On 19/07/17 10:01, Christoffer Dall wrote:
> On Thu, Jun 29, 2017 at 07:06:44PM +0100, Sudeep Holla wrote:
>> We already have various macros related to cache type and bitfields in
>> CLIDR system register. We can replace some of the hardcoded values
>> here using those existing macros.
>>
>> This patch reuses those existing cache type/info related macros and
>> replaces the hardcorded values. It also removes some of the comments
>> that become trivial with the macro names.
>>
>> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
>> Cc: Will Deacon <will.deacon@xxxxxxx>
>> Cc: Christoffer Dall <christoffer.dall@xxxxxxxxxx>
>> Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
>> Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
>> ---
>> arch/arm64/include/asm/cache.h | 7 +++++++
>> arch/arm64/kernel/cacheinfo.c | 7 -------
>> arch/arm64/kvm/sys_regs.c | 29 +++++++++++++++--------------
>> 3 files changed, 22 insertions(+), 21 deletions(-)
>>
[...]
>> /* Which cache CCSIDR represents depends on CSSELR value. */
>> static u32 get_ccsidr(u32 csselr)
>> @@ -1894,19 +1896,18 @@ static bool is_valid_cache(u32 val)
>> return false;
>>
>> /* Bottom bit is Instruction or Data bit. Next 3 bits are level. */
>> - level = (val >> 1);
>> - ctype = (cache_levels >> (level * 3)) & 7;
>> + level = (val >> 1) + 1;
>> + ctype = CLIDR_CTYPE(cache_levels, level);
>>
>> switch (ctype) {
>> - case 0: /* No cache */
>> - return false;
>> - case 1: /* Instruction cache only */
>> - return (val & 1);
>> - case 2: /* Data cache only */
>> - case 4: /* Unified cache */
>> - return !(val & 1);
>> - case 3: /* Separate instruction and data caches */
>> + case CACHE_TYPE_INST:
>> + return (val & CACHE_TYPE_INST);
>> + case CACHE_TYPE_DATA:
>> + case CACHE_TYPE_UNIFIED:
>> + return !(val & CACHE_TYPE_INST);
>> + case CACHE_TYPE_SEPARATE:
>> return true;
>> + case CACHE_TYPE_NOCACHE:
>> default: /* Reserved: we can't know instruction or data. */
>> return false;
>> }
>
> These defines seem to be arch-generic concepts defined in
> include/linux/cacheinfo.h. Are they guaranteed to not change and
> therefore always match the format of ARM registers?
>
Indeed, I have added the mapping code for other architectures which
doesn't match. We can do the same when ARM deviates :)
> Otherwise, this looks good to me.
>
Thanks, Will/Marc had requested to repost after -rc1, will do that ASAP.
--
Regards,
Sudeep
