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 11 static 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 17 struct 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 30 bool sam_linux_is_optee_available(void) 31 { 32 /* If optee has been detected, then we are running in normal world */ 33 return optee_available; 34 } 35 36 void __init sam_secure_init(void) 37 { 38 struct device_node *np; 39 40 /* 41 * We only check that the OP-TEE node is present and available. The 42 * OP-TEE kernel driver is not needed for the type of interaction made 43 * with OP-TEE here so the driver's status is not checked. 44 */ 45 np = of_find_node_by_path("/firmware/optee"); 46 if (np && of_device_is_available(np)) 47 optee_available = true; 48 of_node_put(np); 49 50 if (optee_available) 51 pr_info("Running under OP-TEE firmware\n"); 52 } 53