[Mesa-dev] [PATCH v2] isl: add MCS width constraint 16 samples

[Lionel Landwerlin]

Applies on top of Jason's patch :

   https://patchwork.freedesktop.org/patch/139603/

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin at intel.com>
Cc: Jason Ekstrand <jason at jlekstrand.net>
---
 src/intel/isl/isl.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/intel/isl/isl.c b/src/intel/isl/isl.c
index 1a47da5257..b7f3aaee1c 100644
--- a/src/intel/isl/isl.c
+++ b/src/intel/isl/isl.c
@@ -1417,6 +1417,15 @@ isl_surf_get_mcs_surf(const struct isl_device *dev,
    assert(surf->levels == 1);
    assert(surf->logical_level0_px.depth == 1);

+   /* Internal documentation says (not found in PRMs) :
+    *
+    *    "If Number of Multisamples is MULTISAMPLECOUNT_16, then Width must be
+    *     8K texels or less, or the surface must not use the a multisample
+    *     control surface (MCS)."
+    */
+   if (surf->samples == 16 && surf->width > 8192)
+      return false;
+
    enum isl_format mcs_format;
    switch (surf->samples) {
    case 2:  mcs_format = ISL_FORMAT_MCS_2X;  break;
--
2.11.0