9 files changed, 42 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/r100.c b/drivers/gpu/drm/radeon/r100.c
index 5aa29952731..5d14732dc28 100644
--- a/drivers/gpu/drm/radeon/r100.c
+++ b/drivers/gpu/drm/radeon/r100.c
@@ -3809,6 +3809,31 @@ void r100_fini(struct radeon_device *rdev)
         rdev->bios = NULL;
 }
 
+/*
+ * Due to how kexec works, it can leave the hw fully initialised when it
+ * boots the new kernel. However doing our init sequence with the CP and
+ * WB stuff setup causes GPU hangs on the RN50 at least. So at startup
+ * do some quick sanity checks and restore sane values to avoid this
+ * problem.
+ */
+void r100_restore_sanity(struct radeon_device *rdev)
+{
+        u32 tmp;
+
+        tmp = RREG32(RADEON_CP_CSQ_CNTL);
+        if (tmp) {
+                WREG32(RADEON_CP_CSQ_CNTL, 0);
+        }
+        tmp = RREG32(RADEON_CP_RB_CNTL);
+        if (tmp) {
+                WREG32(RADEON_CP_RB_CNTL, 0);
+        }
+        tmp = RREG32(RADEON_SCRATCH_UMSK);
+        if (tmp) {
+                WREG32(RADEON_SCRATCH_UMSK, 0);
+        }
+}
+
 int r100_init(struct radeon_device *rdev)
 {
         int r;
@@ -3821,6 +3846,8 @@ int r100_init(struct radeon_device *rdev)
         radeon_scratch_init(rdev);
         /* Initialize surface registers */
         radeon_surface_init(rdev);
+        /* sanity check some register to avoid hangs like after kexec */
+        r100_restore_sanity(rdev);
         /* TODO: disable VGA need to use VGA request */
         /* BIOS*/
         if (!radeon_get_bios(rdev)) {
diff --git a/drivers/gpu/drm/radeon/r300.c b/drivers/gpu/drm/radeon/r300.c
index 7e81db5eb80..3c34da0c899 100644
--- a/drivers/gpu/drm/radeon/r300.c
+++ b/drivers/gpu/drm/radeon/r300.c
@@ -1377,6 +1377,8 @@ int r300_init(struct radeon_device *rdev)
         /* Initialize surface registers */
         radeon_surface_init(rdev);
         /* TODO: disable VGA need to use VGA request */
+        /* restore some register to sane defaults */
+        r100_restore_sanity(rdev);
         /* BIOS*/
         if (!radeon_get_bios(rdev)) {
                 if (ASIC_IS_AVIVO(rdev))
diff --git a/drivers/gpu/drm/radeon/r420.c b/drivers/gpu/drm/radeon/r420.c
index e6c89142bb4..59f7bccc5be 100644
--- a/drivers/gpu/drm/radeon/r420.c
+++ b/drivers/gpu/drm/radeon/r420.c
@@ -343,6 +343,8 @@ int r420_init(struct radeon_device *rdev)
         /* Initialize surface registers */
         radeon_surface_init(rdev);
         /* TODO: disable VGA need to use VGA request */
+        /* restore some register to sane defaults */
+        r100_restore_sanity(rdev);
         /* BIOS*/
         if (!radeon_get_bios(rdev)) {
                 if (ASIC_IS_AVIVO(rdev))
diff --git a/drivers/gpu/drm/radeon/r520.c b/drivers/gpu/drm/radeon/r520.c
index 34330df2848..213e2e0027a 100644
--- a/drivers/gpu/drm/radeon/r520.c
+++ b/drivers/gpu/drm/radeon/r520.c
@@ -230,6 +230,8 @@ int r520_init(struct radeon_device *rdev)
         radeon_scratch_init(rdev);
         /* Initialize surface registers */
         radeon_surface_init(rdev);
+        /* restore some register to sane defaults */
