Kernel command line for a specific framebuffer console driver

Kernel command line for a specific framebuffer console driver

[Juergen Beisert]

Hi,

does someone know how to forward a kernel command line option to configure the 
AMD Geode GX1 framebuffer?

I tried with "video=gx1fb:1024x768-16@60" but it does not work. On another 
machine with an SIS framebuffer the line "video=sisfb:1280x1024-8@60" works 
as expected.

Any ideas?

Juergen

Re: Kernel command line for a specific framebuffer console driver

[Alexey Dobriyan]

On Fri, Jan 12, 2007 at 01:43:42PM +0100, Juergen Beisert wrote:
> does someone know how to forward a kernel command line option to configure the
> AMD Geode GX1 framebuffer?
>
> I tried with "video=gx1fb:1024x768-16@60" but it does not work. On another
> machine with an SIS framebuffer the line "video=sisfb:1280x1024-8@60" works
> as expected.
>
> Any ideas?

Yes. You try this patch and report whether it works or not.

--- a/drivers/video/geode/gx1fb_core.c
+++ b/drivers/video/geode/gx1fb_core.c
@@ -401,6 +401,30 @@ static void gx1fb_remove(struct pci_dev 
 	framebuffer_release(info);
 }
 
+#ifndef MODULE
+static void __init gx1fb_setup(char *options)
+{
+	char *this_opt;
+
+	if (!options || !*options)
+		return;
+
+	while ((this_opt = strsep(&options, ","))) {
+		if (!*this_opt)
+			continue;
+
+		if (!strncmp(this_opt, "mode:", 5))
+			strlcpy(mode_option, this_opt + 5, sizeof(mode_option));
+		else if (!strncmp(this_opt, "crt:", 4))
+			crt_option = !!simple_strtoul(this_opt + 4, NULL, 0);
+		else if (!strncmp(this_opt, "panel:", 6))
+			strlcpy(panel_option, this_opt + 6, sizeof(panel_option));
+		else
+			strlcpy(mode_option, this_opt, sizeof(mode_option));
+	}
+}
+#endif
+
 static struct pci_device_id gx1fb_id_table[] = {
 	{ PCI_VENDOR_ID_CYRIX, PCI_DEVICE_ID_CYRIX_5530_VIDEO,
 	  PCI_ANY_ID, PCI_ANY_ID, PCI_BASE_CLASS_DISPLAY << 16,
@@ -420,8 +444,11 @@ static struct pci_driver gx1fb_driver = 
 static int __init gx1fb_init(void)
 {
 #ifndef MODULE
-	if (fb_get_options("gx1fb", NULL))
+	char *option = NULL;
+
+	if (fb_get_options("gx1fb", &option))
 		return -ENODEV;
+	gx1fb_setup(option);
 #endif
 	return pci_register_driver(&gx1fb_driver);
 }

Re: Kernel command line for a specific framebuffer console driver

[Juergen Beisert]

Hi Alexey,

On Friday 12 January 2007 20:36, Alexey Dobriyan wrote:
> On Fri, Jan 12, 2007 at 01:43:42PM +0100, Juergen Beisert wrote:
> > does someone know how to forward a kernel command line option to
> > configure the AMD Geode GX1 framebuffer?
> >
> > I tried with "video=gx1fb:1024x768-16@60" but it does not work. On
> > another machine with an SIS framebuffer the line
> > "video=sisfb:1280x1024-8@60" works as expected.
> >
> > Any ideas?
>
> Yes. You try this patch and report whether it works or not.

Thank you very much. Yes it works. I tried these kernel parameters:

1) video=gx1fb:mode:1280x1024-16@60,crt:1
  -> CRT was active, 160x64 console
2) video=gx1fb:mode:1024x768-16@60,crt:1
  -> CRT was active, 128x48 console
3) video=gx1fb:mode:800x600-16@60,crt:0,panel:800x600
  -> CRT was disabled, 100x37 console
4) video=gx1fb:mode:1024x768-16@60,crt:0,panel:800x600
  -> CRT was disabled, 80x25 console

Sorry, I have no flatpanel, so I cannot test if the "panel" option works 
correctly. But somethings changes when I tried different values (see 3 and 
4).

Regards
Juergen