xref: /rk3399_ARM-atf/lib/el3_runtime/aarch64/context_mgmt.c (revision 99506face112410ae37cf617b6efa809b4eee0ee)
1 /*
2  * Copyright (c) 2013-2023, Arm Limited and Contributors. All rights reserved.
3  * Copyright (c) 2022, NVIDIA Corporation. All rights reserved.
4  *
5  * SPDX-License-Identifier: BSD-3-Clause
6  */
7 
8 #include <assert.h>
9 #include <stdbool.h>
10 #include <string.h>
11 
12 #include <platform_def.h>
13 
14 #include <arch.h>
15 #include <arch_helpers.h>
16 #include <arch_features.h>
17 #include <bl31/interrupt_mgmt.h>
18 #include <common/bl_common.h>
19 #include <common/debug.h>
20 #include <context.h>
21 #include <drivers/arm/gicv3.h>
22 #include <lib/el3_runtime/context_mgmt.h>
23 #include <lib/el3_runtime/pubsub_events.h>
24 #include <lib/extensions/amu.h>
25 #include <lib/extensions/brbe.h>
26 #include <lib/extensions/mpam.h>
27 #include <lib/extensions/pmuv3.h>
28 #include <lib/extensions/sme.h>
29 #include <lib/extensions/spe.h>
30 #include <lib/extensions/sve.h>
31 #include <lib/extensions/sys_reg_trace.h>
32 #include <lib/extensions/trbe.h>
33 #include <lib/extensions/trf.h>
34 #include <lib/utils.h>
35 
36 #if ENABLE_FEAT_TWED
37 /* Make sure delay value fits within the range(0-15) */
38 CASSERT(((TWED_DELAY & ~SCR_TWEDEL_MASK) == 0U), assert_twed_delay_value_check);
39 #endif /* ENABLE_FEAT_TWED */
40 
41 static void manage_extensions_nonsecure(cpu_context_t *ctx);
42 static void manage_extensions_secure(cpu_context_t *ctx);
43 
44 static void setup_el1_context(cpu_context_t *ctx, const struct entry_point_info *ep)
45 {
46 	u_register_t sctlr_elx, actlr_elx;
47 
48 	/*
49 	 * Initialise SCTLR_EL1 to the reset value corresponding to the target
50 	 * execution state setting all fields rather than relying on the hw.
51 	 * Some fields have architecturally UNKNOWN reset values and these are
52 	 * set to zero.
53 	 *
54 	 * SCTLR.EE: Endianness is taken from the entrypoint attributes.
55 	 *
56 	 * SCTLR.M, SCTLR.C and SCTLR.I: These fields must be zero (as
57 	 * required by PSCI specification)
58 	 */
59 	sctlr_elx = (EP_GET_EE(ep->h.attr) != 0U) ? SCTLR_EE_BIT : 0UL;
60 	if (GET_RW(ep->spsr) == MODE_RW_64) {
61 		sctlr_elx |= SCTLR_EL1_RES1;
62 	} else {
63 		/*
64 		 * If the target execution state is AArch32 then the following
65 		 * fields need to be set.
66 		 *
67 		 * SCTRL_EL1.nTWE: Set to one so that EL0 execution of WFE
68 		 *  instructions are not trapped to EL1.
69 		 *
70 		 * SCTLR_EL1.nTWI: Set to one so that EL0 execution of WFI
71 		 *  instructions are not trapped to EL1.
72 		 *
73 		 * SCTLR_EL1.CP15BEN: Set to one to enable EL0 execution of the
74 		 *  CP15DMB, CP15DSB, and CP15ISB instructions.
75 		 */
76 		sctlr_elx |= SCTLR_AARCH32_EL1_RES1 | SCTLR_CP15BEN_BIT
77 					| SCTLR_NTWI_BIT | SCTLR_NTWE_BIT;
78 	}
79 
80 #if ERRATA_A75_764081
81 	/*
82 	 * If workaround of errata 764081 for Cortex-A75 is used then set
83 	 * SCTLR_EL1.IESB to enable Implicit Error Synchronization Barrier.
84 	 */
85 	sctlr_elx |= SCTLR_IESB_BIT;
86 #endif
87 	/* Store the initialised SCTLR_EL1 value in the cpu_context */
88 	write_ctx_reg(get_el1_sysregs_ctx(ctx), CTX_SCTLR_EL1, sctlr_elx);
89 
90 	/*
91 	 * Base the context ACTLR_EL1 on the current value, as it is
92 	 * implementation defined. The context restore process will write
93 	 * the value from the context to the actual register and can cause
94 	 * problems for processor cores that don't expect certain bits to
95 	 * be zero.
