/* * Copyright (c) 2013-2015, ARM Limited and Contributors. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * Neither the name of ARM nor the names of its contributors may be used * to endorse or promote products derived from this software without specific * prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include #include #include #include #include #include #include #include #include #include #include #include /* generic_timer_backup() */ #include #include #include #include #include #include #include #include #if !ENABLE_PLAT_COMPAT #define MTK_PWR_LVL0 0 #define MTK_PWR_LVL1 1 #define MTK_PWR_LVL2 2 /* Macros to read the MTK power domain state */ #define MTK_CORE_PWR_STATE(state) (state)->pwr_domain_state[MTK_PWR_LVL0] #define MTK_CLUSTER_PWR_STATE(state) (state)->pwr_domain_state[MTK_PWR_LVL1] #define MTK_SYSTEM_PWR_STATE(state) ((PLAT_MAX_PWR_LVL > MTK_PWR_LVL1) ?\ (state)->pwr_domain_state[MTK_PWR_LVL2] : 0) #endif struct core_context { unsigned long timer_data[8]; unsigned int count; unsigned int rst; unsigned int abt; unsigned int brk; }; struct cluster_context { struct core_context core[PLATFORM_MAX_CPUS_PER_CLUSTER]; }; /* * Top level structure to hold the complete context of a multi cluster system */ struct system_context { struct cluster_context cluster[PLATFORM_CLUSTER_COUNT]; }; /* * Top level structure which encapsulates the context of the entire system */ static struct system_context dormant_data[1]; static inline struct cluster_context *system_cluster( struct system_context *system, uint32_t clusterid) { return &system->cluster[clusterid]; } static inline struct core_context *cluster_core(struct cluster_context *cluster, uint32_t cpuid) { return &cluster->core[cpuid]; } static struct cluster_context *get_cluster_data(unsigned long mpidr) { uint32_t clusterid; clusterid = (mpidr & MPIDR_CLUSTER_MASK) >> MPIDR_AFFINITY_BITS; return system_cluster(dormant_data, clusterid); } static struct core_context *get_core_data(unsigned long mpidr) { struct cluster_context *cluster; uint32_t cpuid; cluster = get_cluster_data(mpidr); cpuid = mpidr & MPIDR_CPU_MASK; return cluster_core(cluster, cpuid); } static void mt_save_generic_timer(unsigned long *container) { uint64_t ctl; uint64_t val; __asm__ volatile("mrs %x0, cntkctl_el1\n\t" "mrs %x1, cntp_cval_el0\n\t" "stp %x0, %x1, [%2, #0]" : "=&r" (ctl), "=&r" (val) : "r" (container) : "memory"); __asm__ volatile("mrs %x0, cntp_tval_el0\n\t" "mrs %x1, cntp_ctl_el0\n\t" "stp %x0, %x1, [%2, #16]" : "=&r" (val), "=&r" (ctl) : "r" (container) : "memory"); __asm__ volatile("mrs %x0, cntv_tval_el0\n\t" "mrs %x1, cntv_ctl_el0\n\t" "stp %x0, %x1, [%2, #32]" : "=&r" (val), "=&r" (ctl) : "r" (container) : "memory"); } static void mt_restore_generic_timer(unsigned long *container) { uint64_t ctl; uint64_t val; __asm__ volatile("ldp %x0, %x1, [%2, #0]\n\t" "msr cntkctl_el1, %x0\n\t" "msr cntp_cval_el0, %x1" : "=&r" (ctl), "=&r" (val) : "r" (container) : "memory"); __asm__ volatile("ldp %x0, %x1, [%2, #16]\n\t" "msr cntp_tval_el0, %x0\n\t" "msr cntp_ctl_el0, %x1" : "=&r" (val), "=&r" (ctl) : "r" (container) : "memory"); __asm__ volatile("ldp %x0, %x1, [%2, #32]\n\t" "msr cntv_tval_el0, %x0\n\t" "msr cntv_ctl_el0, %x1" : "=&r" (val), "=&r" (ctl) : "r" (container) : "memory"); } static inline uint64_t read_cntpctl(void) { uint64_t cntpctl; __asm__ volatile("mrs %x0, cntp_ctl_el0" : "=r" (cntpctl) : : "memory"); return cntpctl; } static inline void write_cntpctl(uint64_t cntpctl) { __asm__ volatile("msr cntp_ctl_el0, %x0" : : "r"(cntpctl)); } static void stop_generic_timer(void) { /* * Disable