/******************************************************************************* * Top level handler which is called when a cpu wants to power itself down. * It's assumed that along with turning the cpu off, higher affinity levels will * be turned off as far as possible. It traverses through all the affinity * levels performing generic, architectural, platform setup and state management * e.g. for a cluster that's to be powered off, 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 * 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_off(unsigned long mpidr, 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. In either case, we cannot return back * to the caller as it would not know what to do. */ rc = psci_get_aff_map_nodes(mpidr, start_afflvl, end_afflvl, mpidr_nodes); assert (rc == PSCI_E_SUCCESS); /* * 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); /* Perform generic, architecture and platform specific handling */ rc = psci_call_off_handlers(mpidr_nodes, start_afflvl, end_afflvl, mpidr); /* * 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; }
/******************************************************************************* * Top level handler which is called when a cpu wants to power itself down. * It's assumed that along with turning the cpu off, higher affinity levels will * be turned off as far as possible. It traverses through all the affinity * levels performing generic, architectural, platform setup and state management * e.g. for a cluster that's to be powered off, 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 * 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. ******************************************************************************/ int psci_afflvl_off(int start_afflvl, int end_afflvl) { int rc = PSCI_E_SUCCESS; mpidr_aff_map_nodes_t mpidr_nodes; unsigned int max_phys_off_afflvl; /* * 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. In either case, we cannot return back * to the caller as it would not know what to do. */ rc = psci_get_aff_map_nodes(read_mpidr_el1() & MPIDR_AFFINITY_MASK, start_afflvl, end_afflvl, mpidr_nodes); assert (rc == PSCI_E_SUCCESS); /* * 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(start_afflvl, end_afflvl, mpidr_nodes); /* * This function updates the state of each affinity instance * corresponding to the mpidr in the range of affinity levels * specified. */ psci_do_afflvl_state_mgmt(start_afflvl, end_afflvl, mpidr_nodes, PSCI_STATE_OFF); max_phys_off_afflvl = psci_find_max_phys_off_afflvl(start_afflvl, end_afflvl, mpidr_nodes); assert(max_phys_off_afflvl != PSCI_INVALID_DATA); /* Stash the highest affinity level that will enter the OFF state. */ psci_set_max_phys_off_afflvl(max_phys_off_afflvl); /* Perform generic, architecture and platform specific handling */ rc = psci_call_off_handlers(mpidr_nodes, start_afflvl, end_afflvl); /* * Invalidate the entry for the highest affinity level stashed earlier. * This ensures that any reads of this variable outside the power * up/down sequences return PSCI_INVALID_DATA. * */ psci_set_max_phys_off_afflvl(PSCI_INVALID_DATA); /* * Release the locks corresponding to each affinity level in the * reverse order to which they were acquired. */ psci_release_afflvl_locks(start_afflvl, end_afflvl, mpidr_nodes); return rc; }