[PATCH] drm/i915/mtl: Add MC6 Wa_14017210380 for SAMedia

Matt Roper matthew.d.roper at intel.com
Tue Nov 1 15:17:35 UTC 2022


On Sat, Oct 29, 2022 at 12:59:35AM +0530, Badal Nilawar wrote:
> This workaround is added for Media Tile of MTL A step. It is to help
> pcode workaround which handles the hardware bug seen on CXL splitter
> during package C2/C3 transitins due to MC6 entry/exit. As a part of
> workaround pcode expect kmd to send mailbox message "media busy" when
> components of Media tile is in use and "media not busy" when not in use.
> As per workaround description gucrc need to be disabled so enabled
> host based RC for Media tile.
> 
> HSD: 14017210380
> 
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> Cc: Radhakrishna Sripada <radhakrishna.sripada at intel.com>
> Cc: Vinay Belgaumkar <vinay.belgaumkar at intel.com>
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Signed-off-by: Badal Nilawar <badal.nilawar at intel.com>
> ---
>  drivers/gpu/drm/i915/gt/intel_gt_pm.c     | 33 +++++++++++++++++++++++
>  drivers/gpu/drm/i915/gt/uc/intel_guc_rc.c | 13 ++++++++-
>  drivers/gpu/drm/i915/i915_drv.h           |  4 +++
>  drivers/gpu/drm/i915/i915_reg.h           |  9 +++++++
>  4 files changed, 58 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/gt/intel_gt_pm.c b/drivers/gpu/drm/i915/gt/intel_gt_pm.c
> index f553e2173bda..398dbeb298ca 100644
> --- a/drivers/gpu/drm/i915/gt/intel_gt_pm.c
> +++ b/drivers/gpu/drm/i915/gt/intel_gt_pm.c
> @@ -19,10 +19,37 @@
>  #include "intel_rc6.h"
>  #include "intel_rps.h"
>  #include "intel_wakeref.h"
> +#include "intel_pcode.h"
>  #include "pxp/intel_pxp_pm.h"
>  
>  #define I915_GT_SUSPEND_IDLE_TIMEOUT (HZ / 2)
>  
> +/*
> + * Wa_14017210380: mtl
> + */

This doesn't appear to be a valid workaround number; workaround numbers
are always supposed to be the "lineage" numbers from the workaround
database.  Wa_14017073508 seems to be related; is that the one you're
implementing?

> +
> +static bool mtl_needs_media_mc6_wa(struct intel_gt *gt)

Drive-by comment:  names like this aren't great since even though
there's only one "media MC6" workaround today, that may not be true in
the future.


