* [PATCH 1/4] drm/i915: Disable LP1+ watermarks on Lenovo Thinkpad T431s
@ 2019-02-22 15:52 Ville Syrjala
2019-02-25 13:19 ` [Intel-gfx] " Jani Nikula
0 siblings, 1 reply; 2+ messages in thread
From: Ville Syrjala @ 2019-02-22 15:52 UTC (permalink / raw)
To: intel-gfx; +Cc: stable, Andrea
From: Ville Syrjälä <ville.syrjala@linux.intel.com>
Lenovo Thinkpad T431s (ivb) apparently can't handle LP1+ watermarks
being enabled. It underruns severly enough that the screen is
unusable. The latency values and watemarks look as expected.
And sadly updating the BIOS to the latest version (BIOS GHET41WW
(1.26 ) 11/21/2018) did not help.
One glimmer of hope I had was the VBT. It seems to have some sort
of flag for "self refresh = yes/no", but when I looked at a bunch
of VBTs I had lying around most of them had that field set to "no".
So if we used that we'd end up disabling LP1+ on most machines.
That seems a bit harsh since we know LP1+ works just fine on
most machines.
Since I have no better ideas let's just disable LP1+ watermarks
on this particular machine via a quirk.
Cc: stable@vger.kernel.org
Cc: Andrea <andreatclist@gmail.com>
Reported-by: Andrea <andreatclist@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=109477
Fixes: a46a7350b1e8 ("drm/i915: Fix ilk+ watermarks when disabling pipes")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
drivers/gpu/drm/i915/intel_pm.c | 51 +++++++++++++++++++++++++--------
1 file changed, 39 insertions(+), 12 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 4c0e43caa5cd..75dceac19950 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -3015,6 +3015,29 @@ static void snb_wm_latency_quirk(struct drm_i915_private *dev_priv)
intel_print_wm_latency(dev_priv, "Cursor", dev_priv->wm.cur_latency);
}
+static void ilk_wm_disable_quirk(struct drm_i915_private *dev_priv,
+ int level)
+{
+ int max_level = ilk_wm_max_level(dev_priv);
+
+ if (dev_priv->wm.pri_latency[level] == 0 &&
+ dev_priv->wm.spr_latency[level] == 0 &&
+ dev_priv->wm.cur_latency[level] == 0)
+ return;
+
+ DRM_DEBUG_KMS("LP%d+ watermarks disabled by quirk\n", level);
+
+ for (; level <= max_level; level++) {
+ dev_priv->wm.pri_latency[level] = 0;
+ dev_priv->wm.spr_latency[level] = 0;
+ dev_priv->wm.cur_latency[level] = 0;
+ }
+
+ intel_print_wm_latency(dev_priv, "Primary", dev_priv->wm.pri_latency);
+ intel_print_wm_latency(dev_priv, "Sprite", dev_priv->wm.spr_latency);
+ intel_print_wm_latency(dev_priv, "Cursor", dev_priv->wm.cur_latency);
+}
+
static void snb_wm_lp3_irq_quirk(struct drm_i915_private *dev_priv)
{
/*
@@ -3028,23 +3051,18 @@ static void snb_wm_lp3_irq_quirk(struct drm_i915_private *dev_priv)
* interrupts only. To play it safe we disable LP3
* watermarks entirely.
*/
- if (dev_priv->wm.pri_latency[3] == 0 &&
- dev_priv->wm.spr_latency[3] == 0 &&
- dev_priv->wm.cur_latency[3] == 0)
- return;
-
- dev_priv->wm.pri_latency[3] = 0;
- dev_priv->wm.spr_latency[3] = 0;
- dev_priv->wm.cur_latency[3] = 0;
+ ilk_wm_disable_quirk(dev_priv, 3);
+}
- DRM_DEBUG_KMS("LP3 watermarks disabled due to potential for lost interrupts\n");
- intel_print_wm_latency(dev_priv, "Primary", dev_priv->wm.pri_latency);
- intel_print_wm_latency(dev_priv, "Sprite", dev_priv->wm.spr_latency);
- intel_print_wm_latency(dev_priv, "Cursor", dev_priv->wm.cur_latency);
+static void ilk_wm_disable_lp1_quirk(struct drm_i915_private *dev_priv)
+{
+ ilk_wm_disable_quirk(dev_priv, 1);
}
static void ilk_setup_wm_latency(struct drm_i915_private *dev_priv)
{
+ struct pci_dev *pdev = dev_priv->drm.pdev;
+
intel_read_wm_latency(dev_priv, dev_priv->wm.pri_latency);
memcpy(dev_priv->wm.spr_latency, dev_priv->wm.pri_latency,
@@ -3063,6 +3081,15 @@ static void ilk_setup_wm_latency(struct drm_i915_private *dev_priv)
snb_wm_latency_quirk(dev_priv);
snb_wm_lp3_irq_quirk(dev_priv);
}
+
+ /*
+ * Lenovo Thinkpad T431s (ivb)
+ * Massive underruns.
+ */
+ if (pdev->device == 0x0166 &&
+ pdev->subsystem_vendor == 0x17aa &&
+ pdev->subsystem_device == 0x2208)
+ ilk_wm_disable_lp1_quirk(dev_priv);
}
static void skl_setup_wm_latency(struct drm_i915_private *dev_priv)
--
2.19.2
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [Intel-gfx] [PATCH 1/4] drm/i915: Disable LP1+ watermarks on Lenovo Thinkpad T431s
2019-02-22 15:52 [PATCH 1/4] drm/i915: Disable LP1+ watermarks on Lenovo Thinkpad T431s Ville Syrjala
@ 2019-02-25 13:19 ` Jani Nikula
0 siblings, 0 replies; 2+ messages in thread
From: Jani Nikula @ 2019-02-25 13:19 UTC (permalink / raw)
To: Ville Syrjala, intel-gfx; +Cc: Andrea, stable
On Fri, 22 Feb 2019, Ville Syrjala <ville.syrjala@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> Lenovo Thinkpad T431s (ivb) apparently can't handle LP1+ watermarks
> being enabled. It underruns severly enough that the screen is
> unusable. The latency values and watemarks look as expected.
