fix(psci): add optional pwr_domain_validate_suspend to plat_psci_ops_t
This patch adds a new optional member `pwr_domain_validate_suspend` to
the `plat_psci_ops_t` structure that allows a platform to optionally
perform platform specific validations in OS-initiated mode. This is
conditionally compiled into the build depending on the value of the
`PSCI_OS_INIT_MODE` build option.
In https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/17682,
the return type of the `pwr_domain_suspend` handler was updated from
`void` to `int` to allow a platform to optionally perform platform
specific validations in OS-initiated mode. However, when an error code
other than `PSCI_E_SUCCESS` is returned, the current exit path does not
undo the operations in `psci_suspend_to_pwrdown_start`, and as a result,
the system ends up in an unexpected state.
The fix in this patch prevents the need to undo the operations in
`psci_suspend_to_pwrdown_start`, by allowing the platform to first
perform any necessary platform specific validations before the PSCI
generic code proceeds to the point of no return where the CPU_SUSPEND
request is expected to complete successfully.
Change-Id: I05d92c7ea3f5364da09af630d44d78252185db20
Signed-off-by: Wing Li <wingers@google.com>
diff --git a/lib/psci/psci_suspend.c b/lib/psci/psci_suspend.c
index 861b875..d93e60d 100644
--- a/lib/psci/psci_suspend.c
+++ b/lib/psci/psci_suspend.c
@@ -219,6 +219,19 @@
}
#endif
+#if PSCI_OS_INIT_MODE
+ if (psci_plat_pm_ops->pwr_domain_validate_suspend != NULL) {
+ rc = psci_plat_pm_ops->pwr_domain_validate_suspend(state_info);
+ if (rc != PSCI_E_SUCCESS) {
+ skip_wfi = true;
+ goto exit;
+ }
+ }
+#endif
+
+ /* Update the target state in the power domain nodes */
+ psci_set_target_local_pwr_states(end_pwrlvl, state_info);
+
#if ENABLE_PSCI_STAT
/* Update the last cpu for each level till end_pwrlvl */
psci_stats_update_pwr_down(end_pwrlvl, state_info);
@@ -234,15 +247,7 @@
* program the power controller etc.
*/
-#if PSCI_OS_INIT_MODE
- rc = psci_plat_pm_ops->pwr_domain_suspend(state_info);
- if (rc != PSCI_E_SUCCESS) {
- skip_wfi = true;
- goto exit;
- }
-#else
psci_plat_pm_ops->pwr_domain_suspend(state_info);
-#endif
#if ENABLE_PSCI_STAT
plat_psci_stat_accounting_start(state_info);