anv: Add proper support for depth clamping

Signed-off-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Cc: "12.0" <mesa-stable@lists.freedesktop.org>

src/intel/vulkan/anv_device.c

@@ -380,7 +380,7 @@ void anv_GetPhysicalDeviceFeatures(
       .logicOp                                  = true,
       .multiDrawIndirect                        = false,
       .drawIndirectFirstInstance                = false,
-      .depthClamp                               = false,
+      .depthClamp                               = true,
       .depthBiasClamp                           = false,
       .fillModeNonSolid                         = true,
       .depthBounds                              = false,

src/intel/vulkan/anv_meta_clear.c

@@ -173,6 +173,7 @@ create_pipeline(struct anv_device *device,
             .cullMode = VK_CULL_MODE_NONE,
             .frontFace = VK_FRONT_FACE_COUNTER_CLOCKWISE,
             .depthBiasEnable = false,
+            .depthClampEnable = true,
          },
          .pMultisampleState = &(VkPipelineMultisampleStateCreateInfo) {
             .sType = VK_STRUCTURE_TYPE_PIPELINE_MULTISAMPLE_STATE_CREATE_INFO,

src/intel/vulkan/anv_pipeline.c

@@ -1165,6 +1165,8 @@ anv_pipeline_init(struct anv_pipeline *pipeline,
    pipeline->batch.relocs = &pipeline->batch_relocs;
 
    copy_non_dynamic_state(pipeline, pCreateInfo);
+   pipeline->depth_clamp_enable = pCreateInfo->pRasterizationState &&
+                                  pCreateInfo->pRasterizationState->depthClampEnable;
 
    pipeline->use_repclear = extra && extra->use_repclear;
 

src/intel/vulkan/anv_private.h

@@ -1360,7 +1360,8 @@ VkResult
 anv_cmd_buffer_new_binding_table_block(struct anv_cmd_buffer *cmd_buffer);
 
 void gen8_cmd_buffer_emit_viewport(struct anv_cmd_buffer *cmd_buffer);
-void gen8_cmd_buffer_emit_depth_viewport(struct anv_cmd_buffer *cmd_buffer);
+void gen8_cmd_buffer_emit_depth_viewport(struct anv_cmd_buffer *cmd_buffer,
+                                         bool depth_clamp_enable);
 void gen7_cmd_buffer_emit_scissor(struct anv_cmd_buffer *cmd_buffer);
 
 void anv_cmd_buffer_emit_state_base_address(struct anv_cmd_buffer *cmd_buffer);
@@ -1485,6 +1486,8 @@ struct anv_pipeline {
 
    uint32_t                                     cs_right_mask;
 
+   bool                                         depth_clamp_enable;
+
    struct {
       uint32_t                                  sf[7];
       uint32_t                                  depth_stencil_state[3];

src/intel/vulkan/gen7_pipeline.c

@@ -196,6 +196,7 @@ genX(graphics_pipeline_create)(
       clip.ClipEnable               = !(extra && extra->use_rectlist),
       clip.APIMode                  = APIMODE_OGL,
       clip.ViewportXYClipTestEnable = true,
+      clip.ViewportZClipTestEnable  = !pipeline->depth_clamp_enable,
       clip.ClipMode                 = CLIPMODE_NORMAL,
 
       clip.TriangleStripListProvokingVertexSelect   = 0,

src/intel/vulkan/gen8_cmd_buffer.c

@@ -77,7 +77,8 @@ gen8_cmd_buffer_emit_viewport(struct anv_cmd_buffer *cmd_buffer)
 }
 
 void
-gen8_cmd_buffer_emit_depth_viewport(struct anv_cmd_buffer *cmd_buffer)
+gen8_cmd_buffer_emit_depth_viewport(struct anv_cmd_buffer *cmd_buffer,
+                                    bool depth_clamp_enable)
 {
    uint32_t count = cmd_buffer->state.dynamic.viewport.count;
    const VkViewport *viewports = cmd_buffer->state.dynamic.viewport.viewports;
@@ -88,8 +89,8 @@ gen8_cmd_buffer_emit_depth_viewport(struct anv_cmd_buffer *cmd_buffer)
       const VkViewport *vp = &viewports[i];
 
       struct GENX(CC_VIEWPORT) cc_viewport = {
-         .MinimumDepth = vp->minDepth,
-         .MaximumDepth = vp->maxDepth,
+         .MinimumDepth = depth_clamp_enable ? vp->minDepth : 0.0f,
+         .MaximumDepth = depth_clamp_enable ? vp->maxDepth : 1.0f,
       };
 
       GENX(CC_VIEWPORT_pack)(NULL, cc_state.map + i * 8, &cc_viewport);

src/intel/vulkan/gen8_pipeline.c

@@ -85,11 +85,11 @@ emit_rs_state(struct anv_pipeline *pipeline,
       .BackFaceFillMode = vk_to_gen_fillmode[info->polygonMode],
       .ScissorRectangleEnable = !(extra && extra->use_rectlist),
 #if GEN_GEN == 8
-      .ViewportZClipTestEnable = true,
+      .ViewportZClipTestEnable = !pipeline->depth_clamp_enable,
 #else
       /* GEN9+ splits ViewportZClipTestEnable into near and far enable bits */
-      .ViewportZFarClipTestEnable = true,
-      .ViewportZNearClipTestEnable = true,
+      .ViewportZFarClipTestEnable = !pipeline->depth_clamp_enable,
+      .ViewportZNearClipTestEnable = !pipeline->depth_clamp_enable,
 #endif
       .GlobalDepthOffsetEnableSolid = info->depthBiasEnable,
       .GlobalDepthOffsetEnableWireframe = info->depthBiasEnable,

src/intel/vulkan/genX_cmd_buffer.c

@@ -525,9 +525,13 @@ genX(cmd_buffer_flush_state)(struct anv_cmd_buffer *cmd_buffer)
    if (dirty)
       gen7_cmd_buffer_emit_descriptor_pointers(cmd_buffer, dirty);
 
-   if (cmd_buffer->state.dirty & ANV_CMD_DIRTY_DYNAMIC_VIEWPORT) {
+   if (cmd_buffer->state.dirty & ANV_CMD_DIRTY_DYNAMIC_VIEWPORT)
       gen8_cmd_buffer_emit_viewport(cmd_buffer);
-      gen8_cmd_buffer_emit_depth_viewport(cmd_buffer);
+
+   if (cmd_buffer->state.dirty & (ANV_CMD_DIRTY_DYNAMIC_VIEWPORT |
+                                  ANV_CMD_DIRTY_PIPELINE)) {
+      gen8_cmd_buffer_emit_depth_viewport(cmd_buffer,
+                                          pipeline->depth_clamp_enable);
    }
 
    if (cmd_buffer->state.dirty & ANV_CMD_DIRTY_DYNAMIC_SCISSOR)