Re: [PATCH net] macmace: Set platform device coherent_dma_mask

[Geert Uytterhoeven]

Hi Finn,

On Thu, May 3, 2018 at 6:23 AM, Finn Thain <fthain@xxxxxxxxxxxxxxxxxxx> wrote:
> Set the device's coherent_dma_mask to avoid a WARNING splat.
> Please see commit 205e1b7f51e4 ("dma-mapping: warn when there is
> no coherent_dma_mask").
>
> Cc: linux-m68k@xxxxxxxxxxxxxxxxxxxx
> Tested-by: Stan Johnson <userm57@xxxxxxxxx>
> Signed-off-by: Finn Thain <fthain@xxxxxxxxxxxxxxxxxxx>

Thanks for your patch!

> --- a/drivers/net/ethernet/apple/macmace.c
> +++ b/drivers/net/ethernet/apple/macmace.c
> @@ -203,6 +203,10 @@ static int mace_probe(struct platform_device *pdev)
>         unsigned char checksum = 0;
>         int err;
>
> +       err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
> +       if (err)
> +               return err;
> +
>         dev = alloc_etherdev(PRIV_BYTES);
>         if (!dev)
>                 return -ENOMEM;

Shouldn't this be handled in the platform code that instantiates the device,
i.e. in arch/m68k/mac/config.c:mac_platform_init()?

Cfr. commit f61e64310b75733d ("m68k: set dma and coherent masks for platform
FEC ethernets").

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds