[PATCH] drm/i915: add hotplug activation period to hotplug update mask

Jani Nikula
2015-10-21T14:19:14Z

commit 0706f17c307b056ff6f1848320ba82d76945a6ff
Author: Egbert Eich <eich@suse.de>
Date: Wed Sep 23 16:15:27 2015 +0200

drm/i915: Avoid race of intel_crt_detect_hotplug() with HPD interrupt, v2

added a check with WARN to ensure only bits within the mask are
enabled. Turns out that doesn't hold for G4X, which spits out:

[ 2.641439] ------------[ cut here ]------------
[ 2.641444] WARNING: CPU: 0 PID: 1 at drivers/gpu/drm/i915/i915_irq.c:182 i915_hotplug_interrupt_update_locked+0x45/0x83()
[ 2.641446] WARN_ON(bits & ~mask)
etc.

Add CRT_HOTPLUG_ACTIVATION_PERIOD_64 to the mask to fix the warning.

Reported-by: Oleksij Rempel <linux@rempel-privat.de>
References: https://bugzilla.kernel.org/show_bug.cgi?id=104991
Fixes: 0706f17c307b ("drm/i915: Avoid race of intel_crt_detect_hotplug() with HPD interrupt, v2")
Cc: Egbert Eich <eich@suse.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
---
drivers/gpu/drm/i915/i915_irq.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 7f91f74961f4..5b9f63d4318b 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -4236,9 +4236,10 @@ static void i915_hpd_irq_setup(struct drm_device *dev)

/* Ignore TV since it's buggy */
i915_hotplug_interrupt_update_locked(dev_priv,
- (HOTPLUG_INT_EN_MASK
- | CRT_HOTPLUG_VOLTAGE_COMPARE_MASK),
- hotplug_en);
+ HOTPLUG_INT_EN_MASK |
+ CRT_HOTPLUG_VOLTAGE_COMPARE_MASK |
+ CRT_HOTPLUG_ACTIVATION_PERIOD_64,
+ hotplug_en);
}

static irqreturn_t i965_irq_handler(int irq, void *arg)
--
2.1.4