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

Will Deacon
2015-05-27T17:59:23Z

On Fri, May 15, 2015 at 12:00:04AM +0100, Laurent Pinchart 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@ideasonboard.com>
> ---
> drivers/of/address.c | 20 ++++++++++++++++++--
> drivers/of/device.c | 15 ---------------
> 2 files changed, 18 insertions(+), 17 deletions(-)

Looks good to me:

Acked-by: Will Deacon <will.deacon@arm.com>

Will

> 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
>