drm/radeon: Don't read from CP ring write pointer registers.

Apparently this doesn't always work reliably, e.g. at resume time.

Just initialize to 0, so the ring is considered empty.

Tested with hibernation on Sumo and Cayman cards.

Should fix https://bugs.launchpad.net/ubuntu/+source/linux/+bug/820746/ .

Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
cc: stable@kernel.org
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 dc0a5b56c81a6ee8dbc5d670a38c6330b683521a..f10d1c1c2554863c90189afe5c5b4f4557a354b9 100644 (file)
--- a/drivers/gpu/drm/radeon/evergreen.c
+++ b/drivers/gpu/drm/radeon/evergreen.c
@@ -1404,7 +1404,8 @@ int evergreen_cp_resume(struct radeon_device *rdev)
        /* Initialize the ring buffer's read and write pointers */
        WREG32(CP_RB_CNTL, tmp | RB_RPTR_WR_ENA);
        WREG32(CP_RB_RPTR_WR, 0);
-       WREG32(CP_RB_WPTR, 0);
+       rdev->cp.wptr = 0;
+       WREG32(CP_RB_WPTR, rdev->cp.wptr);
 
        /* set the wb address wether it's enabled or not */
        WREG32(CP_RB_RPTR_ADDR,
@@ -1426,7 +1427,6 @@ int evergreen_cp_resume(struct radeon_device *rdev)
        WREG32(CP_DEBUG, (1 << 27) | (1 << 28));
 
        rdev->cp.rptr = RREG32(CP_RB_RPTR);
-       rdev->cp.wptr = RREG32(CP_RB_WPTR);
 
        evergreen_cp_start(rdev);
        rdev->cp.ready = true;

diff --git a/drivers/gpu/drm/radeon/ni.c b/drivers/gpu/drm/radeon/ni.c
index cbf57d75d925be3c65f88738902091dc1cc8e7d0..99fbd793c08ce2bf95ccd8352794fd9c951a628a 100644 (file)
--- a/drivers/gpu/drm/radeon/ni.c
+++ b/drivers/gpu/drm/radeon/ni.c
@@ -1187,7 +1187,8 @@ int cayman_cp_resume(struct radeon_device *rdev)
 
        /* Initialize the ring buffer's read and write pointers */
        WREG32(CP_RB0_CNTL, tmp | RB_RPTR_WR_ENA);
-       WREG32(CP_RB0_WPTR, 0);
+       rdev->cp.wptr = 0;
+       WREG32(CP_RB0_WPTR, rdev->cp.wptr);
 
        /* set the wb address wether it's enabled or not */
        WREG32(CP_RB0_RPTR_ADDR, (rdev->wb.gpu_addr + RADEON_WB_CP_RPTR_OFFSET) & 0xFFFFFFFC);
@@ -1207,7 +1208,6 @@ int cayman_cp_resume(struct radeon_device *rdev)
        WREG32(CP_RB0_BASE, rdev->cp.gpu_addr >> 8);
 
        rdev->cp.rptr = RREG32(CP_RB0_RPTR);
-       rdev->cp.wptr = RREG32(CP_RB0_WPTR);
 
        /* ring1  - compute only */
        /* Set ring buffer size */
@@ -1220,7 +1220,8 @@ int cayman_cp_resume(struct radeon_device *rdev)
 
        /* Initialize the ring buffer's read and write pointers */
        WREG32(CP_RB1_CNTL, tmp | RB_RPTR_WR_ENA);
-       WREG32(CP_RB1_WPTR, 0);
+       rdev->cp1.wptr = 0;
+       WREG32(CP_RB1_WPTR, rdev->cp1.wptr);
 
        /* set the wb address wether it's enabled or not */
        WREG32(CP_RB1_RPTR_ADDR, (rdev->wb.gpu_addr + RADEON_WB_CP1_RPTR_OFFSET) & 0xFFFFFFFC);
@@ -1232,7 +1233,6 @@ int cayman_cp_resume(struct radeon_device *rdev)
        WREG32(CP_RB1_BASE, rdev->cp1.gpu_addr >> 8);
 
        rdev->cp1.rptr = RREG32(CP_RB1_RPTR);
-       rdev->cp1.wptr = RREG32(CP_RB1_WPTR);
 
