xref: /rk3399_ARM-atf/services/std_svc/rmmd/rmmd_main.c (revision 8c980a4a468aeabb9e49875fec395c625a0c2b2b)
1 /*
2  * Copyright (c) 2021-2022, 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 <inttypes.h>
10 #include <stdint.h>
11 #include <string.h>
12 
13 #include <arch_helpers.h>
14 #include <arch_features.h>
15 #include <bl31/bl31.h>
16 #include <common/debug.h>
17 #include <common/runtime_svc.h>
18 #include <context.h>
19 #include <lib/el3_runtime/context_mgmt.h>
20 #include <lib/el3_runtime/pubsub.h>
21 #include <lib/gpt_rme/gpt_rme.h>
22 
23 #include <lib/spinlock.h>
24 #include <lib/utils.h>
25 #include <lib/xlat_tables/xlat_tables_v2.h>
26 #include <plat/common/common_def.h>
27 #include <plat/common/platform.h>
28 #include <platform_def.h>
29 #include <services/rmmd_svc.h>
30 #include <smccc_helpers.h>
31 #include <lib/extensions/sve.h>
32 #include "rmmd_initial_context.h"
33 #include "rmmd_private.h"
34 
35 /*******************************************************************************
36  * RMM <-> EL3 shared buffer information.
37  ******************************************************************************/
38 static size_t shared_buf_size;
39 static uintptr_t shared_buf_base;
40 
41 /*******************************************************************************
42  * RMM boot failure flag
43  ******************************************************************************/
44 static bool rmm_boot_failed;
45 
46 /*******************************************************************************
47  * RMM context information.
48  ******************************************************************************/
49 rmmd_rmm_context_t rmm_context[PLATFORM_CORE_COUNT];
50 
51 /*******************************************************************************
52  * RMM entry point information. Discovered on the primary core and reused
53  * on secondary cores.
54  ******************************************************************************/
55 static entry_point_info_t *rmm_ep_info;
56 
57 /*******************************************************************************
58  * Static function declaration.
59  ******************************************************************************/
60 static int32_t rmm_init(void);
61 
62 /*******************************************************************************
63  * This function takes an RMM context pointer and performs a synchronous entry
64  * into it.
65  ******************************************************************************/
66 uint64_t rmmd_rmm_sync_entry(rmmd_rmm_context_t *rmm_ctx)
67 {
68 	uint64_t rc;
69 
70 	assert(rmm_ctx != NULL);
71 
72 	cm_set_context(&(rmm_ctx->cpu_ctx), REALM);
73 
74 	/* Restore the realm context assigned above */
75 	cm_el1_sysregs_context_restore(REALM);
76 	cm_el2_sysregs_context_restore(REALM);
77 	cm_set_next_eret_context(REALM);
78 
79 	/* Enter RMM */
80 	rc = rmmd_rmm_enter(&rmm_ctx->c_rt_ctx);
81 
82 	/*
83 	 * Save realm context. EL1 and EL2 Non-secure
84 	 * contexts will be restored before exiting to
85 	 * Non-secure world, therefore there is no need
86 	 * to clear EL1 and EL2 context registers.
87 	 */
88 	cm_el1_sysregs_context_save(REALM);
89 	cm_el2_sysregs_context_save(REALM);
90 
91 	return rc;
92 }
93 
94 /*******************************************************************************
95  * This function returns to the place where rmmd_rmm_sync_entry() was
96  * called originally.
97  ******************************************************************************/
98 __dead2 void rmmd_rmm_sync_exit(uint64_t rc)
99 {
100 	rmmd_rmm_context_t *ctx = &rmm_context[plat_my_core_pos()];
101 
102 	/* Get context of the RMM in use by this CPU. */
103 	assert(cm_get_context(REALM) == &(ctx->cpu_ctx));
104 
105 	/*
106 	 * The RMMD must have initiated the original request through a
107 	 * synchronous entry into RMM. Jump back to the original C runtime
108 	 * context with the value of rc in x0;
109 	 */
110 	rmmd_rmm_exit(ctx->c_rt_ctx, rc);
111 
112 	panic();
113 }
114 
115 static void rmm_el2_context_init(el2_sysregs_t *regs)
116 {
117 	regs->ctx_regs[CTX_SPSR_EL2 >> 3] = REALM_SPSR_EL2;
118 	regs->ctx_regs[CTX_SCTLR_EL2 >> 3] = SCTLR_EL2_RES1;
119 }
120 
121 /*******************************************************************************
122  * Enable architecture extensions on first entry to Realm world.