96 	 */
97 	actlr_elx = read_actlr_el1();
98 	write_ctx_reg((get_el1_sysregs_ctx(ctx)), (CTX_ACTLR_EL1), (actlr_elx));
99 }
100 
101 /******************************************************************************
102  * This function performs initializations that are specific to SECURE state
103  * and updates the cpu context specified by 'ctx'.
104  *****************************************************************************/
105 static void setup_secure_context(cpu_context_t *ctx, const struct entry_point_info *ep)
106 {
107 	u_register_t scr_el3;
108 	el3_state_t *state;
109 
110 	state = get_el3state_ctx(ctx);
111 	scr_el3 = read_ctx_reg(state, CTX_SCR_EL3);
112 
113 #if defined(IMAGE_BL31) && !defined(SPD_spmd)
114 	/*
115 	 * SCR_EL3.IRQ, SCR_EL3.FIQ: Enable the physical FIQ and IRQ routing as
116 	 * indicated by the interrupt routing model for BL31.
117 	 */
118 	scr_el3 |= get_scr_el3_from_routing_model(SECURE);
119 #endif
120 
121 #if !CTX_INCLUDE_MTE_REGS || ENABLE_ASSERTIONS
122 	/* Get Memory Tagging Extension support level */
123 	unsigned int mte = get_armv8_5_mte_support();
124 #endif
125 	/*
126 	 * Allow access to Allocation Tags when CTX_INCLUDE_MTE_REGS
127 	 * is set, or when MTE is only implemented at EL0.
128 	 */
129 #if CTX_INCLUDE_MTE_REGS
130 	assert((mte == MTE_IMPLEMENTED_ELX) || (mte == MTE_IMPLEMENTED_ASY));
131 	scr_el3 |= SCR_ATA_BIT;
132 #else
133 	if (mte == MTE_IMPLEMENTED_EL0) {
134 		scr_el3 |= SCR_ATA_BIT;
135 	}
136 #endif /* CTX_INCLUDE_MTE_REGS */
137 
138 	/* Enable S-EL2 if the next EL is EL2 and S-EL2 is present */
139 	if ((GET_EL(ep->spsr) == MODE_EL2) && is_feat_sel2_supported()) {
140 		if (GET_RW(ep->spsr) != MODE_RW_64) {
141 			ERROR("S-EL2 can not be used in AArch32\n.");
142 			panic();
143 		}
144 
145 		scr_el3 |= SCR_EEL2_BIT;
146 	}
147 
148 	write_ctx_reg(state, CTX_SCR_EL3, scr_el3);
149 
150 	/*
151 	 * Initialize EL1 context registers unless SPMC is running
152 	 * at S-EL2.
153 	 */
154 #if !SPMD_SPM_AT_SEL2
155 	setup_el1_context(ctx, ep);
156 #endif
157 
158 	manage_extensions_secure(ctx);
159 }
160 
161 #if ENABLE_RME
162 /******************************************************************************
163  * This function performs initializations that are specific to REALM state
164  * and updates the cpu context specified by 'ctx'.
165  *****************************************************************************/
166 static void setup_realm_context(cpu_context_t *ctx, const struct entry_point_info *ep)
167 {
168 	u_register_t scr_el3;
169 	el3_state_t *state;
170 
171 	state = get_el3state_ctx(ctx);
172 	scr_el3 = read_ctx_reg(state, CTX_SCR_EL3);
173 
174 	scr_el3 |= SCR_NS_BIT | SCR_NSE_BIT;
175 
176 	if (is_feat_csv2_2_supported()) {
177 		/* Enable access to the SCXTNUM_ELx registers. */
178 		scr_el3 |= SCR_EnSCXT_BIT;
179 	}
180 
181 	write_ctx_reg(state, CTX_SCR_EL3, scr_el3);
182 }
183 #endif /* ENABLE_RME */
184 
185 /******************************************************************************
186  * This function performs initializations that are specific to NON-SECURE state
187  * and updates the cpu context specified by 'ctx'.
188  *****************************************************************************/
189 static void setup_ns_context(cpu_context_t *ctx, const struct entry_point_info *ep)
190 {
191 	u_register_t scr_el3;
192 	el3_state_t *state;
193 
194 	state = get_el3state_ctx(ctx);
195 	scr_el3 = read_ctx_reg(state, CTX_SCR_EL3);
196 
197 	/* SCR_NS: Set the NS bit */
198 	scr_el3 |= SCR_NS_BIT;
199 
200 #if !CTX_INCLUDE_PAUTH_REGS
201 	/*
202 	 * If the pointer authentication registers aren't saved during world
203 	 * switches the value of the registers can be leaked from the Secure to
204 	 * the Non-secure world. To prevent this, rather than enabling pointer
205 	 * authentication everywhere, we only enable it in the Non-secure world.
