VGA support

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Revision as of 23:14, 10 August 2005 by Ollie (talk | contribs)
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There are two kinds of VGA support we have

    1. onboard vga
    2. addon card.

You need to enable two CONFIG options in your Mainboard

    #VGA Console
    option CONFIG_PCI_ROM_RUN=1

CONFIG_PCI_ROM_RUN will use the embedded x86 emulator to run the BIOS image in the expansion ROM of PCI device. CONFIG_CONSOLE_VGA will redirect console messages to the VGA screen once VGA card is initialized.

For addon VGA cards, you don't have to do anyting else besides these two CONFIG options. If your mainboard has an onboard VGA chip and you insert another VGA addon card, the addon VGA card will be used instead of the onboard VGA chip.

If you want to use the onboard VGA chip, you have to do the following in additional to the CONFIG options described above.

1. in MB You need to specify for your onboard VGA

                                      device pci 9.0 on  # PCI
                                              chip drivers/pci/onboard
                                                      device pci 9.0 on end
                                                      register "rom_address" = "0xfff80000" #512k image
                                                      #register "rom_address" = "0xfff00000" #1M image

Please make sure the device num should be right. Otherwise it can not get exact ROM address.

2. You still need to modify your target in normal section

      romimage "normal"
      #       48K for SCSI FW or ATI ROM
      option ROM_SIZE = 475136

It will leave space for vga option rom in flash.

3. So at last for your linuxbios.rom, you should do

     cat atix.rom linuxbios.rom > final_linuxbios.rom

you need to make sure the final_linuxbios.rom size is 512k or 1M.

please use dd to get you atix.rom when running Normal BIOS.