drm/radeon: skip MC reset as it's probably not hung

The MC is mostly likely busy (e.g., display requests), not hung
so no need to reset it.  Doing an MC reset is tricky and not
particularly reliable.  Fixes hangs in certain cases.

Reported-by: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/radeon/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c
index 3c38ea46531cfe6b9bc6397c01337393fe3e8a51..305a657bf21561242991e56365439781df54c2df 100644 (file)
--- a/drivers/gpu/drm/radeon/evergreen.c
+++ b/drivers/gpu/drm/radeon/evergreen.c
@@ -2438,6 +2438,12 @@ static u32 evergreen_gpu_check_soft_reset(struct radeon_device *rdev)
        if (tmp & L2_BUSY)
                reset_mask |= RADEON_RESET_VMC;
 
+       /* Skip MC reset as it's mostly likely not hung, just busy */
+       if (reset_mask & RADEON_RESET_MC) {
+               DRM_DEBUG("MC busy: 0x%08X, clearing.\n", reset_mask);
+               reset_mask &= ~RADEON_RESET_MC;
+       }
+
        return reset_mask;
 }
 

diff --git a/drivers/gpu/drm/radeon/ni.c b/drivers/gpu/drm/radeon/ni.c
index 7cead763be9ec760ad05919ae11d4e5a6b504d85..d4c633e12863bb9c546d6eae81d3fb7f835303e9 100644 (file)
--- a/drivers/gpu/drm/radeon/ni.c
+++ b/drivers/gpu/drm/radeon/ni.c
@@ -1381,6 +1381,12 @@ static u32 cayman_gpu_check_soft_reset(struct radeon_device *rdev)
        if (tmp & L2_BUSY)
                reset_mask |= RADEON_RESET_VMC;
 
+       /* Skip MC reset as it's mostly likely not hung, just busy */
+       if (reset_mask & RADEON_RESET_MC) {
+               DRM_DEBUG("MC busy: 0x%08X, clearing.\n", reset_mask);
+               reset_mask &= ~RADEON_RESET_MC;
+       }
+
        return reset_mask;
 }
 

diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index 6d4b5611daf4b2f96c05c00593c186acbb015e7f..0740db3fcd2268af78e286ec6ec634570ff7efcd 100644 (file)
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -1394,6 +1394,12 @@ static u32 r600_gpu_check_soft_reset(struct radeon_device *rdev)
        if (r600_is_display_hung(rdev))
                reset_mask |= RADEON_RESET_DISPLAY;
 
+       /* Skip MC reset as it's mostly likely not hung, just busy */
+       if (reset_mask & RADEON_RESET_MC) {
+               DRM_DEBUG("MC busy: 0x%08X, clearing.\n", reset_mask);
+               reset_mask &= ~RADEON_RESET_MC;
+       }
+
        return reset_mask;
 }
 

diff --git a/drivers/gpu/drm/radeon/si.c b/drivers/gpu/drm/radeon/si.c
index 80979ed951eb1afdacafa23b89ac7e116075858f..9128120da04441621ec1050b8cb0ff236704b7cf 100644 (file)
--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -2284,6 +2284,12 @@ static u32 si_gpu_check_soft_reset(struct radeon_device *rdev)
        if (tmp & L2_BUSY)
                reset_mask |= RADEON_RESET_VMC;
 
+       /* Skip MC reset as it's mostly likely not hung, just busy */
+       if (reset_mask & RADEON_RESET_MC) {
+               DRM_DEBUG("MC busy: 0x%08X, clearing.\n", reset_mask);
+               reset_mask &= ~RADEON_RESET_MC;
+       }
+
        return reset_mask;
 }