[PATCH 3.2 017/131] drm/radeon: fix irq ring buffer overflow handling
From: Ben Hutchings <hidden>
Date: 2014-09-11 12:34:14
Also in:
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3.2.63-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Christian König <christian.koenig@amd.com> commit e8c214d22e76dd0ead38f97f8d2dc09aac70d651 upstream. We must mask out the overflow bit as well, otherwise the wptr will never match the rptr again and the interrupt handler will loop forever. Signed-off-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Michel Dänzer <redacted> [bwh: Backported to 3.2: drop changes for unsupported GPUs] Signed-off-by: Ben Hutchings <redacted> ---
--- a/drivers/gpu/drm/radeon/evergreen.c
+++ b/drivers/gpu/drm/radeon/evergreen.c@@ -2765,6 +2765,7 @@ static u32 evergreen_get_ih_wptr(struct tmp = RREG32(IH_RB_CNTL); tmp |= IH_WPTR_OVERFLOW_CLEAR; WREG32(IH_RB_CNTL, tmp); + wptr &= ~RB_OVERFLOW; } return (wptr & rdev->ih.ptr_mask); } --- a/drivers/gpu/drm/radeon/r600.c +++ b/drivers/gpu/drm/radeon/r600.c
@@ -3280,6 +3280,7 @@ static u32 r600_get_ih_wptr(struct radeo tmp = RREG32(IH_RB_CNTL); tmp |= IH_WPTR_OVERFLOW_CLEAR; WREG32(IH_RB_CNTL, tmp); + wptr &= ~RB_OVERFLOW; } return (wptr & rdev->ih.ptr_mask); }