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From: Kaushlendra Kumar <kaushlendra.kumar@intel.com>
To: rafael@kernel.org, artem.bityutskiy@linux.intel.com, lenb@kernel.org
Cc: linux-pm@vger.kernel.org,
	Kaushlendra Kumar <kaushlendra.kumar@intel.com>
Subject: [PATCH] intel_idle: Fix C6S and C10 latency values for Pantherlake
Date: Tue, 11 Aug 2026 13:47:29 +0530	[thread overview]
Message-ID: <20260811081729.186571-1-kaushlendra.kumar@intel.com> (raw)

Correct the values using BIOS ACPI _CST characterization data read from
a Pantherlake device via
/sys/devices/system/cpu/cpu0/cpuidle/stateN/{latency,residency}:

  C6S: exit_latency 300->127, target_residency 300->381
  C10: exit_latency 370->1048, target_residency 2500->3144

Signed-off-by: Kaushlendra Kumar <kaushlendra.kumar@intel.com>
---
 drivers/idle/intel_idle.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index 651408df9c24..0b5c94c7cd3a 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -1010,16 +1010,16 @@ static struct cpuidle_state ptl_cstates[] __initdata = {
 		.name = "C6S",
 		.desc = "MWAIT 0x21",
 		.flags = MWAIT2flg(0x21) | CPUIDLE_FLAG_TLB_FLUSHED,
-		.exit_latency = 300,
-		.target_residency = 300,
+		.exit_latency = 127,
+		.target_residency = 381,
 		.enter = &intel_idle,
 		.enter_s2idle = intel_idle_s2idle, },
 	{
 		.name = "C10",
 		.desc = "MWAIT 0x60",
 		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
-		.exit_latency = 370,
-		.target_residency = 2500,
+		.exit_latency = 1048,
+		.target_residency = 3144,
 		.enter = &intel_idle,
 		.enter_s2idle = intel_idle_s2idle, },
 	{
-- 
2.34.1


             reply	other threads:[~2026-08-11  8:21 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-11  8:17 Kaushlendra Kumar [this message]
2026-08-11 10:05 ` [PATCH] intel_idle: Fix C6S and C10 latency values for Pantherlake Artem Bityutskiy
2026-08-11 10:06 ` Artem Bityutskiy
2026-08-11 10:36   ` Kumar, Kaushlendra
2026-08-11 17:25     ` Artem Bityutskiy

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