v3d: Emit the VCM_CACHE_SIZE packet.

This is needed to ensure that we don't get blocked waiting for VPM space
with bin/render overlapping.

Cc: "18.2" <[email protected]>
(cherry picked from commit 1561e4984eb03d6946d19b820b83a96bbbd83b98)

4 files changed, 36 insertions, 4 deletions

diff --git a/src/broadcom/cle/v3d_packet_v33.xml b/src/broadcom/cle/v3d_packet_v33.xml
index 6ce8299e26b..f471d542c56 100644
--- a/src/broadcom/cle/v3d_packet_v33.xml
+++ b/src/broadcom/cle/v3d_packet_v33.xml
@@ -528,6 +528,16 @@
     <field name="number of attribute arrays" size="5" start="0" type="uint"/>
   </packet>
 
+  <packet code="71" name="VCM Cache Size" min_ver="41">
+    <field name="Number of 16-vertex batches for rendering" size="4" start="4" type="uint"/>
+    <field name="Number of 16-vertex batches for binning" size="4" start="0" type="uint"/>
+  </packet>
+
+  <packet code="73" name="VCM Cache Size" max_ver="33">
+    <field name="Number of 16-vertex batches for rendering" size="4" start="4" type="uint"/>
+    <field name="Number of 16-vertex batches for binning" size="4" start="0" type="uint"/>
+  </packet>
+
   <packet code="73" name="Transform Feedback Buffer" min_ver="41">
     <field name="Buffer Address" size="32" start="32" type="address"/>
     <field name="Buffer Size in 32-bit words" size="30" start="2" type="uint"/>
diff --git a/src/broadcom/common/v3d_device_info.h b/src/broadcom/common/v3d_device_info.h
index 5685c7a2161..b0a2a02154c 100644
--- a/src/broadcom/common/v3d_device_info.h
+++ b/src/broadcom/common/v3d_device_info.h
@@ -27,13 +27,14 @@
 #include <stdint.h>
 
 /**
- * Struct for tracking features of the V3D chip. This is where we'll store
- * boolean flags for features in a specific version, but for now it's just the
- * version
+ * Struct for tracking features of the V3D chip across driver and compiler.
  */
 struct v3d_device_info {
         /** Simple V3D version: major * 10 + minor */
         uint8_t ver;
+
+        /** Size of the VPM, in bytes. */
+        int vpm_size;
 };
 
 #endif
diff --git a/src/broadcom/compiler/v3d_compiler.h b/src/broadcom/compiler/v3d_compiler.h
index 70edeed2730..070e6a3aa59 100644
--- a/src/broadcom/compiler/v3d_compiler.h
+++ b/src/broadcom/compiler/v3d_compiler.h
@@ -648,6 +648,9 @@ struct v3d_vs_prog_data {
 
         /* Total number of components written, for the shader state record. */
         uint32_t vpm_output_size;
+
+        /* Value to be programmed in VCM_CACHE_SIZE. */
+        uint8_t vcm_cache_size;
 };
 
 struct v3d_fs_prog_data {
diff --git a/src/broadcom/compiler/vir.c b/src/broadcom/compiler/vir.c
index fc0b34d4453..1c8223165c6 100644
--- a/src/broadcom/compiler/vir.c
+++ b/src/broadcom/compiler/vir.c
@@ -756,10 +756,28 @@ uint64_t *v3d_compile_vs(const struct v3d_compiler *compiler,
         if (prog_data->uses_iid)
                 prog_data->vpm_input_size++;
 
-        /* Input/output segment size are in 8x32-bit multiples. */
+        /* Input/output segment size are in sectors (8 rows of 32 bits per
+         * channel).
+         */
         prog_data->vpm_input_size = align(prog_data->vpm_input_size, 8) / 8;
         prog_data->vpm_output_size = align(c->num_vpm_writes, 8) / 8;
 
+        /* Compute VCM cache size.  We set up our program to take up less than
+         * half of the VPM, so that any set of bin and render programs won't
+         * run out of space.  We need space for at least one input segment,
+         * and then allocate the rest to output segments (one for the current
+         * program, the rest to VCM).  The valid range of the VCM cache size
+         * field is 1-4 16-vertex batches, but GFXH-1744 limits us to 2-4
+         * batches.
+         */
+        assert(c->devinfo->vpm_size);
+        int sector_size = 16 * sizeof(uint32_t) * 8;
+        int vpm_size_in_sectors = c->devinfo->vpm_size / sector_size;
+        int half_vpm = vpm_size_in_sectors / 2;
+        int vpm_output_batches = half_vpm - prog_data->vpm_input_size;
+        assert(vpm_output_batches >= 2);
+        prog_data->vcm_cache_size = CLAMP(vpm_output_batches - 1, 2, 4);
+
         return v3d_return_qpu_insts(c, final_assembly_size);
 }