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cacheinfo: Check cache properties are present in DT

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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: de0df442ee ("cacheinfo: Check 'cache-unified' property to count cache leaves")
Reported-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/all/20230404-hatred-swimmer-6fecdf33b57a@spud/
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230414081453.244787-3-pierre.gondois@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
This commit is contained in:
Pierre Gondois 2023-04-14 10:14:50 +02:00 committed by Sudeep Holla
parent 7a306e3eab
commit cde0fbff07
1 changed files with 32 additions and 0 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

32
drivers/base/cacheinfo.c
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@ -78,6 +78,9 @@ bool last_level_cache_is_shared(unsigned int cpu_x, unsigned int cpu_y)
}
#ifdef CONFIG_OF
static bool of_check_cache_nodes(struct device_node *np);
/* OF properties to query for a given cache type */
struct cache_type_info {
const char *size_prop;
@ -205,6 +208,11 @@ static int cache_setup_of_node(unsigned int cpu)
return -ENOENT;
}
if (!of_check_cache_nodes(np)) {
of_node_put(np);
return -ENOENT;
}
prev = np;
while (index < cache_leaves(cpu)) {
@ -229,6 +237,25 @@ static int cache_setup_of_node(unsigned int cpu)
return 0;
}
static bool of_check_cache_nodes(struct device_node *np)
{
struct device_node *next;
if (of_property_present(np, "cache-size") ||
of_property_present(np, "i-cache-size") ||
of_property_present(np, "d-cache-size") ||
of_property_present(np, "cache-unified"))
return true;
next = of_find_next_cache_node(np);
if (next) {
of_node_put(next);
return true;
}
return false;
}
static int of_count_cache_leaves(struct device_node *np)
{
unsigned int leaves = 0;
@ -260,6 +287,11 @@ int init_of_cache_level(unsigned int cpu)
struct device_node *prev = NULL;
unsigned int levels = 0, leaves, level;
if (!of_check_cache_nodes(np)) {
of_node_put(np);
return -ENOENT;
}
leaves = of_count_cache_leaves(np);
if (leaves > 0)
levels = 1;