From 946eacbafb47c8b94d47e7c9d2a8b02fff5a22fa Mon Sep 17 00:00:00 2001
From: Jonathan Marek <jonathan@marek.ca>
Date: Tue, 11 Feb 2020 21:08:58 -0500
Subject: [PATCH] freedreno/a6xx: document some unknown bits

Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3814>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3814>
---
 src/freedreno/registers/a6xx.xml                    | 10 +++++++++-
 src/freedreno/vulkan/tu_pipeline.c                  |  4 ++--
 src/gallium/drivers/freedreno/a6xx/fd6_rasterizer.c |  2 +-
 3 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/src/freedreno/registers/a6xx.xml b/src/freedreno/registers/a6xx.xml
index 2c4266e90b4..c03b3e6f133 100644
--- a/src/freedreno/registers/a6xx.xml
+++ b/src/freedreno/registers/a6xx.xml
@@ -1767,7 +1767,15 @@ to upconvert to 32b float internally?
 	<!-- always 0x03200000 ? -->
 	<reg32 offset="0x0e12" name="UCHE_UNKNOWN_0E12"/>
 
-	<reg32 offset="0x8000" name="GRAS_UNKNOWN_8000"/>
+	<reg32 offset="0x8000" name="GRAS_DISABLE_CNTL">
+		 <!-- likely something clip-disable related -->
+		<bitfield name="UNK0" pos="0" type="boolean"/>
+		<!-- guess based on a3xx and meaning of bits 8 and 9
+		     if the guess is right then this is related to point sprite clipping -->
+		<bitfield name="VP_CLIP_CODE_IGNORE" pos="7" type="boolean"/>
+		<bitfield name="VP_XFORM_DISABLE" pos="8" type="boolean"/>
+		<bitfield name="PERSP_DIVISION_DISABLE" pos="9" type="boolean"/>
+	</reg32>
 	<reg32 offset="0x8001" name="GRAS_UNKNOWN_8001"/>
 	<reg32 offset="0x8002" name="GRAS_UNKNOWN_8002"/>
 	<reg32 offset="0x8003" name="GRAS_UNKNOWN_8003"/>
diff --git a/src/freedreno/vulkan/tu_pipeline.c b/src/freedreno/vulkan/tu_pipeline.c
index a0e22e7bce8..5519cfe7139 100644
--- a/src/freedreno/vulkan/tu_pipeline.c
+++ b/src/freedreno/vulkan/tu_pipeline.c
@@ -1223,8 +1223,8 @@ tu6_emit_scissor(struct tu_cs *cs, const VkRect2D *scissor)
 static void
 tu6_emit_gras_unknowns(struct tu_cs *cs)
 {
-   tu_cs_emit_pkt4(cs, REG_A6XX_GRAS_UNKNOWN_8000, 1);
-   tu_cs_emit(cs, 0x80);
+   tu_cs_emit_pkt4(cs, REG_A6XX_GRAS_DISABLE_CNTL, 1);
+   tu_cs_emit(cs, A6XX_GRAS_DISABLE_CNTL_VP_CLIP_CODE_IGNORE);
    tu_cs_emit_pkt4(cs, REG_A6XX_GRAS_UNKNOWN_8001, 1);
    tu_cs_emit(cs, 0x0);
    tu_cs_emit_pkt4(cs, REG_A6XX_GRAS_LAYER_CNTL, 1);
diff --git a/src/gallium/drivers/freedreno/a6xx/fd6_rasterizer.c b/src/gallium/drivers/freedreno/a6xx/fd6_rasterizer.c
index 4cc31c5d38b..db0c249d83e 100644
--- a/src/gallium/drivers/freedreno/a6xx/fd6_rasterizer.c
+++ b/src/gallium/drivers/freedreno/a6xx/fd6_rasterizer.c
@@ -52,7 +52,7 @@ __fd6_setup_rasterizer_stateobj(struct fd_context *ctx,
 	}
 
 	OUT_REG(ring,
-		A6XX_GRAS_UNKNOWN_8000(.unknown = 0x80),
+		A6XX_GRAS_DISABLE_CNTL(.vp_clip_code_ignore = 1),
 		A6XX_GRAS_UNKNOWN_8001());
 
 	OUT_REG(ring,
-- 
2.30.2