drm/radeon: Clear RB_OVERFLOW bit earlier

Otherwise the bit remains set in rdev->ih.rptr, so the wptr can never
match that and we still have an infinite loop.

This fix allows me to successfully recover from an IH ring buffer
overflow.

Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/radeon/cik.c b/drivers/gpu/drm/radeon/cik.c
index fa95659..620e894 100644 (file)
--- a/drivers/gpu/drm/radeon/cik.c
+++ b/drivers/gpu/drm/radeon/cik.c
@@ -7751,6 +7751,7 @@ static inline u32 cik_get_ih_wptr(struct radeon_device *rdev)
                wptr = RREG32(IH_RB_WPTR);
 
        if (wptr & RB_OVERFLOW) {
+               wptr &= ~RB_OVERFLOW;
                /* When a ring buffer overflow happen start parsing interrupt
                 * from the last not overwritten vector (wptr + 16). Hopefully
                 * this should allow us to catchup.
@@ -7761,7 +7762,6 @@ static inline u32 cik_get_ih_wptr(struct radeon_device *rdev)
                tmp = RREG32(IH_RB_CNTL);
                tmp |= IH_WPTR_OVERFLOW_CLEAR;
                WREG32(IH_RB_CNTL, tmp);
-               wptr &= ~RB_OVERFLOW;
        }
        return (wptr & rdev->ih.ptr_mask);
 }

diff --git a/drivers/gpu/drm/radeon/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c
index dbca60c..6a50b03 100644 (file)
--- a/drivers/gpu/drm/radeon/evergreen.c
+++ b/drivers/gpu/drm/radeon/evergreen.c
@@ -4749,6 +4749,7 @@ static u32 evergreen_get_ih_wptr(struct radeon_device *rdev)
                wptr = RREG32(IH_RB_WPTR);
 
        if (wptr & RB_OVERFLOW) {
+               wptr &= ~RB_OVERFLOW;
                /* When a ring buffer overflow happen start parsing interrupt
                 * from the last not overwritten vector (wptr + 16). Hopefully
                 * this should allow us to catchup.
@@ -4759,7 +4760,6 @@ static u32 evergreen_get_ih_wptr(struct radeon_device *rdev)
                tmp = RREG32(IH_RB_CNTL);
                tmp |= IH_WPTR_OVERFLOW_CLEAR;
                WREG32(IH_RB_CNTL, tmp);
-               wptr &= ~RB_OVERFLOW;
        }
        return (wptr & rdev->ih.ptr_mask);
 }

diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index 3cfb500..5514f1b 100644 (file)
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -3792,6 +3792,7 @@ static u32 r600_get_ih_wptr(struct radeon_device *rdev)
                wptr = RREG32(IH_RB_WPTR);
 
        if (wptr & RB_OVERFLOW) {
+               wptr &= ~RB_OVERFLOW;
                /* When a ring buffer overflow happen start parsing interrupt
                 * from the last not overwritten vector (wptr + 16). Hopefully
                 * this should allow us to catchup.
@@ -3802,7 +3803,6 @@ static u32 r600_get_ih_wptr(struct radeon_device *rdev)
                tmp = RREG32(IH_RB_CNTL);
                tmp |= IH_WPTR_OVERFLOW_CLEAR;
                WREG32(IH_RB_CNTL, tmp);
-               wptr &= ~RB_OVERFLOW;
        }
        return (wptr & rdev->ih.ptr_mask);
 }

diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c
index 6bce408..eacbe8a 100644 (file)
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -6316,6 +6316,7 @@ static inline u32 si_get_ih_wptr(struct radeon_device *rdev)
                wptr = RREG32(IH_RB_WPTR);
 
        if (wptr & RB_OVERFLOW) {
+               wptr &= ~RB_OVERFLOW;
                /* When a ring buffer overflow happen start parsing interrupt
                 * from the last not overwritten vector (wptr + 16). Hopefully
                 * this should allow us to catchup.
@@ -6326,7 +6327,6 @@ static inline u32 si_get_ih_wptr(struct radeon_device *rdev)
                tmp = RREG32(IH_RB_CNTL);
                tmp |= IH_WPTR_OVERFLOW_CLEAR;
                WREG32(IH_RB_CNTL, tmp);
-               wptr &= ~RB_OVERFLOW;
        }
        return (wptr & rdev->ih.ptr_mask);
 }