Re: [PATCH] PCI: Always set prefetchable base/limit upper32registers

From: Grant Grundler
Date: Mon Nov 30 2009 - 16:42:53 EST


On Mon, Nov 30, 2009 at 02:22:53PM -0700, Alex Williamson wrote:
> Prior to 1f82de10 we always initialized the upper 32bits of the
> prefetchable memory window, regardless of the address range used.
> Now we only touch it for a >32bit address, which means the upper32
> registers remain whatever the BIOS initialized them too.
>
> It's valid for the BIOS to set the upper32 base/limit to
> 0xffffffff/0x00000000, which makes us program prefetchable ranges
> like 0xffffffffabc00000 - 0x00000000abc00000
>
> Revert the chunk of 1f82de10 that made this conditional so we always
> write the upper32 registers.
>
> Signed-off-by: Alex Williamson <alex.williamson@xxxxxx>
> ---
>
> drivers/pci/setup-bus.c | 8 +++-----
> 1 files changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
> index cb1a027..127d759 100644
> --- a/drivers/pci/setup-bus.c
> +++ b/drivers/pci/setup-bus.c
> @@ -221,11 +221,9 @@ static void pci_setup_bridge(struct pci_bus *bus)
> }
> pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, l);
>
> - if (pref_mem64) {
> - /* Set the upper 32 bits of PREF base & limit. */
> - pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, bu);
> - pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, lu);
> - }

Why not remove all references to pref_mem64?
This was the only use AFAICT.

thanks,
grant

> + /* Set the upper 32 bits of PREF base & limit. */
> + pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, bu);
> + pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, lu);
>
> pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, bus->bridge_ctl);
> }
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pci" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/