sam_secure.c (1064B)
1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * Copyright (C) 2022, Microchip 4 */ 5 6#include <linux/arm-smccc.h> 7#include <linux/of.h> 8 9#include "sam_secure.h" 10 11static bool optee_available; 12 13#define SAM_SIP_SMC_STD_CALL_VAL(func_num) \ 14 ARM_SMCCC_CALL_VAL(ARM_SMCCC_STD_CALL, ARM_SMCCC_SMC_32, \ 15 ARM_SMCCC_OWNER_SIP, (func_num)) 16 17struct arm_smccc_res sam_smccc_call(u32 fn, u32 arg0, u32 arg1) 18{ 19 struct arm_smccc_res res = {.a0 = -1}; 20 21 if (WARN_ON(!optee_available)) 22 return res; 23 24 arm_smccc_smc(SAM_SIP_SMC_STD_CALL_VAL(fn), arg0, arg1, 0, 0, 0, 0, 0, 25 &res); 26 27 return res; 28} 29 30void __init sam_secure_init(void) 31{ 32 struct device_node *np; 33 34 /* 35 * We only check that the OP-TEE node is present and available. The 36 * OP-TEE kernel driver is not needed for the type of interaction made 37 * with OP-TEE here so the driver's status is not checked. 38 */ 39 np = of_find_node_by_path("/firmware/optee"); 40 if (np && of_device_is_available(np)) 41 optee_available = true; 42 of_node_put(np); 43 44 if (optee_available) 45 pr_info("Running under OP-TEE firmware\n"); 46}