Re: [PATCH] PCI MMConfig: Only map what's necessary.

[Muli Ben-Yehuda <muli@il.ibm.com>]

On Thu, Dec 07, 2006 at 03:50:52PM +0100, Olivier Galibert wrote:
> The x86-64 mmconfig code always map a range of MMCONFIG_APER_MAX
> bytes, i.e. 256MB, whatever the number of accessible busses is.  Fix
> it, and add the end of the zone in the printk while we're at it.
> 
> Signed-off-by: Olivier Galibert <galibert@pobox.com>
> ---
>  arch/x86_64/pci/mmconfig.c |    9 +++------
>  1 files changed, 3 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/x86_64/pci/mmconfig.c b/arch/x86_64/pci/mmconfig.c
> index b270f20..091f759 100644
> --- a/arch/x86_64/pci/mmconfig.c
> +++ b/arch/x86_64/pci/mmconfig.c
> @@ -13,10 +13,6 @@
>  
>  #include "pci.h"
>  
> -/* aperture is up to 256MB but BIOS may reserve less */
> -#define MMCONFIG_APER_MIN	(2 * 1024*1024)
> -#define MMCONFIG_APER_MAX	(256 * 1024*1024)
> -
>  /* Verify the first 16 busses. We assume that systems with more busses
>     get MCFG right. */
>  #define MAX_CHECK_BUS 16
> @@ -145,16 +141,17 @@ int __init pci_mmcfg_arch_init(void)
>  	}
>  
>  	for (i = 0; i < pci_mmcfg_config_num; ++i) {
> +		u32 size = (pci_mmcfg_config[0].end_bus_number - pci_mmcfg_config[0].start_bus_number + 1) << 20;
>  		pci_mmcfg_virt[i].cfg = &pci_mmcfg_config[i];
>  		pci_mmcfg_virt[i].virt = ioremap_nocache(pci_mmcfg_config[i].base_address,
> -							 MMCONFIG_APER_MAX);
> +							 size);
>  		if (!pci_mmcfg_virt[i].virt) {
>  			printk(KERN_ERR "PCI: Cannot map mmconfig aperture for "
>  					"segment %d\n",
>  			       pci_mmcfg_config[i].pci_segment_group_number);
>  			return 0;
>  		}
> -		printk(KERN_INFO "PCI: Using MMCONFIG at %x\n", pci_mmcfg_config[i].base_address);
> +		printk(KERN_INFO "PCI: Using MMCONFIG at %x-%x\n", pci_mmcfg_config[i].base_address, pci_mmcfg_config[i].base_address + size - 1);

80 chars per line please...

Cheers,
Muli