Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 1 | /* |
| 2 | * intel_idle.c - native hardware idle loop for modern Intel processors |
| 3 | * |
| 4 | * Copyright (c) 2010, Intel Corporation. |
| 5 | * Len Brown <len.brown@intel.com> |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify it |
| 8 | * under the terms and conditions of the GNU General Public License, |
| 9 | * version 2, as published by the Free Software Foundation. |
| 10 | * |
| 11 | * This program is distributed in the hope it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 14 | * more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License along with |
| 17 | * this program; if not, write to the Free Software Foundation, Inc., |
| 18 | * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. |
| 19 | */ |
| 20 | |
| 21 | /* |
| 22 | * intel_idle is a cpuidle driver that loads on specific Intel processors |
| 23 | * in lieu of the legacy ACPI processor_idle driver. The intent is to |
| 24 | * make Linux more efficient on these processors, as intel_idle knows |
| 25 | * more than ACPI, as well as make Linux more immune to ACPI BIOS bugs. |
| 26 | */ |
| 27 | |
| 28 | /* |
| 29 | * Design Assumptions |
| 30 | * |
| 31 | * All CPUs have same idle states as boot CPU |
| 32 | * |
| 33 | * Chipset BM_STS (bus master status) bit is a NOP |
| 34 | * for preventing entry into deep C-stats |
| 35 | */ |
| 36 | |
| 37 | /* |
| 38 | * Known limitations |
| 39 | * |
| 40 | * The driver currently initializes for_each_online_cpu() upon modprobe. |
| 41 | * It it unaware of subsequent processors hot-added to the system. |
| 42 | * This means that if you boot with maxcpus=n and later online |
| 43 | * processors above n, those processors will use C1 only. |
| 44 | * |
| 45 | * ACPI has a .suspend hack to turn off deep c-statees during suspend |
| 46 | * to avoid complications with the lapic timer workaround. |
| 47 | * Have not seen issues with suspend, but may need same workaround here. |
| 48 | * |
| 49 | * There is currently no kernel-based automatic probing/loading mechanism |
| 50 | * if the driver is built as a module. |
| 51 | */ |
| 52 | |
| 53 | /* un-comment DEBUG to enable pr_debug() statements */ |
| 54 | #define DEBUG |
| 55 | |
| 56 | #include <linux/kernel.h> |
| 57 | #include <linux/cpuidle.h> |
| 58 | #include <linux/clockchips.h> |
| 59 | #include <linux/hrtimer.h> /* ktime_get_real() */ |
| 60 | #include <trace/events/power.h> |
| 61 | #include <linux/sched.h> |
Shaohua Li | 2a2d31c | 2011-01-10 09:38:12 +0800 | [diff] [blame] | 62 | #include <linux/notifier.h> |
| 63 | #include <linux/cpu.h> |
Paul Gortmaker | 7c52d55 | 2011-05-27 12:33:10 -0400 | [diff] [blame] | 64 | #include <linux/module.h> |
H. Peter Anvin | bc83ccc | 2010-09-17 15:36:40 -0700 | [diff] [blame] | 65 | #include <asm/mwait.h> |
Len Brown | 14796fc | 2011-01-18 20:48:27 -0500 | [diff] [blame] | 66 | #include <asm/msr.h> |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 67 | |
| 68 | #define INTEL_IDLE_VERSION "0.4" |
| 69 | #define PREFIX "intel_idle: " |
| 70 | |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 71 | static struct cpuidle_driver intel_idle_driver = { |
| 72 | .name = "intel_idle", |
| 73 | .owner = THIS_MODULE, |
| 74 | }; |
| 75 | /* intel_idle.max_cstate=0 disables driver */ |
| 76 | static int max_cstate = MWAIT_MAX_NUM_CSTATES - 1; |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 77 | |
Len Brown | c423628 | 2010-05-28 02:22:03 -0400 | [diff] [blame] | 78 | static unsigned int mwait_substates; |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 79 | |
