intel: fix URB programming for GT1s

We're missing a programming restriction.

Hopefully fixing
dEQP-VK.spirv_assembly.instruction.graphics.float16.arithmetic_1.* on
Gfx9atoms

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: mesa-stable
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/6216
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>.
Tested-by: Mark Janes <markjanes@swizzler.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15596>

diff --git a/src/intel/common/intel_urb_config.c b/src/intel/common/intel_urb_config.c
index 52551d0..2f7d72c 100644 (file)
--- a/src/intel/common/intel_urb_config.c
+++ b/src/intel/common/intel_urb_config.c
@@ -225,14 +225,32 @@ intel_get_urb_config(const struct intel_device_info *devinfo,
    }
 
    /* Lay out the URB in pipeline order: push constants, VS, HS, DS, GS. */
-   int next = push_constant_chunks;
+   int first_urb = push_constant_chunks;
+
+   /* From the BDW PRM: for 3DSTATE_URB_*: VS URB Starting Address
+    *
+    *    "Value: [4,48] Device [SliceCount] GT 1"
+    *
+    * From the ICL PRMs and above :
+    *
+    *    "If CTXT_SR_CTL::POSH_Enable is clear and Push Constants are required
+    *     or Device[SliceCount] GT 1, the lower limit is 4."
+    *
+    *    "If Push Constants are not required andDevice[SliceCount] == 1, the
+    *     lower limit is 0."
+    */
+   if ((devinfo->ver == 8 && devinfo->num_slices == 1) ||
+       (devinfo->ver >= 11 && push_constant_chunks > 0 && devinfo->num_slices == 1))
+      first_urb = MAX2(first_urb, 4);
+
+   int next_urb = first_urb;
    for (int i = MESA_SHADER_VERTEX; i <= MESA_SHADER_GEOMETRY; i++) {
       if (entries[i]) {
-         start[i] = next;
-         next += chunks[i];
+         start[i] = next_urb;
+         next_urb += chunks[i];
       } else {
-         /* Just put disabled stages at the beginning. */
-         start[i] = 0;
+         /* Put disabled stages at the beginning of the valid range */
+         start[i] = first_urb;
       }
    }
 
@@ -359,4 +377,3 @@ intel_get_mesh_urb_config(const struct intel_device_info *devinfo,
 
    return r;
 }
-