Re: [PATCH v2] i2c: designware: Fix corrupted memory seen in the ISR

Jan Bottorff
2023-11-01T16:52:18Z

On 10/31/2023 6:06 AM, Serge Semin wrote:
> On Tue, Oct 31, 2023 at 02:10:13PM +0200, Jarkko Nikula wrote:
>> On 10/31/23 10:44, Yann Sionneau wrote:
>>>
>>> Le 31/10/2023 à 01:12, Jan Bottorff a écrit :
>>>> On 10/26/2023 4:18 AM, Wolfram Sang wrote:
>>>>> So, someone wants to come up with a patch to move to non-relaxed io
>>>>> accessors?
>>>>>
...
>>>> I could make the patch if we have consensus (or maintainers
>>>> decision) on which way to go: 1) only writes to DW_IC_INTR_MASK are
>>>> non-relaxed, 2) make all read/write accessors use the non-relaxed
>>>> version.
>>>
>>> Fine with me, let's go for #2 :)
>>>
>> Also simplicity votes for #2.
>
> +1 for the option #2. Let's do it and be finally over with this
> patch.)
>
> -Serge(y)

I think we have agreement to make the dw i2c driver regmap accessors use
the non-relaxed low-level functions, like writel instead of
writel_relaxed. These low level functions have memory barriers on
platforms that require them.

I'll work on a patch for this.

- Jan