Shaohua Li | 2a2d31c | 2011-01-10 09:38:12 +0800 | [diff] [blame] | 80 | #define LAPIC_TIMER_ALWAYS_RELIABLE 0xFFFFFFFF |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 81 | /* Reliable LAPIC Timer States, bit 1 for C1 etc. */ |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 82 | static unsigned int lapic_timer_reliable_states = (1 << 1); /* Default to only C1 */ |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 83 | |
Namhyung Kim | 3265eba | 2010-08-08 03:10:03 +0900 | [diff] [blame] | 84 | static struct cpuidle_device __percpu *intel_idle_cpuidle_devices; |
Deepthi Dharwar | 46bcfad | 2011-10-28 16:20:42 +0530 | [diff] [blame] | 85 | static int intel_idle(struct cpuidle_device *dev, |
| 86 | struct cpuidle_driver *drv, int index); |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 87 | |
| 88 | static struct cpuidle_state *cpuidle_state_table; |
| 89 | |
| 90 | /* |
Len Brown | 14796fc | 2011-01-18 20:48:27 -0500 | [diff] [blame] | 91 | * Hardware C-state auto-demotion may not always be optimal. |
| 92 | * Indicate which enable bits to clear here. |
| 93 | */ |
| 94 | static unsigned long long auto_demotion_disable_flags; |
| 95 | |
| 96 | /* |
Len Brown | 956d033 | 2011-01-12 02:51:20 -0500 | [diff] [blame] | 97 | * Set this flag for states where the HW flushes the TLB for us |
| 98 | * and so we don't need cross-calls to keep it consistent. |
| 99 | * If this flag is set, SW flushes the TLB, so even if the |
| 100 | * HW doesn't do the flushing, this flag is safe to use. |
| 101 | */ |
| 102 | #define CPUIDLE_FLAG_TLB_FLUSHED 0x10000 |
| 103 | |
| 104 | /* |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 105 | * States are indexed by the cstate number, |
| 106 | * which is also the index into the MWAIT hint array. |
| 107 | * Thus C0 is a dummy. |
| 108 | */ |
| 109 | static struct cpuidle_state nehalem_cstates[MWAIT_MAX_NUM_CSTATES] = { |
| 110 | { /* MWAIT C0 */ }, |
| 111 | { /* MWAIT C1 */ |
Thomas Renninger | 15e123e | 2011-02-27 22:36:43 +0100 | [diff] [blame] | 112 | .name = "C1-NHM", |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 113 | .desc = "MWAIT 0x00", |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 114 | .flags = CPUIDLE_FLAG_TIME_VALID, |
| 115 | .exit_latency = 3, |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 116 | .target_residency = 6, |
| 117 | .enter = &intel_idle }, |
| 118 | { /* MWAIT C2 */ |
Thomas Renninger | 15e123e | 2011-02-27 22:36:43 +0100 | [diff] [blame] | 119 | .name = "C3-NHM", |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 120 | .desc = "MWAIT 0x10", |
Suresh Siddha | 6110a1f | 2010-09-30 21:19:07 -0400 | [diff] [blame] | 121 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 122 | .exit_latency = 20, |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 123 | .target_residency = 80, |
| 124 | .enter = &intel_idle }, |
| 125 | { /* MWAIT C3 */ |
Thomas Renninger | 15e123e | 2011-02-27 22:36:43 +0100 | [diff] [blame] | 126 | .name = "C6-NHM", |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 127 | .desc = "MWAIT 0x20", |
Suresh Siddha | 6110a1f | 2010-09-30 21:19:07 -0400 | [diff] [blame] | 128 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 129 | .exit_latency = 200, |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 130 | .target_residency = 800, |
| 131 | .enter = &intel_idle }, |
| 132 | }; |
| 133 | |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 134 | static struct cpuidle_state snb_cstates[MWAIT_MAX_NUM_CSTATES] = { |
| 135 | { /* MWAIT C0 */ }, |
| 136 | { /* MWAIT C1 */ |
