RE: [PATCH v2 2/3] mtd: rawnand: cadence: use dma_map_resource for sdma address

[Rabara, Niravkumar L]

Hi Miquel,

> -----Original Message-----
> From: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
> Sent: Tuesday, 21 January, 2025 5:53 PM
> To: Rabara, Niravkumar L <niravkumar.l.rabara@xxxxxxxxx>
> Cc: Richard Weinberger <richard@xxxxxx>; Vignesh Raghavendra
> <vigneshr@xxxxxx>; linux@xxxxxxxxxxx; Shen Lichuan
> <shenlichuan@xxxxxxxx>; Jinjie Ruan <ruanjinjie@xxxxxxxxxx>; u.kleine-
> koenig@xxxxxxxxxxxx; linux-mtd@xxxxxxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; stable@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH v2 2/3] mtd: rawnand: cadence: use dma_map_resource
> for sdma address
> 
> Hello,
> 
> On 16/01/2025 at 11:21:53 +08, niravkumar.l.rabara@xxxxxxxxx wrote:
> 
> > From: Niravkumar L Rabara <niravkumar.l.rabara@xxxxxxxxx>
> >
> > Map the slave DMA I/O address using dma_map_resource.
> > When ARM SMMU is enabled, using a direct physical address of SDMA
> > results in DMA transaction failure.
> 
> It is in general a better practice anyway. Drivers should be portable and
> always remap resources.
> 

Do you think the commit message below would be better, or 
stick with the existing one?

Remap the slave DMA I/O resources to enhance driver portability.
Using a physical address causes DMA translation failure when the
ARM SMMU is enabled.

Thanks,
Nirav