xref: /rk3399_ARM-atf/services/spd/opteed/opteed_common.c (revision 82cb2c1ad9897473743f08437d0a3995bed561b9)
1 /*
2  * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <arch_helpers.h>
8 #include <assert.h>
9 #include <bl_common.h>
10 #include <context_mgmt.h>
11 #include <string.h>
12 #include <utils.h>
13 #include "opteed_private.h"
14 
15 /*******************************************************************************
16  * Given a OPTEE entrypoint info pointer, entry point PC, register width,
17  * cpu id & pointer to a context data structure, this function will
18  * initialize OPTEE context and entry point info for OPTEE.
19  ******************************************************************************/
20 void opteed_init_optee_ep_state(struct entry_point_info *optee_entry_point,
21 				uint32_t rw, uint64_t pc,
22 				optee_context_t *optee_ctx)
23 {
24 	uint32_t ep_attr;
25 
26 	/* Passing a NULL context is a critical programming error */
27 	assert(optee_ctx);
28 	assert(optee_entry_point);
29 	assert(pc);
30 
31 	/* Associate this context with the cpu specified */
32 	optee_ctx->mpidr = read_mpidr_el1();
33 	optee_ctx->state = 0;
34 	set_optee_pstate(optee_ctx->state, OPTEE_PSTATE_OFF);
35 
36 	cm_set_context(&optee_ctx->cpu_ctx, SECURE);
37 
38 	/* initialise an entrypoint to set up the CPU context */
39 	ep_attr = SECURE | EP_ST_ENABLE;
40 	if (read_sctlr_el3() & SCTLR_EE_BIT)
41 		ep_attr |= EP_EE_BIG;
42 	SET_PARAM_HEAD(optee_entry_point, PARAM_EP, VERSION_1, ep_attr);
43 	optee_entry_point->pc = pc;
44 	if (rw == OPTEE_AARCH64)
45 		optee_entry_point->spsr = SPSR_64(MODE_EL1, MODE_SP_ELX,
46 						  DISABLE_ALL_EXCEPTIONS);
47 	else
48 		optee_entry_point->spsr = SPSR_MODE32(MODE32_svc, SPSR_T_ARM,
49 						      SPSR_E_LITTLE,
50 						      DAIF_FIQ_BIT |
51 							DAIF_IRQ_BIT |
52 							DAIF_ABT_BIT);
53 	zeromem(&optee_entry_point->args, sizeof(optee_entry_point->args));
54 }
55 
56 /*******************************************************************************
57  * This function takes an OPTEE context pointer and:
58  * 1. Applies the S-EL1 system register context from optee_ctx->cpu_ctx.
59  * 2. Saves the current C runtime state (callee saved registers) on the stack
60  *    frame and saves a reference to this state.
61  * 3. Calls el3_exit() so that the EL3 system and general purpose registers
62  *    from the optee_ctx->cpu_ctx are used to enter the OPTEE image.
63  ******************************************************************************/
64 uint64_t opteed_synchronous_sp_entry(optee_context_t *optee_ctx)
65 {
66 	uint64_t rc;
67 
68 	assert(optee_ctx != NULL);
69 	assert(optee_ctx->c_rt_ctx == 0);
70 
71 	/* Apply the Secure EL1 system register context and switch to it */
72 	assert(cm_get_context(SECURE) == &optee_ctx->cpu_ctx);
73 	cm_el1_sysregs_context_restore(SECURE);
74 	cm_set_next_eret_context(SECURE);
75 
76 	rc = opteed_enter_sp(&optee_ctx->c_rt_ctx);
77 #if DEBUG
78 	optee_ctx->c_rt_ctx = 0;
79 #endif
80 
81 	return rc;
82 }
83 
84 
85 /*******************************************************************************
86  * This function takes an OPTEE context pointer and:
87  * 1. Saves the S-EL1 system register context tp optee_ctx->cpu_ctx.
88  * 2. Restores the current C runtime state (callee saved registers) from the
89  *    stack frame using the reference to this state saved in opteed_enter_sp().
90  * 3. It does not need to save any general purpose or EL3 system register state
91  *    as the generic smc entry routine should have saved those.
92  ******************************************************************************/
93 void opteed_synchronous_sp_exit(optee_context_t *optee_ctx, uint64_t ret)
94 {
95 	assert(optee_ctx != NULL);
96 	/* Save the Secure EL1 system register context */
97 	assert(cm_get_context(SECURE) == &optee_ctx->cpu_ctx);
98 	cm_el1_sysregs_context_save(SECURE);
99 
100 	assert(optee_ctx->c_rt_ctx != 0);
101 	opteed_exit_sp(optee_ctx->c_rt_ctx, ret);
102 
103 	/* Should never reach here */
104 	assert(0);
105 }
106