+        r100_restore_sanity(rdev);
         /* TODO: disable VGA need to use VGA request */
         /* BIOS*/
         if (!radeon_get_bios(rdev)) {
diff --git a/drivers/gpu/drm/radeon/radeon_asic.h b/drivers/gpu/drm/radeon/radeon_asic.h
index c0bbaa64157..a5aff755f0d 100644
--- a/drivers/gpu/drm/radeon/radeon_asic.h
+++ b/drivers/gpu/drm/radeon/radeon_asic.h
@@ -113,6 +113,7 @@ void r100_wb_fini(struct radeon_device *rdev);
 int r100_wb_init(struct radeon_device *rdev);
 int r100_cp_reset(struct radeon_device *rdev);
 void r100_vga_render_disable(struct radeon_device *rdev);
+void r100_restore_sanity(struct radeon_device *rdev);
 int r100_cs_track_check_pkt3_indx_buffer(struct radeon_cs_parser *p,
                                          struct radeon_cs_packet *pkt,
                                          struct radeon_bo *robj);
diff --git a/drivers/gpu/drm/radeon/rs400.c b/drivers/gpu/drm/radeon/rs400.c
index 9e4240b3bf0..c178481101e 100644
--- a/drivers/gpu/drm/radeon/rs400.c
+++ b/drivers/gpu/drm/radeon/rs400.c
@@ -480,6 +480,8 @@ int rs400_init(struct radeon_device *rdev)
         /* Initialize surface registers */
         radeon_surface_init(rdev);
         /* TODO: disable VGA need to use VGA request */
+        /* restore some register to sane defaults */
+        r100_restore_sanity(rdev);
         /* BIOS*/
         if (!radeon_get_bios(rdev)) {
                 if (ASIC_IS_AVIVO(rdev))
diff --git a/drivers/gpu/drm/radeon/rs600.c b/drivers/gpu/drm/radeon/rs600.c
index 27d2e706c65..c5760921d16 100644
--- a/drivers/gpu/drm/radeon/rs600.c
+++ b/drivers/gpu/drm/radeon/rs600.c
@@ -879,6 +879,8 @@ int rs600_init(struct radeon_device *rdev)
         radeon_scratch_init(rdev);
         /* Initialize surface registers */
         radeon_surface_init(rdev);
+        /* restore some register to sane defaults */
+        r100_restore_sanity(rdev);
         /* BIOS */
         if (!radeon_get_bios(rdev)) {
                 if (ASIC_IS_AVIVO(rdev))
diff --git a/drivers/gpu/drm/radeon/rs690.c b/drivers/gpu/drm/radeon/rs690.c
index 23676b659e6..3dde54d57d0 100644
--- a/drivers/gpu/drm/radeon/rs690.c
+++ b/drivers/gpu/drm/radeon/rs690.c
@@ -707,6 +707,8 @@ int rs690_init(struct radeon_device *rdev)
         radeon_scratch_init(rdev);
         /* Initialize surface registers */
         radeon_surface_init(rdev);
+        /* restore some register to sane defaults */
+        r100_restore_sanity(rdev);
         /* TODO: disable VGA need to use VGA request */
         /* BIOS*/
         if (!radeon_get_bios(rdev)) {
diff --git a/drivers/gpu/drm/radeon/rv515.c b/drivers/gpu/drm/radeon/rv515.c
index 7d9a7b0a180..3f04f735dea 100644
--- a/drivers/gpu/drm/radeon/rv515.c
+++ b/drivers/gpu/drm/radeon/rv515.c
@@ -468,6 +468,8 @@ int rv515_init(struct radeon_device *rdev)
         /* Initialize surface registers */
         radeon_surface_init(rdev);
         /* TODO: disable VGA need to use VGA request */
+        /* restore some register to sane defaults */
+        r100_restore_sanity(rdev);
         /* BIOS*/
         if (!radeon_get_bios(rdev)) {
                 if (ASIC_IS_AVIVO(rdev))