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
sam_smccc_call(u32 fn,u32 arg0,u32 arg1)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
sam_linux_is_optee_available(void)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
sam_secure_init(void)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