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>

2 files changed, 5 insertions, 0 deletions

diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index b75eeab2b1ea..43a18c77676d 100644
--- 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
index 32b25bcaf865..4a5c4a44ffb1 100644
--- 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 */