> And sadly updating the BIOS to the latest version (BIOS GHET41WW
> (1.26 ) 11/21/2018) did not help.
>
> One glimmer of hope I had was the VBT. It seems to have some sort
> of flag for "self refresh = yes/no", but when I looked at a bunch
> of VBTs I had lying around most of them had that field set to "no".
> So if we used that we'd end up disabling LP1+ on most machines.
> That seems a bit harsh since we know LP1+ works just fine on
> most machines.
>
> Since I have no better ideas let's just disable LP1+ watermarks
> on this particular machine via a quirk.
>
> Cc: stable@vger.kernel.org
> Cc: Andrea <andreatclist@gmail.com>
> Reported-by: Andrea <andreatclist@gmail.com>
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=109477
> Fixes: a46a7350b1e8 ("drm/i915: Fix ilk+ watermarks when disabling pipes")
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Does what it says on the box, though I'm saddened we have to resort to a
quirk.
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
> ---
> drivers/gpu/drm/i915/intel_pm.c | 51 +++++++++++++++++++++++++--------
> 1 file changed, 39 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index 4c0e43caa5cd..75dceac19950 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -3015,6 +3015,29 @@ static void snb_wm_latency_quirk(struct drm_i915_private *dev_priv)
> intel_print_wm_latency(dev_priv, "Cursor", dev_priv->wm.cur_latency);
> }
>
> +static void ilk_wm_disable_quirk(struct drm_i915_private *dev_priv,
> + int level)
> +{
> + int max_level = ilk_wm_max_level(dev_priv);
> +
> + if (dev_priv->wm.pri_latency[level] == 0 &&
> + dev_priv->wm.spr_latency[level] == 0 &&
> + dev_priv->wm.cur_latency[level] == 0)
> + return;
> +
> + DRM_DEBUG_KMS("LP%d+ watermarks disabled by quirk\n", level);
> +
> + for (; level <= max_level; level++) {
> + dev_priv->wm.pri_latency[level] = 0;
> + dev_priv->wm.spr_latency[level] = 0;
> + dev_priv->wm.cur_latency[level] = 0;
> + }
> +
> + intel_print_wm_latency(dev_priv, "Primary", dev_priv->wm.pri_latency);
> + intel_print_wm_latency(dev_priv, "Sprite", dev_priv->wm.spr_latency);
> + intel_print_wm_latency(dev_priv, "Cursor", dev_priv->wm.cur_latency);
> +}
> +
> static void snb_wm_lp3_irq_quirk(struct drm_i915_private *dev_priv)
> {
> /*
> @@ -3028,23 +3051,18 @@ static void snb_wm_lp3_irq_quirk(struct drm_i915_private *dev_priv)
> * interrupts only. To play it safe we disable LP3
> * watermarks entirely.
> */
> - if (dev_priv->wm.pri_latency[3] == 0 &&
> - dev_priv->wm.spr_latency[3] == 0 &&
> - dev_priv->wm.cur_latency[3] == 0)
> - return;
> -
> - dev_priv->wm.pri_latency[3] = 0;
> - dev_priv->wm.spr_latency[3] = 0;
> - dev_priv->wm.cur_latency[3] = 0;
> + ilk_wm_disable_quirk(dev_priv, 3);
> +}
>
> - DRM_DEBUG_KMS("LP3 watermarks disabled due to potential for lost interrupts\n");
> - intel_print_wm_latency(dev_priv, "Primary", dev_priv->wm.pri_latency);
> - intel_print_wm_latency(dev_priv, "Sprite", dev_priv->wm.spr_latency);
> - intel_print_wm_latency(dev_priv, "Cursor", dev_priv->wm.cur_latency);
> +static void ilk_wm_disable_lp1_quirk(struct drm_i915_private *dev_priv)
> +{
> + ilk_wm_disable_quirk(dev_priv, 1);
> }
>
> static void ilk_setup_wm_latency(struct drm_i915_private *dev_priv)
> {
> + struct pci_dev *pdev = dev_priv->drm.pdev;
> +
> intel_read_wm_latency(dev_priv, dev_priv->wm.pri_latency);
>
> memcpy(dev_priv->wm.spr_latency, dev_priv->wm.pri_latency,
> @@ -3063,6 +3081,15 @@ static void ilk_setup_wm_latency(struct drm_i915_private *dev_priv)
> snb_wm_latency_quirk(dev_priv);
> snb_wm_lp3_irq_quirk(dev_priv);
> }
> +
> + /*
> + * Lenovo Thinkpad T431s (ivb)
> + * Massive underruns.
> + */
> + if (pdev->device == 0x0166 &&
> + pdev->subsystem_vendor == 0x17aa &&
> + pdev->subsystem_device == 0x2208)
> + ilk_wm_disable_lp1_quirk(dev_priv);
> }
>
> static void skl_setup_wm_latency(struct drm_i915_private *dev_priv)
--
Jani Nikula, Intel Open Source Graphics Center
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2019-02-25 13:17 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2019-02-22 15:52 [PATCH 1/4] drm/i915: Disable LP1+ watermarks on Lenovo Thinkpad T431s Ville Syrjala
2019-02-25 13:19 ` [Intel-gfx] " Jani Nikula
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).