Messages in this thread | | | Date | Thu, 17 Sep 2015 10:13:21 -0700 | From | David Daney <> | Subject | Re: [PATCH 2/6] PCI: generic: Only fixup irqs for bus we are creating. |
| |
On 09/16/2015 03:32 AM, Lorenzo Pieralisi wrote: > On Tue, Sep 15, 2015 at 06:49:24PM +0100, David Daney wrote: >> On 09/15/2015 10:36 AM, Will Deacon wrote: >>> Hi David, >>> >>> On Sat, Sep 12, 2015 at 12:21:55AM +0100, David Daney wrote: >>>> From: David Daney <david.daney@cavium.com> >>>> >>>> Use pci_walk_bus() to restrict the fixup irq actions to only the bus >>>> being created. >>>> >>>> If we create multiple buses with pci-host-generic, or there are buses >>>> created by other drivers, we don't want to call pci_fixup_irqs() which >>>> operates on all devices, not just the devices on the bus being added. >>>> The consequence is that either the fixups are done more than once, or >>>> in some cases incorrect fixups could be applied. >>>> >>>> Signed-off-by: David Daney <david.daney@cavium.com> >>>> --- >>>> drivers/pci/host/pci-host-generic.c | 8 +++++++- >>>> 1 file changed, 7 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/drivers/pci/host/pci-host-generic.c b/drivers/pci/host/pci-host-generic.c >>>> index 265dd25..a0fb241 100644 >>>> --- a/drivers/pci/host/pci-host-generic.c >>>> +++ b/drivers/pci/host/pci-host-generic.c >>>> @@ -205,6 +205,12 @@ static int gen_pci_parse_map_cfg_windows(struct gen_pci *pci) >>>> return 0; >>>> } >>>> >>>> +static int gen_pci_fixup_irq_cb(struct pci_dev *dev, void *arg) >>>> +{ >>>> + pdev_fixup_irq(dev, pci_common_swizzle, of_irq_parse_and_map_pci); >>>> + return 0; >>>> +} >>>> + >>>> static int gen_pci_probe(struct platform_device *pdev) >>>> { >>>> int err; >>>> @@ -262,7 +268,7 @@ static int gen_pci_probe(struct platform_device *pdev) >>>> return -ENODEV; >>>> } >>>> >>>> - pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci); >>>> + pci_walk_bus(bus, gen_pci_fixup_irq_cb, NULL); >>> >>> Any chance we could put something in the core PCI code for this? I think >>> any host controller wanting to work with arm64 is potentially going to >>> run into the same problem. >> >> Good idea. >> >> I will move the walking code into setup-irq.c (the current home of >> pci_fixup_irqs()), and make it part of patch 1/6. > > For arm64 we could even compile out pci_fixup_irqs() since the IRQ mapping > is done in pcibios_add_device() through DT, I agree on CONFIG_ARM this > needs fixing though, so yes, make it common code and patch all host > controllers that make use of pci_fixup_irqs() since that's a common > issue as far as I can see (ARM pcibios works around it by having a > IRQ mapping function per bus and it provides an API to initialize > multiple host controllers at once and fixing up IRQs before devices > are added, still, for host controllers that do not use that > functionality - eg drivers/pci/host/pcie-designware.c - if there are > multiple host controllers instances we run into the same problem).
Patching up other PCI bus drivers would be deferred to a different patch set, as I have no way to test it.
> > Side note: do you have any PCI host controller where mapping IRQs through > of_irq_parse_and_map_pci() does not work ? If yes, why ? >
The of_irq_parse_and_map_pci() call in arch/arm64/kernel/pci.c (pcibios_add_device) seems to work for me.
I did send a patch recently to make it quite emitting erroneous error messages for PCI devices that have no irq pin.
David Daney
| |