drm/radeon: fix backend map setup on 1 RB trinity boards

Need to adjust the backend map depending on which RB is
enabled.  This is the trinity equivalent of:
f7eb97300832f4fe5fe916c5d84cd2e25169330e

May fix:
https://bugs.freedesktop.org/show_bug.cgi?id=57919

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

1 files changed, 16 insertions, 5 deletions

diff --git a/drivers/gpu/drm/radeon/ni.c b/drivers/gpu/drm/radeon/ni.c
index e77c9273bc9c..a7d3de73be04 100644
--- a/drivers/gpu/drm/radeon/ni.c
+++ b/drivers/gpu/drm/radeon/ni.c
@@ -616,11 +616,22 @@ static void cayman_gpu_init(struct radeon_device *rdev)
         WREG32(DMA_TILING_CONFIG + DMA0_REGISTER_OFFSET, gb_addr_config);
         WREG32(DMA_TILING_CONFIG + DMA1_REGISTER_OFFSET, gb_addr_config);
 
-        tmp = gb_addr_config & NUM_PIPES_MASK;
-        tmp = r6xx_remap_render_backend(rdev, tmp,
-                                        rdev->config.cayman.max_backends_per_se *
-                                        rdev->config.cayman.max_shader_engines,
-                                        CAYMAN_MAX_BACKENDS, disabled_rb_mask);
+        if ((rdev->config.cayman.max_backends_per_se == 1) &&
+            (rdev->flags & RADEON_IS_IGP)) {
+                if ((disabled_rb_mask & 3) == 1) {
+                        /* RB0 disabled, RB1 enabled */
+                        tmp = 0x11111111;
+                } else {
+                        /* RB1 disabled, RB0 enabled */
+                        tmp = 0x00000000;
+                }
+        } else {
+                tmp = gb_addr_config & NUM_PIPES_MASK;
+                tmp = r6xx_remap_render_backend(rdev, tmp,
+                                                rdev->config.cayman.max_backends_per_se *
+                                                rdev->config.cayman.max_shader_engines,
+                                                CAYMAN_MAX_BACKENDS, disabled_rb_mask);
+        }
         WREG32(GB_BACKEND_MAP, tmp);
 
         cgts_tcc_disable = 0xffff0000;