[RFC/PATCH 3/9] of: dma: Move range size workaround to of_dma_get_range()

[Rob Herring]

On Thu, May 14, 2015 at 6:00 PM, Laurent Pinchart
<laurent.pinchart+renesas at ideasonboard.com> wrote:
> Invalid dma-ranges values should be worked around when retrieving the
> DMA range in of_dma_get_range(), not by all callers of the function.
> This isn't much of a problem now that we have a single caller, but that
> situation will change when moving DMA configuration to device probe
> time.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com>
> ---
>  drivers/of/address.c | 20 ++++++++++++++++++--
>  drivers/of/device.c  | 15 ---------------

Please use get_maintainers.pl. Anyway, looks fine to me:

Acked-by: Rob Herring <robh at kernel.org>

Rob

>  2 files changed, 18 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/of/address.c b/drivers/of/address.c
> index 78a7dcbec7d8..75eebd19ebfa 100644
> --- a/drivers/of/address.c
> +++ b/drivers/of/address.c
> @@ -924,8 +924,8 @@ EXPORT_SYMBOL(of_io_request_and_map);
>   *     CPU addr (phys_addr_t)  : pna cells
>   *     size                    : nsize cells
>   *
> - * It returns -ENODEV if "dma-ranges" property was not found
> - * for this device in DT.
> + * Return 0 on success, -ENODEV if the "dma-ranges" property was not found for
> + * this device in DT, or -EINVAL if the CPU address or size is invalid.
>   */
>  int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size)
>  {
> @@ -986,6 +986,22 @@ int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *siz
>         *dma_addr = dmaaddr;
>
>         *size = of_read_number(ranges + naddr + pna, nsize);
> +       /*
> +        * DT nodes sometimes incorrectly set the size as a mask. Work around
> +        * those incorrect DT by computing the size as mask + 1.
> +        */
> +       if (*size & 1) {
> +               pr_warn("%s: size 0x%llx for dma-range in node(%s) set as mask\n",
> +                       __func__, *size, np->full_name);
> +               *size = *size + 1;
> +       }
> +
> +       if (!*size) {
> +               pr_err("%s: invalid size zero for dma-range in node(%s)\n",
> +                      __func__, np->full_name);
> +               ret = -EINVAL;
> +               goto out;
> +       }
>
>         pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
>                  *dma_addr, *paddr, *size);
> diff --git a/drivers/of/device.c b/drivers/of/device.c
> index 20c1332a0018..530aa1ed3e1b 100644
> --- a/drivers/of/device.c
> +++ b/drivers/of/device.c
> @@ -109,21 +109,6 @@ void of_dma_configure(struct device *dev, struct device_node *np)
>                 size = dev->coherent_dma_mask + 1;
>         } else {
>                 offset = PFN_DOWN(paddr - dma_addr);
> -
> -               /*
> -                * Add a work around to treat the size as mask + 1 in case
> -                * it is defined in DT as a mask.
> -                */
> -               if (size & 1) {
> -                       dev_warn(dev, "Invalid size 0x%llx for dma-range\n",
> -                                size);
> -                       size = size + 1;
> -               }
> -
> -               if (!size) {
> -                       dev_err(dev, "Adjusted size 0x%llx invalid\n", size);
> -                       return;
> -               }
>                 dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
>         }
>
> --
> 2.3.6
>
>
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