IXP4xx: unneeded #include platform-specific include files?

[Imre Kaloz]

On 2009.11.17. 22:53:38 Krzysztof Halasa <khc at pm.waw.pl> wrote:

> "Imre Kaloz" <kaloz at openwrt.org> writes:
>
>> Ok, I should be completely missing the point here, but could someone enlighten
>> me why would the following make sense? (nslu2 example)
>>
>> #define NSLU2_PCI_INTA_PIN	11
>> #define NSLU2_PCI_INTB_PIN	10
>> #define NSLU2_PCI_INTC_PIN	9
>> #define NSLU2_PCI_INTD_PIN	8
>>
>> #define        IRQ_NSLU2_PCI_INTA      IRQ_IXP4XX_GPIO11
>> #define        IRQ_NSLU2_PCI_INTB      IRQ_IXP4XX_GPIO10
>> #define        IRQ_NSLU2_PCI_INTC      IRQ_IXP4XX_GPIO9
>
> Well, this isn't something I really like because it duplicates the
> assignments.
>
>> Then do all the "fun" in the setup code, instead of simply using
>> The already defined (and hardware wise more logical) IRQ_IXP4XX_GPIOx values like
>> I do in arch/arch/mach-ixp4xx/wg302v2-pci.c for example?
>
> void __init wg302v2_pci_preinit(void)
> {
>         set_irq_type(IRQ_IXP4XX_GPIO8, IRQ_TYPE_LEVEL_LOW);
>         set_irq_type(IRQ_IXP4XX_GPIO9, IRQ_TYPE_LEVEL_LOW);
>
>         ixp4xx_pci_preinit();
> }
>
> static int __init wg302v2_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
> {
>         if (slot == 1)
>                 return IRQ_IXP4XX_GPIO8;
>         else if (slot == 2)
>                 return IRQ_IXP4XX_GPIO9;
>         else return -1;
> }
>
> Not very different from what other platforms have, except that you have
> to remember the assignment. When the code gets more complicated you
> really don't want to remember that INTA is GPIO8, INTB is GPIO9, INTC,
> INTD, IDE_IRQ, USB_IRQ etc. And this gets even more complicated when the
> platform code supports more than one version of hw.

Why wouldn't you want to remember that "INTA" was "GPIO8"? When you want to
touch those lines you do have to remember or look up what GPIO was that one.
So this hardly makes it easier to work with or to remember to -- it certainly
duplicates the assignments, as you've also noted.

The INTx naming convention is also stupid, as in most cases these are not different
INT lines of the PCI slot but either separate slots or subdevices -- and note,
most of the boards only have INTa connected mechanically.

And I didn't even get to the topic of *_PCI_MAX_DEV, *_PCI_IRQ_LINES and the mania
of pci_irq_table usage..


Imre