Re: [PATCH v2] drm/i915: Fix to Enable GT/PM Interrupts for cherryview.

[Daniel Vetter <daniel@ffwll.ch>]

On Fri, Aug 29, 2014 at 08:45:21AM +0530, Deepak S wrote:
> 
> On Tuesday 26 August 2014 07:24 PM, Daniel Vetter wrote:
> >On Fri, Aug 22, 2014 at 08:32:40AM +0530, deepak.s@linux.intel.com wrote:
> >>From: Deepak S <deepak.s@linux.intel.com>
> >>
> >>Programing GT IER interrupts was fumbled while enabling Interrupts for
> >>gen8
> >>
> >>This is a regression from
> >>     commit abd58f0175915bed644aa67c8f69dc571b8280e0
> >>     Author: Ben Widawsky <benjamin.widawsky@intel.com>
> >>     Date:   Sat Nov 2 21:07:09 2013 -0700
> >>
> >>	drm/i915/bdw: Implement interrupt changes
> >_Really_ unlikely that this is a regression from this commit, since that
> >introduced all the gen8 interrupt handling in the first place. I think
> >this is because of the reworked interrupt handling over gpu resets, where
> >we want to keep rps interrupts enabled. But I'm not terribly sure.
> >
> >I think a more convincing story is that this is an oversight from
> >
> >commit a6706b45a57a23a613b34793e1414991b60a09c1
> >Author: Deepak S <deepak.s@linux.intel.com>
> >Date:   Sat Mar 15 20:23:22 2014 +0530
> >
> >     drm/i915: Track the enabled PM interrupts in dev_priv
> >
> >or more precisely (since chv wasn't public back then iirc) we forgot to
> >add the corresponding patch to -internal.
> >
> >In any case please clarify the commit message and please also add a few
> >words about why exactly we need this - I had to dig through git history to
> >figure this all out.
> >
> >I've applied the patch already, so you can just reply with the revised
> >commit message that I should put in.
> >
> >Thanks, Daniel
> 
> Daniel, This patch is not just for chv right. it affects the gen8(BDW).
> Your right we might have missed in (drm/i915: Track the enabled PM interrupts in dev_priv).
> In -internal, for chv, We used to program the IER in enable_interrupts routing so it was already taken care.
> After the interrupt re-work, we are supposed to add IER in post_irq handler which we missed it.
> 
> New commit msg:  Is this fine? Do i need to resubmit the patch?

Yeah fine and thanks for confirming. I've adjusted the commit message.
-Daniel

> ------------------------------------------------------------------
> 
> Programing GT IER interrupts was fumbled while enabling Interrupts for
> gen8
> 
> We forgot to program PM IER interrupt in gen8_gt_irq_postinstall based on the new  re-worked interrupt
> routines.
> 
> >>v2: Kill the loop and init GT interrupts (Ville)
> >>
> >>Signed-off-by: Deepak S <deepak.s@linux.intel.com>
> >>---
> >>  drivers/gpu/drm/i915/i915_irq.c | 9 ++++-----
> >>  1 file changed, 4 insertions(+), 5 deletions(-)
> >>
> >>diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
> >>index d5445e7..c33cf89 100644
> >>--- a/drivers/gpu/drm/i915/i915_irq.c
> >>+++ b/drivers/gpu/drm/i915/i915_irq.c
> >>@@ -3799,8 +3799,6 @@ static int valleyview_irq_postinstall(struct drm_device *dev)
> >>  static void gen8_gt_irq_postinstall(struct drm_i915_private *dev_priv)
> >>  {
> >>-	int i;
> >>-
> >>  	/* These are interrupts we'll toggle with the ring mask register */
> >>  	uint32_t gt_interrupts[] = {
> >>  		GT_RENDER_USER_INTERRUPT << GEN8_RCS_IRQ_SHIFT |
> >>@@ -3817,10 +3815,11 @@ static void gen8_gt_irq_postinstall(struct drm_i915_private *dev_priv)
> >>  			GT_CONTEXT_SWITCH_INTERRUPT << GEN8_VECS_IRQ_SHIFT
> >>  		};
> >>-	for (i = 0; i < ARRAY_SIZE(gt_interrupts); i++)
> >>-		GEN8_IRQ_INIT_NDX(GT, i, ~gt_interrupts[i], gt_interrupts[i]);
> >>-
> >>  	dev_priv->pm_irq_mask = 0xffffffff;
> >>+	GEN8_IRQ_INIT_NDX(GT, 0, ~gt_interrupts[0], gt_interrupts[0]);
> >>+	GEN8_IRQ_INIT_NDX(GT, 1, ~gt_interrupts[1], gt_interrupts[1]);
> >>+	GEN8_IRQ_INIT_NDX(GT, 2, dev_priv->pm_irq_mask, dev_priv->pm_rps_events);
> >>+	GEN8_IRQ_INIT_NDX(GT, 3, ~gt_interrupts[3], gt_interrupts[3]);
> >>  }
> >>  static void gen8_de_irq_postinstall(struct drm_i915_private *dev_priv)
> >>-- 
> >>1.9.1
> >>
> >>_______________________________________________
> >>Intel-gfx mailing list
> >>Intel-gfx@lists.freedesktop.org
> >>http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch