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Diffstat (limited to 'drivers/idle/intel_idle.c')
-rw-r--r--drivers/idle/intel_idle.c111
1 files changed, 108 insertions, 3 deletions
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index 0b66e25c0e2d..b7640cfe0020 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -64,6 +64,7 @@ static struct cpuidle_driver intel_idle_driver = {
/* intel_idle.max_cstate=0 disables driver */
static int max_cstate = CPUIDLE_STATE_MAX - 1;
static unsigned int disabled_states_mask;
+static unsigned int preferred_states_mask;
static struct cpuidle_device __percpu *intel_idle_cpuidle_devices;
@@ -121,9 +122,6 @@ static unsigned int mwait_substates __initdata;
* If the local APIC timer is not known to be reliable in the target idle state,
* enable one-shot tick broadcasting for the target CPU before executing MWAIT.
*
- * Optionally call leave_mm() for the target CPU upfront to avoid wakeups due to
- * flushing user TLBs.
- *
* Must be called under local_irq_disable().
*/
static __cpuidle int intel_idle(struct cpuidle_device *dev,
@@ -761,6 +759,46 @@ static struct cpuidle_state icx_cstates[] __initdata = {
.enter = NULL }
};
+/*
+ * On Sapphire Rapids Xeon C1 has to be disabled if C1E is enabled, and vice
+ * versa. On SPR C1E is enabled only if "C1E promotion" bit is set in
+ * MSR_IA32_POWER_CTL. But in this case there effectively no C1, because C1
+ * requests are promoted to C1E. If the "C1E promotion" bit is cleared, then
+ * both C1 and C1E requests end up with C1, so there is effectively no C1E.
+ *
+ * By default we enable C1 and disable C1E by marking it with
+ * 'CPUIDLE_FLAG_UNUSABLE'.
+ */
+static struct cpuidle_state spr_cstates[] __initdata = {
+ {
+ .name = "C1",
+ .desc = "MWAIT 0x00",
+ .flags = MWAIT2flg(0x00),
+ .exit_latency = 1,
+ .target_residency = 1,
+ .enter = &intel_idle,
+ .enter_s2idle = intel_idle_s2idle, },
+ {
+ .name = "C1E",
+ .desc = "MWAIT 0x01",
+ .flags = MWAIT2flg(0x01) | CPUIDLE_FLAG_ALWAYS_ENABLE |
+ CPUIDLE_FLAG_UNUSABLE,
+ .exit_latency = 2,
+ .target_residency = 4,
+ .enter = &intel_idle,
+ .enter_s2idle = intel_idle_s2idle, },
+ {
+ .name = "C6",
+ .desc = "MWAIT 0x20",
+ .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
+ .exit_latency = 290,
+ .target_residency = 800,
+ .enter = &intel_idle,
+ .enter_s2idle = intel_idle_s2idle, },
+ {
+ .enter = NULL }
+};
+
static struct cpuidle_state atom_cstates[] __initdata = {
{
.name = "C1E",
@@ -1104,6 +1142,12 @@ static const struct idle_cpu idle_cpu_icx __initconst = {
.use_acpi = true,
};
+static const struct idle_cpu idle_cpu_spr __initconst = {
+ .state_table = spr_cstates,
+ .disable_promotion_to_c1e = true,
+ .use_acpi = true,
+};
+
static const struct idle_cpu idle_cpu_avn __initconst = {
.state_table = avn_cstates,
.disable_promotion_to_c1e = true,
@@ -1166,6 +1210,7 @@ static const struct x86_cpu_id intel_idle_ids[] __initconst = {
X86_MATCH_INTEL_FAM6_MODEL(SKYLAKE_X, &idle_cpu_skx),
X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_X, &idle_cpu_icx),
X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_D, &idle_cpu_icx),
+ X86_MATCH_INTEL_FAM6_MODEL(SAPPHIRERAPIDS_X, &idle_cpu_spr),
X86_MATCH_INTEL_FAM6_MODEL(XEON_PHI_KNL, &idle_cpu_knl),
X86_MATCH_INTEL_FAM6_MODEL(XEON_PHI_KNM, &idle_cpu_knl),
X86_MATCH_INTEL_FAM6_MODEL(ATOM_GOLDMONT, &idle_cpu_bxt),
@@ -1353,6 +1398,8 @@ static inline void intel_idle_init_cstates_acpi(struct cpuidle_driver *drv) { }
static inline bool intel_idle_off_by_default(u32 mwait_hint) { return false; }
#endif /* !CONFIG_ACPI_PROCESSOR_CSTATE */
+static void c1e_promotion_enable(void);
+
/**
* ivt_idle_state_table_update - Tune the idle states table for Ivy Town.