Thomas Renninger | 15e123e | 2011-02-27 22:36:43 +0100 | [diff] [blame] | 137 | .name = "C1-SNB", |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 138 | .desc = "MWAIT 0x00", |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 139 | .flags = CPUIDLE_FLAG_TIME_VALID, |
| 140 | .exit_latency = 1, |
Len Brown | ddbd550 | 2010-12-13 18:28:22 -0500 | [diff] [blame] | 141 | .target_residency = 1, |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 142 | .enter = &intel_idle }, |
| 143 | { /* MWAIT C2 */ |
Thomas Renninger | 15e123e | 2011-02-27 22:36:43 +0100 | [diff] [blame] | 144 | .name = "C3-SNB", |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 145 | .desc = "MWAIT 0x10", |
Len Brown | 00527cc | 2010-10-23 02:33:50 -0400 | [diff] [blame] | 146 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 147 | .exit_latency = 80, |
Len Brown | ddbd550 | 2010-12-13 18:28:22 -0500 | [diff] [blame] | 148 | .target_residency = 211, |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 149 | .enter = &intel_idle }, |
| 150 | { /* MWAIT C3 */ |
Thomas Renninger | 15e123e | 2011-02-27 22:36:43 +0100 | [diff] [blame] | 151 | .name = "C6-SNB", |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 152 | .desc = "MWAIT 0x20", |
Len Brown | 00527cc | 2010-10-23 02:33:50 -0400 | [diff] [blame] | 153 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 154 | .exit_latency = 104, |
Len Brown | ddbd550 | 2010-12-13 18:28:22 -0500 | [diff] [blame] | 155 | .target_residency = 345, |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 156 | .enter = &intel_idle }, |
| 157 | { /* MWAIT C4 */ |
Thomas Renninger | 15e123e | 2011-02-27 22:36:43 +0100 | [diff] [blame] | 158 | .name = "C7-SNB", |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 159 | .desc = "MWAIT 0x30", |
Len Brown | 00527cc | 2010-10-23 02:33:50 -0400 | [diff] [blame] | 160 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 161 | .exit_latency = 109, |
Len Brown | ddbd550 | 2010-12-13 18:28:22 -0500 | [diff] [blame] | 162 | .target_residency = 345, |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 163 | .enter = &intel_idle }, |
| 164 | }; |
| 165 | |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 166 | static struct cpuidle_state atom_cstates[MWAIT_MAX_NUM_CSTATES] = { |
| 167 | { /* MWAIT C0 */ }, |
| 168 | { /* MWAIT C1 */ |
Thomas Renninger | 15e123e | 2011-02-27 22:36:43 +0100 | [diff] [blame] | 169 | .name = "C1-ATM", |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 170 | .desc = "MWAIT 0x00", |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 171 | .flags = CPUIDLE_FLAG_TIME_VALID, |
| 172 | .exit_latency = 1, |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 173 | .target_residency = 4, |
| 174 | .enter = &intel_idle }, |
| 175 | { /* MWAIT C2 */ |
Thomas Renninger | 15e123e | 2011-02-27 22:36:43 +0100 | [diff] [blame] | 176 | .name = "C2-ATM", |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 177 | .desc = "MWAIT 0x10", |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 178 | .flags = CPUIDLE_FLAG_TIME_VALID, |
| 179 | .exit_latency = 20, |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 180 | .target_residency = 80, |
| 181 | .enter = &intel_idle }, |
| 182 | { /* MWAIT C3 */ }, |
| 183 | { /* MWAIT C4 */ |
Thomas Renninger | 15e123e | 2011-02-27 22:36:43 +0100 | [diff] [blame] | 184 | .name = "C4-ATM", |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 185 | .desc = "MWAIT 0x30", |
