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authorLinus Torvalds <torvalds@linux-foundation.org>2022-08-01 09:36:18 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-08-01 09:36:18 -0700
commit650ea1f626ab4d939fda00b7cca57698dcf57e5e (patch)
tree1d75b3c2449d76ca17264f827255975d61d3e70d /drivers/idle
parent92598ae22f582547ebb060cf76f5869bc9780b80 (diff)
parent9f01129382774d98ec21526f13da26a0630ee3d8 (diff)
Merge tag 'x86_fpu_for_v6.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fpu update from Borislav Petkov: - Add machinery to initialize AMX register state in order for AMX-capable CPUs to be able to enter deeper low-power state * tag 'x86_fpu_for_v6.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: intel_idle: Add a new flag to initialize the AMX state x86/fpu: Add a helper to prepare AMX state for low-power CPU idle
Diffstat (limited to 'drivers/idle')
-rw-r--r--drivers/idle/intel_idle.c25
1 files changed, 23 insertions, 2 deletions
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index 907700d1e78e..445b19d20b9a 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -56,6 +56,7 @@
#include <asm/nospec-branch.h>
#include <asm/mwait.h>
#include <asm/msr.h>
+#include <asm/fpu/api.h>
#define INTEL_IDLE_VERSION "0.5.1"
@@ -114,6 +115,11 @@ static unsigned int mwait_substates __initdata;
#define CPUIDLE_FLAG_IBRS BIT(16)
/*
+ * Initialize large xstate for the C6-state entrance.
+ */
+#define CPUIDLE_FLAG_INIT_XSTATE BIT(17)
+
+/*
* MWAIT takes an 8-bit "hint" in EAX "suggesting"
* the C-state (top nibble) and sub-state (bottom nibble)
* 0x00 means "MWAIT(C1)", 0x10 means "MWAIT(C2)" etc.
@@ -191,6 +197,13 @@ static __cpuidle int intel_idle_ibrs(struct cpuidle_device *dev,
return ret;
}
+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);
+}
+
/**
* intel_idle_s2idle - Ask the processor to enter the given idle state.
* @dev: cpuidle device of the target CPU.
@@ -206,8 +219,12 @@ static __cpuidle int intel_idle_ibrs(struct cpuidle_device *dev,
static __cpuidle int intel_idle_s2idle(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int index)
{
- unsigned long eax = flg2MWAIT(drv->states[index].flags);
unsigned long ecx = 1; /* break on interrupt flag */
+ struct cpuidle_state *state = &drv->states[index];
+ unsigned long eax = flg2MWAIT(state->flags);
+
+ if (state->flags & CPUIDLE_FLAG_INIT_XSTATE)
+ fpu_idle_fpregs();
mwait_idle_with_hints(eax, ecx);
@@ -942,7 +959,8 @@ static struct cpuidle_state spr_cstates[] __initdata = {
{
.name = "C6",
.desc = "MWAIT 0x20",
- .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED |
+ CPUIDLE_FLAG_INIT_XSTATE,
.exit_latency = 290,
.target_residency = 800,
.enter = &intel_idle,
@@ -1857,6 +1875,9 @@ static void __init intel_idle_init_cstates_icpu(struct cpuidle_driver *drv)
drv->states[drv->state_count].enter = intel_idle_ibrs;
}
+ if (cpuidle_state_table[cstate].flags & CPUIDLE_FLAG_INIT_XSTATE)
+ drv->states[drv->state_count].enter = intel_idle_xstate;
+
if ((disabled_states_mask & BIT(drv->state_count)) ||
((icpu->use_acpi || force_use_acpi) &&
intel_idle_off_by_default(mwait_hint) &&