Re: [Qemu-devel] [RFC PATCH 1/3] tests: add libpci qtest library

[Andreas Färber]

Am 16.04.2012 11:14, schrieb Stefan Hajnoczi:
> On Sat, Apr 14, 2012 at 12:32:00PM +0000, Blue Swirl wrote:
>> On Fri, Apr 13, 2012 at 14:27, Stefan Hajnoczi
>> <address@hidden> wrote:
>>> This patch adds a common PCI bus driver library which works for
>>> i386/x86-64 targets.  Tests can use the library to probe for PCI
>>> devices, map BARs, and access configuration space.
>>
>> I guess we have almost identical code in SeaBIOS, OpenBIOS, various OS
>> and maybe userland PCI tools. Would it be possible to reduce NIH
>> somewhere?
> 
> Probably not given how small these functions are and how they use glib
> assert calls because they are part of tests.
> 
>>> +void pci_config_writel(PciDevice *dev, unsigned int offset, uint32_t l)
>>> +{
>>> +    pci_config_setup(dev, offset);
>>> +    outl(PCI_CONFIG_DATA, l);
>>> +}
>>
>> All code above is specific to i440fx or similar PCI bridges, other
>> bridges may use different config space access methods. If we want to
>> share the rest for example with Sparc64 or PPC, the above would need
>> to be changed. How about splitting the above to a separate file? It
>> could be done later too.
> 
> Yes, it's only i440fx for now.  I think it makes sense to move it later
> since we have no non-x86 qtests yet.

As stated before, I'm very grateful of your work in this area. I'd be
very interested in having PCI-based tests for the PReP devices we're
introducing - some outline of how non-x86 targets are supposed to fit in
here would be appreciated. For example, would we want to rename the file
to libpci-i440fx.c and have libpci.h be a common interface for multiple
implementations? Or are you expecting some #ifdef TARGET_FOO inside
libpci.c?

Thanks,
Andreas

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