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| author | Christian Koenig <christian.koenig@amd.com> | 2012-05-16 21:45:24 +0200 |
|---|---|---|
| committer | Christian König <deathsimple@vodafone.de> | 2012-06-21 09:38:48 +0200 |
| commit | c20dc3698dc7ecf053e2bf77299ae5982c0c2c45 (patch) | |
| tree | e150268483bee4137d9c22e3121171b23a53be76 /drivers/gpu/drm/radeon/evergreen.c | |
| parent | 6823d74003abedd688a3f535aefe6ce0e06444fd (diff) | |
| download | linux-3.10-c20dc3698dc7ecf053e2bf77299ae5982c0c2c45.tar.gz linux-3.10-c20dc3698dc7ecf053e2bf77299ae5982c0c2c45.tar.bz2 linux-3.10-c20dc3698dc7ecf053e2bf77299ae5982c0c2c45.zip | |
drm/radeon: fix & improve ih ring handling v3
The spinlock was actually there to protect the
rptr, but rptr was read outside of the locked area.
Also we don't really need a spinlock here, an
atomic should to quite fine since we only need to
prevent it from being reentrant.
v2: Keep the spinlock....
v3: Back to an atomic again after finding & fixing the real bug.
Signed-off-by: Christian Koenig <christian.koenig@amd.com>
Diffstat (limited to 'drivers/gpu/drm/radeon/evergreen.c')
| -rw-r--r-- | drivers/gpu/drm/radeon/evergreen.c | 26 |
1 files changed, 13 insertions, 13 deletions
diff --git a/drivers/gpu/drm/radeon/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c index 8e40ba4a9b7..765bd1f2e1c 100644 --- a/drivers/gpu/drm/radeon/evergreen.c +++ b/drivers/gpu/drm/radeon/evergreen.c @@ -2676,7 +2676,6 @@ int evergreen_irq_process(struct radeon_device *rdev) u32 rptr; u32 src_id, src_data; u32 ring_index; - unsigned long flags; bool queue_hotplug = false; bool queue_hdmi = false; @@ -2684,22 +2683,21 @@ int evergreen_irq_process(struct radeon_device *rdev) return IRQ_NONE; wptr = evergreen_get_ih_wptr(rdev); + +restart_ih: + /* is somebody else already processing irqs? */ + if (atomic_xchg(&rdev->ih.lock, 1)) + return IRQ_NONE; + rptr = rdev->ih.rptr; DRM_DEBUG("r600_irq_process start: rptr %d, wptr %d\n", rptr, wptr); - spin_lock_irqsave(&rdev->ih.lock, flags); - if (rptr == wptr) { - spin_unlock_irqrestore(&rdev->ih.lock, flags); - return IRQ_NONE; - } -restart_ih: /* Order reading of wptr vs. reading of IH ring data */ rmb(); /* display interrupts */ evergreen_irq_ack(rdev); - rdev->ih.wptr = wptr; while (rptr != wptr) { /* wptr/rptr are in bytes! */ ring_index = rptr / 4; @@ -2998,17 +2996,19 @@ restart_ih: rptr += 16; rptr &= rdev->ih.ptr_mask; } - /* make sure wptr hasn't changed while processing */ - wptr = evergreen_get_ih_wptr(rdev); - if (wptr != rdev->ih.wptr) - goto restart_ih; if (queue_hotplug) schedule_work(&rdev->hotplug_work); if (queue_hdmi) schedule_work(&rdev->audio_work); rdev->ih.rptr = rptr; WREG32(IH_RB_RPTR, rdev->ih.rptr); - spin_unlock_irqrestore(&rdev->ih.lock, flags); + atomic_set(&rdev->ih.lock, 0); + + /* make sure wptr hasn't changed while processing */ + wptr = evergreen_get_ih_wptr(rdev); + if (wptr != rptr) + goto restart_ih; + return IRQ_HANDLED; } |