        /* ring2 - compute only */
        /* Set ring buffer size */
@@ -1245,7 +1245,8 @@ int cayman_cp_resume(struct radeon_device *rdev)
 
        /* Initialize the ring buffer's read and write pointers */
        WREG32(CP_RB2_CNTL, tmp | RB_RPTR_WR_ENA);
-       WREG32(CP_RB2_WPTR, 0);
+       rdev->cp2.wptr = 0;
+       WREG32(CP_RB2_WPTR, rdev->cp2.wptr);
 
        /* set the wb address wether it's enabled or not */
        WREG32(CP_RB2_RPTR_ADDR, (rdev->wb.gpu_addr + RADEON_WB_CP2_RPTR_OFFSET) & 0xFFFFFFFC);
@@ -1257,7 +1258,6 @@ int cayman_cp_resume(struct radeon_device *rdev)
        WREG32(CP_RB2_BASE, rdev->cp2.gpu_addr >> 8);
 
        rdev->cp2.rptr = RREG32(CP_RB2_RPTR);
-       rdev->cp2.wptr = RREG32(CP_RB2_WPTR);
 
        /* start the rings */
        cayman_cp_start(rdev);

diff --git a/drivers/gpu/drm/radeon/r100.c b/drivers/gpu/drm/radeon/r100.c
index f2204cb1ccdfa96e0daa22ed9963a59555664f19..11e44a3479e309786aec916c47633973bac6d01b 100644 (file)
--- a/drivers/gpu/drm/radeon/r100.c
+++ b/drivers/gpu/drm/radeon/r100.c
@@ -990,7 +990,8 @@ int r100_cp_init(struct radeon_device *rdev, unsigned ring_size)
        /* Force read & write ptr to 0 */
        WREG32(RADEON_CP_RB_CNTL, tmp | RADEON_RB_RPTR_WR_ENA | RADEON_RB_NO_UPDATE);
        WREG32(RADEON_CP_RB_RPTR_WR, 0);
-       WREG32(RADEON_CP_RB_WPTR, 0);
+       rdev->cp.wptr = 0;
+       WREG32(RADEON_CP_RB_WPTR, rdev->cp.wptr);
 
        /* set the wb address whether it's enabled or not */
        WREG32(R_00070C_CP_RB_RPTR_ADDR,
@@ -1007,9 +1008,6 @@ int r100_cp_init(struct radeon_device *rdev, unsigned ring_size)
        WREG32(RADEON_CP_RB_CNTL, tmp);
        udelay(10);
        rdev->cp.rptr = RREG32(RADEON_CP_RB_RPTR);
-       rdev->cp.wptr = RREG32(RADEON_CP_RB_WPTR);
-       /* protect against crazy HW on resume */
-       rdev->cp.wptr &= rdev->cp.ptr_mask;
        /* Set cp mode to bus mastering & enable cp*/
        WREG32(RADEON_CP_CSQ_MODE,
               REG_SET(RADEON_INDIRECT2_START, indirect2_start) |

diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index aa5571b73aa02e947ec590ad6febb624778fc3da..c68427612e3bccce5e4434814e2de2a4dd9a2eb5 100644 (file)
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -2209,7 +2209,8 @@ int r600_cp_resume(struct radeon_device *rdev)
        /* Initialize the ring buffer's read and write pointers */
        WREG32(CP_RB_CNTL, tmp | RB_RPTR_WR_ENA);
        WREG32(CP_RB_RPTR_WR, 0);
-       WREG32(CP_RB_WPTR, 0);
+       rdev->cp.wptr = 0;
+       WREG32(CP_RB_WPTR, rdev->cp.wptr);
 
        /* set the wb address whether it's enabled or not */
        WREG32(CP_RB_RPTR_ADDR,
@@ -2231,7 +2232,6 @@ int r600_cp_resume(struct radeon_device *rdev)
        WREG32(CP_DEBUG, (1 << 27) | (1 << 28));
 
        rdev->cp.rptr = RREG32(CP_RB_RPTR);
-       rdev->cp.wptr = RREG32(CP_RB_WPTR);
 
        r600_cp_start(rdev);
        rdev->cp.ready = true;