[PATCH-for-9.2?,v2,1/2] hw/display/vga: Do not reset 'big_endian_fb' in vga_common_reset()

Commit Message

Philippe Mathieu-Daudé Nov. 29, 2024, 10:17 a.m. UTC

The 'pci-vga' device allow setting a 'big-endian-framebuffer'
property since commit 3c2784fc864 ("vga: Expose framebuffer
byteorder as a QOM property"). Similarly, the 'virtio-vga'
device since commit 8be61ce2ce3 ("virtio-vga: implement
big-endian-framebuffer property").

Both call vga_common_reset() in their reset handler, respectively
pci_secondary_vga_reset() and virtio_vga_base_reset_hold(), which
reset 'big_endian_fb', overwritting the property. This is not
correct: the hardware is expected to keep its configured
endianness during resets.

Move 'big_endian_fb' assignment from vga_common_reset() to
vga_common_init() which is called once when the common VGA state
is initialized.

Signed-off-by: Philippe Mathieu-Daudé <[e-mail]>
---
 hw/display/vga.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Patch

diff --git a/hw/display/vga.c b/hw/display/vga.c
index 892fedc8dce..b074b58c90d 100644
--- a/hw/display/vga.c
+++ b/hw/display/vga.c
@@ -1873,7 +1873,6 @@  void vga_common_reset(VGACommonState *s)
     s->cursor_start = 0;
     s->cursor_end = 0;
     s->cursor_offset = 0;
-    s->big_endian_fb = s->default_endian_fb;
     memset(s->invalidated_y_table, '\0', sizeof(s->invalidated_y_table));
     memset(s->last_palette, '\0', sizeof(s->last_palette));
     memset(s->last_ch_attr, '\0', sizeof(s->last_ch_attr));
@@ -2266,6 +2265,7 @@  bool vga_common_init(VGACommonState *s, Object *obj, Error **errp)
      * all target endian dependencies from this file.
      */
     s->default_endian_fb = target_words_bigendian();
+    s->big_endian_fb = s->default_endian_fb;
 
     vga_dirty_log_start(s);