the timer and mask the irq to prevent * suprious interrupts on this cpu interface. It * will bite us when we come back if we don't. It * will be replayed on the inbound cluster. */ uint64_t cntpctl = read_cntpctl(); write_cntpctl(clr_cntp_ctl_enable(cntpctl)); } static void mt_cpu_save(unsigned long mpidr) { struct core_context *core; core = get_core_data(mpidr); mt_save_generic_timer(core->timer_data); /* disable timer irq, and upper layer should enable it again. */ stop_generic_timer(); } static void mt_cpu_restore(unsigned long mpidr) { struct core_context *core; core = get_core_data(mpidr); mt_restore_generic_timer(core->timer_data); } static void mt_platform_save_context(unsigned long mpidr) { /* mcusys_save_context: */ mt_cpu_save(mpidr); } static void mt_platform_restore_context(unsigned long mpidr) { /* mcusys_restore_context: */ mt_cpu_restore(mpidr); } #if ENABLE_PLAT_COMPAT /******************************************************************************* * Private function which is used to determine if any platform actions * should be performed for the specified affinity instance given its * state. Nothing needs to be done if the 'state' is not off or if this is not * the highest affinity level which will enter the 'state'. *******************************************************************************/ static int32_t plat_do_plat_actions(unsigned int afflvl, unsigned int state) { unsigned int max_phys_off_afflvl; assert(afflvl <= MPIDR_AFFLVL2); if (state != PSCI_STATE_OFF) return -EAGAIN; /* * Find the highest affinity level which will be suspended and postpone * all the platform specific actions until that level is hit. */ max_phys_off_afflvl = psci_get_max_phys_off_afflvl(); assert(max_phys_off_afflvl != PSCI_INVALID_DATA); if (afflvl != max_phys_off_afflvl) return -EAGAIN; return 0; } /******************************************************************************* * MTK_platform handler called when an affinity instance is about to enter * standby. ******************************************************************************/ static void plat_affinst_standby(unsigned int power_state) { unsigned int target_afflvl; /* Sanity check the requested state */ target_afflvl = psci_get_pstate_afflvl(power_state); /* * It's possible to enter standby only on affinity level 0 i.e. a cpu * on the MTK_platform. Ignore any other affinity level. */ if (target_afflvl == MPIDR_AFFLVL0) { /* * Enter standby state. dsb is good practice before using wfi * to enter low power states. */ dsb(); wfi(); } } #else static void plat_cpu_standby(plat_local_state_t cpu_state) { unsigned int scr; scr = read_scr_el3(); write_scr_el3(scr | SCR_IRQ_BIT); isb(); dsb(); wfi(); write_scr_el3(scr); } #endif /******************************************************************************* * MTK_platform handler called when an affinity instance is about to be turned * on. The level and mpidr determine the affinity instance. ******************************************************************************/ #if ENABLE_PLAT_COMPAT static int plat_affinst_on(unsigned long mpidr, unsigned long sec_entrypoint, unsigned int afflvl, unsigned int state) { int rc = PSCI_E_SUCCESS; unsigned long cpu_id; unsigned long cluster_id; uintptr_t rv; /* * It's possible to turn on only affinity level 0 i.e. a cpu * on the MTK_platform. Ignore any other affinity level. */ if (afflvl != MPIDR_AFFLVL0) return rc; cpu_id = mpidr & MPIDR_CPU_MASK; cluster_id = mpidr & MPIDR_CLUSTER_MASK; if (cluster_id) rv = (uintptr_t)&mt8173_mcucfg->mp1_rv_addr[cpu_id].rv_addr_lw; else rv = (uintptr_t)&mt8173_mcucfg->mp0_rv_addr[cpu_id].rv_addr_lw; mmio_write_32(rv, sec_entrypoint); INFO("mt_on[%ld:%ld], entry %x\n", cluster_id, cpu_id, mmio_read_32(rv)); spm_hotplug_on(mpidr); return rc; } #else static uintptr_t secure_entrypoint; static int plat_power_domain_on(unsigned long mpidr) { int rc = PSCI_E_SUCCESS; unsigned long cpu_id; unsigned long cluster_id; uintptr_t rv; cpu_id = mpidr & MPIDR_CPU_MASK; cluster_id = mpidr & MPIDR_CLUSTER_MASK; if (cluster_id) rv = (uintptr_t)&mt8173_mcucfg->mp1_rv_addr[cpu_id].rv_addr_lw; else rv = (uintptr_t)&mt8173_mcucfg->mp0_rv_addr[cpu_id].rv_addr_lw; mmio_write_32(rv, secure_entrypoint); INFO("mt_on[%ld:%ld], entry %x\n", cluster_id, cpu_id, mmio_read_32(rv)); spm_hotplug_on(mpidr); return rc; } #endif /******************************************************************************* * MTK_platform handler called when an affinity instance is about to be turned * off. The level and mpidr determine the affinity instance. The 'state' arg. * allows the platform to decide whether the cluster is being turned off and * take apt actions. * * CAUTION: This function is called with coherent stacks so that caches can be * turned off, flushed and coherency disabled. There is no guarantee that caches * will remain turned on across calls to this function as each affinity level is * dealt with. So do not write & read global variables across calls. It will be * wise to do flush a write to the global to prevent unpredictable results. ******************************************************************************/ #if ENABLE_PLAT_COMPAT static void plat_affinst_off(unsigned int afflvl, unsigned int state) { unsigned long mpidr = read_mpidr_el1(); /* Determine if any platform actions need to be executed. */ if (plat_do_plat_actions(afflvl, state) == -EAGAIN) return; /* Prevent interrupts from spuriously waking up this cpu */ arm_gic_cpuif_deactivate(); spm_hotplug_off(mpidr); trace_power_flow(mpidr, CPU_DOWN); if (afflvl != MPIDR_AFFLVL0) { /* Disable coherency if this cluster is to be turned off */ plat_cci_disable(); trace_power_flow(mpidr, CLUSTER_DOWN); } } #else static void plat_power_domain_off(const psci_power_state_t *state) { unsigned long mpidr = read_mpidr_el1(); /* Prevent interrupts from spuriously waking up this cpu */ arm_gic_cpuif_deactivate(); spm_hotplug_off(mpidr); trace_power_flow(mpidr, CPU_DOWN); if (MTK_CLUSTER_PWR_STATE(state) == MTK_LOCAL_STATE_OFF) { /* Disable coherency if this cluster is to be turned off */ plat_cci_disable(); trace_power_flow(mpidr, CLUSTER_DOWN); } } #endif /******************************************************************************* * MTK_platform handler called when an affinity instance is about to be * suspended. The level and mpidr determine the affinity instance. The 'state' * arg. allows the platform to decide whether the cluster is being turned off * and take apt actions. * * CAUTION: This function is called with coherent stacks so that caches can be * turned off, flushed and coherency disabled. There is no guarantee that caches * will remain turned on across calls to this function as each affinity level is * dealt with. So do not write & read global variables across calls. It will be * wise to do flush a write to the global to prevent unpredictable results. ******************************************************************************/ #if ENABLE_PLAT_COMPAT static void plat_affinst_suspend(unsigned long sec_entrypoint, unsigned int afflvl, unsigned int state) { unsigned long mpidr = read_mpidr_el1(); unsigned long cluster_id; unsigned