On 12/01/17 13:24, Rob Herring wrote:
> On Tue, Jan 10, 2017 at 6:00 AM, Sudeep Holla <[email protected]> wrote:
>> It is useful to have helper function just to get the number of cache
>> levels for a given logical cpu. This patch adds the support for the
>> same.
>>
>> It will be used on ARM64 platform where the device tree provides the
>> information for the additional non-architected/transparent/external
>> last level caches that are not integrated with the processors.
>>
>> Cc: Rob Herring <[email protected]>
>> Cc: Mark Rutland <[email protected]>
>> Signed-off-by: Sudeep Holla <[email protected]>
>> ---
>> drivers/of/base.c | 23 +++++++++++++++++++++++
>> include/linux/of.h | 1 +
>> 2 files changed, 24 insertions(+)
>>
[...]
>> +int of_count_cache_levels(unsigned int cpu)
>> +{
>> + int level = 0;
>> + struct device_node *np = of_cpu_device_node_get(cpu);
>> +
>> + while (np) {
>> + level++;
>
> This will return 1 if you have a cpu node and no cache nodes. Are you
> assuming the cpu has a cache?
>
Ah right, that's completely wrong assumption.
> Perhaps you should just find the last level cache node and then just
> read "cache-level".
>
Yes, sounds better. I will update accordingly. Thanks for the suggestion.
--
Regards,
Sudeep
