Commit 49fdcd75 authored by Ulf Hansson's avatar Ulf Hansson
Browse files

firmware: psci: Export functions to manage the OSI mode 



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: default avatarUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: default avatarSudeep Holla <sudeep.holla@arm.com>
parent a3f048b5

drivers/firmware/psci/psci.c

+16 −2
Original line number Diff line number Diff line
@@ -97,7 +97,7 @@ 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;

}
@@ -162,6 +162,15 @@ 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;
@@ -544,9 +553,14 @@ 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;

}

include/linux/psci.h

+2 −0
Original line number Diff line number Diff line
@@ -18,6 +18,8 @@ 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 smccc_version {

	SMCCC_VERSION_1_0,

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