/* * Copyright (c) 2013-2014, 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 typedef int (*afflvl_suspend_handler)(unsigned long, aff_map_node *, unsigned long, unsigned long, unsigned int); /******************************************************************************* * This function sets the affinity level till which the current cpu is being * powered down to during a cpu_suspend call ******************************************************************************/ void psci_set_suspend_afflvl(aff_map_node *node, int afflvl) { /* * Check that nobody else is calling this function on our behalf & * this information is being set only in the cpu node */ assert(node->mpidr == (read_mpidr() & MPIDR_AFFINITY_MASK)); assert(node->level == MPIDR_AFFLVL0); /* * Store the affinity level we are powering down to in our context. * The cache flush in the suspend code will ensure that this info * is available immediately upon resuming. */ psci_suspend_context[node->data].suspend_level = afflvl; } /******************************************************************************* * This function gets the affinity level till which the current cpu was powered * down during a cpu_suspend call. ******************************************************************************/ int psci_get_suspend_afflvl(aff_map_node *node) { /* Return the target affinity level */ return psci_suspend_context[node->data].suspend_level; } /******************************************************************************* * The next three functions implement a handler for each supported affinity * level which is called when that affinity level is about to be suspended. ******************************************************************************/ static int psci_afflvl0_suspend(unsigned long mpidr, aff_map_node *cpu_node, unsigned long ns_entrypoint, unsigned long context_id, unsigned int power_state) { unsigned int index, plat_state; unsigned long psci_entrypoint, sctlr = read_sctlr(); el3_state *saved_el3_state; int rc = PSCI_E_SUCCESS; /* Sanity check to safeguard against data corruption */ assert(cpu_node->level == MPIDR_AFFLVL0); /* State management: mark this cpu as suspended */ psci_set_state(cpu_node, PSCI_STATE_SUSPEND); /* * Generic management: Store the re-entry information for the * non-secure world */ index = cpu_node->data; rc = psci_set_ns_entry_info(index, ns_entrypoint, context_id); if (rc != PSCI_E_SUCCESS) return rc; /* * Arch. management: Save the EL3 state in the 'cpu_context' * structure that has been allocated for this cpu, flush the * L1 caches and exit intra-cluster coherency et al */ cm_el3_sysregs_context_save(NON_SECURE); rc = PSCI_E_SUCCESS; /* * The EL3 state to PoC since it will be accessed after a * reset with the caches turned off */ saved_el3_state = get_el3state_ctx(cm_get_context(mpidr, NON_SECURE)); flush_dcache_range((uint64_t) saved_el3_state, sizeof(*saved_el3_state)); /* Set the secure world (EL3) re-entry point after BL1 */ psci_entrypoint = (unsigned long) psci_aff_suspend_finish_entry; /* * Arch. management. Perform the necessary steps to flush all * cpu caches. * * TODO: This power down sequence varies across cpus so it needs to be * abstracted out on the basis of the MIDR like in cpu_reset_handler(). * Do the bare minimal for the time being. Fix this before porting to * Cortex models. */ sctlr &= ~SCTLR_C_BIT; write_sctlr(sctlr); /* * CAUTION: This flush to the level of unification makes an assumption * about the cache hierarchy at affinity level 0 (cpu) in the platform. * Ideally the platform should tell psci which levels to flush to exit * coherency. */ dcsw_op_louis(DCCISW); /* * Plat. management: Allow the platform to perform the * necessary actions to turn off this cpu e.g. set the * platform defined mailbox with the psci entrypoint, * program the power controller etc. */ if (psci_plat_pm_ops->affinst_suspend) { plat_state = psci_get_phys_state(cpu_node); rc = psci_plat_pm_ops->affinst_suspend(mpidr, psci_entrypoint, ns_entrypoint, cpu_node->level, plat_state); } return rc; } static int psci_afflvl1_suspend(unsigned long mpidr, aff_map_node *cluster_node, unsigned long ns_entrypoint, unsigned long context_id, unsigned int power_state) { int rc = PSCI_E_SUCCESS; unsigned int plat_state; unsigned long psci_entrypoint; /* Sanity check the cluster level */ assert(cluster_node->level == MPIDR_AFFLVL1); /* State management: Decrement the cluster reference count */ psci_set_state(cluster_node, PSCI_STATE_SUSPEND); /* * Keep the physical state of this cluster handy to decide * what action needs to be taken */ plat_state = psci_get_phys_state(cluster_node); /* * Arch. management: Flush all