PCI VGA card works too

[Li-Ta Lo]

Hello,

I just made PCI vga cards works too. The problem is if the PCI card
does not claim PCI IO resource, the bridge's IO enable bit in the
command register is not enabled. Even with the legacy forwarding
enabled in the bridge control, it still does not forward any
legacy vga io. So the pci_bus_enable_resources() should be

void pci_bus_enable_resources(struct device *dev)
{
    uint16_t ctrl;

/* enable IO in command register if there is VGA card
     * connected with (even it does not claim IO resource) */
    if (dev->link[0].bridge_ctrl & PCI_BRIDGE_CTL_VGA)
    	dev->command |= PCI_COMMAND_IO;

ctrl = pci_read_config16(dev, PCI_BRIDGE_CONTROL);
    ctrl |= dev->link[0].bridge_ctrl;
    ctrl |= (PCI_BRIDGE_CTL_PARITY + PCI_BRIDGE_CTL_SERR); /* error check
*/
    printk_debug("%s bridge ctrl <- %04x\n", dev_path(dev), ctrl);
    pci_write_config16(dev, PCI_BRIDGE_CONTROL, ctrl);

pci_dev_enable_resources(dev);

enable_childrens_resources(dev);
}