206 	 *
207 	 * If the Secure world wants to use pointer authentication,
208 	 * CTX_INCLUDE_PAUTH_REGS must be set to 1.
209 	 */
210 	scr_el3 |= SCR_API_BIT | SCR_APK_BIT;
211 #endif /* !CTX_INCLUDE_PAUTH_REGS */
212 
213 	/* Allow access to Allocation Tags when MTE is implemented. */
214 	scr_el3 |= SCR_ATA_BIT;
215 
216 #if HANDLE_EA_EL3_FIRST_NS
217 	/* SCR_EL3.EA: Route External Abort and SError Interrupt to EL3. */
218 	scr_el3 |= SCR_EA_BIT;
219 #endif
220 
221 #if RAS_TRAP_NS_ERR_REC_ACCESS
222 	/*
223 	 * SCR_EL3.TERR: Trap Error record accesses. Accesses to the RAS ERR
224 	 * and RAS ERX registers from EL1 and EL2(from any security state)
225 	 * are trapped to EL3.
226 	 * Set here to trap only for NS EL1/EL2
227 	 *
228 	 */
229 	scr_el3 |= SCR_TERR_BIT;
230 #endif
231 
232 	if (is_feat_csv2_2_supported()) {
233 		/* Enable access to the SCXTNUM_ELx registers. */
234 		scr_el3 |= SCR_EnSCXT_BIT;
235 	}
236 
237 #ifdef IMAGE_BL31
238 	/*
239 	 * SCR_EL3.IRQ, SCR_EL3.FIQ: Enable the physical FIQ and IRQ routing as
240 	 *  indicated by the interrupt routing model for BL31.
241 	 */
242 	scr_el3 |= get_scr_el3_from_routing_model(NON_SECURE);
243 #endif
244 	write_ctx_reg(state, CTX_SCR_EL3, scr_el3);
245 
246 	/* Initialize EL1 context registers */
247 	setup_el1_context(ctx, ep);
248 
249 	/* Initialize EL2 context registers */
250 #if CTX_INCLUDE_EL2_REGS
251 
252 	/*
253 	 * Initialize SCTLR_EL2 context register using Endianness value
254 	 * taken from the entrypoint attribute.
255 	 */
256 	u_register_t sctlr_el2 = (EP_GET_EE(ep->h.attr) != 0U) ? SCTLR_EE_BIT : 0UL;
257 	sctlr_el2 |= SCTLR_EL2_RES1;
258 	write_ctx_reg(get_el2_sysregs_ctx(ctx), CTX_SCTLR_EL2,
259 			sctlr_el2);
260 
261 	/*
262 	 * Program the ICC_SRE_EL2 to make sure the correct bits are set
263 	 * when restoring NS context.
264 	 */
265 	u_register_t icc_sre_el2 = ICC_SRE_DIB_BIT | ICC_SRE_DFB_BIT |
266 				   ICC_SRE_EN_BIT | ICC_SRE_SRE_BIT;
267 	write_ctx_reg(get_el2_sysregs_ctx(ctx), CTX_ICC_SRE_EL2,
268 			icc_sre_el2);
269 
270 	if (is_feat_hcx_supported()) {
271 		/*
272 		 * Initialize register HCRX_EL2 with its init value.
273 		 * As the value of HCRX_EL2 is UNKNOWN on reset, there is a
274 		 * chance that this can lead to unexpected behavior in lower
275 		 * ELs that have not been updated since the introduction of
276 		 * this feature if not properly initialized, especially when
277 		 * it comes to those bits that enable/disable traps.
278 		 */
279 		write_ctx_reg(get_el2_sysregs_ctx(ctx), CTX_HCRX_EL2,
280 			HCRX_EL2_INIT_VAL);
281 	}
282 #endif /* CTX_INCLUDE_EL2_REGS */
283 
284 	manage_extensions_nonsecure(ctx);
285 }
286 
287 /*******************************************************************************
288  * The following function performs initialization of the cpu_context 'ctx'
289  * for first use that is common to all security states, and sets the
290  * initial entrypoint state as specified by the entry_point_info structure.
291  *
292  * The EE and ST attributes are used to configure the endianness and secure
293  * timer availability for the new execution context.
294  ******************************************************************************/
295 static void setup_context_common(cpu_context_t *ctx, const entry_point_info_t *ep)
296 {
297 	u_register_t scr_el3;
298 	el3_state_t *state;
299 	gp_regs_t *gp_regs;
300 
301 	/* Clear any residual register values from the context */
302 	zeromem(ctx, sizeof(*ctx));
303 
304 	/*
305 	 * SCR_EL3 was initialised during reset sequence in macro
306 	 * el3_arch_init_common. This code modifies the SCR_EL3 fields that
307 	 * affect the next EL.
