Mesa (main): pan/mdg: Add 16 bytes of padding to the end of shaders

[GitLab Mirror]

Module: Mesa
Branch: main
Commit: 08495a948e16ac4fe54e282b77e8265551606219
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=08495a948e16ac4fe54e282b77e8265551606219

Author: Icecream95 <ixn at disroot.org>
Date:   Wed Jun 23 20:31:37 2021 +1200

pan/mdg: Add 16 bytes of padding to the end of shaders

Fixes INSTR_INVALID_PC faults when a shader ends on a 16MB boundary.

Cc: mesa-stable
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11551>

---

 src/panfrost/midgard/midgard_compile.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/panfrost/midgard/midgard_compile.c b/src/panfrost/midgard/midgard_compile.c
index 041e9586953..a8d254802fa 100644
--- a/src/panfrost/midgard/midgard_compile.c
+++ b/src/panfrost/midgard/midgard_compile.c
@@ -3238,6 +3238,12 @@ midgard_compile_shader_nir(nir_shader *nir,
                 fflush(stdout);
         }
 
+        /* A shader ending on a 16MB boundary causes INSTR_INVALID_PC faults,
+         * workaround by adding some padding to the end of the shader. (The
+         * kernel makes sure shader BOs can't cross 16MB boundaries.) */
+        if (binary->size)
+                memset(util_dynarray_grow(binary, uint8_t, 16), 0, 16);
+
         if ((midgard_debug & MIDGARD_DBG_SHADERDB || inputs->shaderdb) &&
             !nir->info.internal) {
                 unsigned nr_bundles = 0, nr_ins = 0;