[PATCH 1/3] Support BE8 mode kernel modules relocation

Catalin Marinas catalin.marinas at arm.com
Mon Jan 17 04:56:50 EST 2011


On 17 January 2011 08:42, Stanley.Miao <stanley.miao at windriver.com> wrote:
> The code section in BE8 kernel modules is in little-endian while data
> section is in big-endian. When reading code from memory in the relocation
> procedure, these instructions are read according to big-endian, so they
> need to be inverted before writing to memory and after reading from memory.
[...]
> --- a/arch/arm/include/asm/io.h
> +++ b/arch/arm/include/asm/io.h
> @@ -233,6 +233,18 @@ extern void _memset_io(volatile void __iomem *, int, size_t);
>
>  #endif /* __mem_pci */
>
> +#ifdef CONFIG_CPU_ENDIAN_BE8
> +#define read_instr32(c)                        __swab32(*(u32 *)c)
> +#define read_instr16(c)                        __swab16(*(u16 *)c)
> +#define write_instr32(v,a)             (*(u32 *)(a) = __swab32((__force __u32)(v)))
> +#define write_instr16(v,a)             (*(u16 *)(a) = __swab16((__force __u16)(v)))
> +#else
> +#define read_instr32(c)                        (*(u32 *)c)
> +#define read_instr16(c)                        (*(u16 *)c)
> +#define write_instr32(v,a)             (*(u32 *)(a) = (v))
> +#define write_instr16(v,a)             (*(u16 *)(a) = (v))
> +#endif

Can we not use cpu_to_le32 etc in here (and as Russell said, they are
not really IO)?

-- 
Catalin



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