[ 29/49] drm/radeon: update line buffer allocation for dce6

Greg Kroah-Hartman
2013-09-29T19:54:26Z

From: Alex Deucher <alexander.deucher@amd.com>

commit 290d24576ccf1aa0373d2185cedfe262d0d4952a upstream.

We need to allocate line buffer to each display when
setting up the watermarks. Failure to do so can lead
to a blank screen. This fixes blank screen problems
on dce6 asics.

Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=64850

Based on an initial fix from:
Jay Cornwall <jay.cornwall@amd.com>

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpu/drm/radeon/si.c | 23 +++++++++++++++++++----
drivers/gpu/drm/radeon/sid.h | 4 ++++
2 files changed, 23 insertions(+), 4 deletions(-)

--- a/drivers/gpu/drm/radeon/si.c
+++ b/drivers/gpu/drm/radeon/si.c
@@ -1467,7 +1467,8 @@ static u32 dce6_line_buffer_adjust(struc
struct drm_display_mode *mode,
struct drm_display_mode *other_mode)
{
- u32 tmp;
+ u32 tmp, buffer_alloc, i;
+ u32 pipe_offset = radeon_crtc->crtc_id * 0x20;
/*
* Line Buffer Setup
* There are 3 line buffers, each one shared by 2 display controllers.
@@ -1482,16 +1483,30 @@ static u32 dce6_line_buffer_adjust(struc
* non-linked crtcs for maximum line buffer allocation.
*/
if (radeon_crtc->base.enabled && mode) {
- if (other_mode)
+ if (other_mode) {
tmp = 0; /* 1/2 */
- else
+ buffer_alloc = 1;
+ } else {
tmp = 2; /* whole */
- } else
+ buffer_alloc = 2;
+ }
+ } else {
tmp = 0;
+ buffer_alloc = 0;
+ }

WREG32(DC_LB_MEMORY_SPLIT + radeon_crtc->crtc_offset,
DC_LB_MEMORY_CONFIG(tmp));

+ WREG32(PIPE0_DMIF_BUFFER_CONTROL + pipe_offset,
+ DMIF_BUFFERS_ALLOCATED(buffer_alloc));
+ for (i = 0; i < rdev->usec_timeout; i++) {
+ if (RREG32(PIPE0_DMIF_BUFFER_CONTROL + pipe_offset) &
+ DMIF_BUFFERS_ALLOCATED_COMPLETED)
+ break;
+ udelay(1);
+ }
+
if (radeon_crtc->base.enabled && mode) {
switch (tmp) {
case 0:
--- a/drivers/gpu/drm/radeon/sid.h
+++ b/drivers/gpu/drm/radeon/sid.h
@@ -97,6 +97,10 @@

#define DMIF_ADDR_CALC 0xC00

+#define PIPE0_DMIF_BUFFER_CONTROL 0x0ca0
+# define DMIF_BUFFERS_ALLOCATED(x) ((x) << 0)
+# define DMIF_BUFFERS_ALLOCATED_COMPLETED (1 << 4)
+
#define SRBM_STATUS 0xE50
#define GRBM_RQ_PENDING (1 << 5)
#define VMC_BUSY (1 << 8)