>  xe.max_vfs=7
> 
> Then to enable VFs it is sufficient to use:
> 
>  $ echo 7 > /sys/bus/pci/devices/0000:00:02.0/sriov_numvfs
> 
> Note that in default auto-provisioning all VFs are allocated with
> some amount of shared resources (like unlimited GPU execution and
> preemption times, fair GGTT space, fair GuC context IDs range, ...)
> 
> However with CONFIG_DEBUG_FS enabled it is possible to tweak most
> of the SR-IOV configuration parameters using attributes like:
> 
>  /sys/kernel/debug/dri/0000:00:02.0/gt0/
>  ├── pf
>  │   ├── contexts_spare
>  │   ├── doorbells_spare
>  │   ├── exec_quantum_ms
>  │   ├── ggtt_spare
>  │   ├── preempt_timeout_us
>  │   ├── sched_priority
>  │   └── ...
>  ├── vf1
>  │   ├── contexts_quota
>  │   ├── doorbells_quota
>  │   ├── exec_quantum_ms
>  │   ├── ggtt_quota
>  │   ├── preempt_timeout_us
>  │   ├── sched_priority
>  │   └── ...
>  ├── vf2
>  │   └── ...
>  :
> 
> Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Cc: Lucas De Marchi <lucas.demarchi@intel.com>
> Cc: Thomas Hellstrom <thomas.hellstrom@linux.intel.com>
> ---
> Cc: Piotr Piórkowski <piotr.piorkowski@intel.com>
> Cc: Jakub Kolakowski <jakub1.kolakowski@intel.com>
> Cc: Marcin Bernatowicz <marcin.bernatowicz@linux.intel.com>
> ---
>  drivers/gpu/drm/xe/xe_pci.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/xe/xe_pci.c b/drivers/gpu/drm/xe/xe_pci.c
> index e8ef7d6b4db8..6a8e82aff385 100644
> --- a/drivers/gpu/drm/xe/xe_pci.c
> +++ b/drivers/gpu/drm/xe/xe_pci.c
> @@ -367,6 +367,7 @@ static const struct xe_device_desc ptl_desc = {
>  	PLATFORM(PANTHERLAKE),
>  	.dma_mask_size = 46,
>  	.has_display = true,
> +	.has_sriov = true,

Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

>  	.require_force_probe = true,
>  };
>  
> -- 
> 2.47.1
>