xref: /rk3399_ARM-atf/services/std_svc/rmmd/rmmd_main.c (revision 9b3004cfbffbb79e030af4bc39a55231ded29e85)
1 /*
2  * Copyright (c) 2021, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 #include <errno.h>
9 #include <string.h>
10 
11 #include <arch_helpers.h>
12 #include <arch_features.h>
13 #include <bl31/bl31.h>
14 #include <common/debug.h>
15 #include <common/runtime_svc.h>
16 #include <context.h>
17 #include <lib/el3_runtime/context_mgmt.h>
18 #include <lib/el3_runtime/pubsub.h>
19 #include <lib/gpt_rme/gpt_rme.h>
20 
21 #include <lib/spinlock.h>
22 #include <lib/utils.h>
23 #include <lib/xlat_tables/xlat_tables_v2.h>
24 #include <plat/common/common_def.h>
25 #include <plat/common/platform.h>
26 #include <platform_def.h>
27 #include <services/gtsi_svc.h>
28 #include <services/rmi_svc.h>
29 #include <services/rmmd_svc.h>
30 #include <smccc_helpers.h>
31 #include "rmmd_initial_context.h"
32 #include "rmmd_private.h"
33 
34 /*******************************************************************************
35  * RMM context information.
36  ******************************************************************************/
37 rmmd_rmm_context_t rmm_context[PLATFORM_CORE_COUNT];
38 
39 /*******************************************************************************
40  * RMM entry point information. Discovered on the primary core and reused
41  * on secondary cores.
42  ******************************************************************************/
43 static entry_point_info_t *rmm_ep_info;
44 
45 /*******************************************************************************
46  * Static function declaration.
47  ******************************************************************************/
48 static int32_t rmm_init(void);
49 static uint64_t rmmd_smc_forward(uint32_t smc_fid, uint32_t src_sec_state,
50 					uint32_t dst_sec_state, uint64_t x1,
51 					uint64_t x2, uint64_t x3, uint64_t x4,
52 					void *handle);
53 
54 /*******************************************************************************
55  * This function takes an RMM context pointer and performs a synchronous entry
56  * into it.
57  ******************************************************************************/
58 uint64_t rmmd_rmm_sync_entry(rmmd_rmm_context_t *rmm_ctx)
59 {
60 	uint64_t rc;
61 
62 	assert(rmm_ctx != NULL);
63 
64 	cm_set_context(&(rmm_ctx->cpu_ctx), REALM);
65 
66 	/* Save the current el1/el2 context before loading realm context. */
67 	cm_el1_sysregs_context_save(NON_SECURE);
68 	cm_el2_sysregs_context_save(NON_SECURE);
69 
70 	/* Restore the realm context assigned above */
71 	cm_el1_sysregs_context_restore(REALM);
72 	cm_el2_sysregs_context_restore(REALM);
73 	cm_set_next_eret_context(REALM);
74 
75 	/* Enter RMM */
76 	rc = rmmd_rmm_enter(&rmm_ctx->c_rt_ctx);
77 
78 	/* Save realm context */
79 	cm_el1_sysregs_context_save(REALM);
80 	cm_el2_sysregs_context_save(REALM);
81 
82 	/* Restore the el1/el2 context again. */
83 	cm_el1_sysregs_context_restore(NON_SECURE);
84 	cm_el2_sysregs_context_restore(NON_SECURE);
85 
86 	return rc;
87 }
88 
89 /*******************************************************************************
90  * This function returns to the place where rmmd_rmm_sync_entry() was
91  * called originally.
92  ******************************************************************************/
93 __dead2 void rmmd_rmm_sync_exit(uint64_t rc)
94 {
95 	rmmd_rmm_context_t *ctx = &rmm_context[plat_my_core_pos()];
96 
97 	/* Get context of the RMM in use by this CPU. */
98 	assert(cm_get_context(REALM) == &(ctx->cpu_ctx));
99 
100 	/*
101 	 * The RMMD must have initiated the original request through a
102 	 * synchronous entry into RMM. Jump back to the original C runtime
103 	 * context with the value of rc in x0;
104 	 */
105 	rmmd_rmm_exit(ctx->c_rt_ctx, rc);
106 
107 	panic();
108 }
109 
110 static void rmm_el2_context_init(el2_sysregs_t *regs)
111 {
112 	regs->ctx_regs[CTX_SPSR_EL2 >> 3] = REALM_SPSR_EL2;
113 	regs->ctx_regs[CTX_SCTLR_EL2 >> 3] = SCTLR_EL2_RES1;
114 }
115 
116 /*******************************************************************************
117  * Jump to the RMM for the first time.
