[SLOF] [PATCH slof] pci: Put non-prefetchable 64bit BARs into 32bit MMIO window
Laurent Vivier
lvivier at redhat.com
Tue Apr 25 20:36:44 AEST 2017
On 24/04/2017 05:01, Alexey Kardashevskiy wrote:
> At the moment 64bit non-prefetchable BARs of devices behind PCI p2p
> bridge go to a 64bit prefetchable windows which is not correct and
> causes linux guests to fail to ioremap() such resources.
>
> This moves 64bit non-prefetchable BARs 32bit non-prefetchable window.
>
> Note that this does not make distinction between P2P and PHB so
> from now on XHCI BARs will be allocated from 32bit MMIO space.
> However since most 64bit-MMIO-capable devices have prefetchable BARs,
> and XHCI BAR is just 4K (so it is unlikely to cause any space problems),
> this should not affect usual behavior.
>
> Signed-off-by: Alexey Kardashevskiy <aik at ozlabs.ru>
> ---
>
> This fixes QEMU's XHCI when it is put on a P2P PCI bridge.
>
> There is a little naming confusion as it may look like the patch
> is changing assignment for all 64bit BAR but it does not as:
> - "mmio" is used for non-prefetchable memory,
> - "mem" is used for prefetchable memory.
> ---
> slof/fs/pci-properties.fs | 6 +-----
> 1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/slof/fs/pci-properties.fs b/slof/fs/pci-properties.fs
> index e6fd843..8594e5d 100644
> --- a/slof/fs/pci-properties.fs
> +++ b/slof/fs/pci-properties.fs
> @@ -166,11 +166,7 @@
> \ Setup a non-prefetchable 64bit BAR and return its size
> : assign-mmio64-bar ( bar-addr -- 8 )
> dup pci-bar-size-mem64 \ fetch size
> - pci-next-mem64 @ 0 = IF \ Check if we have 64-bit memory range
> - pci-next-mmio
> - ELSE
> - pci-next-mem64 \ for board-qemu we will use same range
> - THEN
> + pci-next-mmio
> assign-bar-value64 \ and set it all
> ;
>
>
Tested-by: Laurent Vivier <lvivier at redhat.com>
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