Re: [PATCH v2 1/2] PCI: dra7xx: Fix legacy INTD IRQ handling

From: Kishon Vijay Abraham I
Date: Thu Jan 04 2018 - 08:34:47 EST


Hi,

On Thursday 04 January 2018 11:38 AM, Kishon Vijay Abraham I wrote:
>
>
> On Friday 29 December 2017 05:11 PM, Vignesh R wrote:
>> Legacy INTD IRQ handling is broken on dra7xx due to fact that driver
>> uses hwirq in range of 1-4 for INTA, INTD whereas IRQ domain is of size
>> 4 which is numbered 0-3. Therefore when INTD IRQ line is used with
>> pci-dra7xx driver following warning is seen:
>>
>> WARNING: CPU: 0 PID: 1 at kernel/irq/irqdomain.c:342 irq_domain_associate+0x12c/0x1c4
>> error: hwirq 0x4 is too large for dummy
>>
>> Fix this by using pci_irqd_intx_xlate() helper to translate the INTx 1-4
>> range into the 0-3 as done in other PCIe drivers.
>>
>> Suggested-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
>> Reported-by: Chris Welch <Chris.Welch@xxxxxxxxxxxxxxxxxx>
>> Signed-off-by: Vignesh R <vigneshr@xxxxxx>
>
> Acked-by: Kishon Vijay Abraham I <kishon@xxxxxx>
>> ---
>> drivers/pci/dwc/pci-dra7xx.c | 3 ++-
>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/pci/dwc/pci-dra7xx.c b/drivers/pci/dwc/pci-dra7xx.c
>> index 58aed0896468..892f93910012 100644
>> --- a/drivers/pci/dwc/pci-dra7xx.c
>> +++ b/drivers/pci/dwc/pci-dra7xx.c
>> @@ -226,6 +226,7 @@ static int dra7xx_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
>>
>> static const struct irq_domain_ops intx_domain_ops = {
>> .map = dra7xx_pcie_intx_map,
>> + .xlate = pci_irqd_intx_xlate,

Looking at this again, I think the mapping should be done in device tree using
the interrupt-map property.

Lorenzo, can you hold merging this patch till we verify using the dt approach?

Thanks
Kishon