PSCI: Invoke PM hooks only for the highest level
This patch optimizes the invocation of the platform power management hooks for
ON, OFF and SUSPEND such that they are called only for the highest affinity
level which will be powered off/on. Earlier, the hooks were being invoked for
all the intermediate levels as well.
This patch requires that the platforms migrate to the new semantics of the PM
hooks. It also removes the `state` parameter from the pm hooks as the `afflvl`
parameter now indicates the highest affinity level for which power management
operations are required.
Change-Id: I57c87931d8a2723aeade14acc710e5b78ac41732
diff --git a/services/std_svc/psci1.0/psci_afflvl_off.c b/services/std_svc/psci1.0/psci_afflvl_off.c
index 7eb9688..b966822 100644
--- a/services/std_svc/psci1.0/psci_afflvl_off.c
+++ b/services/std_svc/psci1.0/psci_afflvl_off.c
@@ -35,122 +35,19 @@
#include <string.h>
#include "psci_private.h"
-typedef void (*afflvl_off_handler_t)(aff_map_node_t *node);
-
-/*******************************************************************************
- * The next three functions implement a handler for each supported affinity
- * level which is called when that affinity level is turned off.
- ******************************************************************************/
-static void psci_afflvl0_off(aff_map_node_t *cpu_node)
-{
- assert(cpu_node->level == MPIDR_AFFLVL0);
-
- /*
- * Arch. management. Perform the necessary steps to flush all
- * cpu caches.
- */
- psci_do_pwrdown_cache_maintenance(MPIDR_AFFLVL0);
-
- /*
- * Plat. management: Perform platform specific actions to turn this
- * cpu off e.g. exit cpu coherency, program the power controller etc.
- */
- psci_plat_pm_ops->affinst_off(cpu_node->level,
- psci_get_phys_state(cpu_node));
-}
-
-static void psci_afflvl1_off(aff_map_node_t *cluster_node)
-{
- /* Sanity check the cluster level */
- assert(cluster_node->level == MPIDR_AFFLVL1);
-
- /*
- * Arch. Management. Flush all levels of caches to PoC if
- * the cluster is to be shutdown.
- */
- psci_do_pwrdown_cache_maintenance(MPIDR_AFFLVL1);
-
- /*
- * Plat. Management. Allow the platform to do its cluster
- * specific bookeeping e.g. turn off interconnect coherency,
- * program the power controller etc.
- */
- psci_plat_pm_ops->affinst_off(cluster_node->level,
- psci_get_phys_state(cluster_node));
-}
-
-static void psci_afflvl2_off(aff_map_node_t *system_node)
-{
- /* Cannot go beyond this level */
- assert(system_node->level == MPIDR_AFFLVL2);
-
- /*
- * Keep the physical state of the system handy to decide what
- * action needs to be taken
- */
-
- /*
- * Arch. Management. Flush all levels of caches to PoC if
- * the system is to be shutdown.
- */
- psci_do_pwrdown_cache_maintenance(MPIDR_AFFLVL2);
-
- /*
- * Plat. Management : Allow the platform to do its bookeeping
- * at this affinity level
- */
- psci_plat_pm_ops->affinst_off(system_node->level,
- psci_get_phys_state(system_node));
-}
-
-static const afflvl_off_handler_t psci_afflvl_off_handlers[] = {
- psci_afflvl0_off,
- psci_afflvl1_off,
- psci_afflvl2_off,
-};
-
-/*******************************************************************************
- * This function takes an array of pointers to affinity instance nodes in the
- * topology tree and calls the off handler for the corresponding affinity
- * levels
- ******************************************************************************/
-static void psci_call_off_handlers(aff_map_node_t *mpidr_nodes[],
- int start_afflvl,
- int end_afflvl)
-{
- int level;
- aff_map_node_t *node;
-
- for (level = start_afflvl; level <= end_afflvl; level++) {
- node = mpidr_nodes[level];
- if (node == NULL)
- continue;
-
- psci_afflvl_off_handlers[level](node);
- }
-}
-
-/*******************************************************************************
+/******************************************************************************
* 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.
+ * It's assumed that along with turning the cpu off, higher affinity levels
+ * will be turned off as far as possible. It finds the highest level to be
+ * powered off by traversing the node information and then performs generic,
+ * architectural, platform setup and state management required to turn OFF
+ * that affinity level and affinity levels below it. e.g. For a cpu that's to
+ * be powered OFF, it could mean programming the power controller whereas 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 and also the program the power controller.
******************************************************************************/
-int psci_afflvl_off(int start_afflvl,
- int end_afflvl)
+int psci_afflvl_off(int end_afflvl)
{
int rc;
mpidr_aff_map_nodes_t mpidr_nodes;
@@ -170,7 +67,7 @@
* therefore assert.
*/
rc = psci_get_aff_map_nodes(read_mpidr_el1() & MPIDR_AFFINITY_MASK,
- start_afflvl,
+ MPIDR_AFFLVL0,
end_afflvl,
mpidr_nodes);
assert(rc == PSCI_E_SUCCESS);
@@ -180,7 +77,7 @@
* 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,
+ psci_acquire_afflvl_locks(MPIDR_AFFLVL0,
end_afflvl,
mpidr_nodes);
@@ -201,38 +98,34 @@
* corresponding to the mpidr in the range of affinity levels
* specified.
*/
- psci_do_afflvl_state_mgmt(start_afflvl,
+ psci_do_afflvl_state_mgmt(MPIDR_AFFLVL0,
end_afflvl,
mpidr_nodes,
PSCI_STATE_OFF);
- max_phys_off_afflvl = psci_find_max_phys_off_afflvl(start_afflvl,
+ max_phys_off_afflvl = psci_find_max_phys_off_afflvl(MPIDR_AFFLVL0,
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 */
- psci_call_off_handlers(mpidr_nodes,
- start_afflvl,
- end_afflvl);
+ /*
+ * Arch. management. Perform the necessary steps to flush all
+ * cpu caches.
+ */
+ psci_do_pwrdown_cache_maintenance(max_phys_off_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.
- *
+ * Plat. management: Perform platform specific actions to turn this
+ * cpu off e.g. exit cpu coherency, program the power controller etc.
*/
- psci_set_max_phys_off_afflvl(PSCI_INVALID_DATA);
+ psci_plat_pm_ops->affinst_off(max_phys_off_afflvl);
exit:
/*
* Release the locks corresponding to each affinity level in the
* reverse order to which they were acquired.
*/
- psci_release_afflvl_locks(start_afflvl,
+ psci_release_afflvl_locks(MPIDR_AFFLVL0,
end_afflvl,
mpidr_nodes);