Re: [PATCH 4/4] msm: scm: Get cacheline size from CTR

From: Stephen Boyd
Date: Thu Feb 24 2011 - 14:50:56 EST


On 02/24/2011 11:32 AM, Sergei Shtylyov wrote:
> Stephen Boyd wrote:
>
>> @@ -207,6 +204,14 @@ static int __scm_call(const struct scm_command
>> *cmd)
>> return ret;
>> }
>>
>> +static inline u32 dcache_line_size(void)
>> +{
>> + u32 ctr;
>> +
>> + asm volatile("mrc p15, 0, %0, c0, c0, 1" : "=r" (ctr));
>> + return 4 << ((ctr >> 16) & 0xf);
>> +}
>
> Won't generic cache_line_size() macro do instead? It's defined as
> L1_CACHE_BYTES.
>

Interesting. It would be the same value (32) but I'm not sure how
multi-platform friendly that will be since L1_CACHE_BYTES is (1 <<
CONFIG_ARM_L1_CACHE_SHIFT). I suppose we can punt supporting platforms
with different cache line sizes in one kernel for another day.

--
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.

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