intel-idle: convert to x86_cpu_id auto probing

With this it should be automatically loaded on suitable systems by
udev.

The old switch () is replaced with a table based approach, this
also cleans up the code.

Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 66 insertions, 50 deletions

diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index 20bce51c2e8..ef6a409ff1a 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -62,6 +62,7 @@
 #include <linux/notifier.h>
 #include <linux/cpu.h>
 #include <linux/module.h>
+#include <asm/cpu_device_id.h>
 #include <asm/mwait.h>
 #include <asm/msr.h>
 
@@ -81,6 +82,17 @@ static unsigned int mwait_substates;
 /* Reliable LAPIC Timer States, bit 1 for C1 etc.  */
 static unsigned int lapic_timer_reliable_states = (1 << 1);      /* Default to only C1 */
 
+struct idle_cpu {
+        struct cpuidle_state *state_table;
+
+        /*
+         * Hardware C-state auto-demotion may not always be optimal.
+         * Indicate which enable bits to clear here.
+         */
+        unsigned long auto_demotion_disable_flags;
+};
+
+static const struct idle_cpu *icpu;
 static struct cpuidle_device __percpu *intel_idle_cpuidle_devices;
 static int intel_idle(struct cpuidle_device *dev,
                         struct cpuidle_driver *drv, int index);
@@ -88,12 +100,6 @@ static int intel_idle(struct cpuidle_device *dev,
 static struct cpuidle_state *cpuidle_state_table;
 
 /*
- * Hardware C-state auto-demotion may not always be optimal.
- * Indicate which enable bits to clear here.
- */
-static unsigned long long auto_demotion_disable_flags;
-
-/*
  * Set this flag for states where the HW flushes the TLB for us
  * and so we don't need cross-calls to keep it consistent.
  * If this flag is set, SW flushes the TLB, so even if the
@@ -319,27 +325,72 @@ static void auto_demotion_disable(void *dummy)
         unsigned long long msr_bits;
 
         rdmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits);
-        msr_bits &= ~auto_demotion_disable_flags;
+        msr_bits &= ~(icpu->auto_demotion_disable_flags);
         wrmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits);
 }
 
+static const struct idle_cpu idle_cpu_nehalem = {
+        .state_table = nehalem_cstates,
+};
+
+static const struct idle_cpu idle_cpu_westmere = {
+        .state_table = nehalem_cstates,
+        .auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE,
+};
+
+static const struct idle_cpu idle_cpu_atom = {
+        .state_table = atom_cstates,
+};
+
+static const struct idle_cpu idle_cpu_lincroft = {
+        .state_table = atom_cstates,
+        .auto_demotion_disable_flags = ATM_LNC_C6_AUTO_DEMOTE,
+};
+
+static const struct idle_cpu idle_cpu_snb = {
+        .state_table = snb_cstates,
+};
+
+#define ICPU(model, cpu) \
+        { X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT, (unsigned long)&cpu }
+
+static const struct x86_cpu_id intel_idle_ids[] = {
+        ICPU(0x1a, idle_cpu_nehalem),
+        ICPU(0x1e, idle_cpu_nehalem),
+        ICPU(0x1f, idle_cpu_nehalem),
+        ICPU(0x25, idle_cpu_westmere),
+        ICPU(0x2c, idle_cpu_westmere),
+        ICPU(0x2f, idle_cpu_westmere),
+        ICPU(0x1c, idle_cpu_atom),
+        ICPU(0x26, idle_cpu_lincroft),
+        ICPU(0x2f, idle_cpu_westmere),
+        ICPU(0x2a, idle_cpu_snb),
+        ICPU(0x2d, idle_cpu_snb),
+        {}
+};
+MODULE_DEVICE_TABLE(x86cpu, intel_idle_ids);
+
 /*
  * intel_idle_probe()
  */
 static int intel_idle_probe(void)
 {
         unsigned int eax, ebx, ecx;
+        const struct x86_cpu_id *id;
 
         if (max_cstate == 0) {
                 pr_debug(PREFIX "disabled\n");
                 return -EPERM;
         }
 
-        if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
-                return -ENODEV;
-
-        if (!boot_cpu_has(X86_FEATURE_MWAIT))
+        id = x86_match_cpu(intel_idle_ids);
+        if (!id) {
+                if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
+                    boot_cpu_data.x86 == 6)
+                        pr_debug(PREFIX "does not run on family %d model %d\n",
+                                boot_cpu_data.x86, boot_cpu_data.x86_model);
                 return -ENODEV;
+        }
 
         if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
                 return -ENODEV;
@@ -353,43 +404,8 @@ static int intel_idle_probe(void)
 
         pr_debug(PREFIX "MWAIT substates: 0x%x\n", mwait_substates);
 
-
-        if (boot_cpu_data.x86 != 6)     /* family 6 */
-                return -ENODEV;
-
-        switch (boot_cpu_data.x86_model) {
-
-        case 0x1A:      /* Core i7, Xeon 5500 series */
-        case 0x1E:      /* Core i7 and i5 Processor - Lynnfield Jasper Forest */
-        case 0x1F:      /* Core i7 and i5 Processor - Nehalem */
-        case 0x2E:      /* Nehalem-EX Xeon */
-        case 0x2F:      /* Westmere-EX Xeon */
-        case 0x25:      /* Westmere */
-        case 0x2C:      /* Westmere */
-                cpuidle_state_table = nehalem_cstates;
-                auto_demotion_disable_flags =
-                        (NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE);
-                break;
-
-        case 0x1C:      /* 28 - Atom Processor */
-                cpuidle_state_table = atom_cstates;
-                break;
-
-        case 0x26:      /* 38 - Lincroft Atom Processor */
-                cpuidle_state_table = atom_cstates;
-                auto_demotion_disable_flags = ATM_LNC_C6_AUTO_DEMOTE;
-                break;
-
-        case 0x2A:      /* SNB */
-        case 0x2D:      /* SNB Xeon */
-                cpuidle_state_table = snb_cstates;
-                break;
-
-        default:
-                pr_debug(PREFIX "does not run on family %d model %d\n",
-                        boot_cpu_data.x86, boot_cpu_data.x86_model);
-                return -ENODEV;
-        }
+        icpu = (const struct idle_cpu *)id->driver_data;
+        cpuidle_state_table = icpu->state_table;
 
         if (boot_cpu_has(X86_FEATURE_ARAT))     /* Always Reliable APIC Timer */
                 lapic_timer_reliable_states = LAPIC_TIMER_ALWAYS_RELIABLE;
@@ -470,7 +486,7 @@ static int intel_idle_cpuidle_driver_init(void)
                 drv->state_count += 1;
         }
 
-        if (auto_demotion_disable_flags)
+        if (icpu->auto_demotion_disable_flags)
                 on_each_cpu(auto_demotion_disable, NULL, 1);
 
         return 0;
@@ -522,7 +538,7 @@ int intel_idle_cpu_init(int cpu)
                 return -EIO;
         }
 
-        if (auto_demotion_disable_flags)
+        if (icpu->auto_demotion_disable_flags)
                 smp_call_function_single(cpu, auto_demotion_disable, NULL, 1);
 
         return 0;