[PATCH] powercap: intel_rapl: Don't warn about BIOS locked limits during resume

From: Ville Syrjala
Date: Wed Oct 04 2023 - 14:35:06 EST


From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>

Restore enough of the original behaviour to stop spamming
dmesg with warnings about BIOS locked limits when trying
to restore them during resume.

This still doesn't 100% match the original behaviour
as we no longer attempt to blindly restore the BIOS locked
limits. No idea if that makes any difference in practice.

Cc: Zhang Rui <rui.zhang@xxxxxxxxx>
Cc: Wang Wendy <wendy.wang@xxxxxxxxx>
Cc: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Cc: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxx>
Fixes: 9050a9cd5e4c ("powercap: intel_rapl: Cleanup Power Limits support")
Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
---
drivers/powercap/intel_rapl_common.c | 28 ++++++++++++++++++++--------
1 file changed, 20 insertions(+), 8 deletions(-)

diff --git a/drivers/powercap/intel_rapl_common.c b/drivers/powercap/intel_rapl_common.c
index 40a2cc649c79..9a6a40c83f82 100644
--- a/drivers/powercap/intel_rapl_common.c
+++ b/drivers/powercap/intel_rapl_common.c
@@ -882,22 +882,34 @@ static int rapl_read_pl_data(struct rapl_domain *rd, int pl,
return rapl_read_data_raw(rd, prim, xlate, data);
}

-static int rapl_write_pl_data(struct rapl_domain *rd, int pl,
- enum pl_prims pl_prim,
- unsigned long long value)
+static int rapl_write_pl_data_nowarn(struct rapl_domain *rd, int pl,
+ enum pl_prims pl_prim,
+ unsigned long long value)
{
enum rapl_primitives prim = get_pl_prim(rd, pl, pl_prim);

if (!is_pl_valid(rd, pl))
return -EINVAL;

- if (rd->rpl[pl].locked) {
- pr_warn("%s:%s:%s locked by BIOS\n", rd->rp->name, rd->name, pl_names[pl]);
+ if (rd->rpl[pl].locked)
return -EACCES;
- }

return rapl_write_data_raw(rd, prim, value);
}
+
+static int rapl_write_pl_data(struct rapl_domain *rd, int pl,
+ enum pl_prims pl_prim,
+ unsigned long long value)
+{
+ int ret;
+
+ ret = rapl_write_pl_data_nowarn(rd, pl, pl_prim, value);
+ if (ret == -EACCES)
+ pr_warn("%s:%s:%s locked by BIOS\n", rd->rp->name, rd->name, pl_names[pl]);
+
+ return ret;
+}
+
/*
* Raw RAPL data stored in MSRs are in certain scales. We need to
* convert them into standard units based on the units reported in
@@ -1634,8 +1646,8 @@ static void power_limit_state_restore(void)
rd = power_zone_to_rapl_domain(rp->power_zone);
for (i = POWER_LIMIT1; i < NR_POWER_LIMITS; i++)
if (rd->rpl[i].last_power_limit)
- rapl_write_pl_data(rd, i, PL_LIMIT,
- rd->rpl[i].last_power_limit);
+ rapl_write_pl_data_nowarn(rd, i, PL_LIMIT,
+ rd->rpl[i].last_power_limit);
}
cpus_read_unlock();
}
--
2.41.0