[Intel-gfx] [PATCH 5/7 v2] drm/i915: Support fused off pipe C configurations

[Damien Lespiau]

Starting from IVB, pipe C can be fused off. We have yet to see such
configuration in the wild though (ie not tested).

v2: Actually tweak num_pipes, not num_planes.

Signed-off-by: Damien Lespiau <damien.lespiau at intel.com>
---
 drivers/gpu/drm/i915/i915_dma.c | 4 ++++
 drivers/gpu/drm/i915/i915_reg.h | 1 +
 2 files changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index 3e9828c..6d39f94 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1480,6 +1480,10 @@ static void intel_device_info_runtime_init(struct drm_device *dev)
 			DRM_DEBUG_DRIVER("Display fused off, disabling\n");
 			info->num_pipes = 0;
 		}
+		if (fuse_strap & IVB_PIPE_C_DISABLE) {
+			DRM_DEBUG_DRIVER("Pipe C fused off, disabling\n");
+			info->num_pipes = 2;
+		}
 	}
 }
 
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 5a0cd52..9e127b2 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -4118,6 +4118,7 @@
 #define  ILK_INTERNAL_GRAPHICS_DISABLE	(1 << 31)
 #define  ILK_INTERNAL_DISPLAY_DISABLE	(1 << 30)
 #define  ILK_DISPLAY_DEBUG_DISABLE	(1 << 29)
+#define  IVB_PIPE_C_DISABLE		(1 << 28)
 #define  ILK_HDCP_DISABLE		(1 << 25)
 #define  ILK_eDP_A_DISABLE		(1 << 24)
 #define  HSW_CDCLK_LIMIT		(1 << 24)
-- 
1.8.3.1