308 	 *
309 	 * The following fields are initially set to zero and then updated to
310 	 * the required value depending on the state of the SPSR_EL3 and the
311 	 * Security state and entrypoint attributes of the next EL.
312 	 */
313 	scr_el3 = read_scr();
314 	scr_el3 &= ~(SCR_NS_BIT | SCR_RW_BIT | SCR_EA_BIT | SCR_FIQ_BIT | SCR_IRQ_BIT |
315 			SCR_ST_BIT | SCR_HCE_BIT | SCR_NSE_BIT);
316 
317 	/*
318 	 * SCR_EL3.RW: Set the execution state, AArch32 or AArch64, for next
319 	 *  Exception level as specified by SPSR.
320 	 */
321 	if (GET_RW(ep->spsr) == MODE_RW_64) {
322 		scr_el3 |= SCR_RW_BIT;
323 	}
324 
325 	/*
326 	 * SCR_EL3.ST: Traps Secure EL1 accesses to the Counter-timer Physical
327 	 * Secure timer registers to EL3, from AArch64 state only, if specified
328 	 * by the entrypoint attributes. If SEL2 is present and enabled, the ST
329 	 * bit always behaves as 1 (i.e. secure physical timer register access
330 	 * is not trapped)
331 	 */
332 	if (EP_GET_ST(ep->h.attr) != 0U) {
333 		scr_el3 |= SCR_ST_BIT;
334 	}
335 
336 	/*
337 	 * If FEAT_HCX is enabled, enable access to HCRX_EL2 by setting
338 	 * SCR_EL3.HXEn.
339 	 */
340 	if (is_feat_hcx_supported()) {
341 		scr_el3 |= SCR_HXEn_BIT;
342 	}
343 
344 	/*
345 	 * If FEAT_RNG_TRAP is enabled, all reads of the RNDR and RNDRRS
346 	 * registers are trapped to EL3.
347 	 */
348 #if ENABLE_FEAT_RNG_TRAP
349 	scr_el3 |= SCR_TRNDR_BIT;
350 #endif
351 
352 #if FAULT_INJECTION_SUPPORT
353 	/* Enable fault injection from lower ELs */
354 	scr_el3 |= SCR_FIEN_BIT;
355 #endif
356 
357 	/*
358 	 * SCR_EL3.TCR2EN: Enable access to TCR2_ELx for AArch64 if present.
359 	 */
360 	if (is_feat_tcr2_supported() && (GET_RW(ep->spsr) == MODE_RW_64)) {
361 		scr_el3 |= SCR_TCR2EN_BIT;
362 	}
363 
364 	/*
365 	 * SCR_EL3.PIEN: Enable permission indirection and overlay
366 	 * registers for AArch64 if present.
367 	 */
368 	if (is_feat_sxpie_supported() || is_feat_sxpoe_supported()) {
369 		scr_el3 |= SCR_PIEN_BIT;
370 	}
371 
372 	/*
373 	 * SCR_EL3.GCSEn: Enable GCS registers for AArch64 if present.
374 	 */
375 	if ((is_feat_gcs_supported()) && (GET_RW(ep->spsr) == MODE_RW_64)) {
376 		scr_el3 |= SCR_GCSEn_BIT;
377 	}
378 
379 	/*
380 	 * CPTR_EL3 was initialized out of reset, copy that value to the
381 	 * context register.
382 	 */
383 	write_ctx_reg(get_el3state_ctx(ctx), CTX_CPTR_EL3, read_cptr_el3());
384 
385 	/*
386 	 * SCR_EL3.HCE: Enable HVC instructions if next execution state is
387 	 * AArch64 and next EL is EL2, or if next execution state is AArch32 and
388 	 * next mode is Hyp.
389 	 * SCR_EL3.FGTEn: Enable Fine Grained Virtualization Traps under the
390 	 * same conditions as HVC instructions and when the processor supports
391 	 * ARMv8.6-FGT.
392 	 * SCR_EL3.ECVEn: Enable Enhanced Counter Virtualization (ECV)
393 	 * CNTPOFF_EL2 register under the same conditions as HVC instructions
394 	 * and when the processor supports ECV.
