Re: [PATCH V4] PCI: Extend ACS configurability

[Jiri Slaby]

On 25. 09. 24, 7:06, Jiri Slaby wrote:
> > @@ -1047,23 +1066,33 @@ static void pci_std_enable_acs(struct pci_dev 
> > *dev)
> >    */
> >   static void pci_enable_acs(struct pci_dev *dev)
> >   {
> > -    if (!pci_acs_enable)
> > -        goto disable_acs_redir;
> > +    struct pci_acs caps;
> > +    int pos;
> > +
> > +    pos = dev->acs_cap;
> > +    if (!pos)
> > +        return;
> > -    if (!pci_dev_specific_enable_acs(dev))
> > -        goto disable_acs_redir;
> > +    pci_read_config_word(dev, pos + PCI_ACS_CAP, &caps.cap);
> > +    pci_read_config_word(dev, pos + PCI_ACS_CTRL, &caps.ctrl);
> > +    caps.fw_ctrl = caps.ctrl;
> > -    pci_std_enable_acs(dev);
> > +    /* If an iommu is present we start with kernel default caps */
> > +    if (pci_acs_enable) {

AFAIU pci_acs_enable is set from iommus' code via pci_request_acs(). 
Which is much later than when bridges are initialized here, right?

> > +        if (pci_dev_specific_enable_acs(dev))
> > +            pci_std_enable_acs(dev, &caps);

So this is never called, IMO.

> > +    }

thanks,
--
js
suse labs