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Diffstat (limited to 'drivers/idle/intel_idle.c')
-rw-r--r--drivers/idle/intel_idle.c39
1 files changed, 31 insertions, 8 deletions
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index 118fe1d37c22..348c49d50a96 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -56,6 +56,7 @@
#include <asm/intel-family.h>
#include <asm/mwait.h>
#include <asm/spec-ctrl.h>
+#include <asm/tsc.h>
#include <asm/fpu/api.h>
#define INTEL_IDLE_VERSION "0.5.1"
@@ -89,7 +90,6 @@ struct idle_cpu {
* Indicate which enable bits to clear here.
*/
unsigned long auto_demotion_disable_flags;
- bool byt_auto_demotion_disable_flag;
bool disable_promotion_to_c1e;
bool use_acpi;
};
@@ -1463,13 +1463,11 @@ static const struct idle_cpu idle_cpu_snx __initconst = {
static const struct idle_cpu idle_cpu_byt __initconst = {
.state_table = byt_cstates,
.disable_promotion_to_c1e = true,
- .byt_auto_demotion_disable_flag = true,
};
static const struct idle_cpu idle_cpu_cht __initconst = {
.state_table = cht_cstates,
.disable_promotion_to_c1e = true,
- .byt_auto_demotion_disable_flag = true,
};
static const struct idle_cpu idle_cpu_ivb __initconst = {
@@ -1695,6 +1693,10 @@ static bool force_use_acpi __read_mostly; /* No effect if no_acpi is set. */
module_param_named(use_acpi, force_use_acpi, bool, 0444);
MODULE_PARM_DESC(use_acpi, "Use ACPI _CST for building the idle states list");
+static bool no_native __read_mostly; /* No effect if no_acpi is set. */
+module_param_named(no_native, no_native, bool, 0444);
+MODULE_PARM_DESC(no_native, "Ignore cpu specific (native) idle states in lieu of ACPI idle states");
+
static struct acpi_processor_power acpi_state_table __initdata;
/**
@@ -1799,6 +1801,9 @@ static void __init intel_idle_init_cstates_acpi(struct cpuidle_driver *drv)
if (intel_idle_state_needs_timer_stop(state))
state->flags |= CPUIDLE_FLAG_TIMER_STOP;
+ if (cx->type > ACPI_STATE_C1 && !boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
+ mark_tsc_unstable("TSC halts in idle");
+
state->enter = intel_idle;
state->enter_s2idle = intel_idle_s2idle;
}
@@ -1834,6 +1839,11 @@ static bool __init intel_idle_off_by_default(unsigned int flags, u32 mwait_hint)
}
return true;
}
+
+static inline bool ignore_native(void)
+{
+ return no_native && !no_acpi;
+}
#else /* !CONFIG_ACPI_PROCESSOR_CSTATE */
#define force_use_acpi (false)
@@ -1843,6 +1853,7 @@ static inline bool intel_idle_off_by_default(unsigned int flags, u32 mwait_hint)
{
return false;
}
+static inline bool ignore_native(void) { return false; }
#endif /* !CONFIG_ACPI_PROCESSOR_CSTATE */
/**
@@ -2055,6 +2066,15 @@ static void __init spr_idle_state_table_update(void)
}
}
+/**
+ * byt_cht_auto_demotion_disable - Disable Bay/Cherry Trail auto-demotion.
+ */
+static void __init byt_cht_auto_demotion_disable(void)
+{
+ wrmsrl(MSR_CC6_DEMOTION_POLICY_CONFIG, 0);
+ wrmsrl(MSR_MC6_DEMOTION_POLICY_CONFIG, 0);
+}
+
static bool __init intel_idle_verify_cstate(unsigned int mwait_hint)
{
unsigned int mwait_cstate = (MWAIT_HINT2CSTATE(mwait_hint) + 1) &
@@ -2136,6 +2156,10 @@ static void __init intel_idle_init_cstates_icpu(struct cpuidle_driver *drv)
case INTEL_ATOM_GRACEMONT:
adl_idle_state_table_update();
break;
+ case INTEL_ATOM_SILVERMONT:
+ case INTEL_ATOM_AIRMONT:
+ byt_cht_auto_demotion_disable();
+ break;
}
for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) {
@@ -2178,11 +2202,6 @@ static void __init intel_idle_init_cstates_icpu(struct cpuidle_driver *drv)
drv->state_count++;
}
-
- if (icpu->byt_auto_demotion_disable_flag) {
- wrmsrl(MSR_CC6_DEMOTION_POLICY_CONFIG, 0);
- wrmsrl(MSR_MC6_DEMOTION_POLICY_CONFIG, 0);
- }
}
/**
@@ -2328,6 +2347,10 @@ static int __init intel_idle_init(void)
pr_debug("MWAIT substates: 0x%x\n", mwait_substates);
icpu = (const struct idle_cpu *)id->driver_data;
+ if (icpu && ignore_native()) {
+ pr_debug("ignoring native CPU idle states\n");
+ icpu = NULL;
+ }
if (icpu) {
if (icpu->state_table)
cpuidle_state_table = icpu->state_table;