[PATCH 1/8] drm/xe/vf: Assume fixed GSM size if VF

[Matt Roper]

On Fri, Jan 12, 2024 at 04:26:42PM +0100, Michal Wajdeczko wrote:
> VFs can't use size mirrored from PCI config, but it should be
> safe to assume it covers full 4GiB GGTT.
> 
> Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
> Cc: Matt Roper <matthew.d.roper at intel.com>

Matches bspec 70494 & 50588.

Reviewed-by: Matt Roper <matthew.d.roper at intel.com>

> ---
>  drivers/gpu/drm/xe/xe_ggtt.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_ggtt.c b/drivers/gpu/drm/xe/xe_ggtt.c
> index 6fdf830678b3..ab96edb058d6 100644
> --- a/drivers/gpu/drm/xe/xe_ggtt.c
> +++ b/drivers/gpu/drm/xe/xe_ggtt.c
> @@ -20,6 +20,7 @@
>  #include "xe_gt_tlb_invalidation.h"
>  #include "xe_map.h"
>  #include "xe_mmio.h"
> +#include "xe_sriov.h"
>  #include "xe_wopcm.h"
>  
>  #define XELPG_GGTT_PTE_PAT0	BIT_ULL(52)
> @@ -144,7 +145,11 @@ int xe_ggtt_init_early(struct xe_ggtt *ggtt)
>  	struct pci_dev *pdev = to_pci_dev(xe->drm.dev);
>  	unsigned int gsm_size;
>  
> -	gsm_size = probe_gsm_size(pdev);
> +	if (IS_SRIOV_VF(xe))
> +		gsm_size = SZ_8M; /* GGTT is expected to be 4GiB */
> +	else
> +		gsm_size = probe_gsm_size(pdev);
> +
>  	if (gsm_size == 0) {
>  		drm_err(&xe->drm, "Hardware reported no preallocated GSM\n");
>  		return -ENOMEM;
> -- 
> 2.25.1
> 

-- 
Matt Roper
Graphics Software Engineer
Linux GPU Platform Enablement
Intel Corporation