linux-kernel - [PATCH 4/4] intel_idle: Move BYT/CHT auto-demotion fixup into fix_this

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Date:	Sun, 13 Mar 2016 21:48:13 -0700
From:	Andy Lutomirski <luto@...nel.org>
To:	len.brown@...el.com
Cc:	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Andy Lutomirski <luto@...nel.org>
Subject: [PATCH 4/4] intel_idle: Move BYT/CHT auto-demotion fixup into fix_this_cpu

The demotion policy config registers are per-package and these CPUs
only exist in single-package variants AFAIK, so it's not stricly
necessary to fix these MSRs on each core, but fixing them on resume
is still likely to be helpful, so move them into fix_this_cpu.

Signed-off-by: Andy Lutomirski <luto@...nel.org>
---
 drivers/idle/intel_idle.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index e3d7d8bbc843..cbb02d28dc48 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -826,6 +826,11 @@ static void fix_this_cpu(void *dummy)
 		msr_bits &= ~0x2;
 		wrmsrl(MSR_IA32_POWER_CTL, msr_bits);
 	}
+
+	if (icpu->byt_auto_demotion_disable_flag) {
+		wrmsrl(MSR_CC6_DEMOTION_POLICY_CONFIG, 0);
+		wrmsrl(MSR_MC6_DEMOTION_POLICY_CONFIG, 0);
+	}
 }
 
 static const struct idle_cpu idle_cpu_nehalem = {
@@ -1084,11 +1089,6 @@ static int __init intel_idle_cpuidle_driver_init(void)
 		drv->state_count += 1;
 	}
 
-	if (icpu->byt_auto_demotion_disable_flag) {
-		wrmsrl(MSR_CC6_DEMOTION_POLICY_CONFIG, 0);
-		wrmsrl(MSR_MC6_DEMOTION_POLICY_CONFIG, 0);
-	}
-
 	return 0;
 }
 
-- 
2.5.0