On 05/22/2018 11:52 AM, Marek Vasut wrote:
> On 05/22/2018 10:10 AM, Arnd Bergmann wrote:
>> On Tue, May 22, 2018 at 12:05 AM, Marek Vasut <[email protected]> wrote:
>>> From: Phil Edworthy <[email protected]>
>>>
>>> The PCIe DMA controller on RCar Gen2 and earlier is on 32bit bus,
>>> so limit the DMA range to 32bit.
>>>
>>> Signed-off-by: Phil Edworthy <[email protected]>
>>> Signed-off-by: Marek Vasut <[email protected]>
>>> Cc: Arnd Bergmann <[email protected]>
>>> Cc: Geert Uytterhoeven <[email protected]>
>>> Cc: Phil Edworthy <[email protected]>
>>> Cc: Simon Horman <[email protected]>
>>> Cc: Wolfram Sang <[email protected]>
>>> Cc: [email protected]
>>> To: [email protected]
>>> ---
>>> NOTE: I'm aware of https://patchwork.kernel.org/patch/9495895/ , but the
>>>       discussion seems to have gone way off, so I'm sending this as a
>>>       RFC. Any feedback on how to do this limiting properly would be nice.
>>
>> Doing it in the driver is clearly not appropriate, we must do this in
>> common code. If I remember correctly, it's specifically ARM64 that is
>> broken here, it incorrectly allows setting a DMA mask to 64 bit
>> when that is not available.
> 
> Yep, that's correct. ARM64 with devices mapping tremendous amounts of
> memory. So did anything change since that discussion references in the NOTE?

Bump ? I think it'd be nice to sort this out once and for all, since I
doubt it's just this controller that has such a limitation.

-- 
Best regards,
Marek Vasut

Reply via email to