Merge: Update intel_idle to support MTL

MR: https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/4685

JIRA: https://issues.redhat.com/browse/RHEL-47255    
  
Signed-off-by: David Arcari <darcari@redhat.com>

Approved-by: Waiman Long <longman@redhat.com>
Approved-by: Steve Best <sbest@redhat.com>
Approved-by: CKI KWF Bot <cki-ci-bot+kwf-gitlab-com@redhat.com>

Merged-by: Lucas Zampieri <lzampier@redhat.com>

Author: zampierilucas

arch/x86/include/asm/mwait.h

@@ -117,7 +117,7 @@ static __always_inline void mwait_idle_with_hints(unsigned long eax, unsigned lo
 			mb();
 		}
 
-		if (irqs_disabled() &&
+		if (irqs_disabled() && (ecx & 1) &&
 		    cpu_feature_enabled(X86_FEATURE_KERNEL_IBRS)) {
 			/* NMI always enable IBRS on exception entry */
 			ibrs_disabled = true;
@@ -127,9 +127,15 @@ static __always_inline void mwait_idle_with_hints(unsigned long eax, unsigned lo
 		}
 
 		__monitor((void *)&current_thread_info()->flags, 0, 0);
-		if (!need_resched())
-			__mwait(eax, ecx);
 
+		if (!need_resched()) {
+			if (ecx & 1) {
+				__mwait(eax, ecx);
+			} else {
+				__sti_mwait(eax, ecx);
+				raw_local_irq_disable();
+			}
+		}
 		if (ibrs_disabled) {
 			native_wrmsrl(MSR_IA32_SPEC_CTRL, spec_ctrl);
 			__this_cpu_write(x86_spec_ctrl_current, spec_ctrl);

arch/x86/kernel/acpi/cstate.c

@@ -131,8 +131,8 @@ static long acpi_processor_ffh_cstate_probe_cpu(void *_cx)
 	cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &edx);
 
 	/* Check whether this particular cx_type (in CST) is supported or not */
-	cstate_type = ((cx->address >> MWAIT_SUBSTATE_SIZE) &
-			MWAIT_CSTATE_MASK) + 1;
+	cstate_type = (((cx->address >> MWAIT_SUBSTATE_SIZE) &
+			MWAIT_CSTATE_MASK) + 1) & MWAIT_CSTATE_MASK;
 	edx_part = edx >> (cstate_type * MWAIT_SUBSTATE_SIZE);
 	num_cstate_subtype = edx_part & MWAIT_SUBSTATE_MASK;
 

drivers/idle/intel_idle.c

@@ -131,11 +131,12 @@ static unsigned int mwait_substates __initdata;
 #define MWAIT2flg(eax) ((eax & 0xFF) << 24)
 
 static __always_inline int __intel_idle(struct cpuidle_device *dev,
-					struct cpuidle_driver *drv, int index)
+					struct cpuidle_driver *drv,
+					int index, bool irqoff)
 {
 	struct cpuidle_state *state = &drv->states[index];
 	unsigned long eax = flg2MWAIT(state->flags);
-	unsigned long ecx = 1; /* break on interrupt flag */
+	unsigned long ecx = 1*irqoff; /* break on interrupt flag */
 
 	mwait_idle_with_hints(eax, ecx);
 
@@ -159,19 +160,13 @@ static __always_inline int __intel_idle(struct cpuidle_device *dev,
 static __cpuidle int intel_idle(struct cpuidle_device *dev,
 				struct cpuidle_driver *drv, int index)
 {
-	return __intel_idle(dev, drv, index);
+	return __intel_idle(dev, drv, index, true);
 }
 
 static __cpuidle int intel_idle_irq(struct cpuidle_device *dev,
 				    struct cpuidle_driver *drv, int index)
 {
-	int ret;
-
-	raw_local_irq_enable();
-	ret = __intel_idle(dev, drv, index);
-	raw_local_irq_disable();
-
-	return ret;
+	return __intel_idle(dev, drv, index, false);
 }
 
 static __cpuidle int intel_idle_ibrs(struct cpuidle_device *dev,
@@ -184,7 +179,7 @@ static __cpuidle int intel_idle_ibrs(struct cpuidle_device *dev,
 	if (smt_active)
 		__update_spec_ctrl(0);
 