*
@@ -1523,6 +1570,41 @@ static void __init skx_idle_state_table_update(void)
}
}
+/**
+ * spr_idle_state_table_update - Adjust Sapphire Rapids idle states table.
+ */
+static void __init spr_idle_state_table_update(void)
+{
+ unsigned long long msr;
+
+ /* Check if user prefers C1E over C1. */
+ if (preferred_states_mask & BIT(2)) {
+ if (preferred_states_mask & BIT(1))
+ /* Both can't be enabled, stick to the defaults. */
+ return;
+
+ spr_cstates[0].flags |= CPUIDLE_FLAG_UNUSABLE;
+ spr_cstates[1].flags &= ~CPUIDLE_FLAG_UNUSABLE;
+
+ /* Enable C1E using the "C1E promotion" bit. */
+ c1e_promotion_enable();
+ disable_promotion_to_c1e = false;
+ }
+
+ /*
+ * By default, the C6 state assumes the worst-case scenario of package
+ * C6. However, if PC6 is disabled, we update the numbers to match
+ * core C6.
+ */
+ rdmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr);
+
+ /* Limit value 2 and above allow for PC6. */
+ if ((msr & 0x7) < 2) {
+ spr_cstates[2].exit_latency = 190;
+ spr_cstates[2].target_residency = 600;
+ }
+}
+
static bool __init intel_idle_verify_cstate(unsigned int mwait_hint)
{
unsigned int mwait_cstate = MWAIT_HINT2CSTATE(mwait_hint) + 1;
@@ -1557,6 +1639,9 @@ static void __init intel_idle_init_cstates_icpu(struct cpuidle_driver *drv)
case INTEL_FAM6_SKYLAKE_X:
skx_idle_state_table_update();
break;
+ case INTEL_FAM6_SAPPHIRERAPIDS_X:
+ spr_idle_state_table_update();
+ break;
}
for (cstate = 0; cstate < CPUIDLE_STATE_MAX; ++cstate) {
@@ -1629,6 +1714,15 @@ static void auto_demotion_disable(void)
wrmsrl(MSR_PKG_CST_CONFIG_CONTROL, msr_bits);
}
+static void c1e_promotion_enable(void)
+{
+ unsigned long long msr_bits;
+
+ rdmsrl(MSR_IA32_POWER_CTL, msr_bits);
+ msr_bits |= 0x2;
+ wrmsrl(MSR_IA32_POWER_CTL, msr_bits);
+}
+
static void c1e_promotion_disable(void)
{
unsigned long long msr_bits;
@@ -1798,3 +1892,14 @@ module_param(max_cstate, int, 0444);
*/
module_param_named(states_off, disabled_states_mask, uint, 0444);
MODULE_PARM_DESC(states_off, "Mask of disabled idle states");
+/*
+ * Some platforms come with mutually exclusive C-states, so that if one is
+ * enabled, the other C-states must not be used. Example: C1 and C1E on
+ * Sapphire Rapids platform. This parameter allows for selecting the
+ * preferred C-states among the groups of mutually exclusive C-states - the
+ * selected C-states will be registered, the other C-states from the mutually
+ * exclusive group won't be registered. If the platform has no mutually
+ * exclusive C-states, this parameter has no effect.
+ */
+module_param_named(preferred_cstates, preferred_states_mask, uint, 0444);
+MODULE_PARM_DESC(preferred_cstates, "Mask of preferred idle states");