OpenBIOS April 2000

openbios@openbios.org

23 participants
14 discussions

VESA & DMA
by Petazzoni Thomas 07 Apr '00

07 Apr '00

Hi everybody, This has not much to do with the OpenBIOS project, but with low level programming. Everyone here seems to know lot of things in this domain, that's why i'm asking to all of u those questions : 1. Can we setup a VESA 2 (not VESA 3 !) configuration (select video mode, and everything) without making a int 0x10 ? We're programming a protected mode OS, and switching to VM86 sucks. I know it's possible with VESA 3, but with VESA 2 ? If yes, do you have any docs about it ? Is the int 0x10 VESA code specific to each graphic card ? 2. I've got a problem with DMA programming, here's my source : const static DmaChannel dmainfo[] = { { 0x87, 0x00, 0x01 }, { 0x83, 0x02, 0x03 }, { 0x81, 0x04, 0x05 }, { 0x82, 0x06, 0x07 } }; void dma_transfer(int channel, long physical_address, unsigned int length, unsigned sh ort read) { long page, offset; if(channel >= 4) { printk("\nThis function does to manage with channel 4, 5, 6, 7"); return ; } page = physical_address >> 16; offset = physical_address & 0xFFFF; length -= 1; // DIsable IRQs outb(0xFF, 0x21); outb(0xFF, 0xA1); // Masking channel (disable) outb(channel | 4, 0x0A); // Reset Flip-Flop outb(0, 0xC0); // Mode outb( (read ? 0x48 : 0x44) | channel, 0x0B); // Page outb(page, dmainfo[channel].page); // Offset outb(offset & 0xFF, dmainfo[channel].offset); outb((offset >> 8) & 0xFF, dmainfo[channel].offset); // Length outb(length & 0xFF, dmainfo[channel].length); outb((length >> 8) & 0xFF, dmainfo[channel].length); // Unmask outb(channel, 0x0A); // Enabling IRQs outb(0, 0x21); outb(0, 0xA1); } I use it to transfer a sector from the floppy disk. Do you see anything wrong in this code ? The transfer is not made by the floppy, and i don't know why... I don't know if it's in the DMA programming, or in the floppy driver .............. Help ! Thanks, Thomas, from france (If you speak french, you can join the KOS project : http://kos.enix.org) -- PETAZZONI Thomas, coordinateur du projet KOS thomas.petazzoni(a)ifrance.com ICQ : 34937744 Home page : http://perso.worldonline.fr/petazzoni/thomas/ Home Page Projet KOS : http://kos.enix.org - To unsubscribe: send mail to majordomo(a)freiburg.linux.de with 'unsubscribe openbios' in the body of the message

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None
by Kent Nyberg 07 Apr '00

07 Apr '00

I was talking to my friend on irc today.. and i was wondering on thing. When you have written a bad bios and want to copy the normal bios, which i have learned is on a rom, which cant be removed. How do you do that, is it with that switch which says "clear cmos" ?? - To unsubscribe: send mail to majordomo(a)freiburg.linux.de with 'unsubscribe openbios' in the body of the message

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sorry to ask this again
by Ronald G. Minnich 05 Apr '00

05 Apr '00

If someone has the *code* example for calling the vga init on a vga card I could use it. ron - To unsubscribe: send mail to majordomo(a)freiburg.linux.de with 'unsubscribe openbios' in the body of the message

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separate question on PnP and BIOS POST
by Jessen, Per 04 Apr '00

04 Apr '00

All, not exactly an openbios question, but judging by the traffic on the list, I'm sure someone has an answer - I'm trying to add a PnP header structure to a BIOS-image, and need to have the Bios_Connect_Vector and possibly the Static_ Resource_Information_Vector called immediately after POST. This is (as far as I can tell) what a PnP BIOS will do according to the spec (various documents, approx. 1994) The card itself is NOT PnP, but the software on the EPROM will be. Problem is that the BIOS on my system (Abit BP6, Award BIOS) doesn't seem to (1) either recognise the PnP-header in my BIOS-image or (2) doesn't follow the PnP POST-sequence. Does anyone have any pointers for me ? Is it a problem if my BIOS-image is placed at C000 (where the video would normally be found) ? I have all the documents, but it looks like my system BIOS (BP6, Award) isn't behaving as it should ? I had a quick look at the etherboot package, which also has a PnP-header in the BIOS-image - I can't tell if it is being used, though. But the structure looks exactly like what I have coded. any help would be much appreciated! regards, Per Jessen, London - To unsubscribe: send mail to majordomo(a)freiburg.linux.de with 'unsubscribe openbios' in the body of the message

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