Suresh Siddha | 6110a1f | 2010-09-30 21:19:07 -0400 | [diff] [blame] | 186 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 187 | .exit_latency = 100, |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 188 | .target_residency = 400, |
| 189 | .enter = &intel_idle }, |
| 190 | { /* MWAIT C5 */ }, |
| 191 | { /* MWAIT C6 */ |
Thomas Renninger | 15e123e | 2011-02-27 22:36:43 +0100 | [diff] [blame] | 192 | .name = "C6-ATM", |
Len Brown | 7fcca7d | 2010-10-05 13:43:14 -0400 | [diff] [blame] | 193 | .desc = "MWAIT 0x52", |
Suresh Siddha | 6110a1f | 2010-09-30 21:19:07 -0400 | [diff] [blame] | 194 | .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED, |
Len Brown | 7fcca7d | 2010-10-05 13:43:14 -0400 | [diff] [blame] | 195 | .exit_latency = 140, |
Len Brown | 7fcca7d | 2010-10-05 13:43:14 -0400 | [diff] [blame] | 196 | .target_residency = 560, |
| 197 | .enter = &intel_idle }, |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 198 | }; |
| 199 | |
David Howells | 95e3ec1 | 2011-12-15 13:03:14 +0000 | [diff] [blame] | 200 | static long get_driver_data(int cstate) |
Deepthi Dharwar | 4202735 | 2011-10-28 16:20:33 +0530 | [diff] [blame] | 201 | { |
| 202 | int driver_data; |
| 203 | switch (cstate) { |
| 204 | |
| 205 | case 1: /* MWAIT C1 */ |
| 206 | driver_data = 0x00; |
| 207 | break; |
| 208 | case 2: /* MWAIT C2 */ |
| 209 | driver_data = 0x10; |
| 210 | break; |
| 211 | case 3: /* MWAIT C3 */ |
| 212 | driver_data = 0x20; |
| 213 | break; |
| 214 | case 4: /* MWAIT C4 */ |
| 215 | driver_data = 0x30; |
| 216 | break; |
| 217 | case 5: /* MWAIT C5 */ |
| 218 | driver_data = 0x40; |
| 219 | break; |
| 220 | case 6: /* MWAIT C6 */ |
| 221 | driver_data = 0x52; |
| 222 | break; |
| 223 | default: |
| 224 | driver_data = 0x00; |
| 225 | } |
| 226 | return driver_data; |
| 227 | } |
| 228 | |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 229 | /** |
| 230 | * intel_idle |
| 231 | * @dev: cpuidle_device |
Deepthi Dharwar | 46bcfad | 2011-10-28 16:20:42 +0530 | [diff] [blame] | 232 | * @drv: cpuidle driver |
Deepthi Dharwar | e978aa7 | 2011-10-28 16:20:09 +0530 | [diff] [blame] | 233 | * @index: index of cpuidle state |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 234 | * |
Yanmin Zhang | 63ff07b | 2012-01-10 15:48:21 -0800 | [diff] [blame] | 235 | * Must be called under local_irq_disable(). |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 236 | */ |
Deepthi Dharwar | 46bcfad | 2011-10-28 16:20:42 +0530 | [diff] [blame] | 237 | static int intel_idle(struct cpuidle_device *dev, |
| 238 | struct cpuidle_driver *drv, int index) |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 239 | { |
| 240 | unsigned long ecx = 1; /* break on interrupt flag */ |
Deepthi Dharwar | 46bcfad | 2011-10-28 16:20:42 +0530 | [diff] [blame] | 241 | struct cpuidle_state *state = &drv->states[index]; |
Deepthi Dharwar | 4202735 | 2011-10-28 16:20:33 +0530 | [diff] [blame] | 242 | struct cpuidle_state_usage *state_usage = &dev->states_usage[index]; |
| 243 | unsigned long eax = (unsigned long)cpuidle_get_statedata(state_usage); |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 244 | unsigned int cstate; |
| 245 | ktime_t kt_before, kt_after; |
| 246 | s64 usec_delta; |
| 247 | int cpu = smp_processor_id(); |
| 248 | |
| 249 | cstate = (((eax) >> MWAIT_SUBSTATE_SIZE) & MWAIT_CSTATE_MASK) + 1; |
| 250 | |
Suresh Siddha | 6110a1f | 2010-09-30 21:19:07 -0400 | [diff] [blame] | 251 | /* |
Len Brown | c8381cc | 2010-10-15 20:43:06 -0400 | [diff] [blame] | 252 | * leave_mm() to avoid costly and often unnecessary wakeups |
| 253 | * for flushing the user TLB's associated with the active mm. |
Suresh Siddha | 6110a1f | 2010-09-30 21:19:07 -0400 | [diff] [blame] | 254 | */ |
