Re: [PATCH v3 2/4] cacheinfo: Check cache properties are present in DT

From: Pierre Gondois
Date: Fri Apr 14 2023 - 04:20:13 EST


Hello Florian,

On 4/13/23 20:16, Florian Fainelli wrote:
On 4/13/23 02:14, Pierre Gondois wrote:
If a Device Tree (DT) is used, the presence of cache properties is
assumed. Not finding any is not considered. For arm64 platforms,
cache information can be fetched from the clidr_el1 register.
Checking whether cache information is available in the DT
allows to switch to using clidr_el1.

init_of_cache_level()
\-of_count_cache_leaves()
will assume there a 2 cache leaves (L1 data/instruction caches), which
can be different from clidr_el1 information.

cache_setup_of_node() tries to read cache properties in the DT.
If there are none, this is considered a success. Knowing no
information was available would allow to switch to using clidr_el1.

Fixes: de0df442ee49 ("cacheinfo: Check 'cache-unified' property to count cache leaves")
Reported-by: Alexandre Ghiti <alexghiti@xxxxxxxxxxxx>
Link: https://lore.kernel.org/all/20230404-hatred-swimmer-6fecdf33b57a@spud/
Signed-off-by: Pierre Gondois <pierre.gondois@xxxxxxx>

Humm, it would appear that the cache levels and topology is still
provided, despite the lack of cache properties in the Device Tree which
is intended by this patch set however we lost the size/ways/sets
information, could we not complement the missing properties here?

If this is out of the scope of what you are doing:

Tested-by: Florian Fainelli <f.fainelli@xxxxxxxxx>

I submitted a v4 at:
https://lore.kernel.org/all/20230414081453.244787-1-pierre.gondois@xxxxxxx/

I haven't included your Tested-by as there were some small changes.
If you consider these changes are small enough to include your tag,
please let know,

Regards,
Pierre