Re: PCI Express support for 2.4 kernel

Arjan van de Ven
2003-12-15T14:32:24Z

On Mon, Dec 15, 2003 at 03:58:22PM +0200, Vladimir Kondratiev wrote:
> Got it.
> Should I understand it this way: for system with >=1Gb RAM, I will be
> unable to ioremap 256Mb region?
> It looks confusing. On my test system (don't ask details, I am not
> alowed to share this info), I see
> video controller with 256Mb BAR. Does it mean this controller will not
> work as well?

Video memory is generally not ioremap'd by the kernel (it may be mapped into
XFree's address space though)

> I thought about remapping only pages that have actual PCI devices behind,
> but this is problematic: access to config goes not always through
> pci_exp_read_config_xxx and alike, raw access with bus/dev/fn numbers
> used as well. And in 2.6, correct me if I wrong, raw access using
> bus/dev/fn numbers goes to be the only way. Per-device access replaced
> with per-bus, at least.

I would suspect you want to store the ioremap cookie for the config space in
the pci device struct; longer term that struct maybe needs to grow a few
function pointers to access config space too...