Re: [PATCH] serial: 8250_lpss: Unconditionally set PCI master for Quark

From: Jan Kiszka
Date: Tue Jan 10 2017 - 01:54:46 EST


On 2017-01-10 00:24, Andy Shevchenko wrote:
> On Mon, Jan 9, 2017 at 7:11 PM, Jan Kiszka <jan.kiszka@xxxxxxxxxxx> wrote:
>> On 2017-01-05 22:56, Andy Shevchenko wrote:
>>> On Thu, Jan 5, 2017 at 1:56 AM, Andy Shevchenko
>>> <andy.shevchenko@xxxxxxxxx> wrote:
>>>
>>> Ah, Jan, perhaps you would like to comment on this one as well
>>> http://marc.info/?l=linux-serial&m=148334902916347&w=2
>>> ?
>>>
>>
>> http://marc.info/?l=linux-serial&m=148334905916354&w=2 enables MSI, but
>> that's only for Denverton, and there it is unconditional. So this is ok.
>
> I think there is potential issue, if DMA driver is not compiled or
> probed (by whatever reason) we will have MSI enabled without bus
> mastering.
> And like you said for sake of not copying wrong pattern for new API,
> would be good to move it.

Ah, indeed: the pci_set_master is not yet done unconditionally. Move it
prior to hsu_dma_probe, and everyone should be happy.

Jan

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