Re: Standard driver call to enable/disable PCI ROM

[Russell King <rmk@arm.linux.org.uk>]

On Tue, Aug 19, 2003 at 01:46:43PM -0700, Jon Smirl wrote:
> --- Russell King <rmk@arm.linux.org.uk> wrote:
> > You should use pcibios_resource_to_bus() to convert a resource to a
> > representation suitable for a BAR.
> 
> I've never used pcibios_resource_to_bus(), what's the right way to do this?
> This is a good reason for making this into a common PCI driver function, 
> it will stop people like me from messing up PCI calls.

It's a 2.5/2.6 invention.

Here follows a cut-down version of pci_update_resource() to illustrate
its use when updating up a BAR (see drivers/pci/setup-res.c for the full
version):

static void
pci_update_resource(struct pci_dev *dev, struct resource *res, int resno)
{
        struct pci_bus_region region;

        pcibios_resource_to_bus(dev, &region, res);

        new = region.start | (res->flags & PCI_REGION_FLAG_MASK);

        if (resno < 6) {
                reg = PCI_BASE_ADDRESS_0 + 4 * resno;
        } else if (resno == PCI_ROM_RESOURCE) {
                new |= res->flags & PCI_ROM_ADDRESS_ENABLE;
                reg = dev->rom_base_reg;
        }

        pci_write_config_dword(dev, reg, new);
}

-- 
Russell King (rmk@arm.linux.org.uk)                The developer of ARM Linux
             http://www.arm.linux.org.uk/personal/aboutme.html