[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-ppc] [PATCH] spapr-pci: remove io ports workaround
From: |
Alexander Graf |
Subject: |
Re: [Qemu-ppc] [PATCH] spapr-pci: remove io ports workaround |
Date: |
Tue, 16 Jul 2013 10:41:17 +0200 |
Am 16.07.2013 um 10:37 schrieb Alexey Kardashevskiy <address@hidden>:
> On 07/16/2013 06:32 PM, Alexander Graf wrote:
>>
>>
>> Am 16.07.2013 um 08:20 schrieb Paolo Bonzini <address@hidden>:
>>
>>> Il 16/07/2013 07:19, Alexey Kardashevskiy ha scritto:
>>>> In the past, IO space could not be mapped into the memory address space
>>>> so we introduced a workaround for that. Nowadays it does not look
>>>> necessary so we can remove the workaround and make sPAPR PCI
>>>> configuration simplier.
>>>>
>>>> This also removes all byte swappings as it is not PHB's to take care
>>>> of endiannes - devices should do convertion if they want to. And almost
>>>> every PCI device which uses IO ports does that by registering IO ports
>>>> region with memory_region_init_io() (Intel e1000, RTL8139, virtio).
>>>>
>>>> However VGA uses MemoryRegionPortio which does not support endiannes
>>>> but it still expects the convertion to be done. For this case only,
>>>> this patch adds LITTLE_ENDIAN flag to portio_ops. Tests on PPC64 show
>>>> that other devices are not affected by this change. x86 systems should
>>>> not suffer either as having LITTLE_ENDIAN there has no effect.
>>>>
>>>> Signed-off-by: Alexey Kardashevskiy <address@hidden>
>>>> ---
>>>>
>>>> This removes bugs at least from SPAPR so any further fixes should be equal
>>>> for all platforms and hopefully will break all platform altogether but not
>>>> just PPC64-pSeries :)
>>>>
>>>> Did I miss anything here?
>>>
>>> No, I don't think so. The patch looks good.
>>
>> ... and will break all Mac targets again, no? Not to speak of non-ppc
>> devices.
>
>
> Like what? I do not mind/argue/discuss, may be it breaks, I am just looking
> for good examples to test.
How about you start with
$ qemu-system-ppc
Then? It shouldn't show a prompt with your patch ;)
Alex
>
>
>
> --
> Alexey
- [Qemu-ppc] [PATCH] spapr-pci: remove io ports workaround, Alexey Kardashevskiy, 2013/07/14
- Re: [Qemu-ppc] [PATCH] spapr-pci: remove io ports workaround, Alexander Graf, 2013/07/15
- Re: [Qemu-ppc] [PATCH] spapr-pci: remove io ports workaround, Alexey Kardashevskiy, 2013/07/15
- [Qemu-ppc] [PATCH] spapr-pci: remove io ports workaround, Alexey Kardashevskiy, 2013/07/16
- Re: [Qemu-ppc] [PATCH] spapr-pci: remove io ports workaround, Benjamin Herrenschmidt, 2013/07/16
- Re: [Qemu-ppc] [PATCH] spapr-pci: remove io ports workaround, Alexander Graf, 2013/07/16
- Re: [Qemu-ppc] [PATCH] spapr-pci: remove io ports workaround, Alexey Kardashevskiy, 2013/07/16