PSCI: Add pwr_domain_pwr_down_wfi() hook in plat_psci_ops
This patch adds a new optional platform hook `pwr_domain_pwr_down_wfi()` in
the plat_psci_ops structure. This hook allows the platform to perform platform
specific actions including the wfi invocation to enter powerdown. This hook
is invoked by both psci_do_cpu_off() and psci_cpu_suspend_start() functions.
The porting-guide.md is also updated for the same.
This patch also modifies the `psci_power_down_wfi()` function to invoke
`plat_panic_handler` incase of panic instead of the busy while loop.
Fixes ARM-Software/tf-issues#375
Change-Id: Iba104469a1445ee8d59fb3a6fdd0a98e7f24dfa3
diff --git a/services/std_svc/psci/psci_entry.S b/services/std_svc/psci/psci_entry.S
index 5f4f91c..f8c0afa 100644
--- a/services/std_svc/psci/psci_entry.S
+++ b/services/std_svc/psci/psci_entry.S
@@ -106,7 +106,6 @@
func psci_power_down_wfi
dsb sy // ensure write buffer empty
wfi
-wfi_spill:
- b wfi_spill
+ bl plat_panic_handler
endfunc psci_power_down_wfi
diff --git a/services/std_svc/psci/psci_off.c b/services/std_svc/psci/psci_off.c
index cef6668..686666d 100644
--- a/services/std_svc/psci/psci_off.c
+++ b/services/std_svc/psci/psci_off.c
@@ -138,11 +138,16 @@
dsbish();
inv_cpu_data(psci_svc_cpu_data.aff_info_state);
- /*
- * Enter a wfi loop which will allow the power controller to
- * physically power down this cpu.
- */
- psci_power_down_wfi();
+ if (psci_plat_pm_ops->pwr_domain_pwr_down_wfi) {
+ /* This function must not return */
+ psci_plat_pm_ops->pwr_domain_pwr_down_wfi(&state_info);
+ } else {
+ /*
+ * Enter a wfi loop which will allow the power
+ * controller to physically power down this cpu.
+ */
+ psci_power_down_wfi();
+ }
}
return rc;
diff --git a/services/std_svc/psci/psci_suspend.c b/services/std_svc/psci/psci_suspend.c
index 367bb32..8c6ab6b 100644
--- a/services/std_svc/psci/psci_suspend.c
+++ b/services/std_svc/psci/psci_suspend.c
@@ -189,8 +189,13 @@
if (skip_wfi)
return;
- if (is_power_down_state)
- psci_power_down_wfi();
+ if (is_power_down_state) {
+ /* The function calls below must not return */
+ if (psci_plat_pm_ops->pwr_domain_pwr_down_wfi)
+ psci_plat_pm_ops->pwr_domain_pwr_down_wfi(state_info);
+ else
+ psci_power_down_wfi();
+ }
/*
* We will reach here if only retention/standby states have been