Len Brown | c8381cc | 2010-10-15 20:43:06 -0400 | [diff] [blame] | 255 | if (state->flags & CPUIDLE_FLAG_TLB_FLUSHED) |
Suresh Siddha | 6110a1f | 2010-09-30 21:19:07 -0400 | [diff] [blame] | 256 | leave_mm(cpu); |
| 257 | |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 258 | if (!(lapic_timer_reliable_states & (1 << (cstate)))) |
| 259 | clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &cpu); |
| 260 | |
| 261 | kt_before = ktime_get_real(); |
| 262 | |
| 263 | stop_critical_timings(); |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 264 | if (!need_resched()) { |
| 265 | |
| 266 | __monitor((void *)¤t_thread_info()->flags, 0, 0); |
| 267 | smp_mb(); |
| 268 | if (!need_resched()) |
| 269 | __mwait(eax, ecx); |
| 270 | } |
| 271 | |
| 272 | start_critical_timings(); |
| 273 | |
| 274 | kt_after = ktime_get_real(); |
| 275 | usec_delta = ktime_to_us(ktime_sub(kt_after, kt_before)); |
| 276 | |
| 277 | local_irq_enable(); |
| 278 | |
| 279 | if (!(lapic_timer_reliable_states & (1 << (cstate)))) |
| 280 | clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu); |
| 281 | |
Deepthi Dharwar | e978aa7 | 2011-10-28 16:20:09 +0530 | [diff] [blame] | 282 | /* Update cpuidle counters */ |
| 283 | dev->last_residency = (int)usec_delta; |
| 284 | |
| 285 | return index; |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 286 | } |
| 287 | |
Shaohua Li | 2a2d31c | 2011-01-10 09:38:12 +0800 | [diff] [blame] | 288 | static void __setup_broadcast_timer(void *arg) |
| 289 | { |
| 290 | unsigned long reason = (unsigned long)arg; |
| 291 | int cpu = smp_processor_id(); |
| 292 | |
| 293 | reason = reason ? |
| 294 | CLOCK_EVT_NOTIFY_BROADCAST_ON : CLOCK_EVT_NOTIFY_BROADCAST_OFF; |
| 295 | |
| 296 | clockevents_notify(reason, &cpu); |
| 297 | } |
| 298 | |
Shaohua Li | ec30f34 | 2011-01-24 08:00:01 +0000 | [diff] [blame] | 299 | static int setup_broadcast_cpuhp_notify(struct notifier_block *n, |
Shaohua Li | 2a2d31c | 2011-01-10 09:38:12 +0800 | [diff] [blame] | 300 | unsigned long action, void *hcpu) |
| 301 | { |
| 302 | int hotcpu = (unsigned long)hcpu; |
| 303 | |
| 304 | switch (action & 0xf) { |
| 305 | case CPU_ONLINE: |
| 306 | smp_call_function_single(hotcpu, __setup_broadcast_timer, |
| 307 | (void *)true, 1); |
| 308 | break; |
Shaohua Li | 2a2d31c | 2011-01-10 09:38:12 +0800 | [diff] [blame] | 309 | } |
| 310 | return NOTIFY_OK; |
| 311 | } |
| 312 | |
Shaohua Li | ec30f34 | 2011-01-24 08:00:01 +0000 | [diff] [blame] | 313 | static struct notifier_block setup_broadcast_notifier = { |
Shaohua Li | 2a2d31c | 2011-01-10 09:38:12 +0800 | [diff] [blame] | 314 | .notifier_call = setup_broadcast_cpuhp_notify, |
| 315 | }; |
| 316 | |
Len Brown | 14796fc | 2011-01-18 20:48:27 -0500 | [diff] [blame] | 317 | static void auto_demotion_disable(void *dummy) |
| 318 | { |
| 319 | unsigned long long msr_bits; |
| 320 | |
| 321 | rdmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits); |
| 322 | msr_bits &= ~auto_demotion_disable_flags; |
| 323 | wrmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits); |
| 324 | } |
| 325 | |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 326 | /* |
| 327 | * intel_idle_probe() |
| 328 | */ |
| 329 | static int intel_idle_probe(void) |
| 330 | { |
Len Brown | c423628 | 2010-05-28 02:22:03 -0400 | [diff] [blame] | 331 | unsigned int eax, ebx, ecx; |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 332 | |
| 333 | if (max_cstate == 0) { |
| 334 | pr_debug(PREFIX "disabled\n"); |
| 335 | return -EPERM; |
| 336 | } |
| 337 | |
