RE: [PATCH v3 2/2] pci/aer: interrupt fixup in the quirk

[Po Liu]

Hi Dongdong,

The patch were intend to fixup the NXP layerscape serial SOC and were tested ok.
I am not clear what platform are you trying to fix. 
The problem on your board may be as below comments:


>  -----Original Message-----
>  From: Dongdong Liu [mailto:liudongdong3@xxxxxxxxxx]
>  Sent: Monday, July 04, 2016 4:44 PM
>  To: Po Liu; linux-pci@xxxxxxxxxxxxxxx; linux-arm-
>  kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
>  devicetree@xxxxxxxxxxxxxxx
>  Cc: Bjorn Helgaas; Shawn Guo; Marc Zyngier; Rob Herring; Roy Zang;
>  Mingkai Hu; Stuart Yoder; Yang-Leo Li; Arnd Bergmann; Minghuan Lian;
>  Murali Karicheri; Linuxarm
>  Subject: Re: [PATCH v3 2/2] pci/aer: interrupt fixup in the quirk
>  
>  Hi Po
>  
>  I found a problem with the similar patch. as the below log.
>  
>  [    4.287060] pci 0000:80:00.0: quirk_aer_interrupt dev->irq 416
>  [    4.293778] pcieport 0000:80:00.0: pci_device_probe in
>  [    4.299605] pcieport 0000:80:00.0: of_irq_parse_pci() failed with
>  rc=-22
>  [    4.307209] pcieport 0000:80:00.0: init_service_irqs  dev->irq 0
>  
>  The fucntions are called as below sequence.
>  1. quirk_aer_interrupt, get the aer dev->irq 416.

This code quirk_aer_interrupt() should be run at pci_fixup_device(pci_fixup_final) which is in the pci_bus_add_devices()

>  2. pci_device_probe->of_irq_parse_pci, of_irq_parse_pci() failed, then
>  dev->irq changed to 0.

pci_device_probe->of_irq_parse_pci which in the pci_scan_child_bus() run before  pci_bus_add_devices(). See dw_pcie_host_init().
Apparently , your quirk_aer_interrupt() is running before the dev->irq assignment in the of_irq_parse_pci().

So make sure your configure the quirk_aer_interrupt() run in the FINAL stage in the quirk.c OR check your host driver which you are using.


>  
>  So this patch could not work with aer.
>  
>  Thanks
>  Dongdong
>  å 2016/6/14 16:24, Po Liu åé:
>  > 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@xxxxxxx>
>  > ---
>  > changes for V3:
>  > 	- Move to quirk;
>  > 	- Only correct the irq in RC mode;
>  >
>  >   drivers/pci/quirks.c | 29 +++++++++++++++++++++++++++++
>  >   1 file changed, 29 insertions(+)
>  >
>  > diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index
>  > ee72ebe..8b39cce 100644
>  > --- a/drivers/pci/quirks.c
>  > +++ b/drivers/pci/quirks.c
>  > @@ -25,6 +25,7 @@
>  >   #include <linux/sched.h>
>  >   #include <linux/ktime.h>
>  >   #include <linux/mm.h>
>  > +#include <linux/of_irq.h>
>  >   #include <asm/dma.h>	/* isa_dma_bridge_buggy */
>  >   #include "pci.h"
>  >
>  > @@ -4419,3 +4420,31 @@ static void quirk_intel_qat_vf_cap(struct
>  pci_dev *pdev)
>  >   	}
>  >   }
>  >   DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x443,
>  > quirk_intel_qat_vf_cap);
>  > +
>  > +/* If root port doesn't support MSI/MSI-X/INTx in RC mode,
>  > + * but use standalone irq. Read the device tree for the aer
>  > + * interrupt number.
>  > + */
>  > +static void quirk_aer_interrupt(struct pci_dev *dev) {
>  > +	int ret;
>  > +	u8 header_type;
>  > +	struct device_node *np = NULL;
>  > +
>  > +	/* Only for the RC mode device */
>  > +	pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type);
>  > +	if ((header_type & 0x7F) != PCI_HEADER_TYPE_BRIDGE)
>  > +		return;
>  > +
>  > +	if (dev->bus->dev.of_node)
>  > +		np = dev->bus->dev.of_node;
>  > +
>  > +	if (IS_ENABLED(CONFIG_OF_IRQ) && np) {
>  > +		ret = of_irq_get_byname(np, "aer");
>  > +		if (ret > 0) {
>  > +			dev->no_msi = 1;
>  > +			dev->irq = ret;
>  > +		}
>  > +	}
>  > +}
>  > +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_FREESCALE, PCI_ANY_ID,
>  > +quirk_aer_interrupt);
>  >
>