395 	 */
396 	if (((GET_RW(ep->spsr) == MODE_RW_64) && (GET_EL(ep->spsr) == MODE_EL2))
397 	    || ((GET_RW(ep->spsr) != MODE_RW_64)
398 		&& (GET_M32(ep->spsr) == MODE32_hyp))) {
399 		scr_el3 |= SCR_HCE_BIT;
400 
401 		if (is_feat_fgt_supported()) {
402 			scr_el3 |= SCR_FGTEN_BIT;
403 		}
404 
405 		if (is_feat_ecv_supported()) {
406 			scr_el3 |= SCR_ECVEN_BIT;
407 		}
408 	}
409 
410 	/* Enable WFE trap delay in SCR_EL3 if supported and configured */
411 	if (is_feat_twed_supported()) {
412 		/* Set delay in SCR_EL3 */
413 		scr_el3 &= ~(SCR_TWEDEL_MASK << SCR_TWEDEL_SHIFT);
414 		scr_el3 |= ((TWED_DELAY & SCR_TWEDEL_MASK)
415 				<< SCR_TWEDEL_SHIFT);
416 
417 		/* Enable WFE delay */
418 		scr_el3 |= SCR_TWEDEn_BIT;
419 	}
420 
421 	/*
422 	 * Populate EL3 state so that we've the right context
423 	 * before doing ERET
424 	 */
425 	state = get_el3state_ctx(ctx);
426 	write_ctx_reg(state, CTX_SCR_EL3, scr_el3);
427 	write_ctx_reg(state, CTX_ELR_EL3, ep->pc);
428 	write_ctx_reg(state, CTX_SPSR_EL3, ep->spsr);
429 
430 	/*
431 	 * Store the X0-X7 value from the entrypoint into the context
432 	 * Use memcpy as we are in control of the layout of the structures
433 	 */
434 	gp_regs = get_gpregs_ctx(ctx);
435 	memcpy(gp_regs, (void *)&ep->args, sizeof(aapcs64_params_t));
436 }
437 
438 /*******************************************************************************
439  * Context management library initialization routine. This library is used by
440  * runtime services to share pointers to 'cpu_context' structures for secure
441  * non-secure and realm states. Management of the structures and their associated
442  * memory is not done by the context management library e.g. the PSCI service
443  * manages the cpu context used for entry from and exit to the non-secure state.
444  * The Secure payload dispatcher service manages the context(s) corresponding to
445  * the secure state. It also uses this library to get access to the non-secure
446  * state cpu context pointers.
447  * Lastly, this library provides the API to make SP_EL3 point to the cpu context
448  * which will be used for programming an entry into a lower EL. The same context
449  * will be used to save state upon exception entry from that EL.
450  ******************************************************************************/
451 void __init cm_init(void)
452 {
453 	/*
454 	 * The context management library has only global data to initialize, but
455 	 * that will be done when the BSS is zeroed out.
456 	 */
457 }
458 
459 /*******************************************************************************
460  * This is the high-level function used to initialize the cpu_context 'ctx' for
461  * first use. It performs initializations that are common to all security states
462  * and initializations specific to the security state specified in 'ep'
463  ******************************************************************************/
464 void cm_setup_context(cpu_context_t *ctx, const entry_point_info_t *ep)
465 {
466 	unsigned int security_state;
467 
468 	assert(ctx != NULL);
469 
470 	/*
471 	 * Perform initializations that are common
472 	 * to all security states
473 	 */
474 	setup_context_common(ctx, ep);
475 
476 	security_state = GET_SECURITY_STATE(ep->h.attr);
477 
478 	/* Perform security state specific initializations */
479 	switch (security_state) {
480 	case SECURE:
481 		setup_secure_context(ctx, ep);
482 		break;
483 #if ENABLE_RME
484 	case REALM:
485 		setup_realm_context(ctx, ep);
486 		break;
487 #endif
488 	case NON_SECURE:
489 		setup_ns_context(ctx, ep);
490 		break;
491 	default:
492 		ERROR("Invalid security state\n");
493 		panic();
494 		break;
495 	}
496 }
497 
498 /*******************************************************************************
499  * Enable architecture extensions for EL3 execution. This function only updates
500  * registers in-place which are expected to either never change or be
501  * overwritten by el3_exit.
502  ******************************************************************************/
503 #if IMAGE_BL31
504 void cm_manage_extensions_el3(void)
505 {
506 	if (is_feat_spe_supported()) {
507 		spe_init_el3();
508 	}
509 
510 	if (is_feat_amu_supported()) {
511 		amu_init_el3();
512 	}
513 
514 	if (is_feat_sme_supported()) {
515 		sme_init_el3();
516 	}
517 
518 	if (is_feat_mpam_supported()) {
519 		mpam_init_el3();
520 	}
521 
522 	if (is_feat_trbe_supported()) {
523 		trbe_init_el3();
524 	}
525 
526 	if (is_feat_brbe_supported()) {
527 		brbe_init_el3();
528 	}
529 
530 	if (is_feat_trf_supported()) {
531 		trf_init_el3();
532 	}
533 
534 	pmuv3_init_el3();
535 }
536 #endif /* IMAGE_BL31 */
537 
538 /*******************************************************************************
539  * Enable architecture extensions on first entry to Non-secure world.
