[PATCH 2/2] hw/display/xlnx_dp: Don't abort for unsupported graphics formats

[Peter Maydell <peter.maydell@linaro.org>]

If the guest writes an invalid or unsupported value to the
AV_BUF_FORMAT register, currently we abort().  Instead, log this as
either a guest error or an unimplemented error and continue.

The existing code treats DP_NL_VID_CB_Y0_CR_Y1 as x8b8g8r8
via a "case 0" that does not use the enum constant name for some
reason; we leave that alone beyond adding a comment about the
weird code.

Documentation of this register seems to be at:
https://docs.amd.com/r/en-US/ug1087-zynq-ultrascale-registers/AV_BUF_FORMAT-DISPLAY_PORT-Register

Cc: qemu-stable@nongnu.org
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1415
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 hw/display/xlnx_dp.c | 53 +++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 48 insertions(+), 5 deletions(-)

diff --git a/hw/display/xlnx_dp.c b/hw/display/xlnx_dp.c
index c2bf692e7b1..d8119a56292 100644
--- a/hw/display/xlnx_dp.c
+++ b/hw/display/xlnx_dp.c
@@ -665,14 +665,28 @@ static void xlnx_dp_change_graphic_fmt(XlnxDPState *s)
     case DP_GRAPHIC_BGR888:
         s->g_plane.format = PIXMAN_b8g8r8;
         break;
+    case DP_GRAPHIC_RGBA5551:
+    case DP_GRAPHIC_RGBA4444:
+    case DP_GRAPHIC_8BPP:
+    case DP_GRAPHIC_4BPP:
+    case DP_GRAPHIC_2BPP:
+    case DP_GRAPHIC_1BPP:
+        qemu_log_mask(LOG_UNIMP, "%s: unimplemented graphic format %u",
+                      __func__,
+                      s->avbufm_registers[AV_BUF_FORMAT] & DP_GRAPHIC_MASK);
+        s->g_plane.format = PIXMAN_r8g8b8a8;
+        break;
     default:
-        error_report("%s: unsupported graphic format %u", __func__,
-                     s->avbufm_registers[AV_BUF_FORMAT] & DP_GRAPHIC_MASK);
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid graphic format %u",
+                      __func__,
+                      s->avbufm_registers[AV_BUF_FORMAT] & DP_GRAPHIC_MASK);
+        s->g_plane.format = PIXMAN_r8g8b8a8;
         abort();
     }
 
     switch (s->avbufm_registers[AV_BUF_FORMAT] & DP_NL_VID_FMT_MASK) {
     case 0:
+        /* This is DP_NL_VID_CB_Y0_CR_Y1 ??? */
         s->v_plane.format = PIXMAN_x8b8g8r8;
         break;
     case DP_NL_VID_Y0_CB_Y1_CR:
@@ -681,10 +695,39 @@ static void xlnx_dp_change_graphic_fmt(XlnxDPState *s)
     case DP_NL_VID_RGBA8880:
         s->v_plane.format = PIXMAN_x8b8g8r8;
         break;
+    case DP_NL_VID_CR_Y0_CB_Y1:
+    case DP_NL_VID_Y0_CR_Y1_CB:
+    case DP_NL_VID_YV16:
+    case DP_NL_VID_YV24:
+    case DP_NL_VID_YV16CL:
+    case DP_NL_VID_MONO:
+    case DP_NL_VID_YV16CL2:
+    case DP_NL_VID_YUV444:
+    case DP_NL_VID_RGB888:
+    case DP_NL_VID_RGB888_10BPC:
+    case DP_NL_VID_YUV444_10BPC:
+    case DP_NL_VID_YV16CL2_10BPC:
+    case DP_NL_VID_YV16CL_10BPC:
+    case DP_NL_VID_YV16_10BPC:
+    case DP_NL_VID_YV24_10BPC:
+    case DP_NL_VID_Y_ONLY_10BPC:
+    case DP_NL_VID_YV16_420:
+    case DP_NL_VID_YV16CL_420:
+    case DP_NL_VID_YV16CL2_420:
+    case DP_NL_VID_YV16_420_10BPC:
+    case DP_NL_VID_YV16CL_420_10BPC:
+    case DP_NL_VID_YV16CL2_420_10BPC:
+        qemu_log_mask(LOG_UNIMP, "%s: unimplemented video format %u",
+                      __func__,
+                      s->avbufm_registers[AV_BUF_FORMAT] & DP_NL_VID_FMT_MASK);
+        s->v_plane.format = PIXMAN_x8b8g8r8;
+        break;
     default:
-        error_report("%s: unsupported video format %u", __func__,
-                     s->avbufm_registers[AV_BUF_FORMAT] & DP_NL_VID_FMT_MASK);
-        abort();
+        qemu_log_mask(LOG_UNIMP, "%s: invalid video format %u",
+                      __func__,
+                      s->avbufm_registers[AV_BUF_FORMAT] & DP_NL_VID_FMT_MASK);
+        s->v_plane.format = PIXMAN_x8b8g8r8;
+        break;
     }
 
     xlnx_dp_recreate_surface(s);
-- 
2.43.0