123  ******************************************************************************/
124 static void manage_extensions_realm(cpu_context_t *ctx)
125 {
126 #if ENABLE_SVE_FOR_NS
127 	/*
128 	 * Enable SVE and FPU in realm context when it is enabled for NS.
129 	 * Realm manager must ensure that the SVE and FPU register
130 	 * contexts are properly managed.
131 	 */
132 	sve_enable(ctx);
133 #else
134 	/*
135 	 * Disable SVE and FPU in realm context when it is disabled for NS.
136 	 */
137 	sve_disable(ctx);
138 #endif /* ENABLE_SVE_FOR_NS */
139 }
140 
141 /*******************************************************************************
142  * Jump to the RMM for the first time.
143  ******************************************************************************/
144 static int32_t rmm_init(void)
145 {
146 	long rc;
147 	rmmd_rmm_context_t *ctx = &rmm_context[plat_my_core_pos()];
148 
149 	INFO("RMM init start.\n");
150 
151 	/* Enable architecture extensions */
152 	manage_extensions_realm(&ctx->cpu_ctx);
153 
154 	/* Initialize RMM EL2 context. */
155 	rmm_el2_context_init(&ctx->cpu_ctx.el2_sysregs_ctx);
156 
157 	rc = rmmd_rmm_sync_entry(ctx);
158 	if (rc != E_RMM_BOOT_SUCCESS) {
159 		ERROR("RMM init failed: %ld\n", rc);
160 		/* Mark the boot as failed for all the CPUs */
161 		rmm_boot_failed = true;
162 		return 0;
163 	}
164 
165 	INFO("RMM init end.\n");
166 
167 	return 1;
168 }
169 
170 /*******************************************************************************
171  * Load and read RMM manifest, setup RMM.
172  ******************************************************************************/
173 int rmmd_setup(void)
174 {
175 	uint32_t ep_attr;
176 	unsigned int linear_id = plat_my_core_pos();
177 	rmmd_rmm_context_t *rmm_ctx = &rmm_context[linear_id];
178 
179 	/* Make sure RME is supported. */
180 	assert(get_armv9_2_feat_rme_support() != 0U);
181 
182 	rmm_ep_info = bl31_plat_get_next_image_ep_info(REALM);
183 	if (rmm_ep_info == NULL) {
184 		WARN("No RMM image provided by BL2 boot loader, Booting "
185 		     "device without RMM initialization. SMCs destined for "
186 		     "RMM will return SMC_UNK\n");
187 		return -ENOENT;
188 	}
189 
190 	/* Under no circumstances will this parameter be 0 */
191 	assert(rmm_ep_info->pc == RMM_BASE);
192 
193 	/* Initialise an entrypoint to set up the CPU context */
194 	ep_attr = EP_REALM;
195 	if ((read_sctlr_el3() & SCTLR_EE_BIT) != 0U) {
196 		ep_attr |= EP_EE_BIG;
197 	}
198 
199 	SET_PARAM_HEAD(rmm_ep_info, PARAM_EP, VERSION_1, ep_attr);
200 	rmm_ep_info->spsr = SPSR_64(MODE_EL2,
201 					MODE_SP_ELX,
202 					DISABLE_ALL_EXCEPTIONS);
203 
204 	shared_buf_size =
205 			plat_rmmd_get_el3_rmm_shared_mem(&shared_buf_base);
206 
207 	assert((shared_buf_size == SZ_4K) &&
208 					((void *)shared_buf_base != NULL));
209 
210 	/*
211 	 * Prepare coldboot arguments for RMM:
212 	 * arg0: This CPUID (primary processor).
213 	 * arg1: Version for this Boot Interface.
214 	 * arg2: PLATFORM_CORE_COUNT.
215 	 * arg3: Base address for the EL3 <-> RMM shared area. The boot
216 	 *       manifest will be stored at the beginning of this area.