540  ******************************************************************************/
541 static void manage_extensions_nonsecure(cpu_context_t *ctx)
542 {
543 #if IMAGE_BL31
544 	if (is_feat_amu_supported()) {
545 		amu_enable(ctx);
546 	}
547 
548 	/* Enable SVE and FPU/SIMD */
549 	if (is_feat_sve_supported()) {
550 		sve_enable(ctx);
551 	}
552 
553 	if (is_feat_sme_supported()) {
554 		sme_enable(ctx);
555 	}
556 
557 	if (is_feat_sys_reg_trace_supported()) {
558 		sys_reg_trace_enable(ctx);
559 	}
560 
561 	pmuv3_enable(ctx);
562 #endif /* IMAGE_BL31 */
563 }
564 
565 /* TODO: move to lib/extensions/pauth when it has been ported to FEAT_STATE */
566 static __unused void enable_pauth_el2(void)
567 {
568 	u_register_t hcr_el2 = read_hcr_el2();
569 	/*
570 	 * For Armv8.3 pointer authentication feature, disable traps to EL2 when
571 	 *  accessing key registers or using pointer authentication instructions
572 	 *  from lower ELs.
573 	 */
574 	hcr_el2 |= (HCR_API_BIT | HCR_APK_BIT);
575 
576 	write_hcr_el2(hcr_el2);
577 }
578 
579 /*******************************************************************************
580  * Enable architecture extensions in-place at EL2 on first entry to Non-secure
581  * world when EL2 is empty and unused.
582  ******************************************************************************/
583 static void manage_extensions_nonsecure_el2_unused(void)
584 {
585 #if IMAGE_BL31
586 	if (is_feat_spe_supported()) {
587 		spe_init_el2_unused();
588 	}
589 
590 	if (is_feat_amu_supported()) {
591 		amu_init_el2_unused();
592 	}
593 
594 	if (is_feat_mpam_supported()) {
595 		mpam_init_el2_unused();
596 	}
597 
598 	if (is_feat_trbe_supported()) {
599 		trbe_init_el2_unused();
600 	}
601 
602 	if (is_feat_sys_reg_trace_supported()) {
603 		sys_reg_trace_init_el2_unused();
604 	}
605 
606 	if (is_feat_trf_supported()) {
607 		trf_init_el2_unused();
608 	}
609 
610 	pmuv3_init_el2_unused();
611 
612 	if (is_feat_sve_supported()) {
613 		sve_init_el2_unused();
614 	}
615 
616 	if (is_feat_sme_supported()) {
617 		sme_init_el2_unused();
618 	}
619 
620 #if ENABLE_PAUTH
621 	enable_pauth_el2();
622 #endif /* ENABLE_PAUTH */
623 #endif /* IMAGE_BL31 */
624 }
625 
626 /*******************************************************************************
627  * Enable architecture extensions on first entry to Secure world.
628  ******************************************************************************/
629 static void manage_extensions_secure(cpu_context_t *ctx)
630 {
631 #if IMAGE_BL31
632 	if (is_feat_sve_supported()) {
633 		if (ENABLE_SVE_FOR_SWD) {
634 		/*
635 		 * Enable SVE and FPU in secure context, secure manager must
636 		 * ensure that the SVE and FPU register contexts are properly
637 		 * managed.
638 		 */
639 			sve_enable(ctx);
640 		} else {
641 		/*
642 		 * Disable SVE and FPU in secure context so non-secure world
643 		 * can safely use them.
644 		 */
645 			sve_disable(ctx);
646 		}
647 	}
648 
649 	if (is_feat_sme_supported()) {
650 		if (ENABLE_SME_FOR_SWD) {
651 		/*
652 		 * Enable SME, SVE, FPU/SIMD in secure context, secure manager
653 		 * must ensure SME, SVE, and FPU/SIMD context properly managed.
654 		 */
655 			sme_init_el3();
656 			sme_enable(ctx);
657 		} else {
658 		/*
659 		 * Disable SME, SVE, FPU/SIMD in secure context so non-secure
660 		 * world can safely use the associated registers.
661 		 */
662 			sme_disable(ctx);
663 		}
664 	}
665 #endif /* IMAGE_BL31 */
666 }
667 
668 /*******************************************************************************
669  * The following function initializes the cpu_context for a CPU specified by
670  * its `cpu_idx` for first use, and sets the initial entrypoint state as
671  * specified by the entry_point_info structure.