levels of caches to PoC if the * cluster is to be shutdown */ if (plat_state == PSCI_STATE_OFF) dcsw_op_all(DCCISW); /* * Plat. Management. Allow the platform to do its cluster * specific bookeeping e.g. turn off interconnect coherency, * program the power controller etc. */ if (psci_plat_pm_ops->affinst_suspend) { /* * Sending the psci entrypoint is currently redundant * beyond affinity level 0 but one never knows what a * platform might do. Also it allows us to keep the * platform handler prototype the same. */ psci_entrypoint = (unsigned long) psci_aff_suspend_finish_entry; rc = psci_plat_pm_ops->affinst_suspend(mpidr, psci_entrypoint, ns_entrypoint, cluster_node->level, plat_state); } return rc; } static int psci_afflvl2_suspend(unsigned long mpidr, aff_map_node *system_node, unsigned long ns_entrypoint, unsigned long context_id, unsigned int power_state) { int rc = PSCI_E_SUCCESS; unsigned int plat_state; unsigned long psci_entrypoint; /* Cannot go beyond this */ assert(system_node->level == MPIDR_AFFLVL2); /* State management: Decrement the system reference count */ psci_set_state(system_node, PSCI_STATE_SUSPEND); /* * Keep the physical state of the system handy to decide what * action needs to be taken */ plat_state = psci_get_phys_state(system_node); /* * Plat. Management : Allow the platform to do its bookeeping * at this affinity level */ if (psci_plat_pm_ops->affinst_suspend) { /* * Sending the psci entrypoint is currently redundant * beyond affinity level 0 but one never knows what a * platform might do. Also it allows us to keep the * platform handler prototype the same. */ psci_entrypoint = (unsigned long) psci_aff_suspend_finish_entry; rc = psci_plat_pm_ops->affinst_suspend(mpidr, psci_entrypoint, ns_entrypoint, system_node->level, plat_state); } return rc; } static const afflvl_suspend_handler psci_afflvl_suspend_handlers[] = { psci_afflvl0_suspend, psci_afflvl1_suspend, psci_afflvl2_suspend, }; /******************************************************************************* * This function takes an array of pointers to affinity instance nodes in the * topology tree and calls the suspend handler for the corresponding affinity * levels ******************************************************************************/ static int psci_call_suspend_handlers(mpidr_aff_map_nodes mpidr_nodes, int start_afflvl, int end_afflvl, unsigned long mpidr, unsigned long entrypoint, unsigned long context_id, unsigned int power_state) { int rc = PSCI_E_INVALID_PARAMS, level; aff_map_node *node; for (level = start_afflvl; level <= end_afflvl; level++) { node = mpidr_nodes[level]; if (node == NULL) continue; /* * TODO: In case of an error should there be a way * of restoring what we might have torn down at * lower affinity levels. */ rc = psci_afflvl_suspend_handlers[level](mpidr, node, entrypoint, context_id, power_state); if (rc != PSCI_E_SUCCESS) break; } return rc; } /******************************************************************************* * Top level handler which is called when a cpu wants to suspend its execution. * It is assumed that along with turning the cpu off, higher affinity levels * until the target affinity level will be turned off as well. It traverses * through all the affinity levels performing generic, architectural, platform * setup and state management e.g. for a cluster that's to be suspended, it will * call the platform specific code which will disable coherency at the * interconnect level if the cpu is the last in the cluster. For a cpu it could * mean programming the power controller etc. * * The state of all the relevant affinity levels is changed prior to calling the * affinity level specific handlers as their actions would depend upon the state * the affinity level is about to enter. * * The affinity level specific handlers are called in ascending order i.e. from * the lowest to the highest affinity level implemented by the platform because * to turn off affinity level X it is neccesary to turn off affinity level X - 1 * first. * * CAUTION: This function is called with coherent stacks so that coherency can * be turned off and caches can be flushed safely. ******************************************************************************/ int psci_afflvl_suspend(unsigned long mpidr, unsigned long entrypoint, unsigned long context_id, unsigned int power_state, int start_afflvl, int end_afflvl) { int rc = PSCI_E_SUCCESS; mpidr_aff_map_nodes mpidr_nodes; mpidr &= MPIDR_AFFINITY_MASK; /* * Collect the pointers to the nodes in the topology tree for * each affinity instance in the mpidr. If this function does * not return successfully then either the mpidr or the affinity * levels