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

From: Rahul Tanwar
Date: Fri Apr 09 2021 - 06:17:55 EST


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.

Acked-by: Rahul Tanwar <rtanwar@xxxxxxxxxxxxx>

Regards,
Rahul