intel_idle: disable Atom/Lincroft HW C-state auto-demotion

Just as we had to disable auto-demotion for NHM/WSM, we need to do the same for Atom (Lincroft version). In particular, auto-demotion will prevent Lincroft from entering the S0i3 idle power saving state. https://bugzilla.kernel.org/show_bug.cgi?id=25252 Signed-off-by: Len Brown <len.brown@intel.com>
git-mirror · Feb 17, 2011 · bfb53cc · bfb53cc
1 parent 14796fc
commit bfb53cc
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diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
@@ -39,6 +39,7 @@
 #define MSR_NHM_SNB_PKG_CST_CFG_CTL	0x000000e2
 #define NHM_C3_AUTO_DEMOTE		(1UL << 25)
 #define NHM_C1_AUTO_DEMOTE		(1UL << 26)
+#define ATM_LNC_C6_AUTO_DEMOTE		(1UL << 25)
 
 #define MSR_MTRRcap			0x000000fe
 #define MSR_IA32_BBL_CR_CTL		0x00000119

diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
@@ -345,8 +345,12 @@ static int intel_idle_probe(void)
 		break;
 
 	case 0x1C:	/* 28 - Atom Processor */
+		cpuidle_state_table = atom_cstates;
+		break;
+
 	case 0x26:	/* 38 - Lincroft Atom Processor */
 		cpuidle_state_table = atom_cstates;
+		auto_demotion_disable_flags = ATM_LNC_C6_AUTO_DEMOTE;
 		break;
 
 	case 0x2A:	/* SNB */