| 338 | if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL) |
| 339 | return -ENODEV; |
| 340 | |
| 341 | if (!boot_cpu_has(X86_FEATURE_MWAIT)) |
| 342 | return -ENODEV; |
| 343 | |
| 344 | if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF) |
| 345 | return -ENODEV; |
| 346 | |
Len Brown | c423628 | 2010-05-28 02:22:03 -0400 | [diff] [blame] | 347 | cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &mwait_substates); |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 348 | |
| 349 | if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) || |
Thomas Renninger | 5c2a9f0 | 2011-12-04 22:17:29 +0100 | [diff] [blame^] | 350 | !(ecx & CPUID5_ECX_INTERRUPT_BREAK) || |
| 351 | !mwait_substates) |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 352 | return -ENODEV; |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 353 | |
Len Brown | c423628 | 2010-05-28 02:22:03 -0400 | [diff] [blame] | 354 | pr_debug(PREFIX "MWAIT substates: 0x%x\n", mwait_substates); |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 355 | |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 356 | |
| 357 | if (boot_cpu_data.x86 != 6) /* family 6 */ |
| 358 | return -ENODEV; |
| 359 | |
| 360 | switch (boot_cpu_data.x86_model) { |
| 361 | |
| 362 | case 0x1A: /* Core i7, Xeon 5500 series */ |
| 363 | case 0x1E: /* Core i7 and i5 Processor - Lynnfield Jasper Forest */ |
| 364 | case 0x1F: /* Core i7 and i5 Processor - Nehalem */ |
| 365 | case 0x2E: /* Nehalem-EX Xeon */ |
Len Brown | ec67a2b | 2010-07-26 23:40:19 -0400 | [diff] [blame] | 366 | case 0x2F: /* Westmere-EX Xeon */ |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 367 | case 0x25: /* Westmere */ |
| 368 | case 0x2C: /* Westmere */ |
| 369 | cpuidle_state_table = nehalem_cstates; |
Len Brown | 14796fc | 2011-01-18 20:48:27 -0500 | [diff] [blame] | 370 | auto_demotion_disable_flags = |
| 371 | (NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE); |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 372 | break; |
| 373 | |
| 374 | case 0x1C: /* 28 - Atom Processor */ |
Len Brown | bfb53cc | 2011-02-16 01:32:48 -0500 | [diff] [blame] | 375 | cpuidle_state_table = atom_cstates; |
| 376 | break; |
| 377 | |
Arjan van de Ven | 4725fd3 | 2010-07-21 23:42:25 -0400 | [diff] [blame] | 378 | case 0x26: /* 38 - Lincroft Atom Processor */ |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 379 | cpuidle_state_table = atom_cstates; |
Len Brown | bfb53cc | 2011-02-16 01:32:48 -0500 | [diff] [blame] | 380 | auto_demotion_disable_flags = ATM_LNC_C6_AUTO_DEMOTE; |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 381 | break; |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 382 | |
| 383 | case 0x2A: /* SNB */ |
| 384 | case 0x2D: /* SNB Xeon */ |
| 385 | cpuidle_state_table = snb_cstates; |
Len Brown | d13780d | 2010-07-07 00:12:03 -0400 | [diff] [blame] | 386 | break; |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 387 | |
| 388 | default: |
| 389 | pr_debug(PREFIX "does not run on family %d model %d\n", |
| 390 | boot_cpu_data.x86, boot_cpu_data.x86_model); |
| 391 | return -ENODEV; |
| 392 | } |
| 393 | |
Len Brown | 56b9aea | 2010-12-02 01:19:32 -0500 | [diff] [blame] | 394 | if (boot_cpu_has(X86_FEATURE_ARAT)) /* Always Reliable APIC Timer */ |
Shaohua Li | 2a2d31c | 2011-01-10 09:38:12 +0800 | [diff] [blame] | 395 | lapic_timer_reliable_states = LAPIC_TIMER_ALWAYS_RELIABLE; |
| 396 | else { |
Shaohua Li | 39a74fd | 2012-01-10 15:48:19 -0800 | [diff] [blame] | 397 | on_each_cpu(__setup_broadcast_timer, (void *)true, 1); |
