[PATCH] drm/i915: Do not attempt to load the GSC multiple times

[Cavitt, Jonathan]

-----Original Message-----
From: Intel-gfx <intel-gfx-bounces at lists.freedesktop.org> On Behalf Of Daniele Ceraolo Spurio
Sent: Tuesday, August 20, 2024 3:00 PM
To: intel-gfx at lists.freedesktop.org
Cc: Ceraolo Spurio, Daniele <daniele.ceraolospurio at intel.com>; Teres Alexis, Alan Previn <alan.previn.teres.alexis at intel.com>; Harrison, John C <john.c.harrison at intel.com>; Vivi, Rodrigo <rodrigo.vivi at intel.com>
Subject: [PATCH] drm/i915: Do not attempt to load the GSC multiple times
> 
> If the GSC FW fails to load the GSC HW hangs permanently; the only ways
> to recover it are FLR or D3cold entry, with the former only being
> supported on driver unload and the latter only on DGFX, for which we
> don't need to load the GSC. Therefore, if GSC fails to load there is no
> need to try again because the HW is stuck in the error state and the
> submission to load the FW would just hang the GSCCS.
> 
> Note that, due to wa_14015076503, on MTL the GuC escalates all GSCCS
> hangs to full GT resets, which would trigger a new attempt to load the
> GSC FW in the post-reset HW re-init; this issue is also fixed by not
> attempting to load the GSC FW after an error.
> 
> Fixes: 15bd4a67e914 ("drm/i915/gsc: GSC firmware loading")
> Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
> Cc: Alan Previn <alan.previn.teres.alexis at intel.com>
> Cc: John Harrison <John.C.Harrison at Intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>

LGTM.
Reviewed-by: Jonathan Cavitt <jonathan.cavitt at intel.com>
-Jonathan Cavitt

> ---
>  drivers/gpu/drm/i915/gt/uc/intel_gsc_uc.c | 2 +-
>  drivers/gpu/drm/i915/gt/uc/intel_uc_fw.h  | 5 +++++
>  2 files changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_gsc_uc.c b/drivers/gpu/drm/i915/gt/uc/intel_gsc_uc.c
> index 453d855dd1de..3d3191deb0ab 100644
> --- a/drivers/gpu/drm/i915/gt/uc/intel_gsc_uc.c
> +++ b/drivers/gpu/drm/i915/gt/uc/intel_gsc_uc.c
> @@ -302,7 +302,7 @@ void intel_gsc_uc_load_start(struct intel_gsc_uc *gsc)
>  {
>  	struct intel_gt *gt = gsc_uc_to_gt(gsc);
>  
> -	if (!intel_uc_fw_is_loadable(&gsc->fw))
> +	if (!intel_uc_fw_is_loadable(&gsc->fw) || intel_uc_fw_is_in_error(&gsc->fw))
>  		return;
>  
>  	if (intel_gsc_uc_fw_init_done(gsc))
> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.h b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.h
> index 9a431726c8d5..ac7b3aad2222 100644
> --- a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.h
> +++ b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.h
> @@ -258,6 +258,11 @@ static inline bool intel_uc_fw_is_running(struct intel_uc_fw *uc_fw)
>  	return __intel_uc_fw_status(uc_fw) == INTEL_UC_FIRMWARE_RUNNING;
>  }
>  
> +static inline bool intel_uc_fw_is_in_error(struct intel_uc_fw *uc_fw)
> +{
> +	return intel_uc_fw_status_to_error(__intel_uc_fw_status(uc_fw)) != 0;
> +}
> +
>  static inline bool intel_uc_fw_is_overridden(const struct intel_uc_fw *uc_fw)
>  {
>  	return uc_fw->user_overridden;
> -- 
> 2.43.0
> 
>