Re: [PATCH] blackfin: include: asm: pgtable: Define dummy pgprot_writecombine

[Chen Gang]

On 4/4/15 06:50, Richard Weinberger wrote:
> On Fri, Apr 3, 2015 at 10:36 PM, Chen Gang <xili_gchen_5257@xxxxxxxxxxx> wrote:
>> It is copied from asm-generic, the related error with allmodconfig:
>>
>>     CC [M]  sound/core/pcm_native.o
>>   sound/core/pcm_native.c: In function 'snd_pcm_lib_default_mmap':
>>   sound/core/pcm_native.c:3387:24: error: implicit declaration of function 'pgprot_writecombine' [-Werror=implicit-function-declaration]
>>      area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
>>                           ^
>>   sound/core/pcm_native.c:3387:22: error: incompatible types when assigning to type 'pgprot_t {aka struct <anonymous>}' from type 'int'
>>      area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
>>                         ^
>>
>> Signed-off-by: Chen Gang <gang.chen.5i5j@xxxxxxxxx>
>> ---
>>  arch/blackfin/include/asm/pgtable.h | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/arch/blackfin/include/asm/pgtable.h b/arch/blackfin/include/asm/pgtable.h
>> index b88a155..3e730d9 100644
>> --- a/arch/blackfin/include/asm/pgtable.h
>> +++ b/arch/blackfin/include/asm/pgtable.h
>> @@ -36,6 +36,7 @@ typedef pte_t *pte_addr_t;
>>  #define PAGE_READONLY          __pgprot(0)     /* these mean nothing to NO_MM */
>>  #define PAGE_KERNEL            __pgprot(0)     /* these mean nothing to NO_MM */
>>  #define pgprot_noncached(prot) (prot)
>> +#define pgprot_writecombine    pgprot_noncached
> 
> This looks fishy as blackfin's pgtable.h already includes asm-generic/pgtable.h.
> So, copy&pasting pgprot_writecombine shouldn't be needed.
> 

pgprot_writecombine in asm-generic/pgtable.h needs MMU, but allmodconfig
for blackfin is NOMMU.

So, I still suggest to add dummy one in blackfin (although for me, asm-
generic/pgtable.h may need improvement -- welcome other members for it).


Thanks.
-- 
Chen Gang

Open, share, and attitude like air, water, and life which God blessed
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/