[Intel-gfx] [PATCH v3 1/1] drm/i915/pxp: Add missing tag for Wa_14019159160

[Matt Roper]

On Mon, Nov 27, 2023 at 12:11:50PM -0800, Alan Previn wrote:
> Add missing tag for "Wa_14019159160 - Case 2" (for existing
> PXP code that ensures run alone mode bit is set to allow
> PxP-decryption.
> 
>  v3: - Check targeted platforms using IP_VAL. (John Harrison)
>  v2: - Fix WA id number (John Harrison).
>      - Improve comments and code to be specific
>        for the targeted platforms (John Harrison)
> 
> Signed-off-by: Alan Previn <alan.previn.teres.alexis at intel.com>
> ---
>  drivers/gpu/drm/i915/gt/intel_lrc.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
> index 7c367ba8d9dc..1152cf25d578 100644
> --- a/drivers/gpu/drm/i915/gt/intel_lrc.c
> +++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
> @@ -863,10 +863,12 @@ static bool ctx_needs_runalone(const struct intel_context *ce)
>  	bool ctx_is_protected = false;
>  
>  	/*
> -	 * On MTL and newer platforms, protected contexts require setting
> -	 * the LRC run-alone bit or else the encryption will not happen.
> +	 * Wa_14019159160 - Case 2: mtl
> +	 * On some platforms, protected contexts require setting
> +	 * the LRC run-alone bit or else the encryption/decryption will not happen.
> +	 * NOTE: Case 2 only applies to PXP use-case of said workaround.
>  	 */
> -	if (GRAPHICS_VER_FULL(ce->engine->i915) >= IP_VER(12, 70) &&
> +	if (GRAPHICS_VER_FULL(ce->engine->i915) == IP_VER(12, 70) &&

The workaround database lists this as being needed on both 12.70 and
12.71.  Should this be a

        IS_GFX_GT_IP_RANGE(gt, IP_VER(12, 70), IP_VER(12, 71))

check instead?

The workaround is also listed in the database as applying to DG2; is
this "case 2" subset of the workaround not relevant to that platform?


Matt

>  	    (ce->engine->class == COMPUTE_CLASS || ce->engine->class == RENDER_CLASS)) {
>  		rcu_read_lock();
>  		gem_ctx = rcu_dereference(ce->gem_context);
> 
> base-commit: 5429d55de723544dfc0630cf39d96392052b27a1
> -- 
> 2.39.0
> 

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