[PATCH 2/2] firmware: psci: support SMCCC v1.2 for SMCCC conduit

[Etienne Carriere]

Update PSCI driver to support SMCCC v1.2 reported by secure firmware
and indirectly make SMCCC conduit properly set when so. TF-A release
v2.3 implements and reports SMCCC v1.2 since commit [1].

Link: [1] https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/commit/?id=e34cc0cedca6e229847c232fe58d37fad2610ce9
Signed-off-by: Etienne Carriere <etienne.carriere@xxxxxxxxxx>
---
 drivers/firmware/psci/psci.c | 14 ++++++++++----
 include/linux/psci.h         |  1 +
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c
index 2937d44b5df4..80cf73bea4b0 100644
--- a/drivers/firmware/psci/psci.c
+++ b/drivers/firmware/psci/psci.c
@@ -409,11 +409,17 @@ static void __init psci_init_smccc(void)
 	feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID);
 
 	if (feature != PSCI_RET_NOT_SUPPORTED) {
-		u32 ret;
-		ret = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
-		if (ret == ARM_SMCCC_VERSION_1_1) {
+		ver = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0);
+
+		switch (ver) {
+		case ARM_SMCCC_VERSION_1_1:
 			psci_ops.smccc_version = SMCCC_VERSION_1_1;
-			ver = ret;
+			break;
+		case ARM_SMCCC_VERSION_1_2:
+			psci_ops.smccc_version = SMCCC_VERSION_1_2;
+			break;
+		default:
+			break;
 		}
 	}
 
diff --git a/include/linux/psci.h b/include/linux/psci.h
index a67712b73b6c..c7d99b7f34ed 100644
--- a/include/linux/psci.h
+++ b/include/linux/psci.h
@@ -24,6 +24,7 @@ bool psci_has_osi_support(void);
 enum smccc_version {
 	SMCCC_VERSION_1_0,
 	SMCCC_VERSION_1_1,
+	SMCCC_VERSION_1_2,
 };
 
 struct psci_operations {
-- 
2.17.1