panfrost: Add a debug flag to enforce WSI row pitch at import time

So far we assumed tile rows would be tightly packed, so changing the
behavior without introducing a new set of AFBC modifiers is likely
to break some cases where the exported got the stride wrong. That's
still something we would like to enforce in the long run, so let's
start by adding a "PAN_MESA_DEBUG=strict_afbc" flag to exercise the
code supposed to force this behavior.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Tested-by: Eric R. Smith <eric.smith@collabora.com>
Reviewed-by: Eric R. Smith <eric.smith@collabora.com>
Reviewed-by: Mary Guillemard <mary.guillemard@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/35015>

src/gallium/drivers/panfrost/pan_resource.c

@@ -134,6 +134,7 @@ panfrost_resource_from_handle(struct pipe_screen *pscreen,
    struct pan_image_wsi_layout explicit_layout = {
       .offset_B = whandle->offset,
       .row_pitch_B = whandle->stride,
+      .strict = dev->debug & PAN_DBG_STRICT_IMPORT,
    };
 
    rsc->modifier = mod;

src/gallium/drivers/panfrost/pan_screen.c

@@ -72,6 +72,7 @@ static const struct debug_named_value panfrost_debug_options[] = {
    {"nocrc",      PAN_DBG_NO_CRC,     "Disable transaction elimination"},
    {"msaa16",     PAN_DBG_MSAA16,     "Enable MSAA 8x and 16x support"},
    {"linear",     PAN_DBG_LINEAR,     "Force linear textures"},
+   {"strict_import", PAN_DBG_STRICT_IMPORT, "Use the explicit WSI stride and fail if it's not properly aligned"},
    {"nocache",    PAN_DBG_NO_CACHE,   "Disable BO cache"},
    {"dump",       PAN_DBG_DUMP,       "Dump all graphics memory"},
 #ifdef PAN_DBG_OVERFLOW

src/panfrost/lib/pan_util.h

@@ -43,7 +43,7 @@
 #define PAN_DBG_GL3     0x0100
 #define PAN_DBG_NO_AFBC 0x0200
 #define PAN_DBG_MSAA16  0x0400
-/* 0x800 unused */
+#define PAN_DBG_STRICT_IMPORT 0x0800
 #define PAN_DBG_LINEAR   0x1000
 #define PAN_DBG_NO_CACHE 0x2000
 #define PAN_DBG_DUMP     0x4000