intel-idle: convert to x86_cpu_id auto probing
Andi Kleen [Wed, 25 Jan 2012 23:09:07 +0000 (00:09 +0100)]
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>

drivers/idle/intel_idle.c

index 20bce51..ef6a409 100644 (file)
@@ -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;