aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/kernel/acpi/cstate.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/acpi/cstate.c')
-rw-r--r--arch/x86/kernel/acpi/cstate.c27
1 files changed, 15 insertions, 12 deletions
diff --git a/arch/x86/kernel/acpi/cstate.c b/arch/x86/kernel/acpi/cstate.c
index 2e837f5080f..4b28159e042 100644
--- a/arch/x86/kernel/acpi/cstate.c
+++ b/arch/x86/kernel/acpi/cstate.c
@@ -13,6 +13,8 @@
#include <acpi/processor.h>
#include <asm/acpi.h>
+#include <asm/mwait.h>
+#include <asm/special_insns.h>
/*
* Initialize bm_flags based on the CPU cache properties
@@ -61,20 +63,10 @@ struct cstate_entry {
unsigned int ecx;
} states[ACPI_PROCESSOR_MAX_POWER];
};
-static struct cstate_entry *cpu_cstate_entry; /* per CPU ptr */
+static struct cstate_entry __percpu *cpu_cstate_entry; /* per CPU ptr */
static short mwait_supported[ACPI_PROCESSOR_MAX_POWER];
-#define MWAIT_SUBSTATE_MASK (0xf)
-#define MWAIT_CSTATE_MASK (0xf)
-#define MWAIT_SUBSTATE_SIZE (4)
-
-#define CPUID_MWAIT_LEAF (5)
-#define CPUID5_ECX_EXTENSIONS_SUPPORTED (0x1)
-#define CPUID5_ECX_INTERRUPT_BREAK (0x2)
-
-#define MWAIT_ECX_INTERRUPT_BREAK (0x1)
-
#define NATIVE_CSTATE_BEYOND_HALT (2)
static long acpi_processor_ffh_cstate_probe_cpu(void *_cx)
@@ -95,7 +87,9 @@ static long acpi_processor_ffh_cstate_probe_cpu(void *_cx)
num_cstate_subtype = edx_part & MWAIT_SUBSTATE_MASK;
retval = 0;
- if (num_cstate_subtype < (cx->address & MWAIT_SUBSTATE_MASK)) {
+ /* If the HW does not support any sub-states in this C-state */
+ if (num_cstate_subtype == 0) {
+ pr_warn(FW_BUG "ACPI MWAIT C-state 0x%x not supported by HW (0x%x)\n", cx->address, edx_part);
retval = -1;
goto out;
}
@@ -145,6 +139,15 @@ int acpi_processor_ffh_cstate_probe(unsigned int cpu,
percpu_entry->states[cx->index].eax = cx->address;
percpu_entry->states[cx->index].ecx = MWAIT_ECX_INTERRUPT_BREAK;
}
+
+ /*
+ * For _CST FFH on Intel, if GAS.access_size bit 1 is cleared,
+ * then we should skip checking BM_STS for this C-state.
+ * ref: "Intel Processor Vendor-Specific ACPI Interface Specification"
+ */
+ if ((c->x86_vendor == X86_VENDOR_INTEL) && !(reg->access_size & 0x2))
+ cx->bm_sts_skip = 1;
+
return retval;
}
EXPORT_SYMBOL_GPL(acpi_processor_ffh_cstate_probe);