Re: [Intel-gfx] [PATCH v2 3/9] drm/i915/xelpg: Call Xe_LPG workaround functions based on IP version

[Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>]

On 25/07/2023 01:13, Matt Roper wrote:
> Although some of our Xe_LPG workarounds were already being applied based
> on IP version correctly, others were matching on MTL as a base platform,
> which is incorrect.  Although MTL is the only platform right now that
> uses Xe_LPG IP, this may not always be the case.  If a future platform
> re-uses this graphics IP, the same workarounds should be applied, even
> if it isn't a "MTL" platform.
> 
> We were also incorrectly applying Xe_LPG workarounds/tuning to the
> Xe_LPM+ media IP in one or two places; we should make sure that we don't
> try to apply graphics workarounds to the media GT and vice versa where
> they don't belong.  A new helper macro IS_GT_IP_RANGE() is added to help
> ensure this is handled properly -- it checks that the GT matches the IP
> type being tested as well as the IP version falling in the proper range.
> 
> Note that many of the stepping-based workarounds are still incorrectly
> checking for a MTL base platform; that will be remedied in a later
> patch.
> 
> v2:
>   - Rework macro into a slightly more generic IS_GT_IP_RANGE() that can
>     be used for either GFX or MEDIA checks.
> 
> Cc: Gustavo Sousa <gustavo.sousa@intel.com>
> Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
> Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
> ---
>   drivers/gpu/drm/i915/gt/intel_workarounds.c | 38 +++++++++++----------
>   drivers/gpu/drm/i915/i915_drv.h             | 23 +++++++++++++
>   2 files changed, 43 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c
> index d8a1eaa44e69..c4663541c5dd 100644
> --- a/drivers/gpu/drm/i915/gt/intel_workarounds.c
> +++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c
> @@ -805,8 +805,8 @@ static void dg2_ctx_workarounds_init(struct intel_engine_cs *engine,
>   	wa_masked_en(wal, CACHE_MODE_1, MSAA_OPTIMIZATION_REDUC_DISABLE);
>   }
>   
> -static void mtl_ctx_gt_tuning_init(struct intel_engine_cs *engine,
> -				   struct i915_wa_list *wal)
> +static void xelpg_ctx_gt_tuning_init(struct intel_engine_cs *engine,
> +				     struct i915_wa_list *wal)
>   {
>   	struct drm_i915_private *i915 = engine->i915;
>   
> @@ -817,12 +817,12 @@ static void mtl_ctx_gt_tuning_init(struct intel_engine_cs *engine,
>   		wa_add(wal, DRAW_WATERMARK, VERT_WM_VAL, 0x3FF, 0, false);
>   }
>   
> -static void mtl_ctx_workarounds_init(struct intel_engine_cs *engine,
> -				     struct i915_wa_list *wal)
> +static void xelpg_ctx_workarounds_init(struct intel_engine_cs *engine,
> +				       struct i915_wa_list *wal)
>   {
>   	struct drm_i915_private *i915 = engine->i915;
>   
> -	mtl_ctx_gt_tuning_init(engine, wal);
> +	xelpg_ctx_gt_tuning_init(engine, wal);
>   
>   	if (IS_MTL_GRAPHICS_STEP(i915, M, STEP_A0, STEP_B0) ||
>   	    IS_MTL_GRAPHICS_STEP(i915, P, STEP_A0, STEP_B0)) {
> @@ -931,8 +931,8 @@ __intel_engine_init_ctx_wa(struct intel_engine_cs *engine,
>   	if (engine->class != RENDER_CLASS)
>   		goto done;
>   
> -	if (IS_METEORLAKE(i915))
> -		mtl_ctx_workarounds_init(engine, wal);
> +	if (IS_GT_IP_RANGE(GFX, engine->gt, IP_VER(12, 70), IP_VER(12, 71)))
> +		xelpg_ctx_workarounds_init(engine, wal);
>   	else if (IS_PONTEVECCHIO(i915))
>   		; /* noop; none at this time */
>   	else if (IS_DG2(i915))
> @@ -1790,10 +1790,8 @@ xelpmp_gt_workarounds_init(struct intel_gt *gt, struct i915_wa_list *wal)
>    */
>   static void gt_tuning_settings(struct intel_gt *gt, struct i915_wa_list *wal)
>   {
> -	if (IS_METEORLAKE(gt->i915)) {
> -		if (gt->type != GT_MEDIA)
> -			wa_mcr_write_or(wal, XEHP_L3SCQREG7, BLEND_FILL_CACHING_OPT_DIS);
> -
> +	if (IS_GT_IP_RANGE(GFX, gt, IP_VER(12, 70), IP_VER(12, 71))) {
> +		wa_mcr_write_or(wal, XEHP_L3SCQREG7, BLEND_FILL_CACHING_OPT_DIS);
>   		wa_mcr_write_or(wal, XEHP_SQCM, EN_32B_ACCESS);
>   	}
>   
> @@ -1825,7 +1823,7 @@ gt_init_workarounds(struct intel_gt *gt, struct i915_wa_list *wal)
>   		return;
>   	}
>   
> -	if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 70))
> +	if (IS_GT_IP_RANGE(GFX, gt, IP_VER(12, 70), IP_VER(12, 71)))
>   		xelpg_gt_workarounds_init(gt, wal);
>   	else if (IS_PONTEVECCHIO(i915))
>   		pvc_gt_workarounds_init(gt, wal);
> @@ -2293,7 +2291,7 @@ static void pvc_whitelist_build(struct intel_engine_cs *engine)
>   	blacklist_trtt(engine);
>   }
>   
> -static void mtl_whitelist_build(struct intel_engine_cs *engine)
> +static void xelpg_whitelist_build(struct intel_engine_cs *engine)
>   {
>   	struct i915_wa_list *w = &engine->whitelist;
>   
> @@ -2315,8 +2313,10 @@ void intel_engine_init_whitelist(struct intel_engine_cs *engine)
>   
>   	wa_init_start(w, engine->gt, "whitelist", engine->name);
>   
> -	if (IS_METEORLAKE(i915))
> -		mtl_whitelist_build(engine);
> +	if (engine->gt->type == GT_MEDIA)
> +		; /* none yet */
> +	else if (IS_GT_IP_RANGE(GFX, engine->gt, IP_VER(12, 70), IP_VER(12, 71)))
> +		xelpg_whitelist_build(engine);
>   	else if (IS_PONTEVECCHIO(i915))
>   		pvc_whitelist_build(engine);
>   	else if (IS_DG2(i915))
> @@ -2974,10 +2974,12 @@ ccs_engine_wa_init(struct intel_engine_cs *engine, struct i915_wa_list *wal)
>    * function invoked by __intel_engine_init_ctx_wa().
>    */
>   static void
> -add_render_compute_tuning_settings(struct drm_i915_private *i915,
> +add_render_compute_tuning_settings(struct intel_gt *gt,
>   				   struct i915_wa_list *wal)
>   {
> -	if (IS_METEORLAKE(i915) || IS_DG2(i915))
> +	struct drm_i915_private *i915 = gt->i915;
> +
> +	if (IS_GT_IP_RANGE(GFX, gt, IP_VER(12, 70), IP_VER(12, 71)) || IS_DG2(i915))
>   		wa_mcr_write_clr_set(wal, RT_CTRL, STACKID_CTRL, STACKID_CTRL_512);
>   
>   	/*
> @@ -3007,7 +3009,7 @@ general_render_compute_wa_init(struct intel_engine_cs *engine, struct i915_wa_li
>   {
>   	struct drm_i915_private *i915 = engine->i915;
>   
> -	add_render_compute_tuning_settings(i915, wal);
> +	add_render_compute_tuning_settings(engine->gt, wal);
>   
>   	if (GRAPHICS_VER(i915) >= 11) {
>   		/* This is not a Wa (although referred to as
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 682ef2b5c7d5..6bb825d40451 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -431,6 +431,29 @@ static inline struct intel_gt *to_gt(struct drm_i915_private *i915)
>   #define IS_GRAPHICS_VER(i915, from, until) \
>   	(GRAPHICS_VER(i915) >= (from) && GRAPHICS_VER(i915) <= (until))
>   
> +#define __IS_MEDIA_GT(gt) ((gt)->type == GT_MEDIA)
> +#define __IS_GFX_GT(gt) (!__IS_MEDIA_GT(gt))
> +#define __GT_VER_FULL(gt) (__IS_MEDIA_GT(gt) ? \
> +			   MEDIA_VER_FULL((gt)->i915) : \
> +			   GRAPHICS_VER_FULL((gt)->i915))
> +
> +/*
> + * Check that a GT contains IP of the specified type and within the specified
> + * IP range.  E.g.,
> + *
> + *    IS_GT_IP_RANGE(GFX, IP_VER(12, 70), IP_VER(12, 71))
> + *    IS_GT_IP_RANGE(MEDIA, IP_VER(13, 00), IP_VER(18, 02))

