From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 13 Oct 2000 18:21:27 +0200 (CEST) From: Geert Uytterhoeven To: Kostas Gewrgiou cc: Michel Dänzer , "Hendricks, Kevin" , Josh Huber , Linux/PowerPC Devel List Subject: Re: dual head r128 In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=ISO-8859-15 Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Thu, 12 Oct 2000, Kostas Gewrgiou wrote: > On Thu, 12 Oct 2000, Michel [iso-8859-1] Dänzer wrote: > > So this code from the current X CVS: > > > > R128ReadBIOS(0x0000, info->VBIOS, R128_VBIOS_SIZE); > > if (info->VBIOS[0] != 0x55 || info->VBIOS[1] != 0xaa) { > > xf86DrvMsg(pScrn->scrnIndex, X_WARNING, > > "Video BIOS not detected in PCI space!\n"); > > > > only checks if there is a ROM, not if it's a BIOS? > > Right, from the pci spec the table is something like this > Offset Length Value Description > 0h 1 55h ROM Signature, byte 1 > 1h 1 AAh ROM Signature, byte 2 > ... > 18h-19h 2 xx Pointer to PCI Data Structure > > PCI Data Structure > Offset Length Description > ... > 14 1 Code Type > .. > > Code Type is 0 for bios and 1 for OF > > So you'll have to add one more test to check for BIOS/OF IIRC, it's also possible to have one ROM that contains both x86 BIOS and F-Code Open Firmware stuff. It may require compression to achieve this due to the limited size to the ROM. I think I saw this on the Firmworks website, an eon ago. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/