v2.4.21 vesafb oddity (fwd)
From: Geert Uytterhoeven <geert@linux-m68k.org>
Date: 2003-06-27 08:30:06
---------- Forwarded message ---------- Date: Fri, 27 Jun 2003 14:17:14 +0600 (GMT-6) From: ishan_jayawardena@yahoo.co.uk To: geert@linux-m68k.org Cc: alan@lxorguk.ukuu.org.uk Subject: v2.4.21 vesafb oddity Greetings, Thanks for taking the time to read this. At least for the VESAFB driver in 2.4.21, the framebuffer size is being miscalculated. This yields wildly different values with different modes. e.g. (The memory on the card is 2M)
--- fbdmesg-2.4.21 Fri Jun 27 00:01:53 2003
+++ fbdmesg-2.4.21-ac2 Fri Jun 27 00:08:52 2003
. . .
-vesafb: framebuffer at 0xf4000000, mapped to 0xc4800000, size 12288k
+vesafb: framebuffer at 0xf4000000, mapped to 0xc4800000, size 2048k
vesafb: mode is 1024x768x16, linelength=2048, pages=0
vesafb: protected mode interface info at c000:5db2
. . .
In mode 791 (1024x768x16bpp) the stock kernel reports 12288k, while the -ac kernel correctly reports 2048k. In lower modes (800x600x16bpp etc.) both kernels report values less than 2048k (1875k, etc.). The patch below reverts this back to the v2.2 behaviour. I'm afraid I just don't know the time at which this anomaly began, except that 2.4.20 (-acN and stock) was fine.
--- linux/drivers/video/vesafb.c.1 Fri Jun 27 00:18:25 2003
+++ linux/drivers/video/vesafb.c Fri Jun 27 00:27:29 2003@@ -520,7 +520,7 @@ int __init vesafb_init(void) video_width = screen_info.lfb_width; video_height = screen_info.lfb_height; video_linelength = screen_info.lfb_linelength; - video_size = screen_info.lfb_width * screen_info.lfb_height * video_bpp; + video_size = screen_info.lfb_size * 65536; video_visual = (video_bpp == 8) ? FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_TRUECOLOR;
--
"Lies, lies, all is lies! Yet beyond I tell you, beauteous and eternal
stands the Truth, Macumazahn."
- Zikali
-------------------------------------------------------
This SF.Net email is sponsored by: INetU
Attention Web Developers & Consultants: Become An INetU Hosting Partner.
Refer Dedicated Servers. We Manage Them. You Get 10% Monthly Commission!
INetU Dedicated Managed Hosting http://www.inetu.net/partner/index.php