intel_idle: initial IVB support

commit 6edab08c upstream.

From an OS point of view, IVB looks like SNB, but quicker.
Signed-off-by: Len Brown <len.brown@intel.com>
[bwh: Backported to 3.2: add model number to the switch in
 intel_idle_probe(), as there is no device ID table]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/idle/intel_idle.c

@@ -163,6 +163,38 @@ static struct cpuidle_state snb_cstates[MWAIT_MAX_NUM_CSTATES] = {
 		.enter = &intel_idle },
 };
 
+static struct cpuidle_state ivb_cstates[MWAIT_MAX_NUM_CSTATES] = {
+	{ /* MWAIT C0 */ },
+	{ /* MWAIT C1 */
+		.name = "C1-IVB",
+		.desc = "MWAIT 0x00",
+		.flags = CPUIDLE_FLAG_TIME_VALID,
+		.exit_latency = 1,
+		.target_residency = 1,
+		.enter = &intel_idle },
+	{ /* MWAIT C2 */
+		.name = "C3-IVB",
+		.desc = "MWAIT 0x10",
+		.flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
+		.exit_latency = 59,
+		.target_residency = 156,
+		.enter = &intel_idle },
+	{ /* MWAIT C3 */
+		.name = "C6-IVB",
+		.desc = "MWAIT 0x20",
+		.flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
+		.exit_latency = 80,
+		.target_residency = 300,
+		.enter = &intel_idle },
+	{ /* MWAIT C4 */
+		.name = "C7-IVB",
+		.desc = "MWAIT 0x30",
+		.flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
+		.exit_latency = 87,
+		.target_residency = 300,
+		.enter = &intel_idle },
+};
+
 static struct cpuidle_state atom_cstates[MWAIT_MAX_NUM_CSTATES] = {
 	{ /* MWAIT C0 */ },
 	{ /* MWAIT C1 */
@@ -386,6 +418,10 @@ static int intel_idle_probe(void)
 		cpuidle_state_table = snb_cstates;
 		break;
 
+	case 0x3A:	/* IVB */
+		cpuidle_state_table = ivb_cstates;
+		break;
+
 	default:
 		pr_debug(PREFIX "does not run on family %d model %d\n",
 			boot_cpu_data.x86, boot_cpu_data.x86_model);