[parisc-linux] Re: [PATCH] PCMCIA: Disable probing on parisc

[Grant Grundler]

On Sun, Dec 11, 2005 at 11:35:02PM +0100, Helge Deller wrote:
> Grant helped me to analyze this problem.
> The pcmcia irq line seems to be allways off-by-one, e.g. PCI irq 25
> got local irq 2 on dino which was wrong and should have become "1".
> Grants comment on this was:
>  "Sounds like we need a quirk in drivers/pci/quirks.c to deal with this."

Before I propose the quirk to linux-pci, I need to know the scope of the
problem. Is this a problem only for that PCI slot on that box, for any
slot under dino, any PARISC PCI, or any PCI platform?

For starters, can someone test this on same card on a C3000 or A500?
Both of those use a routing table instead of magic values in PCI device
config registers.

# lspci -vs 00:02.0
0000:00:02.0 CardBus bridge: Cirrus Logic PD 6832 PCMCIA/CardBus Ctrlr (rev c1)
	Flags: bus master, medium devsel, latency 168, IRQ 25
	Memory at f0800000 (32-bit, non-prefetchable) [size=4K]
	Bus: primary=00, secondary=01, subordinate=04, sec-latency=176
	Memory window 0: f0c00000-f0fff000
	Memory window 1: f0900000-f09ff000
	I/O window 0: 00000400-000005ff
	I/O window 1: 00000800-000009ff
	16-bit legacy interface ports at 0001

>  "or our algorithm for routing IRQ_PIN to INTERRUPT_LINE routing is broken."

Right now, I can't convinced myself this is a PDC bug on platforms
with built-in Dino.  PDC fills in PCI_INTERRUPT_LINE (becomes pci_dev->irq)
value with the DINO input Interrupt Line (ie index into dino->global_irq[]).
This is used by dino code instead of a "Routing Table".

Other parisc boxes and most architectures use some form of
"IRQ Line Routing Table" to communicate PCI device IRQ_PIN output
to Interrupt Controller input lines mappings to the OS.

But other PCI LAN and SCSI cards work fine under built-in Dino AFAIK.
That's why I'm not sure about the scope of the problem.

> Based on that I just created the attached patch.
> With it pcmcia now works for me.

Yeah, the patch looks fine to me.
I'd just like confirmation that C3000 has the same problem before
I forget how all this works again.

If it doesn't, then we need to figure out how to make this
a dino specific "quirk".

> Maybe you have an idea if something in dino is wrong ?

I don't think there is anything wrong with dino.
Otherwise other cards wouldn't work right either.

thanks,
grant

> 
> Helge
> 
> dmesg:
> PCI: Cirrus Cardbus IRQ fixup for 0000:00:02.0, from 25 to 24 (old native irq=2)
> Yenta: CardBus bridge found at 0000:00:02.0 [0000:0000]
> PCI: Bus 1, cardbus bridge: 0000:00:02.0
>   IO window: 00000400-000005ff
>   IO window: 00000800-000009ff
>   PREFETCH window: f0c00000-f0ffffff
>   MEM window: f0900000-f09fffff
> Yenta: ISA IRQ mask 0x0000, PCI irq 24
> Socket status: 30000007
> pcmcia: parent PCI bridge I/O window: 0x0 - 0xffff
> pcmcia: parent PCI bridge Memory window: 0xf0800000 - 0xf0ffffff
> PCI: Cirrus Cardbus IRQ fixup for 0000:00:02.1, from 26 to 25 (old native irq=3)
> Yenta: CardBus bridge found at 0000:00:02.1 [0000:0000]
> PCI: Bus 5, cardbus bridge: 0000:00:02.1
>   IO window: 00000c00-00000dff
>   IO window: 00001000-000011ff
>   PREFETCH window: f0a00000-f0afffff
>   MEM window: f0b00000-f0bfffff
> Yenta: ISA IRQ mask 0x0000, PCI irq 25
> Socket status: 30000007
> pcmcia: parent PCI bridge I/O window: 0x0 - 0xffff
> pcmcia: parent PCI bridge Memory window: 0xf0800000 - 0xf0ffffff
> ds: ds_open(socket 0)

> Index: quirks.c
> ===================================================================
> RCS file: /var/cvs/linux-2.6/drivers/pci/quirks.c,v
> retrieving revision 1.35
> diff -u -p -r1.35 quirks.c
> --- quirks.c	12 Nov 2005 04:08:03 -0000	1.35
> +++ quirks.c	11 Dec 2005 22:22:58 -0000
> @@ -862,6 +862,28 @@ static void __init quirk_eisa_bridge(str
>  DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL,	PCI_DEVICE_ID_INTEL_82375,	quirk_eisa_bridge );
>  
>  /*
> + * Cirrus 6832 Cardbus reports wrong irq on RDI Tadpole PARISC Laptop.
> + */
> +#if defined(CONFIG_PARISC)
> +static void __devinit quirk_hp_cardbus(struct pci_dev *dev)
> +{
> +        u8 irq, new_irq;
> +
> +	new_irq = dev->irq - 1;
> +        pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
> +
> +	printk(KERN_ERR "PCI: Cirrus Cardbus IRQ fixup for %s, from %d to %d (old native irq=%d)\n",
> +                        pci_name(dev), dev->irq, new_irq, irq);
> +	dev->irq = new_irq;
> +
> +	udelay(15);     /* unknown if delay really needed */
> +	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, new_irq);
> +
> +}
> +DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_CIRRUS,	PCI_DEVICE_ID_CIRRUS_6832,	quirk_hp_cardbus );
> +#endif
> +
> +/*
>   * On ASUS P4B boards, the SMBus PCI Device within the ICH2/4 southbridge
>   * is not activated. The myth is that Asus said that they do not want the
>   * users to be irritated by just another PCI Device in the Win98 device