[U-Boot] [PATCH 2/9] ARM: cache-cp15: Use unsigned long for address and size

[Stephen Warren]

On 08/18/2014 02:00 AM, Thierry Reding wrote:
> From: Thierry Reding <treding at nvidia.com>
>
> size is always non-negative, so it should be unsigned, whereas the
> address and size can be larger than 32 bit on 64-bit architectures.
> Change the mmu_set_region_dcache_behaviour() to use these types in
> anticipation of making the API available on other architectures.

> diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h

> -void mmu_set_region_dcache_behaviour(u32 start, int size,
> +void mmu_set_region_dcache_behaviour(unsigned long start, unsigned long size,
>   				     enum dcache_option option);

If we were to use LPAE on a 32-bit system, physical addresses could be 
more than 32-bit. That would imply we should create a physaddr_t type 
rather than relying on unsigned long. Still, I suppose since U-Boot just 
maps RAM (and everything else) 1:1, we'd never use RAM beyond 4GiB, so 
LPAE actually isn't that interesting...