Matt

> +{
> +	return (IS_MTL_GRAPHICS_STEP(gt->i915, P, STEP_A0, STEP_B0) &&
> +		gt->type == GT_MEDIA);
> +}
> +
> +static void mtl_mc6_wa_media_busy(struct intel_gt *gt)
> +{
> +	if (mtl_needs_media_mc6_wa(gt))
> +		snb_pcode_write_p(gt->uncore, PCODE_MBOX_GT_STATE,
> +				  PCODE_MBOX_GT_STATE_MEDIA_BUSY,
> +				  PCODE_MBOX_GT_STATE_DOMAIN_MEDIA, 0);
> +}
> +
> +static void mtl_mc6_wa_media_not_busy(struct intel_gt *gt)
> +{
> +	if (mtl_needs_media_mc6_wa(gt))
> +		snb_pcode_write_p(gt->uncore, PCODE_MBOX_GT_STATE,
> +				  PCODE_MBOX_GT_STATE_MEDIA_NOT_BUSY,
> +				  PCODE_MBOX_GT_STATE_DOMAIN_MEDIA, 0);
> +}
> +
>  static void user_forcewake(struct intel_gt *gt, bool suspend)
>  {
>  	int count = atomic_read(&gt->user_wakeref);
> @@ -70,6 +97,9 @@ static int __gt_unpark(struct intel_wakeref *wf)
>  
>  	GT_TRACE(gt, "\n");
>  
> +	/* Wa_14017210380: mtl */
> +	mtl_mc6_wa_media_busy(gt);
> +
>  	/*
>  	 * It seems that the DMC likes to transition between the DC states a lot
>  	 * when there are no connected displays (no active power domains) during
> @@ -119,6 +149,9 @@ static int __gt_park(struct intel_wakeref *wf)
>  	GEM_BUG_ON(!wakeref);
>  	intel_display_power_put_async(i915, POWER_DOMAIN_GT_IRQ, wakeref);
>  
> +	/* Wa_14017210380: mtl */
> +	mtl_mc6_wa_media_not_busy(gt);
> +
>  	return 0;
>  }
>  
> diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_rc.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_rc.c
> index 8f8dd05835c5..cc6356ff84a5 100644
> --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_rc.c
> +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_rc.c
> @@ -11,9 +11,20 @@
>  
>  static bool __guc_rc_supported(struct intel_guc *guc)
>  {
> +	struct intel_gt *gt = guc_to_gt(guc);
> +
> +	/*
> +	 * Wa_14017210380: mtl
> +	 * Do not enable gucrc to avoid additional interrupts which
> +	 * may disrupt pcode wa.
> +	 */
> +	if (IS_MTL_GRAPHICS_STEP(gt->i915, P, STEP_A0, STEP_B0) &&
> +	    gt->type == GT_MEDIA)
> +		return false;
> +
>  	/* GuC RC is unavailable for pre-Gen12 */
>  	return guc->submission_supported &&
> -		GRAPHICS_VER(guc_to_gt(guc)->i915) >= 12;
> +		GRAPHICS_VER(gt->i915) >= 12;
>  }
>  
>  static bool __guc_rc_selected(struct intel_guc *guc)
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 05b3300cc4ed..659b92382ff2 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -740,6 +740,10 @@ IS_SUBPLATFORM(const struct drm_i915_private *i915,
>  #define IS_XEHPSDV_GRAPHICS_STEP(__i915, since, until) \
>  	(IS_XEHPSDV(__i915) && IS_GRAPHICS_STEP(__i915, since, until))
>  
> +#define IS_MTL_GRAPHICS_STEP(__i915, variant, since, until) \
> +	(IS_SUBPLATFORM(__i915, INTEL_METEORLAKE, INTEL_SUBPLATFORM_##variant) && \
> +	 IS_GRAPHICS_STEP(__i915, since, until))
> +
>  /*
>   * DG2 hardware steppings are a bit unusual.  The hardware design was forked to
>   * create three variants (G10, G11, and G12) which each have distinct
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index 1c0da50c0dc7..abe62cea083d 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -6678,6 +6678,15 @@
>  /*   XEHP_PCODE_FREQUENCY_CONFIG param2 */
>  #define     PCODE_MBOX_DOMAIN_NONE		0x0
>  #define     PCODE_MBOX_DOMAIN_MEDIAFF		0x3
> +
> +/* Wa_14017210380: mtl */
> +#define   PCODE_MBOX_GT_STATE			0x50
> +/* sub-commands (param1) */
> +#define     PCODE_MBOX_GT_STATE_MEDIA_BUSY	0x1
> +#define     PCODE_MBOX_GT_STATE_MEDIA_NOT_BUSY	0x2
> +/* param2 */
> +#define     PCODE_MBOX_GT_STATE_DOMAIN_MEDIA	0x1
> +
>  #define GEN6_PCODE_DATA				_MMIO(0x138128)
>  #define   GEN6_PCODE_FREQ_IA_RATIO_SHIFT	8
>  #define   GEN6_PCODE_FREQ_RING_RATIO_SHIFT	16
> -- 
> 2.25.1
> 

-- 
Matt Roper
Graphics Software Engineer
VTT-OSGC Platform Enablement
Intel Corporation


More information about the dri-devel mailing list