diff options
Diffstat (limited to 'drivers/acpi/processor_idle.c')
| -rw-r--r-- | drivers/acpi/processor_idle.c | 1437 |
1 files changed, 1437 insertions, 0 deletions
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c new file mode 100644 index 0000000000..55437f5e0c --- /dev/null +++ b/drivers/acpi/processor_idle.c @@ -0,0 +1,1437 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * processor_idle - idle state submodule to the ACPI processor driver + * + * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> + * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> + * Copyright (C) 2004, 2005 Dominik Brodowski <linux@brodo.de> + * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> + * - Added processor hotplug support + * Copyright (C) 2005 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> + * - Added support for C3 on SMP + */ +#define pr_fmt(fmt) "ACPI: " fmt + +#include <linux/module.h> +#include <linux/acpi.h> +#include <linux/dmi.h> +#include <linux/sched.h> /* need_resched() */ +#include <linux/sort.h> +#include <linux/tick.h> +#include <linux/cpuidle.h> +#include <linux/cpu.h> +#include <linux/minmax.h> +#include <linux/perf_event.h> +#include <acpi/processor.h> +#include <linux/context_tracking.h> + +/* + * Include the apic definitions for x86 to have the APIC timer related defines + * available also for UP (on SMP it gets magically included via linux/smp.h). + * asm/acpi.h is not an option, as it would require more include magic. Also + * creating an empty asm-ia64/apic.h would just trade pest vs. cholera. + */ +#ifdef CONFIG_X86 +#include <asm/apic.h> +#include <asm/cpu.h> +#endif + +#define ACPI_IDLE_STATE_START (IS_ENABLED(CONFIG_ARCH_HAS_CPU_RELAX) ? 1 : 0) + +static unsigned int max_cstate __read_mostly = ACPI_PROCESSOR_MAX_POWER; +module_param(max_cstate, uint, 0400); +static bool nocst __read_mostly; +module_param(nocst, bool, 0400); +static bool bm_check_disable __read_mostly; +module_param(bm_check_disable, bool, 0400); + +static unsigned int latency_factor __read_mostly = 2; +module_param(latency_factor, uint, 0644); + +static DEFINE_PER_CPU(struct cpuidle_device *, acpi_cpuidle_device); + +struct cpuidle_driver acpi_idle_driver = { + .name = "acpi_idle", + .owner = THIS_MODULE, +}; + +#ifdef CONFIG_ACPI_PROCESSOR_CSTATE +static +DEFINE_PER_CPU(struct acpi_processor_cx * [CPUIDLE_STATE_MAX], acpi_cstate); + +static int disabled_by_idle_boot_param(void) +{ + return boot_option_idle_override == IDLE_POLL || + boot_option_idle_override == IDLE_HALT; +} + +/* + * IBM ThinkPad R40e crashes mysteriously when going into C2 or C3. + * For now disable this. Probably a bug somewhere else. + * + * To skip this limit, boot/load with a large max_cstate limit. + */ +static int set_max_cstate(const struct dmi_system_id *id) +{ + if (max_cstate > ACPI_PROCESSOR_MAX_POWER) + return 0; + + pr_notice("%s detected - limiting to C%ld max_cstate." + " Override with \"processor.max_cstate=%d\"\n", id->ident, + (long)id->driver_data, ACPI_PROCESSOR_MAX_POWER + 1); + + max_cstate = (long)id->driver_data; + + return 0; +} + +static const struct dmi_system_id processor_power_dmi_table[] = { + { set_max_cstate, "Clevo 5600D", { + DMI_MATCH(DMI_BIOS_VENDOR,"Phoenix Technologies LTD"), + DMI_MATCH(DMI_BIOS_VERSION,"SHE845M0.86C.0013.D.0302131307")}, + (void *)2}, + { set_max_cstate, "Pavilion zv5000", { + DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), + DMI_MATCH(DMI_PRODUCT_NAME,"Pavilion zv5000 (DS502A#ABA)")}, + (void *)1}, + { set_max_cstate, "Asus L8400B", { + DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."), + DMI_MATCH(DMI_PRODUCT_NAME,"L8400B series Notebook PC")}, + (void *)1}, + {}, +}; + + +/* + * Callers should disable interrupts before the call and enable + * interrupts after return. + */ +static void __cpuidle acpi_safe_halt(void) +{ + if (!tif_need_resched()) { + raw_safe_halt(); + raw_local_irq_disable(); + } +} + +#ifdef ARCH_APICTIMER_STOPS_ON_C3 + +/* + * Some BIOS implementations switch to C3 in the published C2 state. + * This seems to be a common problem on AMD boxen, but other vendors + * are affected too. We pick the most conservative approach: we assume + * that the local APIC stops in both C2 and C3. + */ +static void lapic_timer_check_state(int state, struct acpi_processor *pr, + struct acpi_processor_cx *cx) +{ + struct acpi_processor_power *pwr = &pr->power; + u8 type = local_apic_timer_c2_ok ? ACPI_STATE_C3 : ACPI_STATE_C2; + + if (cpu_has(&cpu_data(pr->id), X86_FEATURE_ARAT)) + return; + + if (boot_cpu_has_bug(X86_BUG_AMD_APIC_C1E)) + type = ACPI_STATE_C1; + + /* + * Check, if one of the previous states already marked the lapic + * unstable + */ + if (pwr->timer_broadcast_on_state < state) + return; + + if (cx->type >= type) + pr->power.timer_broadcast_on_state = state; +} + +static void __lapic_timer_propagate_broadcast(void *arg) +{ + struct acpi_processor *pr = arg; + + if (pr->power.timer_broadcast_on_state < INT_MAX) + tick_broadcast_enable(); + else + tick_broadcast_disable(); +} + +static void lapic_timer_propagate_broadcast(struct acpi_processor *pr) +{ + smp_call_function_single(pr->id, __lapic_timer_propagate_broadcast, + (void *)pr, 1); +} + +/* Power(C) State timer broadcast control */ +static bool lapic_timer_needs_broadcast(struct acpi_processor *pr, + struct acpi_processor_cx *cx) +{ + return cx - pr->power.states >= pr->power.timer_broadcast_on_state; +} + +#else + +static void lapic_timer_check_state(int state, struct acpi_processor *pr, + struct acpi_processor_cx *cstate) { } +static void lapic_timer_propagate_broadcast(struct acpi_processor *pr) { } + +static bool lapic_timer_needs_broadcast(struct acpi_processor *pr, + struct acpi_processor_cx *cx) +{ + return false; +} + +#endif + +#if defined(CONFIG_X86) +static void tsc_check_state(int state) +{ + switch (boot_cpu_data.x86_vendor) { + case X86_VENDOR_HYGON: + case X86_VENDOR_AMD: + case X86_VENDOR_INTEL: + case X86_VENDOR_CENTAUR: + case X86_VENDOR_ZHAOXIN: + /* + * AMD Fam10h TSC will tick in all + * C/P/S0/S1 states when this bit is set. + */ + if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) + return; + fallthrough; + default: + /* TSC could halt in idle, so notify users */ + if (state > ACPI_STATE_C1) + mark_tsc_unstable("TSC halts in idle"); + } +} +#else +static void tsc_check_state(int state) { return; } +#endif + +static int acpi_processor_get_power_info_fadt(struct acpi_processor *pr) +{ + + if (!pr->pblk) + return -ENODEV; + + /* if info is obtained from pblk/fadt, type equals state */ + pr->power.states[ACPI_STATE_C2].type = ACPI_STATE_C2; + pr->power.states[ACPI_STATE_C3].type = ACPI_STATE_C3; + +#ifndef CONFIG_HOTPLUG_CPU + /* + * Check for P_LVL2_UP flag before entering C2 and above on + * an SMP system. + */ + if ((num_online_cpus() > 1) && + !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED)) + return -ENODEV; +#endif + + /* determine C2 and C3 address from pblk */ + pr->power.states[ACPI_STATE_C2].address = pr->pblk + 4; + pr->power.states[ACPI_STATE_C3].address = pr->pblk + 5; + + /* determine latencies from FADT */ + pr->power.states[ACPI_STATE_C2].latency = acpi_gbl_FADT.c2_latency; + pr->power.states[ACPI_STATE_C3].latency = acpi_gbl_FADT.c3_latency; + + /* + * FADT specified C2 latency must be less than or equal to + * 100 microseconds. + */ + if (acpi_gbl_FADT.c2_latency > ACPI_PROCESSOR_MAX_C2_LATENCY) { + acpi_handle_debug(pr->handle, "C2 latency too large [%d]\n", + acpi_gbl_FADT.c2_latency); + /* invalidate C2 */ + pr->power.states[ACPI_STATE_C2].address = 0; + } + + /* + * FADT supplied C3 latency must be less than or equal to + * 1000 microseconds. + */ + if (acpi_gbl_FADT.c3_latency > ACPI_PROCESSOR_MAX_C3_LATENCY) { + acpi_handle_debug(pr->handle, "C3 latency too large [%d]\n", + acpi_gbl_FADT.c3_latency); + /* invalidate C3 */ + pr->power.states[ACPI_STATE_C3].address = 0; + } + + acpi_handle_debug(pr->handle, "lvl2[0x%08x] lvl3[0x%08x]\n", + pr->power.states[ACPI_STATE_C2].address, + pr->power.states[ACPI_STATE_C3].address); + + snprintf(pr->power.states[ACPI_STATE_C2].desc, + ACPI_CX_DESC_LEN, "ACPI P_LVL2 IOPORT 0x%x", + pr->power.states[ACPI_STATE_C2].address); + snprintf(pr->power.states[ACPI_STATE_C3].desc, + ACPI_CX_DESC_LEN, "ACPI P_LVL3 IOPORT 0x%x", + pr->power.states[ACPI_STATE_C3].address); + + return 0; +} + +static int acpi_processor_get_power_info_default(struct acpi_processor *pr) +{ + if (!pr->power.states[ACPI_STATE_C1].valid) { + /* set the first C-State to C1 */ + /* all processors need to support C1 */ + pr->power.states[ACPI_STATE_C1].type = ACPI_STATE_C1; + pr->power.states[ACPI_STATE_C1].valid = 1; + pr->power.states[ACPI_STATE_C1].entry_method = ACPI_CSTATE_HALT; + + snprintf(pr->power.states[ACPI_STATE_C1].desc, + ACPI_CX_DESC_LEN, "ACPI HLT"); + } + /* the C0 state only exists as a filler in our array */ + pr->power.states[ACPI_STATE_C0].valid = 1; + return 0; +} + +static int acpi_processor_get_power_info_cst(struct acpi_processor *pr) +{ + int ret; + + if (nocst) + return -ENODEV; + + ret = acpi_processor_evaluate_cst(pr->handle, pr->id, &pr->power); + if (ret) + return ret; + + if (!pr->power.count) + return -EFAULT; + + pr->flags.has_cst = 1; + return 0; +} + +static void acpi_processor_power_verify_c3(struct acpi_processor *pr, + struct acpi_processor_cx *cx) +{ + static int bm_check_flag = -1; + static int bm_control_flag = -1; + + + if (!cx->address) + return; + + /* + * PIIX4 Erratum #18: We don't support C3 when Type-F (fast) + * DMA transfers are used by any ISA device to avoid livelock. + * Note that we could disable Type-F DMA (as recommended by + * the erratum), but this is known to disrupt certain ISA + * devices thus we take the conservative approach. + */ + if (errata.piix4.fdma) { + acpi_handle_debug(pr->handle, + "C3 not supported on PIIX4 with Type-F DMA\n"); + return; + } + + /* All the logic here assumes flags.bm_check is same across all CPUs */ + if (bm_check_flag == -1) { + /* Determine whether bm_check is needed based on CPU */ + acpi_processor_power_init_bm_check(&(pr->flags), pr->id); + bm_check_flag = pr->flags.bm_check; + bm_control_flag = pr->flags.bm_control; + } else { + pr->flags.bm_check = bm_check_flag; + pr->flags.bm_control = bm_control_flag; + } + + if (pr->flags.bm_check) { + if (!pr->flags.bm_control) { + if (pr->flags.has_cst != 1) { + /* bus mastering control is necessary */ + acpi_handle_debug(pr->handle, + "C3 support requires BM control\n"); + return; + } else { + /* Here we enter C3 without bus mastering */ + acpi_handle_debug(pr->handle, + "C3 support without BM control\n"); + } + } + } else { + /* + * WBINVD should be set in fadt, for C3 state to be + * supported on when bm_check is not required. + */ + if (!(acpi_gbl_FADT.flags & ACPI_FADT_WBINVD)) { + acpi_handle_debug(pr->handle, + "Cache invalidation should work properly" + " for C3 to be enabled on SMP systems\n"); + return; + } + } + + /* + * Otherwise we've met all of our C3 requirements. + * Normalize the C3 latency to expidite policy. Enable + * checking of bus mastering status (bm_check) so we can + * use this in our C3 policy + */ + cx->valid = 1; + + /* + * On older chipsets, BM_RLD needs to be set + * in order for Bus Master activity to wake the + * system from C3. Newer chipsets handle DMA + * during C3 automatically and BM_RLD is a NOP. + * In either case, the proper way to + * handle BM_RLD is to set it and leave it set. + */ + acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, 1); +} + +static int acpi_cst_latency_cmp(const void *a, const void *b) +{ + const struct acpi_processor_cx *x = a, *y = b; + + if (!(x->valid && y->valid)) + return 0; + if (x->latency > y->latency) + return 1; + if (x->latency < y->latency) + return -1; + return 0; +} +static void acpi_cst_latency_swap(void *a, void *b, int n) +{ + struct acpi_processor_cx *x = a, *y = b; + + if (!(x->valid && y->valid)) + return; + swap(x->latency, y->latency); +} + +static int acpi_processor_power_verify(struct acpi_processor *pr) +{ + unsigned int i; + unsigned int working = 0; + unsigned int last_latency = 0; + unsigned int last_type = 0; + bool buggy_latency = false; + + pr->power.timer_broadcast_on_state = INT_MAX; + + for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { + struct acpi_processor_cx *cx = &pr->power.states[i]; + + switch (cx->type) { + case ACPI_STATE_C1: + cx->valid = 1; + break; + + case ACPI_STATE_C2: + if (!cx->address) + break; + cx->valid = 1; + break; + + case ACPI_STATE_C3: + acpi_processor_power_verify_c3(pr, cx); + break; + } + if (!cx->valid) + continue; + if (cx->type >= last_type && cx->latency < last_latency) + buggy_latency = true; + last_latency = cx->latency; + last_type = cx->type; + + lapic_timer_check_state(i, pr, cx); + tsc_check_state(cx->type); + working++; + } + + if (buggy_latency) { + pr_notice("FW issue: working around C-state latencies out of order\n"); + sort(&pr->power.states[1], max_cstate, + sizeof(struct acpi_processor_cx), + acpi_cst_latency_cmp, + acpi_cst_latency_swap); + } + + lapic_timer_propagate_broadcast(pr); + + return working; +} + +static int acpi_processor_get_cstate_info(struct acpi_processor *pr) +{ + unsigned int i; + int result; + + + /* NOTE: the idle thread may not be running while calling + * this function */ + + /* Zero initialize all the C-states info. */ + memset(pr->power.states, 0, sizeof(pr->power.states)); + + result = acpi_processor_get_power_info_cst(pr); + if (result == -ENODEV) + result = acpi_processor_get_power_info_fadt(pr); + + if (result) + return result; + + acpi_processor_get_power_info_default(pr); + + pr->power.count = acpi_processor_power_verify(pr); + + /* + * if one state of type C2 or C3 is available, mark this + * CPU as being "idle manageable" + */ + for (i = 1; i < ACPI_PROCESSOR_MAX_POWER; i++) { + if (pr->power.states[i].valid) { + pr->power.count = i; + pr->flags.power = 1; + } + } + + return 0; +} + +/** + * acpi_idle_bm_check - checks if bus master activity was detected + */ +static int acpi_idle_bm_check(void) +{ + u32 bm_status = 0; + + if (bm_check_disable) + return 0; + + acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status); + if (bm_status) + acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, 1); + /* + * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect + * the true state of bus mastering activity; forcing us to + * manually check the BMIDEA bit of each IDE channel. + */ + else if (errata.piix4.bmisx) { + if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01) + || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01)) + bm_status = 1; + } + return bm_status; +} + +static __cpuidle void io_idle(unsigned long addr) +{ + /* IO port based C-state */ + inb(addr); + +#ifdef CONFIG_X86 + /* No delay is needed if we are in guest */ + if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) + return; + /* + * Modern (>=Nehalem) Intel systems use ACPI via intel_idle, + * not this code. Assume that any Intel systems using this + * are ancient and may need the dummy wait. This also assumes + * that the motivating chipset issue was Intel-only. + */ + if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL) + return; +#endif + /* + * Dummy wait op - must do something useless after P_LVL2 read + * because chipsets cannot guarantee that STPCLK# signal gets + * asserted in time to freeze execution properly + * + * This workaround has been in place since the original ACPI + * implementation was merged, circa 2002. + * + * If a profile is pointing to this instruction, please first + * consider moving your system to a more modern idle + * mechanism. + */ + inl(acpi_gbl_FADT.xpm_timer_block.address); +} + +/** + * acpi_idle_do_entry - enter idle state using the appropriate method + * @cx: cstate data + * + * Caller disables interrupt before call and enables interrupt after return. + */ +static void __cpuidle acpi_idle_do_entry(struct acpi_processor_cx *cx) +{ + perf_lopwr_cb(true); + + if (cx->entry_method == ACPI_CSTATE_FFH) { + /* Call into architectural FFH based C-state */ + acpi_processor_ffh_cstate_enter(cx); + } else if (cx->entry_method == ACPI_CSTATE_HALT) { + acpi_safe_halt(); + } else { + io_idle(cx->address); + } + + perf_lopwr_cb(false); +} + +/** + * acpi_idle_play_dead - enters an ACPI state for long-term idle (i.e. off-lining) + * @dev: the target CPU + * @index: the index of suggested state + */ +static int acpi_idle_play_dead(struct cpuidle_device *dev, int index) +{ + struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu); + + ACPI_FLUSH_CPU_CACHE(); + + while (1) { + + if (cx->entry_method == ACPI_CSTATE_HALT) + raw_safe_halt(); + else if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) { + io_idle(cx->address); + } else + return -ENODEV; + } + + /* Never reached */ + return 0; +} + +static __always_inline bool acpi_idle_fallback_to_c1(struct acpi_processor *pr) +{ + return IS_ENABLED(CONFIG_HOTPLUG_CPU) && !pr->flags.has_cst && + !(acpi_gbl_FADT.flags & ACPI_FADT_C2_MP_SUPPORTED); +} + +static int c3_cpu_count; +static DEFINE_RAW_SPINLOCK(c3_lock); + +/** + * acpi_idle_enter_bm - enters C3 with proper BM handling + * @drv: cpuidle driver + * @pr: Target processor + * @cx: Target state context + * @index: index of target state + */ +static int __cpuidle acpi_idle_enter_bm(struct cpuidle_driver *drv, + struct acpi_processor *pr, + struct acpi_processor_cx *cx, + int index) +{ + static struct acpi_processor_cx safe_cx = { + .entry_method = ACPI_CSTATE_HALT, + }; + + /* + * disable bus master + * bm_check implies we need ARB_DIS + * bm_control implies whether we can do ARB_DIS + * + * That leaves a case where bm_check is set and bm_control is not set. + * In that case we cannot do much, we enter C3 without doing anything. + */ + bool dis_bm = pr->flags.bm_control; + + instrumentation_begin(); + + /* If we can skip BM, demote to a safe state. */ + if (!cx->bm_sts_skip && acpi_idle_bm_check()) { + dis_bm = false; + index = drv->safe_state_index; + if (index >= 0) { + cx = this_cpu_read(acpi_cstate[index]); + } else { + cx = &safe_cx; + index = -EBUSY; + } + } + + if (dis_bm) { + raw_spin_lock(&c3_lock); + c3_cpu_count++; + /* Disable bus master arbitration when all CPUs are in C3 */ + if (c3_cpu_count == num_online_cpus()) + acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1); + raw_spin_unlock(&c3_lock); + } + + ct_cpuidle_enter(); + + acpi_idle_do_entry(cx); + + ct_cpuidle_exit(); + + /* Re-enable bus master arbitration */ + if (dis_bm) { + raw_spin_lock(&c3_lock); + acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0); + c3_cpu_count--; + raw_spin_unlock(&c3_lock); + } + + instrumentation_end(); + + return index; +} + +static int __cpuidle acpi_idle_enter(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu); + struct acpi_processor *pr; + + pr = __this_cpu_read(processors); + if (unlikely(!pr)) + return -EINVAL; + + if (cx->type != ACPI_STATE_C1) { + if (cx->type == ACPI_STATE_C3 && pr->flags.bm_check) + return acpi_idle_enter_bm(drv, pr, cx, index); + + /* C2 to C1 demotion. */ + if (acpi_idle_fallback_to_c1(pr) && num_online_cpus() > 1) { + index = ACPI_IDLE_STATE_START; + cx = per_cpu(acpi_cstate[index], dev->cpu); + } + } + + if (cx->type == ACPI_STATE_C3) + ACPI_FLUSH_CPU_CACHE(); + + acpi_idle_do_entry(cx); + + return index; +} + +static int __cpuidle acpi_idle_enter_s2idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + struct acpi_processor_cx *cx = per_cpu(acpi_cstate[index], dev->cpu); + + if (cx->type == ACPI_STATE_C3) { + struct acpi_processor *pr = __this_cpu_read(processors); + + if (unlikely(!pr)) + return 0; + + if (pr->flags.bm_check) { + u8 bm_sts_skip = cx->bm_sts_skip; + + /* Don't check BM_STS, do an unconditional ARB_DIS for S2IDLE */ + cx->bm_sts_skip = 1; + acpi_idle_enter_bm(drv, pr, cx, index); + cx->bm_sts_skip = bm_sts_skip; + + return 0; + } else { + ACPI_FLUSH_CPU_CACHE(); + } + } + acpi_idle_do_entry(cx); + + return 0; +} + +static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr, + struct cpuidle_device *dev) +{ + int i, count = ACPI_IDLE_STATE_START; + struct acpi_processor_cx *cx; + struct cpuidle_state *state; + + if (max_cstate == 0) + max_cstate = 1; + + for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { + state = &acpi_idle_driver.states[count]; + cx = &pr->power.states[i]; + + if (!cx->valid) + continue; + + per_cpu(acpi_cstate[count], dev->cpu) = cx; + + if (lapic_timer_needs_broadcast(pr, cx)) + state->flags |= CPUIDLE_FLAG_TIMER_STOP; + + if (cx->type == ACPI_STATE_C3) { + state->flags |= CPUIDLE_FLAG_TLB_FLUSHED; + if (pr->flags.bm_check) + state->flags |= CPUIDLE_FLAG_RCU_IDLE; + } + + count++; + if (count == CPUIDLE_STATE_MAX) + break; + } + + if (!count) + return -EINVAL; + + return 0; +} + +static int acpi_processor_setup_cstates(struct acpi_processor *pr) +{ + int i, count; + struct acpi_processor_cx *cx; + struct cpuidle_state *state; + struct cpuidle_driver *drv = &acpi_idle_driver; + + if (max_cstate == 0) + max_cstate = 1; + + if (IS_ENABLED(CONFIG_ARCH_HAS_CPU_RELAX)) { + cpuidle_poll_state_init(drv); + count = 1; + } else { + count = 0; + } + + for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) { + cx = &pr->power.states[i]; + + if (!cx->valid) + continue; + + state = &drv->states[count]; + snprintf(state->name, CPUIDLE_NAME_LEN, "C%d", i); + strscpy(state->desc, cx->desc, CPUIDLE_DESC_LEN); + state->exit_latency = cx->latency; + state->target_residency = cx->latency * latency_factor; + state->enter = acpi_idle_enter; + + state->flags = 0; + if (cx->type == ACPI_STATE_C1 || cx->type == ACPI_STATE_C2 || + cx->type == ACPI_STATE_C3) { + state->enter_dead = acpi_idle_play_dead; + if (cx->type != ACPI_STATE_C3) + drv->safe_state_index = count; + } + /* + * Halt-induced C1 is not good for ->enter_s2idle, because it + * re-enables interrupts on exit. Moreover, C1 is generally not + * particularly interesting from the suspend-to-idle angle, so + * avoid C1 and the situations in which we may need to fall back + * to it altogether. + */ + if (cx->type != ACPI_STATE_C1 && !acpi_idle_fallback_to_c1(pr)) + state->enter_s2idle = acpi_idle_enter_s2idle; + + count++; + if (count == CPUIDLE_STATE_MAX) + break; + } + + drv->state_count = count; + + if (!count) + return -EINVAL; + + return 0; +} + +static inline void acpi_processor_cstate_first_run_checks(void) +{ + static int first_run; + + if (first_run) + return; + dmi_check_system(processor_power_dmi_table); + max_cstate = acpi_processor_cstate_check(max_cstate); + if (max_cstate < ACPI_C_STATES_MAX) + pr_notice("processor limited to max C-state %d\n", max_cstate); + + first_run++; + + if (nocst) + return; + + acpi_processor_claim_cst_control(); +} +#else + +static inline int disabled_by_idle_boot_param(void) { return 0; } +static inline void acpi_processor_cstate_first_run_checks(void) { } +static int acpi_processor_get_cstate_info(struct acpi_processor *pr) +{ + return -ENODEV; +} + +static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr, + struct cpuidle_device *dev) +{ + return -EINVAL; +} + +static int acpi_processor_setup_cstates(struct acpi_processor *pr) +{ + return -EINVAL; +} + +#endif /* CONFIG_ACPI_PROCESSOR_CSTATE */ + +struct acpi_lpi_states_array { + unsigned int size; + unsigned int composite_states_size; + struct acpi_lpi_state *entries; + struct acpi_lpi_state *composite_states[ACPI_PROCESSOR_MAX_POWER]; +}; + +static int obj_get_integer(union acpi_object *obj, u32 *value) +{ + if (obj->type != ACPI_TYPE_INTEGER) + return -EINVAL; + + *value = obj->integer.value; + return 0; +} + +static int acpi_processor_evaluate_lpi(acpi_handle handle, + struct acpi_lpi_states_array *info) +{ + acpi_status status; + int ret = 0; + int pkg_count, state_idx = 1, loop; + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + union acpi_object *lpi_data; + struct acpi_lpi_state *lpi_state; + + status = acpi_evaluate_object(handle, "_LPI", NULL, &buffer); + if (ACPI_FAILURE(status)) { + acpi_handle_debug(handle, "No _LPI, giving up\n"); + return -ENODEV; + } + + lpi_data = buffer.pointer; + + /* There must be at least 4 elements = 3 elements + 1 package */ + if (!lpi_data || lpi_data->type != ACPI_TYPE_PACKAGE || + lpi_data->package.count < 4) { + pr_debug("not enough elements in _LPI\n"); + ret = -ENODATA; + goto end; + } + + pkg_count = lpi_data->package.elements[2].integer.value; + + /* Validate number of power states. */ + if (pkg_count < 1 || pkg_count != lpi_data->package.count - 3) { + pr_debug("count given by _LPI is not valid\n"); + ret = -ENODATA; + goto end; + } + + lpi_state = kcalloc(pkg_count, sizeof(*lpi_state), GFP_KERNEL); + if (!lpi_state) { + ret = -ENOMEM; + goto end; + } + + info->size = pkg_count; + info->entries = lpi_state; + + /* LPI States start at index 3 */ + for (loop = 3; state_idx <= pkg_count; loop++, state_idx++, lpi_state++) { + union acpi_object *element, *pkg_elem, *obj; + + element = &lpi_data->package.elements[loop]; + if (element->type != ACPI_TYPE_PACKAGE || element->package.count < 7) + continue; + + pkg_elem = element->package.elements; + + obj = pkg_elem + 6; + if (obj->type == ACPI_TYPE_BUFFER) { + struct acpi_power_register *reg; + + reg = (struct acpi_power_register *)obj->buffer.pointer; + if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO && + reg->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE) + continue; + + lpi_state->address = reg->address; + lpi_state->entry_method = + reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE ? + ACPI_CSTATE_FFH : ACPI_CSTATE_SYSTEMIO; + } else if (obj->type == ACPI_TYPE_INTEGER) { + lpi_state->entry_method = ACPI_CSTATE_INTEGER; + lpi_state->address = obj->integer.value; + } else { + continue; + } + + /* elements[7,8] skipped for now i.e. Residency/Usage counter*/ + + obj = pkg_elem + 9; + if (obj->type == ACPI_TYPE_STRING) + strscpy(lpi_state->desc, obj->string.pointer, + ACPI_CX_DESC_LEN); + + lpi_state->index = state_idx; + if (obj_get_integer(pkg_elem + 0, &lpi_state->min_residency)) { + pr_debug("No min. residency found, assuming 10 us\n"); + lpi_state->min_residency = 10; + } + + if (obj_get_integer(pkg_elem + 1, &lpi_state->wake_latency)) { + pr_debug("No wakeup residency found, assuming 10 us\n"); + lpi_state->wake_latency = 10; + } + + if (obj_get_integer(pkg_elem + 2, &lpi_state->flags)) + lpi_state->flags = 0; + + if (obj_get_integer(pkg_elem + 3, &lpi_state->arch_flags)) + lpi_state->arch_flags = 0; + + if (obj_get_integer(pkg_elem + 4, &lpi_state->res_cnt_freq)) + lpi_state->res_cnt_freq = 1; + + if (obj_get_integer(pkg_elem + 5, &lpi_state->enable_parent_state)) + lpi_state->enable_parent_state = 0; + } + + acpi_handle_debug(handle, "Found %d power states\n", state_idx); +end: + kfree(buffer.pointer); + return ret; +} + +/* + * flat_state_cnt - the number of composite LPI states after the process of flattening + */ +static int flat_state_cnt; + +/** + * combine_lpi_states - combine local and parent LPI states to form a composite LPI state + * + * @local: local LPI state + * @parent: parent LPI state + * @result: composite LPI state + */ +static bool combine_lpi_states(struct acpi_lpi_state *local, + struct acpi_lpi_state *parent, + struct acpi_lpi_state *result) +{ + if (parent->entry_method == ACPI_CSTATE_INTEGER) { + if (!parent->address) /* 0 means autopromotable */ + return false; + result->address = local->address + parent->address; + } else { + result->address = parent->address; + } + + result->min_residency = max(local->min_residency, parent->min_residency); + result->wake_latency = local->wake_latency + parent->wake_latency; + result->enable_parent_state = parent->enable_parent_state; + result->entry_method = local->entry_method; + + result->flags = parent->flags; + result->arch_flags = parent->arch_flags; + result->index = parent->index; + + strscpy(result->desc, local->desc, ACPI_CX_DESC_LEN); + strlcat(result->desc, "+", ACPI_CX_DESC_LEN); + strlcat(result->desc, parent->desc, ACPI_CX_DESC_LEN); + return true; +} + +#define ACPI_LPI_STATE_FLAGS_ENABLED BIT(0) + +static void stash_composite_state(struct acpi_lpi_states_array *curr_level, + struct acpi_lpi_state *t) +{ + curr_level->composite_states[curr_level->composite_states_size++] = t; +} + +static int flatten_lpi_states(struct acpi_processor *pr, + struct acpi_lpi_states_array *curr_level, + struct acpi_lpi_states_array *prev_level) +{ + int i, j, state_count = curr_level->size; + struct acpi_lpi_state *p, *t = curr_level->entries; + + curr_level->composite_states_size = 0; + for (j = 0; j < state_count; j++, t++) { + struct acpi_lpi_state *flpi; + + if (!