To allow subsequent changes to implement support for OSI mode through the
cpuidle-psci driver, export the existing psci_has_osi_support(). Export
also a new function, psci_set_osi_mode(), that allows its caller to enable
the OS-initiated CPU-suspend mode in the PSCI FW.
To deal with backwards compatibility for a kernel started through a kexec
call, default to set the CPU-suspend mode to the Platform Coordinated mode
during boot.
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
---
drivers/firmware/psci/psci.c | 18 ++++++++++++++++--
include/linux/psci.h | 2 ++
2 files changed, 18 insertions(+), 2 deletions(-)
diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c
index 84f4ff351c62..76f3a991d4d7 100644
--- a/drivers/firmware/psci/psci.c
+++ b/drivers/firmware/psci/psci.c
@@ -89,7 +89,7 @@ static inline bool psci_has_ext_power_state(void)
PSCI_1_0_FEATURES_CPU_SUSPEND_PF_MASK;
}
-static inline bool psci_has_osi_support(void)
+bool psci_has_osi_support(void)
{
return psci_cpu_suspend_feature & PSCI_1_0_OS_INITIATED;
}
@@ -154,6 +154,15 @@ static u32 psci_get_version(void)
return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
}
+int psci_set_osi_mode(void)
+{
+ int err;
+
+ err = invoke_psci_fn(PSCI_1_0_FN_SET_SUSPEND_MODE,
+ PSCI_1_0_SUSPEND_MODE_OSI, 0, 0);
+ return psci_to_linux_errno(err);
+}
+
static int psci_cpu_suspend(u32 state, unsigned long entry_point)
{
int err;
@@ -536,9 +545,14 @@ static int __init psci_1_0_init(struct device_node *np)
if (err)
return err;
- if (psci_has_osi_support())
+ if (psci_has_osi_support()) {
pr_info("OSI mode supported.\n");
+ /* Default to PC mode. */
+ invoke_psci_fn(PSCI_1_0_FN_SET_SUSPEND_MODE,
+ PSCI_1_0_SUSPEND_MODE_PC, 0, 0);
+ }
+
return 0;
}
diff --git a/include/linux/psci.h b/include/linux/psci.h
index e2bacc6fd2f2..f76b45341adf 100644
--- a/include/linux/psci.h
+++ b/include/linux/psci.h
@@ -17,6 +17,8 @@ bool psci_tos_resident_on(int cpu);
int psci_cpu_suspend_enter(u32 state);
bool psci_power_state_is_valid(u32 state);
+int psci_set_osi_mode(void);
+bool psci_has_osi_support(void);
enum psci_conduit {
PSCI_CONDUIT_NONE,
--
2.17.1
