Re: PCI support

[Marco Gerards]

Robert Millan <address@hidden> writes:

> On Mon, Jan 28, 2008 at 03:03:33PM +0100, Marco Gerards wrote:
>> 
>> I wanted to wait with this patch until the ATA driver is adapted.  But
>> I won't have time for that this week.  So I can better get this
>> committed and people working on this ;-).  There is some code for ATA,
>> but it was not tested yet.  The main problem here is qemu.
>> 
>> Does someone know if it is possible, at all, to have ATA devices
>> showing up as non-legacy PCI devices in Qemu?  IDE interfaces are
>> placed (and locked) in Legacy mode, meaning default IRQs and IO ports
>> are used.  This means just our old ISA code will be used.  To support
>> non-legacy modes, it would be nice if I could do some testing.  Does
>> someone have suggestions?
>
> Try:
>
> --- qemu-0.9.0+20070816/hw/pc.c~        2007-06-06 18:26:13.000000000 +0200
> +++ qemu-0.9.0+20070816/hw/pc.c 2008-01-28 18:25:00.000000000 +0100
> @@ -676,6 +676,8 @@
>      qemu_irq *cpu_irq;
>      qemu_irq *i8259;
>
> +    pci_enabled = 1;
> +
>      linux_boot = (kernel_filename != NULL);
>
>      /* init CPUs */

The problem isn't that PCI isn't enabled.  The problem is that IDE
devices are in legacy mode...

So you do see the IDE interface using lspci.  One bit can be used to
check if the device is in legacy mode or not.  If it indicates legacy
mode, you have to use some fixed ports that are already present in
ata.c.  Otherwise, you can query the port ranges from the PCI device.
Qemu only supports the latter mode, as it seems.

--
Marco