long cpu_id; uintptr_t rv; /* Determine if any platform actions need to be executed. */ if (plat_do_plat_actions(afflvl, state) == -EAGAIN) return; cpu_id = mpidr & MPIDR_CPU_MASK; cluster_id = mpidr & MPIDR_CLUSTER_MASK; if (cluster_id) rv = (uintptr_t)&mt8173_mcucfg->mp1_rv_addr[cpu_id].rv_addr_lw; else rv = (uintptr_t)&mt8173_mcucfg->mp0_rv_addr[cpu_id].rv_addr_lw; mmio_write_32(rv, sec_entrypoint); if (afflvl < MPIDR_AFFLVL2) spm_mcdi_prepare_for_off_state(mpidr, afflvl); if (afflvl >= MPIDR_AFFLVL0) mt_platform_save_context(mpidr); /* Perform the common cluster specific operations */ if (afflvl >= MPIDR_AFFLVL1) { /* Disable coherency if this cluster is to be turned off */ plat_cci_disable(); } if (afflvl >= MPIDR_AFFLVL2) { disable_scu(mpidr); generic_timer_backup(); spm_system_suspend(); /* Prevent interrupts from spuriously waking up this cpu */ arm_gic_cpuif_deactivate(); } } #else static void plat_power_domain_suspend(const psci_power_state_t *state) { unsigned long mpidr = read_mpidr_el1(); unsigned long cluster_id; unsigned long cpu_id; uintptr_t rv; cpu_id = mpidr & MPIDR_CPU_MASK; cluster_id = mpidr & MPIDR_CLUSTER_MASK; if (cluster_id) rv = (uintptr_t)&mt8173_mcucfg->mp1_rv_addr[cpu_id].rv_addr_lw; else rv = (uintptr_t)&mt8173_mcucfg->mp0_rv_addr[cpu_id].rv_addr_lw; mmio_write_32(rv, secure_entrypoint); if (MTK_SYSTEM_PWR_STATE(state) != MTK_LOCAL_STATE_OFF) { spm_mcdi_prepare_for_off_state(mpidr, MTK_PWR_LVL0); if (MTK_CLUSTER_PWR_STATE(state) == MTK_LOCAL_STATE_OFF) spm_mcdi_prepare_for_off_state(mpidr, MTK_PWR_LVL1); } mt_platform_save_context(mpidr); /* Perform the common cluster specific operations */ if (MTK_CLUSTER_PWR_STATE(state) == MTK_LOCAL_STATE_OFF) { /* Disable coherency if this cluster is to be turned off */ plat_cci_disable(); } if (MTK_SYSTEM_PWR_STATE(state) == MTK_LOCAL_STATE_OFF) { disable_scu(mpidr); generic_timer_backup(); spm_system_suspend(); /* Prevent interrupts from spuriously waking up this cpu */ arm_gic_cpuif_deactivate(); } } #endif /******************************************************************************* * MTK_platform handler called when an affinity instance has just been powered * on after being turned off earlier. The level and mpidr determine the affinity * instance. The 'state' arg. allows the platform to decide whether the cluster * was turned off prior to wakeup and do what's necessary to setup it up * correctly. ******************************************************************************/ #if ENABLE_PLAT_COMPAT static void plat_affinst_on_finish(unsigned int afflvl, unsigned int state) { unsigned long mpidr = read_mpidr_el1(); /* Determine if any platform actions need to be executed. */ if (plat_do_plat_actions(afflvl, state) == -EAGAIN) return; /* Perform the common cluster specific operations */ if (afflvl >= MPIDR_AFFLVL1) { /* Enable coherency if this cluster was off */ plat_cci_enable(); trace_power_flow(mpidr, CLUSTER_UP); } /* Enable the gic cpu interface */ arm_gic_cpuif_setup(); arm_gic_pcpu_distif_setup(); trace_power_flow(mpidr, CPU_UP); } #else void mtk_system_pwr_domain_resume(void); static void plat_power_domain_on_finish(const psci_power_state_t *state) { unsigned long mpidr = read_mpidr_el1(); assert(state->pwr_domain_state[MPIDR_AFFLVL0] == MTK_LOCAL_STATE_OFF); if ((PLAT_MAX_PWR_LVL > MTK_PWR_LVL1) && (state->pwr_domain_state[MTK_PWR_LVL2] == MTK_LOCAL_STATE_OFF)) mtk_system_pwr_domain_resume(); if (state->pwr_domain_state[MPIDR_AFFLVL1] == MTK_LOCAL_STATE_OFF) { plat_cci_enable(); trace_power_flow(mpidr, CLUSTER_UP); } if ((PLAT_MAX_PWR_LVL > MTK_PWR_LVL1) && (state->pwr_domain_state[MTK_PWR_LVL2] == MTK_LOCAL_STATE_OFF)) return; /* Enable the gic cpu interface */ arm_gic_cpuif_setup(); arm_gic_pcpu_distif_setup(); trace_power_flow(mpidr, CPU_UP); } #endif /******************************************************************************* * MTK_platform handler called when an affinity instance has just been powered * on after having been suspended earlier. The level and mpidr determine the * affinity instance. ******************************************************************************/ #if ENABLE_PLAT_COMPAT static void plat_affinst_suspend_finish(unsigned int afflvl, unsigned int state) { unsigned long mpidr = read_mpidr_el1(); /* Determine if any platform actions need to be executed. */ if (plat_do_plat_actions(afflvl, state) == -EAGAIN) return; if (afflvl >= MPIDR_AFFLVL2) { /* Enable the gic cpu interface */ arm_gic_setup(); arm_gic_cpuif_setup(); spm_system_suspend_finish(); enable_scu(mpidr); } /* Perform the common cluster specific operations */ if (afflvl >= MPIDR_AFFLVL1) { /* Enable coherency if this cluster was off */ plat_cci_enable(); } if (afflvl >= MPIDR_AFFLVL0) mt_platform_restore_context(mpidr); if (afflvl < MPIDR_AFFLVL2) spm_mcdi_finish_for_on_state(mpidr, afflvl); arm_gic_pcpu_distif_setup(); } #else static void plat_power_domain_suspend_finish(const psci_power_state_t *state) { unsigned long mpidr = read_mpidr_el1(); if (state->pwr_domain_state[MTK_PWR_LVL0] == MTK_LOCAL_STATE_RET) return; if (MTK_SYSTEM_PWR_STATE(state) == MTK_LOCAL_STATE_OFF) { /* Enable the gic cpu interface */ arm_gic_setup(); arm_gic_cpuif_setup(); spm_system_suspend_finish(); enable_scu(mpidr); } /* Perform the common cluster specific operations */ if (MTK_CLUSTER_PWR_STATE(state) == MTK_LOCAL_STATE_OFF) { /* Enable coherency if this cluster was off */ plat_cci_enable(); } mt_platform_restore_context(mpidr); if (MTK_SYSTEM_PWR_STATE(state) != MTK_LOCAL_STATE_OFF) { spm_mcdi_finish_for_on_state(mpidr, MTK_PWR_LVL0); if (MTK_CLUSTER_PWR_STATE(state) == MTK_LOCAL_STATE_OFF) spm_mcdi_finish_for_on_state(mpidr, MTK_PWR_LVL1); } arm_gic_pcpu_distif_setup(); } #endif #if ENABLE_PLAT_COMPAT static unsigned int plat_get_sys_suspend_power_state(void) { /* StateID: 0, StateType: 1(power down), PowerLevel: 2(system) */ return psci_make_powerstate(0, 1, 2); } #else static void plat_get_sys_suspend_power_state(psci_power_state_t *req_state) { assert(PLAT_MAX_PWR_LVL >= 2); for (int i = MPIDR_AFFLVL0; i <= PLAT_MAX_PWR_LVL; i++) req_state->pwr_domain_state[i] = MTK_LOCAL_STATE_OFF; } #endif /******************************************************************************* * MTK handlers to shutdown/reboot the system ******************************************************************************/ static void __dead2 plat_system_off(void) { INFO("MTK System Off\n"); rtc_bbpu_power_down(); wfi(); ERROR("MTK System Off: operation not handled.\n"); panic(); } static void __dead2 plat_system_reset(void) { /* Write the System Configuration Control Register */ INFO("MTK System Reset\n"); mmio_clrsetbits_32(MTK_WDT_BASE, (MTK_WDT_MODE_DUAL_MODE | MTK_WDT_MODE_IRQ), MTK_WDT_MODE_KEY); mmio_setbits_32(MTK_WDT_BASE, (MTK_WDT_MODE_KEY | MTK_WDT_MODE_EXTEN)); mmio_setbits_32(MTK_WDT_SWRST, MTK_WDT_SWRST_KEY); wfi(); ERROR("MTK System Reset: operation not handled.