Re: [PATCH v2 03/11] goldfish_rtc: Add endianness property

[Richard Henderson <richard.henderson@linaro.org>]

On 7/4/22 02:58, Stafford Horne wrote:
> -static const MemoryRegionOps goldfish_rtc_ops = {
> -    .read = goldfish_rtc_read,
> -    .write = goldfish_rtc_write,
> -    .endianness = DEVICE_NATIVE_ENDIAN,
> -    .valid = {
> -        .min_access_size = 4,
> -        .max_access_size = 4
> -    }
> +static const MemoryRegionOps goldfish_rtc_ops[3] = {
> +    [DEVICE_NATIVE_ENDIAN] = {
> +        .read = goldfish_rtc_read,
> +        .write = goldfish_rtc_write,
> +        .endianness = DEVICE_NATIVE_ENDIAN,
> +        .valid = {
> +            .min_access_size = 4,
> +            .max_access_size = 4
> +        }
> +    },
> +    [DEVICE_LITTLE_ENDIAN] = {
> +        .read = goldfish_rtc_read,
> +        .write = goldfish_rtc_write,
> +        .endianness = DEVICE_LITTLE_ENDIAN,
> +        .valid = {
> +            .min_access_size = 4,
> +            .max_access_size = 4
> +        }
> +    },
> +    [DEVICE_BIG_ENDIAN] = {
> +        .read = goldfish_rtc_read,
> +        .write = goldfish_rtc_write,
> +        .endianness = DEVICE_BIG_ENDIAN,
> +        .valid = {
> +            .min_access_size = 4,
> +            .max_access_size = 4
> +        }
> +    },
>   };

You don't need 3 copies, only big and little.

> +static Property goldfish_rtc_properties[] = {
> +    DEFINE_PROP_UINT8("endianness", GoldfishRTCState, endianness,
> +                      DEVICE_NATIVE_ENDIAN),
> +    DEFINE_PROP_END_OF_LIST(),
> +};

... and I think the clear desire for default is little-endian.  I would make the property 
be bool, and add a comment that this is only for m68k compatibility, so don't use it in 
new code.


r~