On 06/10/2021 13:24, Laurent Vivier wrote:
This is where it becomes a bit trickier, since technically booting Linux with
-kernel you can use
any supported values as long as everything fits in the video RAM which is why
there isn't currently
a hard-coded list :)
We need the list of "supported values". I don't want to read the code or try
values combination
until it works.
In a perfect world, I would like to be able to use any value I want with
"-kernel".
For instance I was using "-g 1200x800x24" and it was working fine.
Now I have:
qemu-system-m68k: unknown display mode: width 1200, height 800, depth 24
If it's not possible (because the original hardware cannot provide it, and we
don't know the base
address or things like that), we don't need the list of the display id, but the
list of available
modes: (width,height,depth).
Rougly, something like:
qemu-system-m68k: unknown display mode: width 1200, height 800, depth 24
Available modes:
1152x870x8
1152x870x4
1152x870x2
1152x870x1
800x600x24
800x600x8
800x600x4
800x600x2
800x600x1
640x480x24
640x480x8
640x480x4
640x480x2
640x480x1
diff --git a/hw/display/macfb.c b/hw/display/macfb.c
index 5b8812e9e7d8..4b352eb89c3f 100644
--- a/hw/display/macfb.c
+++ b/hw/display/macfb.c
@@ -438,6 +438,26 @@ static MacFbMode *macfb_find_mode(MacfbDisplayType
display_type,
return NULL;
}
+static gchar *macfb_mode_list(void)
+{
+ gchar *list = NULL;
+ gchar *mode;
+ MacFbMode *macfb_mode;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(macfb_mode_table); i++) {
+ macfb_mode = &macfb_mode_table[i];
+
+ mode = g_strdup_printf(" %dx%dx%d\n", macfb_mode->width,
+ macfb_mode->height, macfb_mode->depth);
+ list = g_strconcat(mode, list, NULL);
+ g_free(mode);
+ }
+
+ return list;
+}
+
+
static void macfb_update_display(void *opaque)
{
MacfbState *s = opaque;
@@ -620,8 +640,13 @@ static bool macfb_common_realize(DeviceState *dev,
MacfbState *s, Error **errp)
s->mode = macfb_find_mode(s->type, s->width, s->height, s->depth);
if (!s->mode) {
+ gchar *list;
error_setg(errp, "unknown display mode: width %d, height %d, depth
%d",
s->width, s->height, s->depth);
+ list = macfb_mode_list();
+ error_append_hint(errp, "Available modes:\n%s", list);
+ g_free(list);
+
return false;
}
Hi Laurent,
Thanks for the example - I can certainly squash this into patch 8.
As for allowing extra resolutions via -kernel, since the check is being done in
macfb_common_realize() then it would be possible to add a qdev property that only
gets set when -kernel is used on the command line which bypasses the mode check if
you prefer?
I'm not sure that your existing example of "-g 1200x800x24" (or indeed any resolution
with 24-bit depth) with -kernel will still work after this patchset given that the
24-bit encoding scheme has changed. Presumably this would also need a corresponding
change in the bootinfo/kernel framebuffer/X configuration somewhere?
ATB,
Mark.
