Re: [PATCH] drm/i915/ilk: special case enabling of PCU_EVENT interrupt

[Oliver Hartkopp <socketcan@hartkopp.net>]

On 26.08.2014 01:24, Jesse Barnes wrote:
> This happens in irq_postinstall before we've set the pm._irqs_disabled flag,
> but shouldn't warn.  So add a nowarn variant to allow this to happen w/o
> a backtrace and keep the rest of the IRQ tracking code happy.
> 
> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

Reported-by: Oliver Hartkopp <socketcan@hartkopp.net>
Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>

Yeah. That fixed it.

Thanks Jesse!

[    2.900147] Linux agpgart interface v0.103
[    2.900475] agpgart-intel 0000:00:00.0: Intel HD Graphics Chipset
[    2.900579] agpgart-intel 0000:00:00.0: detected gtt size: 2097152K total, 262144K mappable
[    2.901354] agpgart-intel 0000:00:00.0: detected 32768K stolen memory
[    2.901743] agpgart-intel 0000:00:00.0: AGP aperture is 256M @ 0xe0000000
[    2.901995] [drm] Initialized drm 1.1.0 20060810
[    2.904212] [drm] Memory usable by graphics device = 2048M
[    2.904295] [drm] Replacing VGA console driver
[    2.904961] Console: switching to colour dummy device 80x25
[    2.937950] i915 0000:00:02.0: irq 24 for MSI/MSI-X
[    2.937962] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[    2.937965] [drm] Driver supports precise vblank timestamp query.
[    2.938310] vgaarb: device changed decodes: PCI:0000:00:02.0,olddecodes=io+mem,decodes=io+mem:owns=io+mem
[    3.030687] fbcon: inteldrmfb (fb0) is primary device
[    3.494467] tsc: Refined TSC clocksource calibration: 2792.999 MHz
[    4.176644] [drm:intel_dp_start_link_train] *ERROR* too many full retries, give up
[    4.495814] Switched to clocksource tsc
[    4.529922] Console: switching to colour frame buffer device 240x67
[    4.536702] i915 0000:00:02.0: fb0: inteldrmfb frame buffer device
[    4.536769] i915 0000:00:02.0: registered panic notifier
[    4.548333] ACPI: Video Device [VID2] (multi-head: yes  rom: no  post: no)
[    4.900233] acpi device:45: registered as cooling_device0
[    4.924178] input: Video Bus as /devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/LNXVIDEO:02/input/input4
[    4.924371] [drm] Initialized i915 1.6.0 20140725 for 0000:00:02.0 on minor 0


Btw. do you know what 

[drm:intel_dp_start_link_train] *ERROR* too many full retries, give up

is about?

Regards,
Oliver

> ---
>  drivers/gpu/drm/i915/i915_irq.c |   18 ++++++++++++------
>  1 files changed, 12 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
> index d5445e7..ec1d9fe 100644
> --- a/drivers/gpu/drm/i915/i915_irq.c
> +++ b/drivers/gpu/drm/i915/i915_irq.c
> @@ -132,6 +132,16 @@ static const u32 hpd_status_i915[] = { /* i915 and valleyview are the same */
>  
>  /* For display hotplug interrupt */
>  static void
> +ironlake_enable_display_irq_nowarn(struct drm_i915_private *dev_priv, u32 mask)
> +{
> +	if ((dev_priv->irq_mask & mask) != 0) {
> +		dev_priv->irq_mask &= ~mask;
> +		I915_WRITE(DEIMR, dev_priv->irq_mask);
> +		POSTING_READ(DEIMR);
> +	}
> +}
> +
> +static void
>  ironlake_enable_display_irq(struct drm_i915_private *dev_priv, u32 mask)
>  {
>  	assert_spin_locked(&dev_priv->irq_lock);
> @@ -139,11 +149,7 @@ ironlake_enable_display_irq(struct drm_i915_private *dev_priv, u32 mask)
>  	if (WARN_ON(!intel_irqs_enabled(dev_priv)))
>  		return;
>  
> -	if ((dev_priv->irq_mask & mask) != 0) {
> -		dev_priv->irq_mask &= ~mask;
> -		I915_WRITE(DEIMR, dev_priv->irq_mask);
> -		POSTING_READ(DEIMR);
> -	}
> +	ironlake_enable_display_irq_nowarn(dev_priv, mask);
>  }
>  
>  static void
> @@ -3665,7 +3671,7 @@ static int ironlake_irq_postinstall(struct drm_device *dev)
>  		 * setup is guaranteed to run in single-threaded context. But we
>  		 * need it to make the assert_spin_locked happy. */
>  		spin_lock_irqsave(&dev_priv->irq_lock, irqflags);
> -		ironlake_enable_display_irq(dev_priv, DE_PCU_EVENT);
> +		ironlake_enable_display_irq_nowarn(dev_priv, DE_PCU_EVENT);
>  		spin_unlock_irqrestore(&dev_priv->irq_lock, irqflags);
>  	}
>  
>