RE: [PATCH v5 3/3] pci:aer: add support aer interrupt with none MSI/MSI-X/INTx mode

Po Liu
2016-09-18T03:37:36Z

Hi Shawn,

> -----Original Message-----
> From: Shawn Guo [mailto:shawnguo@kernel.org]
> Sent: Sunday, September 18, 2016 8:52 AM
> To: Po Liu
> Cc: linux-pci@vger.kernel.org; linux-arm-kernel@lists.infradead.org;
> linux-kernel@vger.kernel.org; devicetree@vger.kernel.org; Roy Zang; Arnd
> Bergmann; Marc Zyngier; Stuart Yoder; Leo Li; M.H. Lian; Murali
> Karicheri; Bjorn Helgaas; Mingkai Hu
> Subject: Re: [PATCH v5 3/3] pci:aer: add support aer interrupt with none
> MSI/MSI-X/INTx mode
>
> On Tue, Sep 13, 2016 at 12:40:59PM +0800, Po Liu wrote:
> > On some platforms, root port doesn't support MSI/MSI-X/INTx in RC mode.
> > When chip support the aer interrupt with none MSI/MSI-X/INTx mode,
> > maybe there is interrupt line for aer pme etc. Search the interrupt
> > number in the fdt file. Then fixup the dev->irq with it.
> >
> > Signed-off-by: Po Liu <po.liu@nxp.com>
>
> Will the new kernel work with existing/old DTB? I'm trying to
> understand the dependency between driver and DTS changes.

Yes, We've never use name 'intr' before. So we remove it is ok.
'aer' is a dts name for researching it's true interrupt number by kernel. This patch is first time to use name 'aer'. So it must be compatible with existing/old DTB.

>
> Shawn
>
> > ---
> > changes for v5:
> > - Add clear 'aer' interrup-names description
> >
> > .../devicetree/bindings/pci/layerscape-pci.txt | 11 +++++---
> > drivers/pci/pcie/portdrv_core.c | 31
> +++++++++++++++++++---
> > 2 files changed, 35 insertions(+), 7 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/pci/layerscape-pci.txt
> > b/Documentation/devicetree/bindings/pci/layerscape-pci.txt
> > index 41e9f55..101d0a7 100644
> > --- a/Documentation/devicetree/bindings/pci/layerscape-pci.txt
> > +++ b/Documentation/devicetree/bindings/pci/layerscape-pci.txt
> > @@ -18,8 +18,10 @@ Required properties:
> > - reg: base addresses and lengths of the PCIe controller
> > - interrupts: A list of interrupt outputs of the controller. Must
> contain an
> > entry for each entry in the interrupt-names property.
> > -- interrupt-names: Must include the following entries:
> > - "intr": The interrupt that is asserted for controller interrupts
> > +- interrupt-names: It may be include the following entries:
> > + "aer": The interrupt that is asserted for aer interrupt
> > + "pme": The interrupt that is asserted for pme interrupt
> > + ......
> > - fsl,pcie-scfg: Must include two entries.
> > The first entry must be a link to the SCFG device node
> > The second entry must be '0' or '1' based on physical PCIe
> controller index.
> > @@ -35,8 +37,9 @@ Example:
> > reg = <0x00 0x03400000 0x0 0x00010000 /* controller
> registers */
> > 0x40 0x00000000 0x0 0x00002000>; /* configuration
> space */
> > reg-names = "regs", "config";
> > - interrupts = <GIC_SPI 177 IRQ_TYPE_LEVEL_HIGH>; /*
> controller interrupt */
> > - interrupt-names = "intr";
> > + interrupts = <GIC_SPI 176 IRQ_TYPE_LEVEL_HIGH>, /* aer
> interrupt */
> > + <GIC_SPI 177 IRQ_TYPE_LEVEL_HIGH>; /* pme interrupt */
> > + interrupt-names = "aer", "pme";
> > fsl,pcie-scfg = <&scfg 0>;
> > #address-cells = <3>;
> > #size-cells = <2>;
> > diff --git a/drivers/pci/pcie/portdrv_core.c
> > b/drivers/pci/pcie/portdrv_core.c index e9270b4..7c4943d 100644
> > --- a/drivers/pci/pcie/portdrv_core.c
> > +++ b/drivers/pci/pcie/portdrv_core.c
> > @@ -16,6 +16,7 @@
> > #include <linux/slab.h>
> > #include <linux/pcieport_if.h>
> > #include <linux/aer.h>
> > +#include <linux/of_irq.h>
> >
> > #include "../pci.h"
> > #include "portdrv.h"
> > @@ -200,6 +201,28 @@ static int pcie_port_enable_msix(struct pci_dev
> > *dev, int *vectors, int mask) static int init_service_irqs(struct
> > pci_dev *dev, int *irqs, int mask) {
> > int i, irq = -1;
> > + int ret;
> > + struct device_node *np = NULL;
> > +
> > + for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++)
> > + irqs[i] = 0;
> > +
> > + if (dev->bus->dev.of_node)
> > + np = dev->bus->dev.of_node;
> > +
> > + /* If root port doesn't support MSI/MSI-X/INTx in RC mode,
> > + * request irq for aer
> > + */
> > + if (IS_ENABLED(CONFIG_OF_IRQ) && np &&
> > + (mask & PCIE_PORT_SERVICE_PME)) {
> > + ret = of_irq_get_byname(np, "aer");
> > + if (ret > 0) {
> > + irqs[PCIE_PORT_SERVICE_AER_SHIFT] = ret;
> > + if (dev->irq)
> > + irq = dev->irq;
> > + goto no_msi;
> > + }
> > + }
> >
> > /*
> > * If MSI cannot be used for PCIe PME or hotplug, we have to use
> @@
> > -225,11 +248,13 @@ static int init_service_irqs(struct pci_dev *dev,
> int *irqs, int mask)
> > irq = dev->irq;
> >
> > no_msi:
> > - for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++)
> > - irqs[i] = irq;
> > + for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++) {
> > + if (!irqs[i])
> > + irqs[i] = irq;
> > + }
> > irqs[PCIE_PORT_SERVICE_VC_SHIFT] = -1;
> >
> > - if (irq < 0)
> > + if (irq < 0 && irqs[PCIE_PORT_SERVICE_AER_SHIFT] < 0)
> > return -ENODEV;
> > return 0;
> > }
> > --
> > 2.1.0.27.g96db324
> >
> >
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