217 	 */
218 	rmm_ep_info->args.arg0 = linear_id;
219 	rmm_ep_info->args.arg1 = RMM_EL3_INTERFACE_VERSION;
220 	rmm_ep_info->args.arg2 = PLATFORM_CORE_COUNT;
221 	rmm_ep_info->args.arg3 = shared_buf_base;
222 
223 	/* Initialise RMM context with this entry point information */
224 	cm_setup_context(&rmm_ctx->cpu_ctx, rmm_ep_info);
225 
226 	INFO("RMM setup done.\n");
227 
228 	/* Register init function for deferred init.  */
229 	bl31_register_rmm_init(&rmm_init);
230 
231 	return 0;
232 }
233 
234 /*******************************************************************************
235  * Forward SMC to the other security state
236  ******************************************************************************/
237 static uint64_t	rmmd_smc_forward(uint32_t src_sec_state,
238 					uint32_t dst_sec_state, uint64_t x0,
239 					uint64_t x1, uint64_t x2, uint64_t x3,
240 					uint64_t x4, void *handle)
241 {
242 	/* Save incoming security state */
243 	cm_el1_sysregs_context_save(src_sec_state);
244 	cm_el2_sysregs_context_save(src_sec_state);
245 
246 	/* Restore outgoing security state */
247 	cm_el1_sysregs_context_restore(dst_sec_state);
248 	cm_el2_sysregs_context_restore(dst_sec_state);
249 	cm_set_next_eret_context(dst_sec_state);
250 
251 	/*
252 	 * As per SMCCCv1.1, we need to preserve x4 to x7 unless
253 	 * being used as return args. Hence we differentiate the
254 	 * onward and backward path. Support upto 8 args in the
255 	 * onward path and 4 args in return path.
256 	 */
257 	if (src_sec_state == NON_SECURE) {
258 		SMC_RET8(cm_get_context(dst_sec_state), x0, x1, x2, x3, x4,
259 				SMC_GET_GP(handle, CTX_GPREG_X5),
260 				SMC_GET_GP(handle, CTX_GPREG_X6),
261 				SMC_GET_GP(handle, CTX_GPREG_X7));
262 	} else {
263 		SMC_RET4(cm_get_context(dst_sec_state), x0, x1, x2, x3);
264 	}
265 }
266 
267 /*******************************************************************************
268  * This function handles all SMCs in the range reserved for RMI. Each call is
269  * either forwarded to the other security state or handled by the RMM dispatcher
270  ******************************************************************************/
271 uint64_t rmmd_rmi_handler(uint32_t smc_fid, uint64_t x1, uint64_t x2,
272 				uint64_t x3, uint64_t x4, void *cookie,
273 				void *handle, uint64_t flags)
274 {
275 	uint32_t src_sec_state;
276 
277 	/* If RMM failed to boot, treat any RMI SMC as unknown */
278 	if (rmm_boot_failed) {
279 		WARN("RMMD: Failed to boot up RMM. Ignoring RMI call\n");
280 		SMC_RET1(handle, SMC_UNK);
281 	}
282 
283 	/* Determine which security state this SMC originated from */
284 	src_sec_state = caller_sec_state(flags);
285 
286 	/* RMI must not be invoked by the Secure world */
287 	if (src_sec_state == SMC_FROM_SECURE) {
288 		WARN("RMMD: RMI invoked by secure world.\n");
289 		SMC_RET1(handle, SMC_UNK);
290 	}
291 
292 	/*
293 	 * Forward an RMI call from the Normal world to the Realm world as it
294 	 * is.
295 	 */
296 	if (src_sec_state == SMC_FROM_NON_SECURE) {
297 		VERBOSE("RMMD: RMI call from non-secure world.\n");
298 		return rmmd_smc_forward(NON_SECURE, REALM, smc_fid,
299 					x1, x2, x3, x4, handle);
300 	}
301 
302 	if (src_sec_state != SMC_FROM_REALM) {
303 		SMC_RET1(handle, SMC_UNK);
304 	}
305 
306 	switch (smc_fid) {
307 	case RMMD_RMI_REQ_COMPLETE:
308 		return rmmd_smc_forward(REALM, NON_SECURE, x1,
309 					x2, x3, x4, 0, handle);
310 
311 	default:
312 		WARN("RMMD: Unsupported RMM call 0x%08x\n", smc_fid);
313 		SMC_RET1(handle, SMC_UNK);
314 	}
315 }
316 
317 /*******************************************************************************
318  * This cpu has been turned on. Enter RMM to initialise R-EL2.  Entry into RMM
319  * is done after initialising minimal architectural state that guarantees safe
320  * execution.
321  ******************************************************************************/
322 static void *rmmd_cpu_on_finish_handler(const void *arg)
323 {
324 	long rc;
325 	uint32_t linear_id = plat_my_core_pos();
326 	rmmd_rmm_context_t *ctx = &rmm_context[linear_id];
327 
328 	if (rmm_boot_failed) {
329 		/* RMM Boot failed on a previous CPU. Abort. */
330 		ERROR("RMM Failed to initialize. Ignoring for CPU%d\n",
331 								linear_id);
332 		return NULL;
333 	}
334 
335 	/*
336 	 * Prepare warmboot arguments for RMM:
337 	 * arg0: This CPUID.
338 	 * arg1 to arg3: Not used.
