Re: [PATCH V2 3/5] PCI: xilinx: Modifying AXI PCIe Host Bridge driver to work on both Zynq and Microblaze

[Michal Simek <michal.simek@xilinx.com>]

On 12.1.2016 23:27, Arnd Bergmann wrote:
> On Tuesday 12 January 2016 23:06:11 Bharat Kumar Gogada wrote:
>> Modifying Xilinx AXI PCIe Host Bridge Soft IP driver to work on both
>> Zynq and Microblaze Architectures.
>> With these modifications drivers/pci/host/pcie-xilinx.c, will
>> work on both Zynq and Microblaze Architectures.
>>
>> Signed-off-by: Bharat Kumar Gogada <bharatku@xilinx.com>
>> Signed-off-by: Ravi Kiran Gummaluri <rgummal@xilinx.com>
> 
> I think this patch should be split into three, as you are doing three
> unrelated things here.
> 
>> ---
>> Changes:
>> Changed Total number of MSI IRQ count logic according to both architectures.
>> Updated MSI assigning functions accordingly to new count.
>> Modified irq_domain_add_linear with new MSI IRQ count.
>> Added #ifdef to pci_fixup_irqs which is ARM specific API.
>> ---
>>  drivers/pci/host/pcie-xilinx.c | 22 +++++++++++++++++-----
>>  1 file changed, 17 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/pci/host/pcie-xilinx.c b/drivers/pci/host/pcie-xilinx.c
>> index 3e3757f..1981948 100644
>> --- a/drivers/pci/host/pcie-xilinx.c
>> +++ b/drivers/pci/host/pcie-xilinx.c
>> @@ -92,7 +92,12 @@
>>  #define ECAM_DEV_NUM_SHIFT		12
>>  
>>  /* Number of MSI IRQs */
>> -#define XILINX_NUM_MSI_IRQS		128
>> +#define XILINX_NUM_MSI_IRQS	128
>> +#ifdef CONFIG_ARM
>> +#define TOT_NR_IRQS		XILINX_NUM_MSI_IRQS
>> +#else
>> +#define TOT_NR_IRQS		(NR_IRQS + XILINX_NUM_MSI_IRQS)
>> +#endif
> 
> Something looks wrong here in the microblaze variant. What does NR_IRQS
> have to do with it?

Arnd: What was the story regarding NR_IRQS?
I remember some discussion about it but just forget.

Default value in include/asm-generic/irq.h is 64.
Current value is 32 because microblaze primary interrupt controller is
axi_intc core which has up to 32 input lines.

Thanks,
Michal