Re: [PATCH 01/02] ARM: shmobile: Add shared R-Car Gen2 CMA reservation code

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Magnus,

On Mon, Jun 9, 2014 at 2:38 PM, Magnus Damm <magnus.damm@gmail.com> wrote:
> --- 0001/arch/arm/mach-shmobile/setup-rcar-gen2.c
> +++ work/arch/arm/mach-shmobile/setup-rcar-gen2.c       2014-06-09 21:01:33.000000000 +0900

> +static int __init rcar_gen2_scan_mem(unsigned long node, const char *uname,
> +                                    int depth, void *data)
> +{

> +       u64 lpae_start = (u64)1 << 32;

Casts are evil:

1ULL << 32

(I hope one day gcc will gain a "-Wcast" option, so we can easily find and
 inspect all casts, as C-style casts are much more difficult to grep for than
 C++-style casts).

> +       /* We are scanning "memory" nodes only */
> +       if (type = NULL) {
> +               /*
> +                * The longtrail doesn't have a device_type on the
> +                * /memory node, so look for the node called /memory@0.
> +                */
> +               if (depth != 1 || strcmp(uname, "memory@0") != 0)
> +                       return 0;

AFAIK Open Firmware in the LongTrail does not support plugging in ARM CPUs
in its PPC 603e/604e-compatible CPU socket ;-)

> +struct cma *rcar_gen2_dma_contiguous;
> +
> +void __init rcar_gen2_reserve(void)
> +{

> +#ifdef CONFIG_DMA_CMA
> +       if (mrc.size)
> +               dma_contiguous_reserve_area(mrc.size, mrc.base, 0,
> +                                           &rcar_gen2_dma_contiguous);
> +#endif

I assume one day rcar_gen2_dma_contiguous will become used?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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