Re: [PATCH v5 1/1] drm/i915/pxp: Add missing tag for Wa_14019159160

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

On Tue, Oct 15, 2024 at 05:16:58PM -0700, 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.
> 
>  v5: - remove the max IP_VER check since new platforms that
>        i915 supports needs this fix and tag the caller too
>        (John Harrison).
>  v4: - Include IP_VER 12.71. (Matt Roper)
>  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@intel.com>
> ---
>  drivers/gpu/drm/i915/gt/intel_lrc.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/gt/intel_lrc.c b/drivers/gpu/drm/i915/gt/intel_lrc.c
> index 7bd5d2c29056..51847a846002 100644
> --- a/drivers/gpu/drm/i915/gt/intel_lrc.c
> +++ b/drivers/gpu/drm/i915/gt/intel_lrc.c
> @@ -820,8 +820,10 @@ 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.
> +	 * 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) &&
>  	    (ce->engine->class == COMPUTE_CLASS || ce->engine->class == RENDER_CLASS)) {
> @@ -850,6 +852,7 @@ static void init_common_regs(u32 * const regs,
>  	if (GRAPHICS_VER(engine->i915) < 11)
>  		ctl |= _MASKED_BIT_DISABLE(CTX_CTRL_ENGINE_CTX_SAVE_INHIBIT |
>  					   CTX_CTRL_RS_CTX_ENABLE);
> +	/* Wa_14019159160 - Case 2.*/

I don't believe this needs to be repeated, but it doesn't hurt

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

>  	if (ctx_needs_runalone(ce))
>  		ctl |= _MASKED_BIT_ENABLE(GEN12_CTX_CTRL_RUNALONE_MODE);
>  	regs[CTX_CONTEXT_CONTROL] = ctl;
> 
> base-commit: 01c7b2c084e5c84313f382734c10945b9aa49823
> -- 
> 2.34.1
>