Re: [PATCH 2/3] mtd: spi-nor: intel-spi: Convert to SPI MEM

[Pratyush Yadav <p.yadav@xxxxxx>]

On 08/10/21 12:02PM, Mika Westerberg wrote:
> Hi,
> 
> On Thu, Oct 07, 2021 at 11:30:31PM +0530, Pratyush Yadav wrote:
> > > Probably but I would not call these "problems" - it is how the
> > > controller is designed. This one is meant only for SPI-NOR flash access,
> > > typically used by the BIOS. It is by no means general purpose SPI
> > > controller (as you can see from the datasheet). The BIOS does need the
> > > full SPI stack, it just issues these simple commands and let's the
> > > controller figure out what actually needs to be done.
> > 
> > The problem is not the controller itself. It is perfectly fine piece to 
> > have a controller like this IMO. The problem is how do we make it fit 
> > into the SPI MEM model, which seems to be designed for general purpose 
> > controllers only. This problem is shared with this and the Cadence xSPI 
> > controller.
> 
> Fully agree. IMHO trying to shoehorn driver like this into a generic SPI
> subsystem does not make much sense to me. These things can only talk to
> SPI-NOR chips, nothing else.
> 
> Do you have any suggestions how to solve this "problem" so we can move
> forward with the drivers?

No, I unfortunately don't. But I suppose the same problem existed with 
the old driver as well. It ignored nor->read_opcode, etc. and did its 
own thing, so at least I don't expect things to get much worse with the 
SPI MEM model.

-- 
Regards,
Pratyush Yadav
Texas Instruments Inc.