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 ******************************************************************************/
opteed_init_optee_ep_state(struct entry_point_info * optee_entry_point,uint32_t rw,uint64_t pc,uint64_t pageable_part,uint64_t mem_limit,uint64_t dt_addr,optee_context_t * optee_ctx)20 void opteed_init_optee_ep_state(struct entry_point_info *optee_entry_point,
21 uint32_t rw, uint64_t pc,
22 uint64_t pageable_part, uint64_t mem_limit,
23 uint64_t dt_addr, optee_context_t *optee_ctx)
24 {
25 uint32_t ep_attr;
26
27 /* Passing a NULL context is a critical programming error */
28 assert(optee_ctx);
29 assert(optee_entry_point);
30 assert(pc);
31
32 /* Associate this context with the cpu specified */
33 optee_ctx->mpidr = read_mpidr_el1();
34 optee_ctx->state = 0;
35 set_optee_pstate(optee_ctx->state, OPTEE_PSTATE_OFF);
36
37 cm_set_context(&optee_ctx->cpu_ctx, SECURE);
38
39 /* initialise an entrypoint to set up the CPU context */
40 ep_attr = SECURE | EP_ST_ENABLE;
41 if (read_sctlr_el3() & SCTLR_EE_BIT)
42 ep_attr |= EP_EE_BIG;
43 SET_PARAM_HEAD(optee_entry_point, PARAM_EP, VERSION_1, ep_attr);
44 optee_entry_point->pc = pc;
45 if (rw == OPTEE_AARCH64)
46 optee_entry_point->spsr = SPSR_64(MODE_EL1, MODE_SP_ELX,
47 DISABLE_ALL_EXCEPTIONS);
48 else
49 optee_entry_point->spsr = SPSR_MODE32(MODE32_svc, SPSR_T_ARM,
50 SPSR_E_LITTLE,
51 DAIF_FIQ_BIT |
52 DAIF_IRQ_BIT |
53 DAIF_ABT_BIT);
54 zeromem(&optee_entry_point->args, sizeof(optee_entry_point->args));
55 optee_entry_point->args.arg0 = pageable_part;
56 optee_entry_point->args.arg1 = mem_limit;
57 optee_entry_point->args.arg2 = dt_addr;
58 }
59
60 /*******************************************************************************
61 * This function takes an OPTEE context pointer and:
62 * 1. Applies the S-EL1 system register context from optee_ctx->cpu_ctx.
63 * 2. Saves the current C runtime state (callee saved registers) on the stack
64 * frame and saves a reference to this state.
65 * 3. Calls el3_exit() so that the EL3 system and general purpose registers
66 * from the optee_ctx->cpu_ctx are used to enter the OPTEE image.
67 ******************************************************************************/
opteed_synchronous_sp_entry(optee_context_t * optee_ctx)68 uint64_t opteed_synchronous_sp_entry(optee_context_t *optee_ctx)
69 {
70 uint64_t rc;
71
72 assert(optee_ctx != NULL);
73 assert(optee_ctx->c_rt_ctx == 0);
74
75 /* Apply the Secure EL1 system register context and switch to it */
76 assert(cm_get_context(SECURE) == &optee_ctx->cpu_ctx);
77 cm_el1_sysregs_context_restore(SECURE);
78 cm_set_next_eret_context(SECURE);
79
80 rc = opteed_enter_sp(&optee_ctx->c_rt_ctx);
81 #if DEBUG
82 optee_ctx->c_rt_ctx = 0;
83 #endif
84
85 return rc;
86 }
87
88
89 /*******************************************************************************
90 * This function takes an OPTEE context pointer and:
91 * 1. Saves the S-EL1 system register context tp optee_ctx->cpu_ctx.
92 * 2. Restores the current C runtime state (callee saved registers) from the
93 * stack frame using the reference to this state saved in opteed_enter_sp().
94 * 3. It does not need to save any general purpose or EL3 system register state
95 * as the generic smc entry routine should have saved those.
96 ******************************************************************************/
opteed_synchronous_sp_exit(optee_context_t * optee_ctx,uint64_t ret)97 void opteed_synchronous_sp_exit(optee_context_t *optee_ctx, uint64_t ret)
98 {
99 assert(optee_ctx != NULL);
100 /* Save the Secure EL1 system register context */
101 assert(cm_get_context(SECURE) == &optee_ctx->cpu_ctx);
102 cm_el1_sysregs_context_save(SECURE);
103
104 assert(optee_ctx->c_rt_ctx != 0);
105 opteed_exit_sp(optee_ctx->c_rt_ctx, ret);
106
107 /* Should never reach here */
108 assert(0);
109 }
110