I think without the magic GFX/MEDIA first argument would be better and 
more readable. That is simply IS_GT_IP_RANGE(gt, IP_VER(), IP_VER). GT 
type checks feel would be more readable on the outside, and some of them 
will even probably come from a level above. Even when split out on the 
same line it reads more readable to me, like:

   if (IS_MEDIA_GT(gt) && IS_GT_IP_RANGE(gt, IP_VER(), IP_VER())

Regards,

Tvrtko

> + *
> + * Note that media version checks with this macro will only work on platforms
> + * with standalone media design (i.e., media version 13 and higher).
> + */
> +#define IS_GT_IP_RANGE(type, gt, from, until) ( \
> +	BUILD_BUG_ON_ZERO(from < IP_VER(2, 0)) + \
> +	BUILD_BUG_ON_ZERO(until < from) + \
> +	(__IS_##type##_GT(gt) && \
> +	 __GT_VER_FULL(gt) >= (from) && \
> +	 __GT_VER_FULL(gt) <= (until)))
> +
>   #define MEDIA_VER(i915)			(RUNTIME_INFO(i915)->media.ip.ver)
>   #define MEDIA_VER_FULL(i915)		IP_VER(RUNTIME_INFO(i915)->media.ip.ver, \
>   					       RUNTIME_INFO(i915)->media.ip.rel)