339 	 */
340 	rmm_ep_info->args.arg0 = linear_id;
341 	rmm_ep_info->args.arg1 = 0ULL;
342 	rmm_ep_info->args.arg2 = 0ULL;
343 	rmm_ep_info->args.arg3 = 0ULL;
344 
345 	/* Initialise RMM context with this entry point information */
346 	cm_setup_context(&ctx->cpu_ctx, rmm_ep_info);
347 
348 	/* Enable architecture extensions */
349 	manage_extensions_realm(&ctx->cpu_ctx);
350 
351 	/* Initialize RMM EL2 context. */
352 	rmm_el2_context_init(&ctx->cpu_ctx.el2_sysregs_ctx);
353 
354 	rc = rmmd_rmm_sync_entry(ctx);
355 
356 	if (rc != E_RMM_BOOT_SUCCESS) {
357 		ERROR("RMM init failed on CPU%d: %ld\n", linear_id, rc);
358 		/* Mark the boot as failed for any other booting CPU */
359 		rmm_boot_failed = true;
360 	}
361 
362 	return NULL;
363 }
364 
365 /* Subscribe to PSCI CPU on to initialize RMM on secondary */
366 SUBSCRIBE_TO_EVENT(psci_cpu_on_finish, rmmd_cpu_on_finish_handler);
367 
368 /* Convert GPT lib error to RMMD GTS error */
369 static int gpt_to_gts_error(int error, uint32_t smc_fid, uint64_t address)
370 {
371 	int ret;
372 
373 	if (error == 0) {
374 		return RMMD_OK;
375 	}
376 
377 	if (error == -EINVAL) {
378 		ret = RMMD_ERR_BAD_ADDR;
379 	} else {
380 		/* This is the only other error code we expect */
381 		assert(error == -EPERM);
382 		ret = RMMD_ERR_BAD_PAS;
383 	}
384 
385 	ERROR("RMMD: PAS Transition failed. GPT ret = %d, PA: 0x%"PRIx64 ", FID = 0x%x\n",
386 				error, address, smc_fid);
387 	return ret;
388 }
389 
390 /*******************************************************************************
391  * This function handles RMM-EL3 interface SMCs
392  ******************************************************************************/
393 uint64_t rmmd_rmm_el3_handler(uint32_t smc_fid, uint64_t x1, uint64_t x2,
394 				uint64_t x3, uint64_t x4, void *cookie,
395 				void *handle, uint64_t flags)
396 {
397 	uint32_t src_sec_state;
398 	int ret;
399 
400 	/* If RMM failed to boot, treat any RMM-EL3 interface SMC as unknown */
401 	if (rmm_boot_failed) {
402 		WARN("RMMD: Failed to boot up RMM. Ignoring RMM-EL3 call\n");
403 		SMC_RET1(handle, SMC_UNK);
404 	}
405 
406 	/* Determine which security state this SMC originated from */
407 	src_sec_state = caller_sec_state(flags);
408 
409 	if (src_sec_state != SMC_FROM_REALM) {
410 		WARN("RMMD: RMM-EL3 call originated from secure or normal world\n");
411 		SMC_RET1(handle, SMC_UNK);
412 	}
413 
414 	switch (smc_fid) {
415 	case RMMD_GTSI_DELEGATE:
416 		ret = gpt_delegate_pas(x1, PAGE_SIZE_4KB, SMC_FROM_REALM);
417 		SMC_RET1(handle, gpt_to_gts_error(ret, smc_fid, x1));
418 	case RMMD_GTSI_UNDELEGATE:
419 		ret = gpt_undelegate_pas(x1, PAGE_SIZE_4KB, SMC_FROM_REALM);
420 		SMC_RET1(handle, gpt_to_gts_error(ret, smc_fid, x1));
421 	case RMMD_ATTEST_GET_PLAT_TOKEN:
422 		ret = rmmd_attest_get_platform_token(x1, &x2, x3);
423 		SMC_RET2(handle, ret, x2);
424 	case RMMD_ATTEST_GET_REALM_KEY:
425 		ret = rmmd_attest_get_signing_key(x1, &x2, x3);
426 		SMC_RET2(handle, ret, x2);
427 
428 	case RMM_BOOT_COMPLETE:
429 		VERBOSE("RMMD: running rmmd_rmm_sync_exit\n");
430 		rmmd_rmm_sync_exit(x1);
431 
432 	default:
433 		WARN("RMMD: Unsupported RMM-EL3 call 0x%08x\n", smc_fid);
434 		SMC_RET1(handle, SMC_UNK);
435 	}
436 }
437