Re: [PATCH] adjust legacy IDE resource setting (v2)

[Alan Cox <alan@redhat.com>]

On Thu, Feb 15, 2007 at 08:02:21AM +0000, Jan Beulich wrote:
> The change to force legacy mode IDE channels' resources to fixed
> non-zero values confuses (at least some versions of) X, because the
> values reported by the kernel and those readable from PCI config space
> aren't consistent anymore. Therefore, this patch arranges for the
> respective BARs to also get updated if possible.
> 
> (The only change to the original version is an added comment.)
> 
> Signed-off-by: Jan Beulich <jbeulich@novell.com>

Acked-by: Alan Cox <alan@redhat.com>

> 
> --- linux-2.6.20/drivers/pci/probe.c	2007-02-04 19:44:54.000000000 +0100
> +++ 2.6.20-pci-ide-legacy/drivers/pci/probe.c	2007-02-15 08:54:58.000000000 +0100
> @@ -639,7 +639,34 @@ static void pci_read_irq(struct pci_dev 
>  	dev->irq = irq;
>  }
>  
> -#define LEGACY_IO_RESOURCE	(IORESOURCE_IO | IORESOURCE_PCI_FIXED)
> +static void change_legacy_io_resource(struct pci_dev * dev, unsigned index,
> +                                      unsigned start, unsigned end)
> +{
> +	unsigned base = start & PCI_BASE_ADDRESS_IO_MASK;
> +	unsigned len = (end | ~PCI_BASE_ADDRESS_IO_MASK) - base + 1;
> +
> +	/*
> +	 * Some X versions get confused when the BARs reported through
> +	 * /sys or /proc differ from those seen in config space, thus
> +	 * try to update the config space values, too.
> +	 */
> +	if (!(pci_resource_flags(dev, index) & IORESOURCE_IO))
> +		printk(KERN_WARNING "%s: cannot adjust BAR%u (not I/O)\n",
> +		       pci_name(dev), index);
> +	else if (pci_resource_len(dev, index) != len)
> +		printk(KERN_WARNING "%s: cannot adjust BAR%u (size %04X)\n",
> +		       pci_name(dev), index, (unsigned)pci_resource_len(dev, index));
> +	else {
> +		printk(KERN_INFO "%s: trying to change BAR%u from %04X to %04X\n",
> +		       pci_name(dev), index,
> +		       (unsigned)pci_resource_start(dev, index), base);
> +		pci_write_config_dword(dev, PCI_BASE_ADDRESS_0 + index * 4, base);
> +	}
> +	pci_resource_start(dev, index) = start;
> +	pci_resource_end(dev, index)   = end;
> +	pci_resource_flags(dev, index) =
> +		IORESOURCE_IO | IORESOURCE_PCI_FIXED | PCI_BASE_ADDRESS_SPACE_IO;
> +}
>  
>  /**
>   * pci_setup_device - fill in class and map information of a device
> @@ -692,20 +719,12 @@ static int pci_setup_device(struct pci_d
>  			u8 progif;
>  			pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
>  			if ((progif & 1) == 0) {
> -				dev->resource[0].start = 0x1F0;
> -				dev->resource[0].end = 0x1F7;
> -				dev->resource[0].flags = LEGACY_IO_RESOURCE;
> -				dev->resource[1].start = 0x3F6;
> -				dev->resource[1].end = 0x3F6;
> -				dev->resource[1].flags = LEGACY_IO_RESOURCE;
> +				change_legacy_io_resource(dev, 0, 0x1F0, 0x1F7);
> +				change_legacy_io_resource(dev, 1, 0x3F6, 0x3F6);
>  			}
>  			if ((progif & 4) == 0) {
> -				dev->resource[2].start = 0x170;
> -				dev->resource[2].end = 0x177;
> -				dev->resource[2].flags = LEGACY_IO_RESOURCE;
> -				dev->resource[3].start = 0x376;
> -				dev->resource[3].end = 0x376;
> -				dev->resource[3].flags = LEGACY_IO_RESOURCE;
> +				change_legacy_io_resource(dev, 2, 0x170, 0x177);
> +				change_legacy_io_resource(dev, 3, 0x376, 0x376);
>  			}
>  		}
>  		break;
> 

-- 
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