On Fri, Feb 20, 2015 at 8:00 PM, Matt Turner <mattst88@xxxxxxxxx> wrote:
> On Fri, Feb 20, 2015 at 1:53 AM, Robert P. J. Day <rpjday@xxxxxxxxxxxxxx> wrote:
>>
>> was recently handed a MIPS-based dev board (can't name the vendor,
>> NDA) that *typically* runs in LE mode but, because of a proprietary
>> binary that must be run on the board and was compiled as BE, has to be
>> run in BE mode.
>>
>> the vendor supplied a yoctoproject layer that seems to work fine
>> but, in changing the DEFAULTTUNE to big-endian, the following patch
>> had to be applied to the 3.14 kernel tree to the file
>> arch/mips/include/asm/io.h in order to get output from the console
>> port as the system was booting:
>>
>> 326c326,333
>> < *__mem = __val; \
>> ---
>>> { \
>>> if (sizeof(type) == sizeof(u32)) \
>>> { \
>>> *__mem = __cpu_to_le32(__val); \
>
> They're byte swapping a value if they're in big endian mode.
>
>>> } \
>>> else \
>>> *__mem = __val; \
>
> And they don't seem to really understand the __cpu_to_le32 macro...
Sorry, I should be more precise. They're byte swapping 32-bit values
if they're in big endian mode, and copying everything else without
conversion.
