[PATCH 2.6.15-rc3-mm1] PCI Quirk: 1K I/O Space Granularity on Intel P64H2

[PATCH 2.6.15-rc3-mm1] PCI Quirk: 1K I/O Space Granularity on Intel P64H2

[Yeisley, Dan P.]

I've implemented a quirk to take advantage of the 1KB I/O space
granularity option on the Intel P64H2 PCI Bridge.  I had to change
probe.c because it sets the resource start and end to be aligned on 4k
boundaries (after the quirk sets them to 1k boundaries).  I've tested
this patch on a Unisys ES7000-600 both with and without the 1KB option
enabled.  I also tested this on a 2 processor Dell box that doesn't have
a P64H2 to make sure there were no negative affects there.

Signed-off-by: Dan Yeisley <dan.yeisley@unisys.com>
---


diff -Naur linux-a/drivers/pci/probe.c linux-b/drivers/pci/probe.c
--- linux-a/drivers/pci/probe.c	2005-12-01 01:07:30.000000000 -0800
+++ linux-b/drivers/pci/probe.c	2005-11-30 05:13:41.000000000 -0800
@@ -264,8 +264,10 @@
 
 	if (base <= limit) {
 		res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) |
IORESOURCE_IO;
-		res->start = base;
-		res->end = limit + 0xfff;
+		if(!res->start)
+			res->start = base;
+		if(!res->end)
+			res->end = limit + 0xfff;
 	}
 
 	res = child->resource[1];
diff -Naur linux-a/drivers/pci/quirks.c linux-b/drivers/pci/quirks.c
--- linux-a/drivers/pci/quirks.c	2005-12-01 01:07:30.000000000
-0800
+++ linux-b/drivers/pci/quirks.c	2005-12-01 01:10:41.000000000
-0800
@@ -1312,6 +1312,35 @@
 	pci_do_fixups(dev, start, end);
 }
 
+/*
+** Intel P64H2 PCI Bridge
+** 	Enable 1k I/O space granularity
+*/
+static void __devinit quirk_p64h2_1k_io(struct pci_dev *dev)
+{
+	u16 en1k;
+	u8 io_base_lo, io_limit_lo;
+	unsigned long base, limit;
+	struct resource *res = dev->resource + PCI_BRIDGE_RESOURCES;
+
+	pci_read_config_word(dev, 0x40, &en1k);
+
+	if(en1k & 0x200) {
+		printk(KERN_INFO "PCI: Enable I/O Space to 1 KB
Granularity\n");
+
+		pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
+		pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
+		base = (io_base_lo & (PCI_IO_RANGE_MASK | 0x0c)) << 8;
+		limit = (io_limit_lo & (PCI_IO_RANGE_MASK | 0x0c)) << 8;
+
+		if(base <= limit) {
+			res->start = base;
+			res->end = limit + 0x3ff;
+		}
+	}
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL,	0x1460,
quirk_p64h2_1k_io);
+
 EXPORT_SYMBOL_GPL(pcie_mch_quirk);
 #ifdef CONFIG_HOTPLUG
 EXPORT_SYMBOL_GPL(pci_fixup_device);

Re: [PATCH 2.6.15-rc3-mm1] PCI Quirk: 1K I/O Space Granularity on Intel P64H2

[Greg KH]

On Thu, Dec 01, 2005 at 02:37:03PM -0500, Yeisley, Dan P. wrote:
> I've implemented a quirk to take advantage of the 1KB I/O space
> granularity option on the Intel P64H2 PCI Bridge.  I had to change
> probe.c because it sets the resource start and end to be aligned on 4k
> boundaries (after the quirk sets them to 1k boundaries).  I've tested
> this patch on a Unisys ES7000-600 both with and without the 1KB option
> enabled.  I also tested this on a 2 processor Dell box that doesn't have
> a P64H2 to make sure there were no negative affects there.
> 
> Signed-off-by: Dan Yeisley <dan.yeisley@unisys.com>
> ---
> 
> 
> diff -Naur linux-a/drivers/pci/probe.c linux-b/drivers/pci/probe.c
> --- linux-a/drivers/pci/probe.c	2005-12-01 01:07:30.000000000 -0800
> +++ linux-b/drivers/pci/probe.c	2005-11-30 05:13:41.000000000 -0800
> @@ -264,8 +264,10 @@
>  
>  	if (base <= limit) {
>  		res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) |
> IORESOURCE_IO;

Your patch is linewrapped and can not be applied :(

Care to try again?

> -		res->start = base;
> -		res->end = limit + 0xfff;
> +		if(!res->start)
> +			res->start = base;
> +		if(!res->end)
> +			res->end = limit + 0xfff;

Why is this necessary, if your quirk already sets these values?

>  	}
>  
>  	res = child->resource[1];
> diff -Naur linux-a/drivers/pci/quirks.c linux-b/drivers/pci/quirks.c
> --- linux-a/drivers/pci/quirks.c	2005-12-01 01:07:30.000000000
> -0800
> +++ linux-b/drivers/pci/quirks.c	2005-12-01 01:10:41.000000000
> -0800
> @@ -1312,6 +1312,35 @@
>  	pci_do_fixups(dev, start, end);
>  }
>  
> +/*
> +** Intel P64H2 PCI Bridge
> +** 	Enable 1k I/O space granularity
> +*/

That's a very odd function comment format.  Care to use the standard
kernel format instead?

> +static void __devinit quirk_p64h2_1k_io(struct pci_dev *dev)
> +{
> +	u16 en1k;
> +	u8 io_base_lo, io_limit_lo;
> +	unsigned long base, limit;
> +	struct resource *res = dev->resource + PCI_BRIDGE_RESOURCES;
> +
> +	pci_read_config_word(dev, 0x40, &en1k);
> +
> +	if(en1k & 0x200) {

Space after "if" and before "(" please.

> +		printk(KERN_INFO "PCI: Enable I/O Space to 1 KB
> Granularity\n");
> +
> +		pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
> +		pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
> +		base = (io_base_lo & (PCI_IO_RANGE_MASK | 0x0c)) << 8;
> +		limit = (io_limit_lo & (PCI_IO_RANGE_MASK | 0x0c)) << 8;
> +
> +		if(base <= limit) {

Space after "if" and before "(" please.

thanks,

greg k-h