On Wed, Feb 08, 2017 at 01:49:20PM +0100, Alexander Gordeev wrote:
> On Sat, Jan 28, 2017 at 12:10:41PM +0100, Andrew Jones wrote:
> > How about just this instead (untested)
> >
> > bool pci_bar_is_valid(pcidevaddr_t dev, int bar_num)
> > {
> > assert(bar_num >= 0 && bar_num < PCI_BAR_NUM);
> > if (bar_num > 0 && pci_bar_is64(dev, bar_num - 1))
> > return pci_bar_is_valid(dev, bar_num - 1);
> > return pci_bar_size(dev, bar_num);
> > }
>
> This one can not distinguish between PCI_BASE_ADDRESS_* flags
> and address bits of high part of a 64 bit address.
>
> However, it seems a newly introduced pci_dev::resource[] can
> be used for that.
Hi Andrew,
Although using pci_dev::resource[] is possible I do not like a
result for various reasons. I.e. I anticipate these:
- pci_bar_get/set_addr() logic will get quite cryptic;
- mismatch between pci_dev::resource[] 64 bit size and
32 bit BAR size. While it is okay right now it will
be confusing once pci_dev::resource[] are reused as
BAR validity flags;
- architecture specific pci_probe() reworked to seed
pci_dev::resource[] (and being invoked on all archs);
Overall, the current compact implementetion is going to turn
into a framework with not so obvious logic.
I suggest just polish v1 or drop the idea of checking BARs
altogether.
Thoughts?
> > Thanks,
> > drew