-	ret = __intel_idle(dev, drv, index);
+	ret = __intel_idle(dev, drv, index, true);
 
 	if (smt_active)
 		__update_spec_ctrl(spec_ctrl);
@@ -196,7 +191,7 @@ static __cpuidle int intel_idle_xstate(struct cpuidle_device *dev,
 				       struct cpuidle_driver *drv, int index)
 {
 	fpu_idle_fpregs();
-	return __intel_idle(dev, drv, index);
+	return __intel_idle(dev, drv, index, true);
 }
 
 /**
@@ -923,6 +918,35 @@ static struct cpuidle_state adl_l_cstates[] __initdata = {
 		.enter = NULL }
 };
 
+static struct cpuidle_state mtl_l_cstates[] __initdata = {
+	{
+		.name = "C1E",
+		.desc = "MWAIT 0x01",
+		.flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE,
+		.exit_latency = 1,
+		.target_residency = 1,
+		.enter = &intel_idle,
+		.enter_s2idle = intel_idle_s2idle, },
+	{
+		.name = "C6",
+		.desc = "MWAIT 0x20",
+		.flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
+		.exit_latency = 140,
+		.target_residency = 420,
+		.enter = &intel_idle,
+		.enter_s2idle = intel_idle_s2idle, },
+	{
+		.name = "C10",
+		.desc = "MWAIT 0x60",
+		.flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED,
+		.exit_latency = 310,
+		.target_residency = 930,
+		.enter = &intel_idle,
+		.enter_s2idle = intel_idle_s2idle, },
+	{
+		.enter = NULL }
+};
+
 static struct cpuidle_state gmt_cstates[] __initdata = {
 	{
 		.name = "C1",
@@ -1415,6 +1439,10 @@ static const struct idle_cpu idle_cpu_adl_l __initconst = {
 	.state_table = adl_l_cstates,
 };
 
+static const struct idle_cpu idle_cpu_mtl_l __initconst = {
+	.state_table = mtl_l_cstates,
+};
+
 static const struct idle_cpu idle_cpu_gmt __initconst = {
 	.state_table = gmt_cstates,
 };
@@ -1501,6 +1529,7 @@ static const struct x86_cpu_id intel_idle_ids[] __initconst = {
 	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_D,		&idle_cpu_icx),
 	X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE,		&idle_cpu_adl),
 	X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE_L,		&idle_cpu_adl_l),
+	X86_MATCH_INTEL_FAM6_MODEL(METEORLAKE_L,	&idle_cpu_mtl_l),
 	X86_MATCH_INTEL_FAM6_MODEL(ATOM_GRACEMONT,	&idle_cpu_gmt),
 	X86_MATCH_INTEL_FAM6_MODEL(SAPPHIRERAPIDS_X,	&idle_cpu_spr),
 	X86_MATCH_INTEL_FAM6_MODEL(EMERALDRAPIDS_X,	&idle_cpu_spr),
@@ -1905,7 +1934,8 @@ static void __init spr_idle_state_table_update(void)
 
 static bool __init intel_idle_verify_cstate(unsigned int mwait_hint)
 {
-	unsigned int mwait_cstate = MWAIT_HINT2CSTATE(mwait_hint) + 1;
+	unsigned int mwait_cstate = (MWAIT_HINT2CSTATE(mwait_hint) + 1) &
+					MWAIT_CSTATE_MASK;
 	unsigned int num_substates = (mwait_substates >> mwait_cstate * 4) &
 					MWAIT_SUBSTATE_MASK;