Re: [PATCHv5 10/20] PCI: mobiveil: Fix the INTx process errors

From: Lorenzo Pieralisi
Date: Fri Jun 14 2019 - 06:49:01 EST


On Fri, Jun 14, 2019 at 12:38:51PM +0530, Karthikeyan Mitran wrote:
> Hi Lorenzo and Hou Zhiqiang
> PAB_INTP_AMBA_MISC_STAT does have other status in the higher bits, it
> should have been masked before checking for the status

You are the maintainer for this driver, so if there is something to be
changed you must post a patch to that extent, I do not understand what
the above means, write the code to fix it, I won't do it.

I am getting a bit annoyed with this Mobiveil driver so either you guys
sort this out or I will have to remove it from the kernel.

> Acked-by: Karthikeyan Mitran <m.karthikeyan@xxxxxxxxxxxxxx>

Ok I assume this means you tested it but according to what you
say above, are there still issues with this code path ? Should
we update the patch ?

Moreover:

https://kernelnewbies.org/PatchCulture

Please read it and never top-post.

Thanks,
Lorenzo

> On Wed, Jun 12, 2019 at 8:38 PM Lorenzo Pieralisi
> <lorenzo.pieralisi@xxxxxxx> wrote:
> >
> > On Fri, Apr 12, 2019 at 08:36:12AM +0000, Z.q. Hou wrote:
> > > From: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>
> > >
> > > In the loop block, there is not code to update the loop key,
> > > this patch updates the loop key by re-read the INTx status
> > > register.
> > >
> > > This patch also add the clearing of the handled INTx status.
> > >
> > > Note: Need MV to test this fix.
> >
> > This means INTX were never tested and current code handling them is,
> > AFAICS, an infinite loop which is very very bad.
> >
> > This is a gross bug and must be fixed as soon as possible.
> >
> > I want Karthikeyan ACK and Tested-by on this patch.
> >
> > Lorenzo
> >
> > > Fixes: 9af6bcb11e12 ("PCI: mobiveil: Add Mobiveil PCIe Host Bridge IP driver")
> > > Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>
> > > Reviewed-by: Minghuan Lian <Minghuan.Lian@xxxxxxx>
> > > Reviewed-by: Subrahmanya Lingappa <l.subrahmanya@xxxxxxxxxxxxxx>
> > > ---
> > > V5:
> > > - Corrected and retouched the subject and changelog.
> > >
> > > drivers/pci/controller/pcie-mobiveil.c | 13 +++++++++----
> > > 1 file changed, 9 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/drivers/pci/controller/pcie-mobiveil.c b/drivers/pci/controller/pcie-mobiveil.c
> > > index 4ba458474e42..78e575e71f4d 100644
> > > --- a/drivers/pci/controller/pcie-mobiveil.c
> > > +++ b/drivers/pci/controller/pcie-mobiveil.c
> > > @@ -361,6 +361,7 @@ static void mobiveil_pcie_isr(struct irq_desc *desc)
> > > /* Handle INTx */
> > > if (intr_status & PAB_INTP_INTX_MASK) {
> > > shifted_status = csr_readl(pcie, PAB_INTP_AMBA_MISC_STAT);
> > > + shifted_status &= PAB_INTP_INTX_MASK;
> > > shifted_status >>= PAB_INTX_START;
> > > do {
> > > for_each_set_bit(bit, &shifted_status, PCI_NUM_INTX) {
> > > @@ -372,12 +373,16 @@ static void mobiveil_pcie_isr(struct irq_desc *desc)
> > > dev_err_ratelimited(dev, "unexpected IRQ, INT%d\n",
> > > bit);
> > >
> > > - /* clear interrupt */
> > > - csr_writel(pcie,
> > > - shifted_status << PAB_INTX_START,
> > > + /* clear interrupt handled */
> > > + csr_writel(pcie, 1 << (PAB_INTX_START + bit),
> > > PAB_INTP_AMBA_MISC_STAT);
> > > }
> > > - } while ((shifted_status >> PAB_INTX_START) != 0);
> > > +
> > > + shifted_status = csr_readl(pcie,
> > > + PAB_INTP_AMBA_MISC_STAT);
> > > + shifted_status &= PAB_INTP_INTX_MASK;
> > > + shifted_status >>= PAB_INTX_START;
> > > + } while (shifted_status != 0);
> > > }
> > >
> > > /* read extra MSI status register */
> > > --
> > > 2.17.1
> > >
>
>
>
> --
> Thanks,
> Regards,
> Karthikeyan Mitran
>
> --
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