feat(psci): introduce 'pwr_domain_off_early' hook
This patch introduces the 'pwr_domain_off_early' hook for
platforms wanting to perform housekeeping steps before the
PSCI framework starts the CPU power off sequence. Platforms
might also want to use ths opportunity to ensure that the
CPU off sequence can proceed.
The PSCI framework expects a return code of PSCI_E_DENIED,
if the platform wants to halt the CPU off sequence.
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
Change-Id: I6980e84fc4d6cb80537a178d0d3d26fb28a13853
diff --git a/lib/psci/psci_off.c b/lib/psci/psci_off.c
index 637adb9..9f36ac7 100644
--- a/lib/psci/psci_off.c
+++ b/lib/psci/psci_off.c
@@ -1,5 +1,6 @@
/*
* Copyright (c) 2013-2019, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2023, NVIDIA Corporation. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@@ -57,6 +58,19 @@
psci_set_power_off_state(&state_info);
/*
+ * Call the platform provided early CPU_OFF handler to allow
+ * platforms to perform any housekeeping activities before
+ * actually powering the CPU off. PSCI_E_DENIED indicates that
+ * the CPU off sequence should be aborted at this time.
+ */
+ if (psci_plat_pm_ops->pwr_domain_off_early) {
+ rc = psci_plat_pm_ops->pwr_domain_off_early(&state_info);
+ if (rc == PSCI_E_DENIED) {
+ return rc;
+ }
+ }
+
+ /*
* Get the parent nodes here, this is important to do before we
* initiate the power down sequence as after that point the core may
* have exited coherency and its cache may be disabled, any access to