Re: [PATCH v17 09/12] PCI/AER: Allow clearing Error Status Register in FF mode

[Kuppuswamy, Sathyanarayanan]

On 3/6/2020 8:04 AM, Bjorn Helgaas wrote:
> On Thu, Mar 05, 2020 at 09:45:46PM -0800, Kuppuswamy, Sathyanarayanan wrote:
> > On 3/3/2020 6:36 PM, sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx wrote:
> > > From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
> > >
> > > As per PCI firmware specification r3.2 System Firmware Intermediary
> > > (SFI) _OSC and DPC Updates ECR
> > > (https://members.pcisig.com/wg/PCI-SIG/document/13563), sec titled "DPC
> > > Event Handling Implementation Note", page 10, Error Disconnect Recover
> > > (EDR) support allows OS to handle error recovery and clearing Error
> > > Registers even in FF mode. So create new API pci_aer_raw_clear_status()
> > > which allows clearing AER registers without FF mode checks.
> > >
> > > Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
> > > ---
> > >    drivers/pci/pci.h      |  2 ++
> > >    drivers/pci/pcie/aer.c | 22 ++++++++++++++++++----
> > >    2 files changed, 20 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
> > > index e57e78b619f8..c239e6dd2542 100644
> > > --- a/drivers/pci/pci.h
> > > +++ b/drivers/pci/pci.h
> > > @@ -655,6 +655,7 @@ extern const struct attribute_group aer_stats_attr_group;
> > >    void pci_aer_clear_fatal_status(struct pci_dev *dev);
> > >    void pci_aer_clear_device_status(struct pci_dev *dev);
> > >    int pci_cleanup_aer_error_status_regs(struct pci_dev *dev);
> > > +int pci_aer_raw_clear_status(struct pci_dev *dev);
> > >    #else
> > >    static inline void pci_no_aer(void) { }
> > >    static inline void pci_aer_init(struct pci_dev *d) { }
> > > @@ -665,6 +666,7 @@ static inline int pci_cleanup_aer_error_status_regs(struct pci_dev *dev)
> > >    {
> > >    	return -EINVAL;
> > >    }
> > > +int pci_aer_raw_clear_status(struct pci_dev *dev) { return -EINVAL; }
>
> > It's missing static specifier. It needs to be fixed. I can fix it in
> > next version.  Bjorn, if there is no need for next version, can you
> > please make this change?
>
> pci_aer_raw_clear_status() is defined in aer.c and called from aer.c
> and edr.c, so I do not think it can be static.  Am I missing
> something?
>
> I have a review/edr branch that I hope becomes what will be applied.
For kernel configs that does not define CONFIG_PCIEAER, it will create 
redefinition error since pci.h can be included in many files.
> Bjorn

--
Sathyanarayanan Kuppuswamy
Linux Kernel Developer