Shaohua Li | 2a2d31c | 2011-01-10 09:38:12 +0800 | [diff] [blame] | 398 | register_cpu_notifier(&setup_broadcast_notifier); |
| 399 | } |
Len Brown | 56b9aea | 2010-12-02 01:19:32 -0500 | [diff] [blame] | 400 | |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 401 | pr_debug(PREFIX "v" INTEL_IDLE_VERSION |
| 402 | " model 0x%X\n", boot_cpu_data.x86_model); |
| 403 | |
| 404 | pr_debug(PREFIX "lapic_timer_reliable_states 0x%x\n", |
| 405 | lapic_timer_reliable_states); |
| 406 | return 0; |
| 407 | } |
| 408 | |
| 409 | /* |
| 410 | * intel_idle_cpuidle_devices_uninit() |
| 411 | * unregister, free cpuidle_devices |
| 412 | */ |
| 413 | static void intel_idle_cpuidle_devices_uninit(void) |
| 414 | { |
| 415 | int i; |
| 416 | struct cpuidle_device *dev; |
| 417 | |
| 418 | for_each_online_cpu(i) { |
| 419 | dev = per_cpu_ptr(intel_idle_cpuidle_devices, i); |
| 420 | cpuidle_unregister_device(dev); |
| 421 | } |
| 422 | |
| 423 | free_percpu(intel_idle_cpuidle_devices); |
| 424 | return; |
| 425 | } |
| 426 | /* |
Deepthi Dharwar | 46bcfad | 2011-10-28 16:20:42 +0530 | [diff] [blame] | 427 | * intel_idle_cpuidle_driver_init() |
| 428 | * allocate, initialize cpuidle_states |
| 429 | */ |
| 430 | static int intel_idle_cpuidle_driver_init(void) |
| 431 | { |
| 432 | int cstate; |
| 433 | struct cpuidle_driver *drv = &intel_idle_driver; |
| 434 | |
| 435 | drv->state_count = 1; |
| 436 | |
| 437 | for (cstate = 1; cstate < MWAIT_MAX_NUM_CSTATES; ++cstate) { |
| 438 | int num_substates; |
| 439 | |
| 440 | if (cstate > max_cstate) { |
| 441 | printk(PREFIX "max_cstate %d reached\n", |
| 442 | max_cstate); |
| 443 | break; |
| 444 | } |
| 445 | |
| 446 | /* does the state exist in CPUID.MWAIT? */ |
| 447 | num_substates = (mwait_substates >> ((cstate) * 4)) |
| 448 | & MWAIT_SUBSTATE_MASK; |
| 449 | if (num_substates == 0) |
| 450 | continue; |
| 451 | /* is the state not enabled? */ |
| 452 | if (cpuidle_state_table[cstate].enter == NULL) { |
| 453 | /* does the driver not know about the state? */ |
| 454 | if (*cpuidle_state_table[cstate].name == '\0') |
| 455 | pr_debug(PREFIX "unaware of model 0x%x" |
| 456 | " MWAIT %d please" |
| 457 | " contact lenb@kernel.org", |
| 458 | boot_cpu_data.x86_model, cstate); |
| 459 | continue; |
| 460 | } |
| 461 | |
| 462 | if ((cstate > 2) && |
| 463 | !boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) |
| 464 | mark_tsc_unstable("TSC halts in idle" |
| 465 | " states deeper than C2"); |
| 466 | |
| 467 | drv->states[drv->state_count] = /* structure copy */ |
| 468 | cpuidle_state_table[cstate]; |
| 469 | |
| 470 | drv->state_count += 1; |
| 471 | } |
| 472 | |
| 473 | if (auto_demotion_disable_flags) |
Shaohua Li | 39a74fd | 2012-01-10 15:48:19 -0800 | [diff] [blame] | 474 | on_each_cpu(auto_demotion_disable, NULL, 1); |
Deepthi Dharwar | 46bcfad | 2011-10-28 16:20:42 +0530 | [diff] [blame] | 475 | |
| 476 | return 0; |
| 477 | } |
| 478 | |
| 479 | |
| 480 | /* |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 481 | * intel_idle_cpuidle_devices_init() |
| 482 | * allocate, initialize, register cpuidle_devices |
| 483 | */ |
| 484 | static int intel_idle_cpuidle_devices_init(void) |
| 485 | { |
| 486 | int i, cstate; |
| 487 | struct cpuidle_device *dev; |
| 488 | |
| 489 | intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device); |
| 490 | if (intel_idle_cpuidle_devices == NULL) |
| 491 | return -ENOMEM; |
| 492 | |
| 493 | for_each_online_cpu(i) { |
| 494 | dev = per_cpu_ptr(intel_idle_cpuidle_devices, i); |
| 495 | |
| 496 | dev->state_count = 1; |
| 497 | |
