Adding new optional PSCI hook pwr_domain_on_finish_late

This PSCI hook is similar to pwr_domain_on_finish but is
guaranteed to be invoked with the respective core and cluster are
participating in coherency. This will be necessary to safely invoke
the new GICv3 API which modifies shared GIC data structures concurrently.

Change-Id: I8e54f05c9d4ef5712184c9c18ba45ac97a29eb7a
Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>

diff --git a/docs/getting_started/porting-guide.rst b/docs/getting_started/porting-guide.rst
index 5786dd38495f69323dd3ff6ee4a9ee5c9a8c4ce3..af36b6a5f208bbdc8b27a36b35195ed2e1e6907f 100644 (file)
--- a/docs/getting_started/porting-guide.rst
+++ b/docs/getting_started/porting-guide.rst
@@ -2202,6 +2202,19 @@ immediately before the CPU was turned on. It indicates which power domains
 above the CPU might require initialization due to having previously been in
 low power states. The generic code expects the handler to succeed.
 
+plat_psci_ops.pwr_domain_on_finish_late() [optional]
+...........................................................
+
+This optional function is called by the PSCI implementation after the calling
+CPU is fully powered on with respective data caches enabled. The calling CPU and
+the associated cluster are guaranteed to be participating in coherency. This
+function gives the flexibility to perform any platform-specific actions safely,
+such as initialization or modification of shared data structures, without the
+overhead of explicit cache maintainace operations.
+
+The ``target_state`` has a similar meaning as described in the ``pwr_domain_on_finish()``
+operation. The generic code expects the handler to succeed.
+
 plat_psci_ops.pwr_domain_suspend_finish()
 .........................................
 

diff --git a/include/lib/psci/psci.h b/include/lib/psci/psci.h
index 04e5e3d7261aa09d9fc4e3ca2252f88df5db5e1b..7f7b7e3ff5262b08aef36c9a020eeb674dc18cd0 100644 (file)
--- a/include/lib/psci/psci.h
+++ b/include/lib/psci/psci.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2019, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -301,6 +301,8 @@ typedef struct plat_psci_ops {
                                const psci_power_state_t *target_state);
        void (*pwr_domain_suspend)(const psci_power_state_t *target_state);
        void (*pwr_domain_on_finish)(const psci_power_state_t *target_state);
+       void (*pwr_domain_on_finish_late)(
+                               const psci_power_state_t *target_state);
        void (*pwr_domain_suspend_finish)(
                                const psci_power_state_t *target_state);
        void __dead2 (*pwr_domain_pwr_down_wfi)(

diff --git a/lib/psci/psci_on.c b/lib/psci/psci_on.c
index aa6b324ed69e6dcc44113608f1a11dc61b537105..470b4f33ec4a49c9a5eeea6256b0c00d58e88596 100644 (file)
--- a/lib/psci/psci_on.c
+++ b/lib/psci/psci_on.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2013-2019, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -181,6 +181,14 @@ void psci_cpu_on_finish(int cpu_idx, const psci_power_state_t *state_info)
        psci_do_pwrup_cache_maintenance();
 #endif
 
+       /*
+        * Plat. management: Perform any platform specific actions which
+        * can only be done with the cpu and the cluster guaranteed to
+        * be coherent.
+        */
+       if (psci_plat_pm_ops->pwr_domain_on_finish_late != NULL)
+               psci_plat_pm_ops->pwr_domain_on_finish_late(state_info);
+
        /*
         * All the platform specific actions for turning this cpu
         * on have completed. Perform enough arch.initialization