118  ******************************************************************************/
119 static int32_t rmm_init(void)
120 {
121 
122 	uint64_t rc;
123 
124 	rmmd_rmm_context_t *ctx = &rmm_context[plat_my_core_pos()];
125 
126 	INFO("RMM init start.\n");
127 	ctx->state = RMM_STATE_RESET;
128 
129 	/* Initialize RMM EL2 context. */
130 	rmm_el2_context_init(&ctx->cpu_ctx.el2_sysregs_ctx);
131 
132 	rc = rmmd_rmm_sync_entry(ctx);
133 	if (rc != 0ULL) {
134 		ERROR("RMM initialisation failed 0x%llx\n", rc);
135 		panic();
136 	}
137 
138 	ctx->state = RMM_STATE_IDLE;
139 	INFO("RMM init end.\n");
140 
141 	return 1;
142 }
143 
144 /*******************************************************************************
145  * Load and read RMM manifest, setup RMM.
146  ******************************************************************************/
147 int rmmd_setup(void)
148 {
149 	uint32_t ep_attr;
150 	unsigned int linear_id = plat_my_core_pos();
151 	rmmd_rmm_context_t *rmm_ctx = &rmm_context[linear_id];
152 
153 	/* Make sure RME is supported. */
154 	assert(get_armv9_2_feat_rme_support() != 0U);
155 
156 	rmm_ep_info = bl31_plat_get_next_image_ep_info(REALM);
157 	if (rmm_ep_info == NULL) {
158 		WARN("No RMM image provided by BL2 boot loader, Booting "
159 		     "device without RMM initialization. SMCs destined for "
160 		     "RMM will return SMC_UNK\n");
161 		return -ENOENT;
162 	}
163 
164 	/* Under no circumstances will this parameter be 0 */
165 	assert(rmm_ep_info->pc == RMM_BASE);
166 
167 	/* Initialise an entrypoint to set up the CPU context */
168 	ep_attr = EP_REALM;
169 	if ((read_sctlr_el3() & SCTLR_EE_BIT) != 0U) {
170 		ep_attr |= EP_EE_BIG;
171 	}
172 
173 	SET_PARAM_HEAD(rmm_ep_info, PARAM_EP, VERSION_1, ep_attr);
174 	rmm_ep_info->spsr = SPSR_64(MODE_EL2,
175 					MODE_SP_ELX,
176 					DISABLE_ALL_EXCEPTIONS);
177 
178 	/* Initialise RMM context with this entry point information */
179 	cm_setup_context(&rmm_ctx->cpu_ctx, rmm_ep_info);
180 
181 	INFO("RMM setup done.\n");
182 
183 	/* Register init function for deferred init.  */
184 	bl31_register_rmm_init(&rmm_init);
185 
186 	return 0;
187 }
188 
189 /*******************************************************************************
190  * Forward SMC to the other security state
191  ******************************************************************************/
192 static uint64_t	rmmd_smc_forward(uint32_t smc_fid, uint32_t src_sec_state,
193 					uint32_t dst_sec_state, uint64_t x1,
194 					uint64_t x2, uint64_t x3, uint64_t x4,
195 					void *handle)
196 {
197 	/* Save incoming security state */
198 	cm_el1_sysregs_context_save(src_sec_state);
199 	cm_el2_sysregs_context_save(src_sec_state);
200 
201 	/* Restore outgoing security state */
202 	cm_el1_sysregs_context_restore(dst_sec_state);
203 	cm_el2_sysregs_context_restore(dst_sec_state);
204 	cm_set_next_eret_context(dst_sec_state);
205 
206 	SMC_RET8(cm_get_context(dst_sec_state), smc_fid, x1, x2, x3, x4,
207 			SMC_GET_GP(handle, CTX_GPREG_X5),
208 			SMC_GET_GP(handle, CTX_GPREG_X6),
209 			SMC_GET_GP(handle, CTX_GPREG_X7));
210 }
211 
212 /*******************************************************************************
213  * This function handles all SMCs in the range reserved for RMI. Each call is
214  * either forwarded to the other security state or handled by the RMM dispatcher
215  ******************************************************************************/
216 uint64_t rmmd_rmi_handler(uint32_t smc_fid, uint64_t x1, uint64_t x2,
217 				uint64_t x3, uint64_t x4, void *cookie,
218 				void *handle, uint64_t flags)
219 {
220 	rmmd_rmm_context_t *ctx = &rmm_context[plat_my_core_pos()];
221 	uint32_t src_sec_state;
222 
223 	/* Determine which security state this SMC originated from */
224 	src_sec_state = caller_sec_state(flags);
225 
226 	/* RMI must not be invoked by the Secure world */
227 	if (src_sec_state == SMC_FROM_SECURE) {
228 		WARN("RMM: RMI invoked by secure world.\n");
229 		SMC_RET1(handle, SMC_UNK);
230 	}
231 
232 	/*
233 	 * Forward an RMI call from the Normal world to the Realm world as it
234 	 * is.