| 498 | for (cstate = 1; cstate < MWAIT_MAX_NUM_CSTATES; ++cstate) { |
| 499 | int num_substates; |
| 500 | |
| 501 | if (cstate > max_cstate) { |
| 502 | printk(PREFIX "max_cstate %d reached\n", |
| 503 | max_cstate); |
| 504 | break; |
| 505 | } |
| 506 | |
| 507 | /* does the state exist in CPUID.MWAIT? */ |
Len Brown | c423628 | 2010-05-28 02:22:03 -0400 | [diff] [blame] | 508 | num_substates = (mwait_substates >> ((cstate) * 4)) |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 509 | & MWAIT_SUBSTATE_MASK; |
| 510 | if (num_substates == 0) |
| 511 | continue; |
| 512 | /* is the state not enabled? */ |
| 513 | if (cpuidle_state_table[cstate].enter == NULL) { |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 514 | continue; |
| 515 | } |
| 516 | |
Deepthi Dharwar | 4202735 | 2011-10-28 16:20:33 +0530 | [diff] [blame] | 517 | dev->states_usage[dev->state_count].driver_data = |
| 518 | (void *)get_driver_data(cstate); |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 519 | |
| 520 | dev->state_count += 1; |
| 521 | } |
| 522 | |
| 523 | dev->cpu = i; |
| 524 | if (cpuidle_register_device(dev)) { |
| 525 | pr_debug(PREFIX "cpuidle_register_device %d failed!\n", |
| 526 | i); |
| 527 | intel_idle_cpuidle_devices_uninit(); |
| 528 | return -EIO; |
| 529 | } |
| 530 | } |
| 531 | |
| 532 | return 0; |
| 533 | } |
| 534 | |
| 535 | |
| 536 | static int __init intel_idle_init(void) |
| 537 | { |
| 538 | int retval; |
| 539 | |
Thomas Renninger | d189604 | 2010-11-03 17:06:14 +0100 | [diff] [blame] | 540 | /* Do not load intel_idle at all for now if idle= is passed */ |
| 541 | if (boot_option_idle_override != IDLE_NO_OVERRIDE) |
| 542 | return -ENODEV; |
| 543 | |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 544 | retval = intel_idle_probe(); |
| 545 | if (retval) |
| 546 | return retval; |
| 547 | |
Deepthi Dharwar | 46bcfad | 2011-10-28 16:20:42 +0530 | [diff] [blame] | 548 | intel_idle_cpuidle_driver_init(); |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 549 | retval = cpuidle_register_driver(&intel_idle_driver); |
| 550 | if (retval) { |
| 551 | printk(KERN_DEBUG PREFIX "intel_idle yielding to %s", |
| 552 | cpuidle_get_driver()->name); |
| 553 | return retval; |
| 554 | } |
| 555 | |
| 556 | retval = intel_idle_cpuidle_devices_init(); |
| 557 | if (retval) { |
| 558 | cpuidle_unregister_driver(&intel_idle_driver); |
| 559 | return retval; |
| 560 | } |
| 561 | |
| 562 | return 0; |
| 563 | } |
| 564 | |
| 565 | static void __exit intel_idle_exit(void) |
| 566 | { |
| 567 | intel_idle_cpuidle_devices_uninit(); |
| 568 | cpuidle_unregister_driver(&intel_idle_driver); |
| 569 | |
Shaohua Li | 2a2d31c | 2011-01-10 09:38:12 +0800 | [diff] [blame] | 570 | if (lapic_timer_reliable_states != LAPIC_TIMER_ALWAYS_RELIABLE) { |
Shaohua Li | 39a74fd | 2012-01-10 15:48:19 -0800 | [diff] [blame] | 571 | on_each_cpu(__setup_broadcast_timer, (void *)false, 1); |
Shaohua Li | 2a2d31c | 2011-01-10 09:38:12 +0800 | [diff] [blame] | 572 | unregister_cpu_notifier(&setup_broadcast_notifier); |
| 573 | } |
| 574 | |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 575 | return; |
| 576 | } |
| 577 | |
| 578 | module_init(intel_idle_init); |
| 579 | module_exit(intel_idle_exit); |
| 580 | |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 581 | module_param(max_cstate, int, 0444); |
Len Brown | 2671717 | 2010-03-08 14:07:30 -0500 | [diff] [blame] | 582 | |
| 583 | MODULE_AUTHOR("Len Brown <len.brown@intel.com>"); |
| 584 | MODULE_DESCRIPTION("Cpuidle driver for Intel Hardware v" INTEL_IDLE_VERSION); |
| 585 | MODULE_LICENSE("GPL"); |