[RFC 4/7] psci: Add cpu_poke ops to support core poking

Abel Vesa
2019-03-27T13:21:42Z

There can be platforms that need a dedicated work to be done
in TF-A before the specified core can be woken up through an IPI.
Allow those platforms to call into the TF-A to do that work
by making use of the cpu_poke operation.

Signed-off-by: Abel Vesa <abel.vesa@nxp.com>
---
arch/arm64/include/asm/cpu_ops.h | 1 +
arch/arm64/kernel/psci.c | 1 +
drivers/firmware/psci.c | 6 ++++++
include/linux/psci.h | 1 +
include/uapi/linux/psci.h | 2 ++
5 files changed, 11 insertions(+)

diff --git a/arch/arm64/include/asm/cpu_ops.h b/arch/arm64/include/asm/cpu_ops.h
index 8f03446..913afef 100644
--- a/arch/arm64/include/asm/cpu_ops.h
+++ b/arch/arm64/include/asm/cpu_ops.h
@@ -60,6 +60,7 @@ struct cpu_operations {
#ifdef CONFIG_CPU_IDLE
int (*cpu_init_idle)(unsigned int);
int (*cpu_suspend)(unsigned long);
+ int (*cpu_poke)(unsigned int);
#endif
};

diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c
index 8cdaf25..53227eb 100644
--- a/arch/arm64/kernel/psci.c
+++ b/arch/arm64/kernel/psci.c
@@ -115,6 +115,7 @@ const struct cpu_operations cpu_psci_ops = {
#ifdef CONFIG_CPU_IDLE
.cpu_init_idle = psci_cpu_init_idle,
.cpu_suspend = psci_cpu_suspend_enter,
+ .cpu_poke = psci_cpu_suspend_exit,
#endif
.cpu_init = cpu_psci_cpu_init,
.cpu_prepare = cpu_psci_cpu_prepare,
diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c
index c80ec1d..282bc47 100644
--- a/drivers/firmware/psci.c
+++ b/drivers/firmware/psci.c
@@ -73,6 +73,7 @@ enum psci_function {
PSCI_FN_CPU_ON,
PSCI_FN_CPU_OFF,
PSCI_FN_MIGRATE,
+ PSCI_FN_CPU_POKE,
PSCI_FN_MAX,
};

@@ -424,6 +425,11 @@ int psci_cpu_suspend_enter(unsigned long index)
return ret;
}

+int psci_cpu_suspend_exit(unsigned int index)
+{
+ return invoke_psci_fn(PSCI_0_2_FN_CPU_POKE, index, 0, 0);
+}
+
/* ARM specific CPU idle operations */
#ifdef CONFIG_ARM
static const struct cpuidle_ops psci_cpuidle_ops __initconst = {
diff --git a/include/linux/psci.h b/include/linux/psci.h
index 8b1b3b5..d863733 100644
--- a/include/linux/psci.h
+++ b/include/linux/psci.h
@@ -24,6 +24,7 @@ bool psci_tos_resident_on(int cpu);

int psci_cpu_init_idle(unsigned int cpu);
int psci_cpu_suspend_enter(unsigned long index);
+int psci_cpu_suspend_exit(unsigned int index);

enum psci_conduit {
PSCI_CONDUIT_NONE,
diff --git a/include/uapi/linux/psci.h b/include/uapi/linux/psci.h
index b3bcabe..19e7481 100644
--- a/include/uapi/linux/psci.h
+++ b/include/uapi/linux/psci.h
@@ -40,8 +40,10 @@
#define PSCI_0_2_FN_MIGRATE_INFO_UP_CPU PSCI_0_2_FN(7)
#define PSCI_0_2_FN_SYSTEM_OFF PSCI_0_2_FN(8)
#define PSCI_0_2_FN_SYSTEM_RESET PSCI_0_2_FN(9)
+#define PSCI_0_2_FN_CPU_POKE PSCI_0_2_FN(11)

#define PSCI_0_2_FN64_CPU_SUSPEND PSCI_0_2_FN64(1)
+#define PSCI_0_2_FN64_CPU_POKE PSCI_0_2_FN64(11)
#define PSCI_0_2_FN64_CPU_ON PSCI_0_2_FN64(3)
#define PSCI_0_2_FN64_AFFINITY_INFO PSCI_0_2_FN64(4)
#define PSCI_0_2_FN64_MIGRATE PSCI_0_2_FN64(5)
--
2.7.4