[PATCH 4/5] firmware: psci: Add function to fetch SMCCC version

From: Sudeep Holla
Date: Thu Apr 30 2020 - 07:48:50 EST


For backward compatibility reasons, PSCI maintains SMCCC version as
SMCCC didn't provide ARM_SMCCC_VERSION_FUNC_ID until v1.1

Let us provide accessors to fetch the SMCCC version in PSCI so that
other SMCCC v1.1+ features can use it.

Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
---
drivers/firmware/psci/psci.c | 5 +++++
include/linux/arm-smccc.h | 9 +++++++++
2 files changed, 14 insertions(+)

diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c
index 6a56d7196697..04426e16fee6 100644
--- a/drivers/firmware/psci/psci.c
+++ b/drivers/firmware/psci/psci.c
@@ -65,6 +65,11 @@ enum arm_smccc_conduit arm_smccc_1_1_get_conduit(void)
return psci_ops.conduit;
}

+u32 arm_smccc_get_version(void)
+{
+ return psci_ops.smccc_version;
+}
+
typedef unsigned long (psci_fn)(unsigned long, unsigned long,
unsigned long, unsigned long);
static psci_fn *invoke_psci_fn;
diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
index 9d9a2e42e919..d6b0f4acc707 100644
--- a/include/linux/arm-smccc.h
+++ b/include/linux/arm-smccc.h
@@ -98,6 +98,15 @@ enum arm_smccc_conduit {
*/
enum arm_smccc_conduit arm_smccc_1_1_get_conduit(void);

+/**
+ * arm_smccc_get_version()
+ *
+ * Returns the version to be used for SMCCCv1.1 or later.
+ *
+ * When SMCCCv1.1 or above is not present, assumes and returns SMCCCv1.0.
+ */
+u32 arm_smccc_get_version(void);
+
/**
* struct arm_smccc_res - Result from SMC/HVC call
* @a0-a3 result values from registers 0 to 3
--
2.17.1