[PATCH 4/4] ARM: keystone: Use dma-ranges for dma_pfn_offset configuration

Arnd Bergmann arnd at arndb.de
Mon Feb 24 16:11:58 EST 2014


On Monday 24 February 2014 15:53:55 Santosh Shilimkar wrote:
> From: Grygorii Strashko <grygorii.strashko at ti.com>
>  }
>  
> +static unsigned long get_dma_pfn_offset(struct device *dev)
> +{
> +	struct device_node *node = of_node_get(dev->of_node);
> +	const u32 *ranges = NULL;
> +	int len, naddr, nsize, pna;
> +	dma_addr_t dma_addr;
> +	phys_addr_t cpu_addr, size;
> +	unsigned long dma_pfn_offset = 0;
> +
> +	if (!node)
> +		return 0;

Hmm, isn't this function the same as of_translate_dma_address()?

I think we should have the implementation in common code, not hidden
in the keystone platform, to avoid duplication. If of_translate_dma_address
doesn't work, what is the problem, and can you fix it there?

>  static int keystone_platform_notifier(struct notifier_block *nb,
>  				      unsigned long event, void *dev)
>  {
> +	struct device *_dev = dev;
> +
>  	if (event != BUS_NOTIFY_ADD_DEVICE)
>  		return NOTIFY_DONE;

Style: it would be nicer to name the local variable 'dev' and the
argument something else like 'p' or 'data'.

I also wonder if this shouldn't be in ARM architecture wide code
rather than platform code. Unfortunately it can't be in drivers/base
since the offset is stored in an ARM specific location.

	Arnd



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