Re: [Intel-gfx] [PATCH v2] drm/i915: Make IRQ reset and postinstall multi-gt aware

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

On 13/04/2023 10:20, Andi Shyti wrote:
> From: Paulo Zanoni <paulo.r.zanoni@intel.com>
> 
> In multitile systems IRQ need to be reset and enabled per GT.
> 
> Although in MTL the GUnit misc interrupts register set are
> available only in GT-0, we need to loop through all the GT's
> in order to initialize the media engine which lies on a different
> GT.
> 
> Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
> Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
> ---
> Hi,
> 
> proposing again this patch, apparently GuC needs this patch to
> initialize the media GT.

What is the resolution for Matt's concern that this is wrong for MTL?

Regards,

Tvrtko

> Changelog
> =========
> v1 -> v2
>   - improve description in the commit log.
> 
>   drivers/gpu/drm/i915/i915_irq.c | 28 ++++++++++++++++++----------
>   1 file changed, 18 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
> index d24bdea65a3dc..524d64bf5d186 100644
> --- a/drivers/gpu/drm/i915/i915_irq.c
> +++ b/drivers/gpu/drm/i915/i915_irq.c
> @@ -2764,14 +2764,19 @@ static void dg1_irq_reset(struct drm_i915_private *dev_priv)
>   {
>   	struct intel_gt *gt = to_gt(dev_priv);
>   	struct intel_uncore *uncore = gt->uncore;
> +	unsigned int i;
>   
>   	dg1_master_intr_disable(dev_priv->uncore.regs);
>   
> -	gen11_gt_irq_reset(gt);
> -	gen11_display_irq_reset(dev_priv);
> +	for_each_gt(gt, dev_priv, i) {
> +		gen11_gt_irq_reset(gt);
>   
> -	GEN3_IRQ_RESET(uncore, GEN11_GU_MISC_);
> -	GEN3_IRQ_RESET(uncore, GEN8_PCU_);
> +		uncore = gt->uncore;
> +		GEN3_IRQ_RESET(uncore, GEN11_GU_MISC_);
> +		GEN3_IRQ_RESET(uncore, GEN8_PCU_);
> +	}
> +
> +	gen11_display_irq_reset(dev_priv);
>   }
>   
>   void gen8_irq_power_well_post_enable(struct drm_i915_private *dev_priv,
> @@ -3425,13 +3430,16 @@ static void gen11_irq_postinstall(struct drm_i915_private *dev_priv)
>   
>   static void dg1_irq_postinstall(struct drm_i915_private *dev_priv)
>   {
> -	struct intel_gt *gt = to_gt(dev_priv);
> -	struct intel_uncore *uncore = gt->uncore;
>   	u32 gu_misc_masked = GEN11_GU_MISC_GSE;
> +	struct intel_gt *gt;
> +	unsigned int i;
>   
> -	gen11_gt_irq_postinstall(gt);
> +	for_each_gt(gt, dev_priv, i) {
> +		gen11_gt_irq_postinstall(gt);
>   
> -	GEN3_IRQ_INIT(uncore, GEN11_GU_MISC_, ~gu_misc_masked, gu_misc_masked);
> +		GEN3_IRQ_INIT(gt->uncore, GEN11_GU_MISC_, ~gu_misc_masked,
> +			      gu_misc_masked);
> +	}
>   
>   	if (HAS_DISPLAY(dev_priv)) {
>   		icp_irq_postinstall(dev_priv);
> @@ -3440,8 +3448,8 @@ static void dg1_irq_postinstall(struct drm_i915_private *dev_priv)
>   				   GEN11_DISPLAY_IRQ_ENABLE);
>   	}
>   
> -	dg1_master_intr_enable(uncore->regs);
> -	intel_uncore_posting_read(uncore, DG1_MSTR_TILE_INTR);
> +	dg1_master_intr_enable(to_gt(dev_priv)->uncore->regs);
> +	intel_uncore_posting_read(to_gt(dev_priv)->uncore, DG1_MSTR_TILE_INTR);
>   }
>   
>   static void cherryview_irq_postinstall(struct drm_i915_private *dev_priv)