235 	 */
236 	if (src_sec_state == SMC_FROM_NON_SECURE) {
237 		VERBOSE("RMM: RMI call from non-secure world.\n");
238 		return rmmd_smc_forward(smc_fid, NON_SECURE, REALM,
239 					x1, x2, x3, x4, handle);
240 	}
241 
242 	assert(src_sec_state == SMC_FROM_REALM);
243 
244 	switch (smc_fid) {
245 	case RMI_RMM_REQ_COMPLETE:
246 		if (ctx->state == RMM_STATE_RESET) {
247 			VERBOSE("RMM: running rmmd_rmm_sync_exit\n");
248 			rmmd_rmm_sync_exit(x1);
249 		}
250 
251 		return rmmd_smc_forward(x1, REALM, NON_SECURE,
252 					x2, x3, x4, 0, handle);
253 
254 	default:
255 		WARN("RMM: Unsupported RMM call 0x%08x\n", smc_fid);
256 		SMC_RET1(handle, SMC_UNK);
257 	}
258 }
259 
260 /*******************************************************************************
261  * This cpu has been turned on. Enter RMM to initialise R-EL2.  Entry into RMM
262  * is done after initialising minimal architectural state that guarantees safe
263  * execution.
264  ******************************************************************************/
265 static void *rmmd_cpu_on_finish_handler(const void *arg)
266 {
267 	int32_t rc;
268 	uint32_t linear_id = plat_my_core_pos();
269 	rmmd_rmm_context_t *ctx = &rmm_context[linear_id];
270 
271 	ctx->state = RMM_STATE_RESET;
272 
273 	/* Initialise RMM context with this entry point information */
274 	cm_setup_context(&ctx->cpu_ctx, rmm_ep_info);
275 
276 	/* Initialize RMM EL2 context. */
277 	rmm_el2_context_init(&ctx->cpu_ctx.el2_sysregs_ctx);
278 
279 	rc = rmmd_rmm_sync_entry(ctx);
280 	if (rc != 0) {
281 		ERROR("RMM initialisation failed (%d) on CPU%d\n", rc,
282 		      linear_id);
283 		panic();
284 	}
285 
286 	ctx->state = RMM_STATE_IDLE;
287 	return NULL;
288 }
289 
290 /* Subscribe to PSCI CPU on to initialize RMM on secondary */
291 SUBSCRIBE_TO_EVENT(psci_cpu_on_finish, rmmd_cpu_on_finish_handler);
292 
293 static int gtsi_transition_granule(uint64_t pa,
294 					unsigned int src_sec_state,
295 					unsigned int target_pas)
296 {
297 	int ret;
298 
299 	ret = gpt_transition_pas(pa, PAGE_SIZE_4KB, src_sec_state, target_pas);
300 
301 	/* Convert TF-A error codes into GTSI error codes */
302 	if (ret == -EINVAL) {
303 		ERROR("[GTSI] Transition failed: invalid %s\n", "address");
304 		ERROR("       PA: 0x%llx, SRC: %d, PAS: %d\n", pa,
305 		      src_sec_state, target_pas);
306 		ret = GRAN_TRANS_RET_BAD_ADDR;
307 	} else if (ret == -EPERM) {
308 		ERROR("[GTSI] Transition failed: invalid %s\n", "caller/PAS");
309 		ERROR("       PA: 0x%llx, SRC: %d, PAS: %d\n", pa,
310 		      src_sec_state, target_pas);
311 		ret = GRAN_TRANS_RET_BAD_PAS;
312 	}
313 
314 	return ret;
315 }
316 
317 /*******************************************************************************
318  * This function handles all SMCs in the range reserved for GTF.
319  ******************************************************************************/
320 uint64_t rmmd_gtsi_handler(uint32_t smc_fid, uint64_t x1, uint64_t x2,
321 				uint64_t x3, uint64_t x4, void *cookie,
322 				void *handle, uint64_t flags)
323 {
324 	uint32_t src_sec_state;
325 
326 	/* Determine which security state this SMC originated from */
327 	src_sec_state = caller_sec_state(flags);
328 
329 	if (src_sec_state != SMC_FROM_REALM) {
330 		WARN("RMM: GTF call originated from secure or normal world\n");
331 		SMC_RET1(handle, SMC_UNK);
332 	}
333 
334 	switch (smc_fid) {
335 	case SMC_ASC_MARK_REALM:
336 		SMC_RET1(handle, gtsi_transition_granule(x1, SMC_FROM_REALM,
337 								GPT_GPI_REALM));
338 	case SMC_ASC_MARK_NONSECURE:
339 		SMC_RET1(handle, gtsi_transition_granule(x1, SMC_FROM_REALM,
340 								GPT_GPI_NS));
341 	default:
342 		WARN("RMM: Unsupported GTF call 0x%08x\n", smc_fid);
343 		SMC_RET1(handle, SMC_UNK);
344 	}
345 }
346