\n"); panic(); } #if !ENABLE_PLAT_COMPAT static int plat_validate_power_state(unsigned int power_state, psci_power_state_t *req_state) { int pstate = psci_get_pstate_type(power_state); int pwr_lvl = psci_get_pstate_pwrlvl(power_state); int i; assert(req_state); if (pwr_lvl > PLAT_MAX_PWR_LVL) return PSCI_E_INVALID_PARAMS; /* Sanity check the requested state */ if (pstate == PSTATE_TYPE_STANDBY) { /* * It's possible to enter standby only on power level 0 * Ignore any other power level. */ if (pwr_lvl != 0) return PSCI_E_INVALID_PARAMS; req_state->pwr_domain_state[MTK_PWR_LVL0] = MTK_LOCAL_STATE_RET; } else { for (i = 0; i <= pwr_lvl; i++) req_state->pwr_domain_state[i] = MTK_LOCAL_STATE_OFF; } /* * We expect the 'state id' to be zero. */ if (psci_get_pstate_id(power_state)) return PSCI_E_INVALID_PARAMS; return PSCI_E_SUCCESS; } void mtk_system_pwr_domain_resume(void) { console_init(MT8173_UART0_BASE, MT8173_UART_CLOCK, MT8173_BAUDRATE); /* Assert system power domain is available on the platform */ assert(PLAT_MAX_PWR_LVL >= MTK_PWR_LVL2); arm_gic_cpuif_setup(); arm_gic_pcpu_distif_setup(); } #endif #if ENABLE_PLAT_COMPAT /******************************************************************************* * Export the platform handlers to enable psci to invoke them ******************************************************************************/ static const plat_pm_ops_t plat_plat_pm_ops = { .affinst_standby = plat_affinst_standby, .affinst_on = plat_affinst_on, .affinst_off = plat_affinst_off, .affinst_suspend = plat_affinst_suspend, .affinst_on_finish = plat_affinst_on_finish, .affinst_suspend_finish = plat_affinst_suspend_finish, .system_off = plat_system_off, .system_reset = plat_system_reset, .get_sys_suspend_power_state = plat_get_sys_suspend_power_state, }; /******************************************************************************* * Export the platform specific power ops & initialize the mtk_platform power * controller ******************************************************************************/ int platform_setup_pm(const plat_pm_ops_t **plat_ops) { *plat_ops = &plat_plat_pm_ops; return 0; } #else static const plat_psci_ops_t plat_plat_pm_ops = { .cpu_standby = plat_cpu_standby, .pwr_domain_on = plat_power_domain_on, .pwr_domain_on_finish = plat_power_domain_on_finish, .pwr_domain_off = plat_power_domain_off, .pwr_domain_suspend = plat_power_domain_suspend, .pwr_domain_suspend_finish = plat_power_domain_suspend_finish, .system_off = plat_system_off, .system_reset = plat_system_reset, .validate_power_state = plat_validate_power_state, .get_sys_suspend_power_state = plat_get_sys_suspend_power_state, }; int plat_setup_psci_ops(uintptr_t sec_entrypoint, const plat_psci_ops_t **psci_ops) { *psci_ops = &plat_plat_pm_ops; secure_entrypoint = sec_entrypoint; return 0; } /* * The PSCI generic code uses this API to let the platform participate in state * coordination during a power management operation. It compares the platform * specific local power states requested by each cpu for a given power domain * and returns the coordinated target power state that the domain should * enter. A platform assigns a number to a local power state. This default * implementation assumes that the platform assigns these numbers in order of * increasing depth of the power state i.e. for two power states X & Y, if X < Y * then X represents a shallower power state than Y. As a result, the * coordinated target local power state for a power domain will be the minimum * of the requested local power states. */ plat_local_state_t plat_get_target_pwr_state(unsigned int lvl, const plat_local_state_t *states, unsigned int ncpu) { plat_local_state_t target = PLAT_MAX_OFF_STATE, temp; assert(ncpu); do { temp = *states++; if (temp < target) target = temp; } while (--ncpu); return target; } #endif