672  ******************************************************************************/
673 void cm_init_context_by_index(unsigned int cpu_idx,
674 			      const entry_point_info_t *ep)
675 {
676 	cpu_context_t *ctx;
677 	ctx = cm_get_context_by_index(cpu_idx, GET_SECURITY_STATE(ep->h.attr));
678 	cm_setup_context(ctx, ep);
679 }
680 
681 /*******************************************************************************
682  * The following function initializes the cpu_context for the current CPU
683  * for first use, and sets the initial entrypoint state as specified by the
684  * entry_point_info structure.
685  ******************************************************************************/
686 void cm_init_my_context(const entry_point_info_t *ep)
687 {
688 	cpu_context_t *ctx;
689 	ctx = cm_get_context(GET_SECURITY_STATE(ep->h.attr));
690 	cm_setup_context(ctx, ep);
691 }
692 
693 /* EL2 present but unused, need to disable safely. SCTLR_EL2 can be ignored */
694 static __unused void init_nonsecure_el2_unused(cpu_context_t *ctx)
695 {
696 	u_register_t hcr_el2 = HCR_RESET_VAL;
697 	u_register_t mdcr_el2;
698 	u_register_t scr_el3;
699 
700 	scr_el3 = read_ctx_reg(get_el3state_ctx(ctx), CTX_SCR_EL3);
701 
702 	/* Set EL2 register width: Set HCR_EL2.RW to match SCR_EL3.RW */
703 	if ((scr_el3 & SCR_RW_BIT) != 0U) {
704 		hcr_el2 |= HCR_RW_BIT;
705 	}
706 
707 	write_hcr_el2(hcr_el2);
708 
709 	/*
710 	 * Initialise CPTR_EL2 setting all fields rather than relying on the hw.
711 	 * All fields have architecturally UNKNOWN reset values.
712 	 */
713 	write_cptr_el2(CPTR_EL2_RESET_VAL);
714 
715 	/*
716 	 * Initialise CNTHCTL_EL2. All fields are architecturally UNKNOWN on
717 	 * reset and are set to zero except for field(s) listed below.
718 	 *
719 	 * CNTHCTL_EL2.EL1PTEN: Set to one to disable traps to Hyp mode of
720 	 * Non-secure EL0 and EL1 accesses to the physical timer registers.
721 	 *
722 	 * CNTHCTL_EL2.EL1PCTEN: Set to one to disable traps to Hyp mode of
723 	 * Non-secure EL0 and EL1 accesses to the physical counter registers.
724 	 */
725 	write_cnthctl_el2(CNTHCTL_RESET_VAL | EL1PCEN_BIT | EL1PCTEN_BIT);
726 
727 	/*
728 	 * Initialise CNTVOFF_EL2 to zero as it resets to an architecturally
729 	 * UNKNOWN value.
730 	 */
731 	write_cntvoff_el2(0);
732 
733 	/*
734 	 * Set VPIDR_EL2 and VMPIDR_EL2 to match MIDR_EL1 and MPIDR_EL1
735 	 * respectively.
736 	 */
737 	write_vpidr_el2(read_midr_el1());
738 	write_vmpidr_el2(read_mpidr_el1());
739 
740 	/*
741 	 * Initialise VTTBR_EL2. All fields are architecturally UNKNOWN on reset.
742 	 *
743 	 * VTTBR_EL2.VMID: Set to zero. Even though EL1&0 stage 2 address
744 	 * translation is disabled, cache maintenance operations depend on the
745 	 * VMID.
746 	 *
747 	 * VTTBR_EL2.BADDR: Set to zero as EL1&0 stage 2 address translation is
748 	 * disabled.
749 	 */
750 	write_vttbr_el2(VTTBR_RESET_VAL &
751 		     ~((VTTBR_VMID_MASK << VTTBR_VMID_SHIFT) |
752 		       (VTTBR_BADDR_MASK << VTTBR_BADDR_SHIFT)));
753 
754 	/*
755 	 * Initialise MDCR_EL2, setting all fields rather than relying on hw.
756 	 * Some fields are architecturally UNKNOWN on reset.
757 	 *
758 	 * MDCR_EL2.TDRA: Set to zero so that Non-secure EL0 and EL1 System
759 	 * register accesses to the Debug ROM registers are not trapped to EL2.
760 	 *
761 	 * MDCR_EL2.TDOSA: Set to zero so that Non-secure EL1 System register
762 	 * accesses to the powerdown debug registers are not trapped to EL2.
763 	 *
764 	 * MDCR_EL2.TDA: Set to zero so that System register accesses to the
765 	 * debug registers do not trap to EL2.
766 	 *
767 	 * MDCR_EL2.TDE: Set to zero so that debug exceptions are not routed to
768 	 * EL2.
