pan/decode: Validate AFBC fields are zero when AFBC is disabled

There is no "chunknown" structure; that part of the union is an artefact
from falsely believing vertex/tiler MFBDs could have render targets
attached (they can't). These are just plain old AFBC fields, and if
there is no AFBC, it's error to set these field.

Signed-off-by: Alyssa Rosenzweig <[email protected]>

2 files changed, 20 insertions, 33 deletions

diff --git a/src/panfrost/include/panfrost-job.h b/src/panfrost/include/panfrost-job.h
index e08aac9c73a..ffcfd67bab6 100644
--- a/src/panfrost/include/panfrost-job.h
+++ b/src/panfrost/include/panfrost-job.h
@@ -1522,27 +1522,21 @@ struct bifrost_render_target {
 
         u64 zero1;
 
-        union {
-                struct {
-                        /* Stuff related to ARM Framebuffer Compression. When AFBC is enabled,
-                         * there is an extra metadata buffer that contains 16 bytes per tile.
-                         * The framebuffer needs to be the same size as before, since we don't
-                         * know ahead of time how much space it will take up. The
-                         * framebuffer_stride is set to 0, since the data isn't stored linearly
-                         * anymore.
-                         */
-
-                        mali_ptr metadata;
-                        u32 stride; // stride in units of tiles
-                        u32 unk; // = 0x20000
-                } afbc;
-
-                struct {
-                        /* Heck if I know */
-                        u64 unk;
-                        mali_ptr pointer;
-                } chunknown;
-        };
+        struct {
+                /* Stuff related to ARM Framebuffer Compression. When AFBC is enabled,
+                 * there is an extra metadata buffer that contains 16 bytes per tile.
+                 * The framebuffer needs to be the same size as before, since we don't
+                 * know ahead of time how much space it will take up. The
+                 * framebuffer_stride is set to 0, since the data isn't stored linearly
+                 * anymore.
+                 *
+                 * When AFBC is disabled, these fields are zero.
+                 */
+
+                mali_ptr metadata;
+                u32 stride; // stride in units of tiles
+                u32 unk; // = 0x20000
+        } afbc;
 
         mali_ptr framebuffer;
 
diff --git a/src/panfrost/pandecode/decode.c b/src/panfrost/pandecode/decode.c
index 77b83fc8fc5..9c29d870332 100644
--- a/src/panfrost/pandecode/decode.c
+++ b/src/panfrost/pandecode/decode.c
@@ -818,18 +818,11 @@ pandecode_render_target(uint64_t gpu_va, unsigned job_no, const struct bifrost_f
 
                         pandecode_indent--;
                         pandecode_log("},\n");
-                } else {
-                        pandecode_log(".chunknown = {\n");
-                        pandecode_indent++;
-
-                        pandecode_prop("unk = 0x%" PRIx64, rt->chunknown.unk);
-
-                        char *a = pointer_as_memory_reference(rt->chunknown.pointer);
-                        pandecode_prop("pointer = %s", a);
-                        free(a);
-
-                        pandecode_indent--;
-                        pandecode_log("},\n");
+                } else if (rt->afbc.metadata || rt->afbc.stride || rt->afbc.unk) {
+                        pandecode_msg("XXX: AFBC disabled but AFBC field set (0x%lX, 0x%x, 0x%x)\n",
+                                        rt->afbc.metadata,
+                                        rt->afbc.stride,
+                                        rt->afbc.unk);
                 }
 
                 MEMORY_PROP(rt, framebuffer);