Re: [RFC PATCH v1 0/2] scsi: ufs: introduce vendor isr

From: Bart Van Assche
Date: Mon Aug 09 2021 - 12:09:02 EST


On 8/9/21 12:46 AM, Kiwoong Kim wrote:
>> How about extending the UFS spec instead of adding a non-standard
>> mechanism in a driver that is otherwise based on a standard?
>
> It seems to be a great approach but I wonder if extending for the events
> that all the SoC vendors require in the spec is recommendable.
> Because I think there is quite possible that many of those things are
> originated for architectural reasons.

Has the interrupt mechanism supported by this patch series already been
implemented or is it still possible to change the ASIC design? In the
latter case, I propose the following:
* Drop the new interrupt.
* Instead of raising an interrupt if the UFS controller detects an
inconsistency, report this via a check condition code, e.g. LOGICAL UNIT
NOT READY, HARD RESET REQUIRED (there may be a better choice).

The above approach has the advantage that it does not slow down the UFS
interrupt handler.

Thanks,

Bart.