xref: /rk3399_ARM-atf/services/spd/tlkd/tlkd_common.c (revision 51faada71a219a8b94cd8d8e423f0f22e9da4d8f)
1 /*
2  * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are met:
6  *
7  * Redistributions of source code must retain the above copyright notice, this
8  * list of conditions and the following disclaimer.
9  *
10  * Redistributions in binary form must reproduce the above copyright notice,
11  * this list of conditions and the following disclaimer in the documentation
12  * and/or other materials provided with the distribution.
13  *
14  * Neither the name of ARM nor the names of its contributors may be used
15  * to endorse or promote products derived from this software without specific
16  * prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include <arch_helpers.h>
32 #include <assert.h>
33 #include <bl_common.h>
34 #include <context_mgmt.h>
35 #include <string.h>
36 #include "tlkd_private.h"
37 
38 #define AT_MASK		3
39 
40 /*******************************************************************************
41  * This function helps the SP to translate NS/S virtual addresses.
42  ******************************************************************************/
43 uint64_t tlkd_va_translate(uintptr_t va, int type)
44 {
45 	uint64_t pa;
46 
47 	if (type & TLK_TRANSLATE_NS_VADDR) {
48 
49 		/* save secure context */
50 		cm_el1_sysregs_context_save(SECURE);
51 
52 		/* restore non-secure context */
53 		cm_el1_sysregs_context_restore(NON_SECURE);
54 
55 		/* switch NS bit to start using 64-bit, non-secure mappings */
56 		write_scr(cm_get_scr_el3(NON_SECURE));
57 		isb();
58 	}
59 
60 	int at = type & AT_MASK;
61 	switch (at) {
62 	case 0:
63 		ats12e1r(va);
64 		break;
65 	case 1:
66 		ats12e1w(va);
67 		break;
68 	case 2:
69 		ats12e0r(va);
70 		break;
71 	case 3:
72 		ats12e0w(va);
73 		break;
74 	default:
75 		assert(0);
76 	}
77 
78 	/* get the (NS/S) physical address */
79 	isb();
80 	pa = read_par_el1();
81 
82 	/* Restore secure state */
83 	if (type & TLK_TRANSLATE_NS_VADDR) {
84 
85 		/* restore secure context */
86 		cm_el1_sysregs_context_restore(SECURE);
87 
88 		/* switch NS bit to start using 32-bit, secure mappings */
89 		write_scr(cm_get_scr_el3(SECURE));
90 		isb();
91 	}
92 
93 	return pa;
94 }
95 
96 /*******************************************************************************
97  * Given a secure payload entrypoint, register width, cpu id & pointer to a
98  * context data structure, this function will create a secure context ready for
99  * programming an entry into the secure payload.
100  ******************************************************************************/
101 void tlkd_init_tlk_ep_state(struct entry_point_info *tlk_entry_point,
102 			    uint32_t rw,
103 			    uint64_t pc,
104 			    tlk_context_t *tlk_ctx)
105 {
106 	uint32_t ep_attr, spsr;
107 
108 	/* Passing a NULL context is a critical programming error */
109 	assert(tlk_ctx);
110 	assert(tlk_entry_point);
111 	assert(pc);
112 
113 	/* Associate this context with the cpu specified */
114 	tlk_ctx->mpidr = read_mpidr_el1();
115 	clr_std_smc_active_flag(tlk_ctx->state);
116 	cm_set_context(&tlk_ctx->cpu_ctx, SECURE);
117 
118 	if (rw == SP_AARCH64)
119 		spsr = SPSR_64(MODE_EL1, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS);
120 	else
121 		spsr = SPSR_MODE32(MODE32_svc,
122 				   SPSR_T_ARM,
123 				   read_sctlr_el3() & SCTLR_EE_BIT,
124 				   DISABLE_ALL_EXCEPTIONS);
125 
126 	/* initialise an entrypoint to set up the CPU context */
127 	ep_attr = SECURE | EP_ST_ENABLE;
128 	if (read_sctlr_el3() & SCTLR_EE_BIT)
129 		ep_attr |= EP_EE_BIG;
130 	SET_PARAM_HEAD(tlk_entry_point, PARAM_EP, VERSION_1, ep_attr);
131 
132 	tlk_entry_point->pc = pc;
133 	tlk_entry_point->spsr = spsr;
134 }
135 
136 /*******************************************************************************
137  * This function takes a TLK context pointer and:
138  * 1. Applies the S-EL1 system register context from tlk_ctx->cpu_ctx.
139  * 2. Saves the current C runtime state (callee saved registers) on the stack
140  *    frame and saves a reference to this state.
141  * 3. Calls el3_exit() so that the EL3 system and general purpose registers
142  *    from the tlk_ctx->cpu_ctx are used to enter the secure payload image.
143  ******************************************************************************/
144 uint64_t tlkd_synchronous_sp_entry(tlk_context_t *tlk_ctx)
145 {
146 	uint64_t rc;
147 
148 	/* Passing a NULL context is a critical programming error */
149 	assert(tlk_ctx);
150 	assert(tlk_ctx->c_rt_ctx == 0);
151 
152 	/* Apply the Secure EL1 system register context and switch to it */
153 	assert(cm_get_context(SECURE) == &tlk_ctx->cpu_ctx);
154 	cm_el1_sysregs_context_restore(SECURE);
155 	cm_set_next_eret_context(SECURE);
156 
157 	rc = tlkd_enter_sp(&tlk_ctx->c_rt_ctx);
158 #if DEBUG
159 	tlk_ctx->c_rt_ctx = 0;
160 #endif
161 
162 	return rc;
163 }
164 
165 /*******************************************************************************
166  * This function takes a TLK context pointer and:
167  * 1. Saves the S-EL1 system register context to tlk_ctx->cpu_ctx.
168  * 2. Restores the current C runtime state (callee saved registers) from the
169  *    stack frame using reference to this state saved in tlkd_enter_sp().
170  * 3. It does not need to save any general purpose or EL3 system register state
171  *    as the generic smc entry routine should have saved those.
172  ******************************************************************************/
173 void tlkd_synchronous_sp_exit(tlk_context_t *tlk_ctx, uint64_t ret)
174 {
175 	/* Passing a NULL context is a critical programming error */
176 	assert(tlk_ctx);
177 
178 	/* Save the Secure EL1 system register context */
179 	assert(cm_get_context(SECURE) == &tlk_ctx->cpu_ctx);
180 	cm_el1_sysregs_context_save(SECURE);
181 
182 	assert(tlk_ctx->c_rt_ctx != 0);
183 	tlkd_exit_sp(tlk_ctx->c_rt_ctx, ret);
184 
185 	/* Should never reach here */
186 	assert(0);
187 }
188