/*******************************************************************************
* 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.
******************************************************************************/
int psci_afflvl_suspend(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_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.
*/
rc = psci_get_aff_map_nodes(read_mpidr_el1() & MPIDR_AFFINITY_MASK,
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(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_SUSPEND);
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 be turned off */
psci_set_max_phys_off_afflvl(max_phys_off_afflvl);
/* Perform generic, architecture and platform specific handling */
rc = psci_call_suspend_handlers(mpidr_nodes,
start_afflvl,
end_afflvl,
entrypoint,
context_id,
power_state);
/*
* 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;
}
/*******************************************************************************
* Generic handler which is called when a cpu is physically powered on. It
* traverses through all the affinity levels performing generic, architectural,
* platform setup and state management e.g. for a cluster that's been powered
* on, it will call the platform specific code which will enable coherency at
* the interconnect level. For a cpu it could mean turning on the MMU etc.
*
* The state of all the relevant affinity levels is changed after calling the
* affinity level specific handlers as their actions would depend upon the state
* the affinity level is exiting from.
*
* The affinity level specific handlers are called in descending order i.e. from
* the highest to the lowest affinity level implemented by the platform because
* to turn on affinity level X it is neccesary to turn on affinity level X + 1
* first.
******************************************************************************/
void psci_afflvl_power_on_finish(int start_afflvl,
int end_afflvl,
afflvl_power_on_finisher_t *pon_handlers)
{
mpidr_aff_map_nodes_t mpidr_nodes;
int rc;
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. Either case is an irrecoverable error.
*/
rc = psci_get_aff_map_nodes(read_mpidr_el1() & MPIDR_AFFINITY_MASK,
start_afflvl,
end_afflvl,
mpidr_nodes);
if (rc != PSCI_E_SUCCESS)
panic();
/*
* 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);
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 come out of the OFF or
* SUSPEND states.
*/
psci_set_max_phys_off_afflvl(max_phys_off_afflvl);
/* Perform generic, architecture and platform specific handling */
psci_call_power_on_handlers(mpidr_nodes,
start_afflvl,
end_afflvl,
pon_handlers);
/*
* 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_ON);
/*
* 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);
/*
* This loop releases the lock corresponding to each affinity level
* in the reverse order to which they were acquired.
*/
psci_release_afflvl_locks(start_afflvl,
end_afflvl,
mpidr_nodes);
}
