[PATCH v4 1/4] firmware: keembay: Add support for Arm Trusted Firmware Service call

From: muhammad . husaini . zulkifli
Date: Wed Oct 07 2020 - 22:12:58 EST


From: Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@xxxxxxxxx>

Add header file to handle API function for device driver to communicate
with Arm Trusted Firmware.

Signed-off-by: Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@xxxxxxxxx>
---
.../linux/firmware/intel/keembay_firmware.h | 47 +++++++++++++++++++
1 file changed, 47 insertions(+)
create mode 100644 include/linux/firmware/intel/keembay_firmware.h

diff --git a/include/linux/firmware/intel/keembay_firmware.h b/include/linux/firmware/intel/keembay_firmware.h
new file mode 100644
index 000000000000..8a62abcdfead
--- /dev/null
+++ b/include/linux/firmware/intel/keembay_firmware.h
@@ -0,0 +1,47 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Intel Keembay SOC Firmware API Layer
+ *
+ * Copyright (C) 2020-2021, Intel Corporation
+ *
+ * Muhammad Husaini Zulkifli <Muhammad.Husaini.Zulkifli@xxxxxxxxx>
+ */
+
+#ifndef __FIRMWARE_KEEMBAY_SMC_H__
+#define __FIRMWARE_KEEMBAY_SMC_H__
+
+#include <linux/arm-smccc.h>
+
+/*
+ * This file defines API function that can be called by device driver in order to
+ * communicate with Arm Trusted Firmware.
+ */
+
+/* Setting for Keem Bay IO Pad Line Voltage Selection */
+#define ARM_SMCCC_SIP_KEEMBAY_SET_SD_VOLTAGE \
+ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
+ ARM_SMCCC_SMC_32, \
+ ARM_SMCCC_OWNER_SIP, \
+ 0xFF26)
+
+#define KEEMBAY_SET_1V8_VOLT 1
+#define KEEMBAY_SET_3V3_VOLT 0
+
+#if IS_ENABLED(CONFIG_HAVE_ARM_SMCCC_DISCOVERY)
+static inline int keembay_sd_voltage_selection(int volt)
+{
+ struct arm_smccc_res res;
+
+ arm_smccc_1_1_invoke(ARM_SMCCC_SIP_KEEMBAY_SET_SD_VOLTAGE, volt, &res);
+ if ((int)res.a0 < 0)
+ return -EINVAL;
+
+ return 0;
+}
+#else
+static inline int keembay_sd_voltage_selection(int volt)
+{
+ return -ENODEV;
+}
+#endif
+#endif /* __FIRMWARE_KEEMBAY_SMC_H__ */
--
2.17.1