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Hi, devs |
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|
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Im forwarding this response I got from the author of the grub |
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vga splashimage stuff. Edited for clarity. |
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|
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-- |
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Woodchip |
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|
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---------- Forwarded Message ---------- |
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|
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Subject: Re: grub-0.5.97-vga16.patch |
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Date: Sun, 26 Aug 2001 19:22:22 -0300 (BRST) |
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From: pcpa@×××××××××××××.br |
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To: Donny Davies <woodchip@g.o> |
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|
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Cópia Donny Davies <woodchip@g.o>: |
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> Hi! |
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|
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Hi Donny |
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|
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> Recently our distribution (http://www.gentoo.org - #gentoo on |
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> openprojects) added grub-0.90 to our portage tree. The boot graphic |
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> stuff is I think working well for many people, and I guess we have |
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> you to partially thank for that. Thanks! |
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> |
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:-) |
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> |
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> But the real reason Im mailing you, is when I use it on my notebook PC |
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> (Toshiba Satellite Pro, 4330CDX) I get corruption on the screen |
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> wherever text is supposed to appear. |
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> A couple points.. The splashimage shows up perfectly. I can see our |
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> graphic and it looks very nice. But where there is supposed to be text |
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> like the title= lines, etc, and the ___ | characters (the "box" that |
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> surrounds the menu choices), there is only "snow", like its |
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> somehow getting corrupted. I hope you know what I mean.. I cant |
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> explain it clearer than that. |
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|
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Maybe your notebook bios does not have memory reserved for the |
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vga characters, I guess it probably stores the fonts in the graphics |
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memory, and is being overwritten by the splashimage. It may also be a |
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bug in the bios implementation, but I don´t discard a bug in the grub |
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patch (that happens with your bios), when calling the bios interrupt that |
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should return a pointer to the characters. |
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At some time, I was thinking about adding a option for reading a console |
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font file from the unix filesystem, maybe the problem you are describing is |
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good motive to add such option. |
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|
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> The video chipset is a Chips & Technologies 65554 PCI video chipset, |
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> which is a nice little 2MB video system with support for 24bit color. |
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> |
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> I have in the past (not any more!) used a bootloader from PowerQuest |
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> (BootMagic) that displayed nice boot graphic.. please dont think Im |
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> saying |
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> your patch is bad, and powerquest is good, Im just saying that I know |
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> it |
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> too had to draw text to the screen (I could supply strings to the |
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> program) |
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> which it displayed inside its fancy bootimage. So I think the problem |
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> is |
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> not with my video chipset, but with some code in grub somewhere. |
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> |
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> Also, the way it comes up now, there is black space on all sides. The |
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> main image is "squished" into the middle of my notebook screen, it |
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> doesnt |
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> take up the whole screen space. The bootlader from PowerQuest took up |
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> the whole screen, so again, I think grub could be improved there too. |
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|
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This happens because the grub code, actually, only works in vga 16 colors, |
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and it only runs at 640x480. In my grub TODO list is to add support for |
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VESA modes, that would allow running at any resolution and number of colors. |
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|
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> Another point I wanted to make, was that MS Windows splash screens on |
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> my |
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> notebook, also get "squished" into the middle of the screen, leaving |
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> black |
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> space on all sides. Im only telling you this in hopes that it will |
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> be useful to you for debugging. Maybe this information is good for you to |
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> consider, maybe you dont care about windows or powerquest, thats fine |
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> with me! |
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|
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I know about what you is talking, and it is a very useful information, |
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I won´t say I will work on improving grub soon to fix the problems you |
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described, but it is now in my todo list... |
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|
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> I would be *very* happy to help you in any way possible. I can usually be |
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> found in #gentoo on openprojects.net, with the nickname "woodchip". If yuo |
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> want to get together, and see if we can debug the issue, I will certainly |
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> help you. However I am not a master with debugging tools like gdb |
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> and stuff, so it might be a little slowgoing. |
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|
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gdb won´t help in debugging grub, you probably better with the |
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printf/getkey functions in grub... |
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|
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> The "squished" thing might not be a big priority to you, and thats |
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> also fine by me, but I think that the "corruption where text should be" is |
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> a good thing to work on, because other people will likely have the same |
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> problem, not just myself. |
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|
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If you wish to work on grub, and has some priority on it, I suggest |
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writting code to load console fonts from the filesystem (or compile a static |
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copy of the vga fonts in grub). Also, if you are going to look at it, I |
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believe there is a problem with the interrupt for blinking the cursor. I |
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think it is required C functions to disable/enable cursor blinking, as I |
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think this is the cause of some screen corruptions that may happen when doing |
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some long operation, like loading the kernel or initrd, or just installing |
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grub in the partition. |
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|
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> -- |
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> Cheers, and have a great day! |
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> Donny |
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|
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Paulo |
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|
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------------------------------------------------------- |