xref: /optee_os/core/arch/arm/sm/sm.c (revision 296403e1a2ce9d3a26123c02c31c8cd50869a5a5)
1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3  * Copyright (c) 2016-2020, Linaro Limited
4  * Copyright (c) 2014, STMicroelectronics International N.V.
5  */
6 #include <arm.h>
7 #include <compiler.h>
8 #include <config.h>
9 #include <kernel/misc.h>
10 #include <kernel/thread.h>
11 #include <platform_config.h>
12 #include <sm/optee_smc.h>
13 #include <sm/sm.h>
14 #include <sm/std_smc.h>
15 #include <string.h>
16 #include "sm_private.h"
17 
18 static void smc_arch_handler(struct thread_smc_args *args)
19 {
20 	uint32_t smc_fid = args->a0;
21 	uint32_t feature_fid = args->a1;
22 
23 	switch (smc_fid) {
24 	case ARM_SMCCC_VERSION:
25 		args->a0 = SMCCC_V_1_1;
26 		break;
27 	case ARM_SMCCC_ARCH_FEATURES:
28 		switch (feature_fid) {
29 		case ARM_SMCCC_VERSION:
30 		case ARM_SMCCC_ARCH_SOC_ID:
31 			args->a0 = ARM_SMCCC_RET_SUCCESS;
32 			break;
33 		default:
34 			args->a0 = ARM_SMCCC_RET_NOT_SUPPORTED;
35 			break;
36 		}
37 		break;
38 	case ARM_SMCCC_ARCH_SOC_ID:
39 		args->a0 = ARM_SMCCC_RET_NOT_SUPPORTED;
40 		break;
41 	case ARM_SMCCC_ARCH_WORKAROUND_1:
42 	case ARM_SMCCC_ARCH_WORKAROUND_2:
43 		args->a0 = ARM_SMCCC_RET_NOT_REQUIRED;
44 		break;
45 	default:
46 		args->a0 = OPTEE_SMC_RETURN_UNKNOWN_FUNCTION;
47 		break;
48 	}
49 }
50 
51 uint32_t sm_from_nsec(struct sm_ctx *ctx)
52 {
53 	uint32_t *nsec_r0 = (uint32_t *)(&ctx->nsec.r0);
54 	struct thread_smc_args *args = (struct thread_smc_args *)nsec_r0;
55 
56 	/*
57 	 * Check that struct sm_ctx has the different parts properly
58 	 * aligned since the stack pointer will be updated to point at
59 	 * different parts of this struct.
60 	 */
61 	COMPILE_TIME_ASSERT(!(offsetof(struct sm_ctx, sec.r0) % 8));
62 	COMPILE_TIME_ASSERT(!(offsetof(struct sm_ctx, nsec.r0) % 8));
63 	COMPILE_TIME_ASSERT(!(sizeof(struct sm_ctx) % 8));
64 
65 #ifdef CFG_SM_PLATFORM_HANDLER
66 	if (sm_platform_handler(ctx) == SM_HANDLER_SMC_HANDLED)
67 		return SM_EXIT_TO_NON_SECURE;
68 #endif
69 
70 	switch (OPTEE_SMC_OWNER_NUM(args->a0)) {
71 	case OPTEE_SMC_OWNER_STANDARD:
72 		if (IS_ENABLED(CFG_PSCI_ARM32)) {
73 			smc_std_handler(args, &ctx->nsec);
74 			return SM_EXIT_TO_NON_SECURE;
75 		}
76 		break;
77 	case OPTEE_SMC_OWNER_ARCH:
78 		smc_arch_handler(args);
79 		return SM_EXIT_TO_NON_SECURE;
80 	default:
81 		break;
82 	}
83 
84 	sm_save_unbanked_regs(&ctx->nsec.ub_regs);
85 	sm_restore_unbanked_regs(&ctx->sec.ub_regs);
86 
87 	memcpy(&ctx->sec.r0, args, sizeof(*args));
88 	if (OPTEE_SMC_IS_FAST_CALL(ctx->sec.r0))
89 		ctx->sec.mon_lr = (uint32_t)&thread_vector_table.fast_smc_entry;
90 	else
91 		ctx->sec.mon_lr = (uint32_t)&thread_vector_table.std_smc_entry;
92 
93 	return SM_EXIT_TO_SECURE;
94 }
95