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SubjectRe: [PATCH v2] PCI: aardvark: Don't rely on jiffies while holding spinlock
Hi Thomas,

On Fri, Sep 27, 2019 at 10:34:20AM +0200, Thomas Petazzoni wrote:
> Hello Remi,
>
> Thanks for the new iteration!
>
> On Fri, 27 Sep 2019 10:31:42 +0200
> Remi Pommarel <repk@triplefau.lt> wrote:
>
> > diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c
> > index fc0fe4d4de49..ee05ccb2b686 100644
> > --- a/drivers/pci/controller/pci-aardvark.c
> > +++ b/drivers/pci/controller/pci-aardvark.c
> > @@ -175,7 +175,8 @@
> > (PCIE_CONF_BUS(bus) | PCIE_CONF_DEV(PCI_SLOT(devfn)) | \
> > PCIE_CONF_FUNC(PCI_FUNC(devfn)) | PCIE_CONF_REG(where))
> >
> > -#define PIO_TIMEOUT_MS 1
> > +#define PIO_RETRY_CNT 10
> > +#define PIO_RETRY_DELAY 2 /* 2 us*/
>
> So this changes the timeout from 1ms to just 20us, a division by 50
> from the previous timeout value. From my measurements, it could
> sometime take up to 6us from a single PIO read operation to complete,
> which is getting close to the 20us timeout.
>
> Shouldn't PIO_RETRY_CNT be kept at 500, so that we keep using a 1ms
> timeout ?

Damn. You right of course, sorry about that.

Thanks

--
Remi

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