are incorrect. */ rc = psci_get_aff_map_nodes(mpidr, start_afflvl, end_afflvl, mpidr_nodes); if (rc != PSCI_E_SUCCESS) return rc; /* * This function acquires the lock corresponding to each affinity * level so that by the time all locks are taken, the system topology * is snapshot and state management can be done safely. */ psci_acquire_afflvl_locks(mpidr, start_afflvl, end_afflvl, mpidr_nodes); /* Save the affinity level till which this cpu can be powered down */ psci_set_suspend_afflvl(mpidr_nodes[MPIDR_AFFLVL0], end_afflvl); /* Perform generic, architecture and platform specific handling */ rc = psci_call_suspend_handlers(mpidr_nodes, start_afflvl, end_afflvl, mpidr, entrypoint, context_id, power_state); /* * Release the locks corresponding to each affinity level in the * reverse order to which they were acquired. */ psci_release_afflvl_locks(mpidr, start_afflvl, end_afflvl, mpidr_nodes); return rc; } /******************************************************************************* * The following functions finish an earlier affinity suspend request. They * are called by the common finisher routine in psci_common.c. ******************************************************************************/ static unsigned int psci_afflvl0_suspend_finish(unsigned long mpidr, aff_map_node *cpu_node) { unsigned int index, plat_state, state, rc = PSCI_E_SUCCESS; assert(cpu_node->level == MPIDR_AFFLVL0); /* Ensure we have been woken up from a suspended state */ state = psci_get_state(cpu_node); assert(state == PSCI_STATE_SUSPEND); /* * Plat. management: Perform the platform specific actions * before we change the state of the cpu e.g. enabling the * gic or zeroing the mailbox register. If anything goes * wrong then assert as there is no way to recover from this * situation. */ if (psci_plat_pm_ops->affinst_suspend_finish) { /* Get the physical state of this cpu */ plat_state = get_phys_state(state); rc = psci_plat_pm_ops->affinst_suspend_finish(mpidr, cpu_node->level, plat_state); assert(rc == PSCI_E_SUCCESS); } /* Get the index for restoring the re-entry information */ index = cpu_node->data; /* * Arch. management: Restore the stashed EL3 architectural * context from the 'cpu_context' structure for this cpu. */ cm_el3_sysregs_context_restore(NON_SECURE); rc = PSCI_E_SUCCESS; /* * Generic management: Now we just need to retrieve the * information that we had stashed away during the suspend * call to set this cpu on its way. */ psci_get_ns_entry_info(index); /* State management: mark this cpu as on */ psci_set_state(cpu_node, PSCI_STATE_ON); /* Clean caches before re-entering normal world */ dcsw_op_louis(DCCSW); return rc; } static unsigned int psci_afflvl1_suspend_finish(unsigned long mpidr, aff_map_node *cluster_node) { unsigned int plat_state, rc = PSCI_E_SUCCESS; assert(cluster_node->level == MPIDR_AFFLVL1); /* * Plat. management: Perform the platform specific actions * as per the old state of the cluster e.g. enabling * coherency at the interconnect depends upon the state with * which this cluster was powered up. If anything goes wrong * then assert as there is no way to recover from this * situation. */ if (psci_plat_pm_ops->affinst_suspend_finish) { /* Get the physical state of this cpu */ plat_state = psci_get_phys_state(cluster_node); rc = psci_plat_pm_ops->affinst_suspend_finish(mpidr, cluster_node->level, plat_state); assert(rc == PSCI_E_SUCCESS); } /* State management: Increment the cluster reference count */ psci_set_state(cluster_node, PSCI_STATE_ON); return rc; } static unsigned int psci_afflvl2_suspend_finish(unsigned long mpidr, aff_map_node *system_node) { unsigned int plat_state, rc = PSCI_E_SUCCESS;; /* Cannot go beyond this affinity level */ assert(system_node->level == MPIDR_AFFLVL2); /* * Currently, there are no architectural actions to perform * at the system level. */ /* * Plat. management: Perform the platform specific actions * as per the old state of the cluster e.g. enabling * coherency at the interconnect depends upon the state with * which this cluster was powered up. If anything goes wrong * then assert as there is no way to recover from this * situation. */ if (psci_plat_pm_ops->affinst_suspend_finish) { /* Get the physical state of the system */ plat_state = psci_get_phys_state(system_node); rc = psci_plat_pm_ops->affinst_suspend_finish(mpidr, system_node->level, plat_state); assert(rc == PSCI_E_SUCCESS); } /* State management: Increment the system reference count */ psci_set_state(system_node, PSCI_STATE_ON); return rc; } const afflvl_power_on_finisher psci_afflvl_suspend_finishers[] = { psci_afflvl0_suspend_finish, psci_afflvl1_suspend_finish, psci_afflvl2_suspend_finish, };