(t->flags & ACPI_LPI_STATE_FLAGS_ENABLED)) + continue; + + if (flat_state_cnt >= ACPI_PROCESSOR_MAX_POWER) { + pr_warn("Limiting number of LPI states to max (%d)\n", + ACPI_PROCESSOR_MAX_POWER); + pr_warn("Please increase ACPI_PROCESSOR_MAX_POWER if needed.\n"); + break; + } + + flpi = &pr->power.lpi_states[flat_state_cnt]; + + if (!prev_level) { /* leaf/processor node */ + memcpy(flpi, t, sizeof(*t)); + stash_composite_state(curr_level, flpi); + flat_state_cnt++; + continue; + } + + for (i = 0; i < prev_level->composite_states_size; i++) { + p = prev_level->composite_states[i]; + if (t->index <= p->enable_parent_state && + combine_lpi_states(p, t, flpi)) { + stash_composite_state(curr_level, flpi); + flat_state_cnt++; + flpi++; + } + } + } + + kfree(curr_level->entries); + return 0; +} + +int __weak acpi_processor_ffh_lpi_probe(unsigned int cpu) +{ + return -EOPNOTSUPP; +} + +static int acpi_processor_get_lpi_info(struct acpi_processor *pr) +{ + int ret, i; + acpi_status status; + acpi_handle handle = pr->handle, pr_ahandle; + struct acpi_device *d = NULL; + struct acpi_lpi_states_array info[2], *tmp, *prev, *curr; + + /* make sure our architecture has support */ + ret = acpi_processor_ffh_lpi_probe(pr->id); + if (ret == -EOPNOTSUPP) + return ret; + + if (!osc_pc_lpi_support_confirmed) + return -EOPNOTSUPP; + + if (!acpi_has_method(handle, "_LPI")) + return -EINVAL; + + flat_state_cnt = 0; + prev = &info[0]; + curr = &info[1]; + handle = pr->handle; + ret = acpi_processor_evaluate_lpi(handle, prev); + if (ret) + return ret; + flatten_lpi_states(pr, prev, NULL); + + status = acpi_get_parent(handle, &pr_ahandle); + while (ACPI_SUCCESS(status)) { + d = acpi_fetch_acpi_dev(pr_ahandle); + if (!d) + break; + + handle = pr_ahandle; + + if (strcmp(acpi_device_hid(d), ACPI_PROCESSOR_CONTAINER_HID)) + break; + + /* can be optional ? */ + if (!acpi_has_method(handle, "_LPI")) + break; + + ret = acpi_processor_evaluate_lpi(handle, curr); + if (ret) + break; + + /* flatten all the LPI states in this level of hierarchy */ + flatten_lpi_states(pr, curr, prev); + + tmp = prev, prev = curr, curr = tmp; + + status = acpi_get_parent(handle, &pr_ahandle); + } + + pr->power.count = flat_state_cnt; + /* reset the index after flattening */ + for (i = 0; i < pr->power.count; i++) + pr->power.lpi_states[i].index = i; + + /* Tell driver that _LPI is supported. */ + pr->flags.has_lpi = 1; + pr->flags.power = 1; + + return 0; +} + +int __weak acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi) +{ + return -ENODEV; +} + +/** + * acpi_idle_lpi_enter - enters an ACPI any LPI state + * @dev: the target CPU + * @drv: cpuidle driver containing cpuidle state info + * @index: index of target state + * + * Return: 0 for success or negative value for error + */ +static int acpi_idle_lpi_enter(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + struct acpi_processor *pr; + struct acpi_lpi_state *lpi; + + pr = __this_cpu_read(processors); + + if (unlikely(!pr)) + return -EINVAL; + + lpi = &pr->power.lpi_states[index]; + if (lpi->entry_method == ACPI_CSTATE_FFH) + return acpi_processor_ffh_lpi_enter(lpi); + + return -EINVAL; +} + +static int acpi_processor_setup_lpi_states(struct acpi_processor *pr) +{ + int i; + struct acpi_lpi_state *lpi; + struct cpuidle_state *state; + struct cpuidle_driver *drv = &acpi_idle_driver; + + if (!pr->flags.has_lpi) + return -EOPNOTSUPP; + + for (i = 0; i < pr->power.count && i < CPUIDLE_STATE_MAX; i++) { + lpi = &pr->power.lpi_states[i]; + + state = &drv->states[i]; + snprintf(state->name, CPUIDLE_NAME_LEN, "LPI-%d", i); + strscpy(state->desc, lpi->desc, CPUIDLE_DESC_LEN); + state->exit_latency = lpi->wake_latency; + state->target_residency = lpi->min_residency; + state->flags |= arch_get_idle_state_flags(lpi->arch_flags); + if (i != 0 && lpi->entry_method == ACPI_CSTATE_FFH) + state->flags |= CPUIDLE_FLAG_RCU_IDLE; + state->enter = acpi_idle_lpi_enter; + drv->safe_state_index = i; + } + + drv->state_count = i; + + return 0; +} + +/** + * acpi_processor_setup_cpuidle_states- prepares and configures cpuidle + * global state data i.e. idle routines + * + * @pr: the ACPI processor + */ +static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr) +{ + int i; + struct cpuidle_driver *drv = &acpi_idle_driver; + + if (!pr->flags.power_setup_done || !pr->flags.power) + return -EINVAL; + + drv->safe_state_index = -1; + for (i = ACPI_IDLE_STATE_START; i < CPUIDLE_STATE_MAX; i++) { + drv->states[i].name[0] = '\0'; + drv->states[i].desc[0] = '\0'; + } + + if (pr->flags.has_lpi) + return acpi_processor_setup_lpi_states(pr); + + return acpi_processor_setup_cstates(pr); +} + +/** + * acpi_processor_setup_cpuidle_dev - prepares and configures CPUIDLE + * device i.e. per-cpu data + * + * @pr: the ACPI processor + * @dev : the cpuidle device + */ +static int acpi_processor_setup_cpuidle_dev(struct acpi_processor *pr, + struct cpuidle_device *dev) +{ + if (!pr->flags.power_setup_done || !pr->flags.power || !dev) + return -EINVAL; + + dev->cpu = pr->id; + if (pr->flags.has_lpi) + return acpi_processor_ffh_lpi_probe(pr->id); + + return acpi_processor_setup_cpuidle_cx(pr, dev); +} + +static int acpi_processor_get_power_info(struct acpi_processor *pr) +{ + int ret; + + ret = acpi_processor_get_lpi_info(pr); + if (ret) + ret = acpi_processor_get_cstate_info(pr); + + return ret; +} + +int acpi_processor_hotplug(struct acpi_processor *pr) +{ + int ret = 0; + struct cpuidle_device *dev; + + if (disabled_by_idle_boot_param()) + return 0; + + if (!pr->flags.power_setup_done) + return -ENODEV; + + dev = per_cpu(acpi_cpuidle_device, pr->id); + cpuidle_pause_and_lock(); + cpuidle_disable_device(dev); + ret = acpi_processor_get_power_info(pr); + if (!ret && pr->flags.power) { + acpi_processor_setup_cpuidle_dev(pr, dev); + ret = cpuidle_enable_device(dev); + } + cpuidle_resume_and_unlock(); + + return ret; +} + +int acpi_processor_power_state_has_changed(struct acpi_processor *pr) +{ + int cpu; + struct acpi_processor *_pr; + struct cpuidle_device *dev; + + if (disabled_by_idle_boot_param()) + return 0; + + if (!pr->flags.power_setup_done) + return -ENODEV; + + /* + * FIXME: Design the ACPI notification to make it once per + * system instead of once per-cpu. This condition is a hack + * to make the code that updates C-States be called once. + */ + + if (pr->id == 0 && cpuidle_get_driver() == &acpi_idle_driver) { + + /* Protect against cpu-hotplug */ + cpus_read_lock(); + cpuidle_pause_and_lock(); + + /* Disable all cpuidle devices */ + for_each_online_cpu(cpu) { + _pr = per_cpu(processors, cpu); + if (!_pr || !_pr->flags.power_setup_done) + continue; + dev = per_cpu(acpi_cpuidle_device, cpu); + cpuidle_disable_device(dev); + } + + /* Populate Updated C-state information */ + acpi_processor_get_power_info(pr); + acpi_processor_setup_cpuidle_states(pr); + + /* Enable all cpuidle devices */ + for_each_online_cpu(cpu) { + _pr = per_cpu(processors, cpu); + if (!_pr || !_pr->flags.power_setup_done) + continue; + acpi_processor_get_power_info(_pr); + if (_pr->flags.power) { + dev = per_cpu(acpi_cpuidle_device, cpu); + acpi_processor_setup_cpuidle_dev(_pr, dev); + cpuidle_enable_device(dev); + } + } + cpuidle_resume_and_unlock(); + cpus_read_unlock(); + } + + return 0; +} + +static int acpi_processor_registered; + +int acpi_processor_power_init(struct acpi_processor *pr) +{ + int retval; + struct cpuidle_device *dev; + + if (disabled_by_idle_boot_param()) + return 0; + + acpi_processor_cstate_first_run_checks(); + + if (!acpi_processor_get_power_info(pr)) + pr->flags.power_setup_done = 1; + + /* + * Install the idle handler if processor power management is supported. + * Note that we use previously set idle handler will be used on + * platforms that only support C1. + */ + if (pr->flags.power) { + /* Register acpi_idle_driver if not already registered */ + if (!acpi_processor_registered) { + acpi_processor_setup_cpuidle_states(pr); + retval = cpuidle_register_driver(&acpi_idle_driver); + if (retval) + return retval; + pr_debug("%s registered with cpuidle\n", + acpi_idle_driver.name); + } + + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (!dev) + return -ENOMEM; + per_cpu(acpi_cpuidle_device, pr->id) = dev; + + acpi_processor_setup_cpuidle_dev(pr, dev); + + /* Register per-cpu cpuidle_device. Cpuidle driver + * must already be registered before registering device + */ + retval = cpuidle_register_device(dev); + if (retval) { + if (acpi_processor_registered == 0) + cpuidle_unregister_driver(&acpi_idle_driver); + return retval; + } + acpi_processor_registered++; + } + return 0; +} + +int acpi_processor_power_exit(struct acpi_processor *pr) +{ + struct cpuidle_device *dev = per_cpu(acpi_cpuidle_device, pr->id); + + if (disabled_by_idle_boot_param()) + return 0; + + if (pr->flags.power) { + cpuidle_unregister_device(dev); + acpi_processor_registered--; + if (acpi_processor_registered == 0) + cpuidle_unregister_driver(&acpi_idle_driver); + } + + pr->flags.power_setup_done = 0; + return 0; +} |