[U-Boot] [PATCH v3 2/4] ARM: cache: add an empty stub function for invalidate/flush dcache

[York Sun]

Josh,

No you didn't miss. I think you are right on this file.

York

Sent from my cellphone


-------- Original message --------
From: Josh Wu
Date:07/27/2015 22:07 (GMT-08:00)
To: Sun York-R58495 , U-Boot Mailing List , Marek Vasut , Tom Rini
Cc: Masahiro Yamada , Jeroen Hofstee , Valentine Barshak , Simon Glass , Thierry Reding , Masahiro Yamada , Heiko Schocher , Albert Aribaud , Nobuhiro Iwamatsu
Subject: Re: [PATCH v3 2/4] ARM: cache: add an empty stub function for invalidate/flush dcache

Hi, York

On 7/28/2015 12:24 PM, York Sun wrote:
Please search the same name function in the same file.

yes, there still have flush_dcache_range() & invalidate_dcache_range() function defined in case of DCACHE is enabled (CONFIG_SYS_DCACHE_OFF is not defined).
And in that case, the empty weak functions flush_dcache_range() & invalidate_dcache_range() in arch/arm/lib/cache.c will be ignored. It is an expect behavior.

or did I miss something?

Best Regards,
Josh Wu


York

Sent from my cellphone


-------- Original message --------
From: Josh Wu
Date:07/27/2015 19:17 (GMT-08:00)
To: Sun York-R58495 , U-Boot Mailing List , Marek Vasut , Tom Rini
Cc: Masahiro Yamada , Jeroen Hofstee , Valentine Barshak , Simon Glass , Thierry Reding , Masahiro Yamada , Heiko Schocher , Albert Aribaud , Nobuhiro Iwamatsu
Subject: Re: [PATCH v3 2/4] ARM: cache: add an empty stub function for invalidate/flush dcache

Hi, York

On 7/28/2015 12:31 AM, York Sun wrote:
>
> On 07/26/2015 08:40 PM, Josh Wu wrote:
>> Since some driver like ohci, lcd used dcache functions. But some ARM
>> cpu don't implement the invalidate_dcache_range()/flush_dcache_range()
>> functions.
>>
>> To avoid compiling errors this patch adds an weak empty stub function
>> for all ARM cpu in arch/arm/lib/cache.c.
>> And ARM cpu still can implemnt its own cache functions on the cpu folder.
>>
>> Signed-off-by: Josh Wu <josh.wu at atmel.com><mailto:josh.wu at atmel.com>
>> ---
>>
>> Changes in v3:
>> - remove the same functions in the cpu/ files as they will use the weak
>>    function provided in lib/cache.c
>>
>> Changes in v2:
>> - new added.
>>
> <snip>
>
>> diff --git a/arch/arm/cpu/armv8/cache_v8.c b/arch/arm/cpu/armv8/cache_v8.c
>> index c5ec529..f8c17cc 100644
>> --- a/arch/arm/cpu/armv8/cache_v8.c
>> +++ b/arch/arm/cpu/armv8/cache_v8.c
>> @@ -149,14 +149,6 @@ void flush_dcache_all(void)
>>   {
>>   }
>>
>> -void invalidate_dcache_range(unsigned long start, unsigned long stop)
>> -{
>> -}
>> -
>> -void flush_dcache_range(unsigned long start, unsigned long stop)
>> -{
>> -}
>> -
>>   void dcache_enable(void)
>>   {
>>   }
> Are you sure about this change?

This patch deletes those above empty functions so that the driver will
use the same weak empty functions in arch/arm/lib/cache.c, which is
added by this patch as well.

> You are probably changing the wrong leg of the
> #if conditional code.

I don't think so. Could give me more details about this? Thanks.

Best Regards,
Josh Wu

>
> York