Re: [PATCH] PCI: dwc/intel-gw: Fix enabling the legacy PCI interrupt lines

From: Lorenzo Pieralisi
Date: Fri Apr 09 2021 - 06:29:57 EST


On Fri, Apr 09, 2021 at 10:17:12AM +0000, Rahul Tanwar wrote:
> On 9/4/2021 4:40 am, Martin Blumenstingl wrote:
> > This email was sent from outside of MaxLinear.
> >
> > Hi Lorenzo,
> >
> > On Tue, Mar 23, 2021 at 12:36 PM Lorenzo Pieralisi
> > <lorenzo.pieralisi@xxxxxxx> wrote:
> > >
> > > On Wed, Jan 06, 2021 at 02:55:40PM +0100, Martin Blumenstingl wrote:
> > > > The legacy PCI interrupt lines need to be enabled using PCIE_APP_IRNEN
> > > > bits 13 (INTA), 14 (INTB), 15 (INTC) and 16 (INTD). The old code
> > however
> > > > was taking (for example) "13" as raw value instead of taking BIT(13).
> > > > Define the legacy PCI interrupt bits using the BIT() macro and then use
> > > > these in PCIE_APP_IRN_INT.
> > > >
> > > > Fixes: ed22aaaede44 ("PCI: dwc: intel: PCIe RC controller driver")
> > > > Signed-off-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>
> > > > ---
> > > > drivers/pci/controller/dwc/pcie-intel-gw.c | 10 ++++++----
> > > > 1 file changed, 6 insertions(+), 4 deletions(-)
> > > >
> > > > diff --git a/drivers/pci/controller/dwc/pcie-intel-gw.c
> > b/drivers/pci/controller/dwc/pcie-intel-gw.c
> > > > index 0cedd1f95f37..ae96bfbb6c83 100644
> > > > --- a/drivers/pci/controller/dwc/pcie-intel-gw.c
> > > > +++ b/drivers/pci/controller/dwc/pcie-intel-gw.c
> > > > @@ -39,6 +39,10 @@
> > > > #define PCIE_APP_IRN_PM_TO_ACK BIT(9)
> > > > #define PCIE_APP_IRN_LINK_AUTO_BW_STAT BIT(11)
> > > > #define PCIE_APP_IRN_BW_MGT BIT(12)
> > > > +#define PCIE_APP_IRN_INTA BIT(13)
> > > > +#define PCIE_APP_IRN_INTB BIT(14)
> > > > +#define PCIE_APP_IRN_INTC BIT(15)
> > > > +#define PCIE_APP_IRN_INTD BIT(16)
> > > > #define PCIE_APP_IRN_MSG_LTR BIT(18)
> > > > #define PCIE_APP_IRN_SYS_ERR_RC BIT(29)
> > > > #define PCIE_APP_INTX_OFST 12
> > > > @@ -48,10 +52,8 @@
> > > > PCIE_APP_IRN_RX_VDM_MSG | PCIE_APP_IRN_SYS_ERR_RC | \
> > > > PCIE_APP_IRN_PM_TO_ACK | PCIE_APP_IRN_MSG_LTR | \
> > > > PCIE_APP_IRN_BW_MGT | PCIE_APP_IRN_LINK_AUTO_BW_STAT | \
> > > > - (PCIE_APP_INTX_OFST + PCI_INTERRUPT_INTA) | \
> > > > - (PCIE_APP_INTX_OFST + PCI_INTERRUPT_INTB) | \
> > > > - (PCIE_APP_INTX_OFST + PCI_INTERRUPT_INTC) | \
> > > > - (PCIE_APP_INTX_OFST + PCI_INTERRUPT_INTD))
> > > > + PCIE_APP_IRN_INTA | PCIE_APP_IRN_INTB | \
> > > > + PCIE_APP_IRN_INTC | PCIE_APP_IRN_INTD)
> > > >
> > > > #define BUS_IATU_OFFSET SZ_256M
> > > > #define RESET_INTERVAL_MS 100
> > >
> > > This looks like a significant bug - which in turn raises the question
> > > on how well this driver has been tested.
> > to give them the benefit of doubt: maybe only MSIs were tested
> >
> > > Dilip, can you review and ACK asap please ?
> > From "Re: MaxLinear, please maintain your drivers was Re: [PATCH]
> > leds: lgm: fix gpiolib dependency" [0]:
> > > Please send any Lightning Mountain SoC related issues email to Rahul
> > > Tanwar (rtanwar@xxxxxxxxxxxxx) and I will ensure that I address the
> > > issues in a timely manner.
> > so I added rtanwar@xxxxxxxxxxxxx to this email
> >
> >
> > Best regards,
> > Martin
> >
> >
> > [0] https://lkml.org/lkml/2021/3/16/282
> > <https://lkml.org/lkml/2021/3/16/282>
>
>
> Dilip has left the org. So not sure how exactly he tested it (maybe only
> MSIs). But i have confirmed it to be a bug. Thanks Martin for fixing it.

Can you take on maintainership for this driver please ?

If yes please send a MAINTAINERS file patch.

Thanks,
Lorenzo

> Acked-by: Rahul Tanwar <rtanwar@xxxxxxxxxxxxx>
>
> Regards,
> Rahul
>
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