[PATCH linux dev-4.7 09/12] mtd: spi-nor: aspeed: add DMA support to smc controller

[Joel Stanley]

On Fri, Oct 14, 2016 at 11:08 PM, Cédric Le Goater <clg at kaod.org> wrote:
> The Aspeed FMC controller can handle transfers to the flash modules
> using DMAs. A couple of registers first need to be programmed with the
> DRAM and flash addresses and the length of the transfer. The transfer
> is then initiated using a DMA control register and an interrupt
> notifies the completion.
>
> Such transfers can replace the current IO mode in the read/write ops
> when some conditions are met on the size and the alignment. In case of
> failure, a timeout for instance, the operation is restarted using the
> IO mode.
>
> DMA support does not seem to be that efficient. So we provide some
> sysfs files for tuning and to switch it on and off (default is off)

It looks like this version only has a module parameter, and not the sysfs files.

>
> Signed-off-by: Cédric Le Goater <clg at kaod.org>

Reviewed-by: Joel Stanley <joel at jms.id.au>

> ---
>  drivers/mtd/spi-nor/aspeed-smc.c | 246 ++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 243 insertions(+), 3 deletions(-)
>

>         /*
> @@ -530,6 +769,7 @@ static int aspeed_smc_probe(struct platform_device *pdev)
>                         continue;
>                 }
>
> +               chip->phys_base = r->start;
>                 /*
>                  * Always turn on the write enable bit in the type and settings
>                  * or flash configuration register to allow opcodes to be sent
> @@ -621,7 +861,7 @@ static struct platform_driver aspeed_smc_driver = {
>         .probe = aspeed_smc_probe,
>         .remove = aspeed_smc_remove,
>         .driver = {
> -               .name = KBUILD_MODNAME,
> +               .name = DEVICE_NAME,

This should be in a different commit.

>                 .of_match_table = aspeed_smc_matches,
>         }
>  };
> --
> 2.7.4
>