drm/radeon/kms: add some loop timeouts in pageflip code

Avoid infinite loops waiting for surface updates if a GPU
reset happens while waiting for a page flip.

See:
https://bugs.freedesktop.org/show_bug.cgi?id=43191

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@kernel.org
Reviewed-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de>
Tested-by: Simon Farnsworth <simon.farnsworth@onelan.co.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>

diff --git a/drivers/gpu/drm/radeon/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c
index 1d603a3..5e00d16 100644 (file)
--- a/drivers/gpu/drm/radeon/evergreen.c
+++ b/drivers/gpu/drm/radeon/evergreen.c
@@ -82,6 +82,7 @@ u32 evergreen_page_flip(struct radeon_device *rdev, int crtc_id, u64 crtc_base)
 {
        struct radeon_crtc *radeon_crtc = rdev->mode_info.crtcs[crtc_id];
        u32 tmp = RREG32(EVERGREEN_GRPH_UPDATE + radeon_crtc->crtc_offset);
+       int i;
 
        /* Lock the graphics update lock */
        tmp |= EVERGREEN_GRPH_UPDATE_LOCK;
@@ -99,7 +100,11 @@ u32 evergreen_page_flip(struct radeon_device *rdev, int crtc_id, u64 crtc_base)
               (u32)crtc_base);
 
        /* Wait for update_pending to go high. */
-       while (!(RREG32(EVERGREEN_GRPH_UPDATE + radeon_crtc->crtc_offset) & EVERGREEN_GRPH_SURFACE_UPDATE_PENDING));
+       for (i = 0; i < rdev->usec_timeout; i++) {
+               if (RREG32(EVERGREEN_GRPH_UPDATE + radeon_crtc->crtc_offset) & EVERGREEN_GRPH_SURFACE_UPDATE_PENDING)
+                       break;
+               udelay(1);
+       }
        DRM_DEBUG("Update pending now high. Unlocking vupdate_lock.\n");
 
        /* Unlock the lock, so double-buffering can take place inside vblank */

diff --git a/drivers/gpu/drm/radeon/r100.c b/drivers/gpu/drm/radeon/r100.c
index ad158ea..bfc08f6 100644 (file)
--- a/drivers/gpu/drm/radeon/r100.c
+++ b/drivers/gpu/drm/radeon/r100.c
@@ -187,13 +187,18 @@ u32 r100_page_flip(struct radeon_device *rdev, int crtc_id, u64 crtc_base)
 {
        struct radeon_crtc *radeon_crtc = rdev->mode_info.crtcs[crtc_id];
        u32 tmp = ((u32)crtc_base) | RADEON_CRTC_OFFSET__OFFSET_LOCK;
+       int i;
 
        /* Lock the graphics update lock */
        /* update the scanout addresses */
        WREG32(RADEON_CRTC_OFFSET + radeon_crtc->crtc_offset, tmp);
 
        /* Wait for update_pending to go high. */
-       while (!(RREG32(RADEON_CRTC_OFFSET + radeon_crtc->crtc_offset) & RADEON_CRTC_OFFSET__GUI_TRIG_OFFSET));
+       for (i = 0; i < rdev->usec_timeout; i++) {
+               if (RREG32(RADEON_CRTC_OFFSET + radeon_crtc->crtc_offset) & RADEON_CRTC_OFFSET__GUI_TRIG_OFFSET)
+                       break;
+               udelay(1);
+       }
        DRM_DEBUG("Update pending now high. Unlocking vupdate_lock.\n");
 
        /* Unlock the lock, so double-buffering can take place inside vblank */

diff --git a/drivers/gpu/drm/radeon/rs600.c b/drivers/gpu/drm/radeon/rs600.c
index 481b99e..b1053d6 100644 (file)
--- a/drivers/gpu/drm/radeon/rs600.c
+++ b/drivers/gpu/drm/radeon/rs600.c
@@ -62,6 +62,7 @@ u32 rs600_page_flip(struct radeon_device *rdev, int crtc_id, u64 crtc_base)
 {
        struct radeon_crtc *radeon_crtc = rdev->mode_info.crtcs[crtc_id];
        u32 tmp = RREG32(AVIVO_D1GRPH_UPDATE + radeon_crtc->crtc_offset);
+       int i;
 
        /* Lock the graphics update lock */
        tmp |= AVIVO_D1GRPH_UPDATE_LOCK;
@@ -74,7 +75,11 @@ u32 rs600_page_flip(struct radeon_device *rdev, int crtc_id, u64 crtc_base)
               (u32)crtc_base);
 
        /* Wait for update_pending to go high. */
-       while (!(RREG32(AVIVO_D1GRPH_UPDATE + radeon_crtc->crtc_offset) & AVIVO_D1GRPH_SURFACE_UPDATE_PENDING));
+       for (i = 0; i < rdev->usec_timeout; i++) {
+               if (RREG32(AVIVO_D1GRPH_UPDATE + radeon_crtc->crtc_offset) & AVIVO_D1GRPH_SURFACE_UPDATE_PENDING)
+                       break;
+               udelay(1);
+       }
        DRM_DEBUG("Update pending now high. Unlocking vupdate_lock.\n");
 
        /* Unlock the lock, so double-buffering can take place inside vblank */

diff --git a/drivers/gpu/drm/radeon/rv770.c b/drivers/gpu/drm/radeon/rv770.c
index a983f41..23ae1c6 100644 (file)
--- a/drivers/gpu/drm/radeon/rv770.c
+++ b/drivers/gpu/drm/radeon/rv770.c
@@ -47,6 +47,7 @@ u32 rv770_page_flip(struct radeon_device *rdev, int crtc_id, u64 crtc_base)
 {
        struct radeon_crtc *radeon_crtc = rdev->mode_info.crtcs[crtc_id];
        u32 tmp = RREG32(AVIVO_D1GRPH_UPDATE + radeon_crtc->crtc_offset);
+       int i;
 
        /* Lock the graphics update lock */
        tmp |= AVIVO_D1GRPH_UPDATE_LOCK;
@@ -66,7 +67,11 @@ u32 rv770_page_flip(struct radeon_device *rdev, int crtc_id, u64 crtc_base)
               (u32)crtc_base);
 
        /* Wait for update_pending to go high. */
-       while (!(RREG32(AVIVO_D1GRPH_UPDATE + radeon_crtc->crtc_offset) & AVIVO_D1GRPH_SURFACE_UPDATE_PENDING));
+       for (i = 0; i < rdev->usec_timeout; i++) {
+               if (RREG32(AVIVO_D1GRPH_UPDATE + radeon_crtc->crtc_offset) & AVIVO_D1GRPH_SURFACE_UPDATE_PENDING)
+                       break;
+               udelay(1);
+       }
        DRM_DEBUG("Update pending now high. Unlocking vupdate_lock.\n");
 
        /* Unlock the lock, so double-buffering can take place inside vblank */