769 	 */
770 	mdcr_el2 = MDCR_EL2_RESET_VAL &
771 		 ~(MDCR_EL2_TDRA_BIT | MDCR_EL2_TDOSA_BIT | MDCR_EL2_TDA_BIT |
772 		   MDCR_EL2_TDE_BIT);
773 
774 	write_mdcr_el2(mdcr_el2);
775 
776 	/*
777 	 * Initialise HSTR_EL2. All fields are architecturally UNKNOWN on reset.
778 	 *
779 	 * HSTR_EL2.T<n>: Set all these fields to zero so that Non-secure EL0 or
780 	 * EL1 accesses to System registers do not trap to EL2.
781 	 */
782 	write_hstr_el2(HSTR_EL2_RESET_VAL & ~(HSTR_EL2_T_MASK));
783 
784 	/*
785 	 * Initialise CNTHP_CTL_EL2. All fields are architecturally UNKNOWN on
786 	 * reset.
787 	 *
788 	 * CNTHP_CTL_EL2:ENABLE: Set to zero to disable the EL2 physical timer
789 	 * and prevent timer interrupts.
790 	 */
791 	write_cnthp_ctl_el2(CNTHP_CTL_RESET_VAL & ~(CNTHP_CTL_ENABLE_BIT));
792 
793 	manage_extensions_nonsecure_el2_unused();
794 }
795 
796 /*******************************************************************************
797  * Prepare the CPU system registers for first entry into realm, secure, or
798  * normal world.
799  *
800  * If execution is requested to EL2 or hyp mode, SCTLR_EL2 is initialized
801  * If execution is requested to non-secure EL1 or svc mode, and the CPU supports
802  * EL2 then EL2 is disabled by configuring all necessary EL2 registers.
803  * For all entries, the EL1 registers are initialized from the cpu_context
804  ******************************************************************************/
805 void cm_prepare_el3_exit(uint32_t security_state)
806 {
807 	u_register_t sctlr_elx, scr_el3;
808 	cpu_context_t *ctx = cm_get_context(security_state);
809 
810 	assert(ctx != NULL);
811 
812 	if (security_state == NON_SECURE) {
813 		uint64_t el2_implemented = el_implemented(2);
814 
815 		scr_el3 = read_ctx_reg(get_el3state_ctx(ctx),
816 						 CTX_SCR_EL3);
817 
818 		if (((scr_el3 & SCR_HCE_BIT) != 0U)
819 			|| (el2_implemented != EL_IMPL_NONE)) {
820 			/*
821 			 * If context is not being used for EL2, initialize
822 			 * HCRX_EL2 with its init value here.
823 			 */
824 			if (is_feat_hcx_supported()) {
825 				write_hcrx_el2(HCRX_EL2_INIT_VAL);
826 			}
827 		}
828 
829 		if ((scr_el3 & SCR_HCE_BIT) != 0U) {
830 			/* Use SCTLR_EL1.EE value to initialise sctlr_el2 */
831 			sctlr_elx = read_ctx_reg(get_el1_sysregs_ctx(ctx),
832 							   CTX_SCTLR_EL1);
833 			sctlr_elx &= SCTLR_EE_BIT;
834 			sctlr_elx |= SCTLR_EL2_RES1;
835 #if ERRATA_A75_764081
836 			/*
837 			 * If workaround of errata 764081 for Cortex-A75 is used
838 			 * then set SCTLR_EL2.IESB to enable Implicit Error
839 			 * Synchronization Barrier.
840 			 */
841 			sctlr_elx |= SCTLR_IESB_BIT;
842 #endif
843 			write_sctlr_el2(sctlr_elx);
844 		} else if (el2_implemented != EL_IMPL_NONE) {
845 			init_nonsecure_el2_unused(ctx);
846 		}
847 	}
848 
849 	cm_el1_sysregs_context_restore(security_state);
850 	cm_set_next_eret_context(security_state);
851 }
852 
853 #if CTX_INCLUDE_EL2_REGS
854 
855 static void el2_sysregs_context_save_fgt(el2_sysregs_t *ctx)
856 {
857 	write_ctx_reg(ctx, CTX_HDFGRTR_EL2, read_hdfgrtr_el2());
858 	if (is_feat_amu_supported()) {
859 		write_ctx_reg(ctx, CTX_HAFGRTR_EL2, read_hafgrtr_el2());
860 	}
861 	write_ctx_reg(ctx, CTX_HDFGWTR_EL2, read_hdfgwtr_el2());
862 	write_ctx_reg(ctx, CTX_HFGITR_EL2, read_hfgitr_el2());
863 	write_ctx_reg(ctx, CTX_HFGRTR_EL2, read_hfgrtr_el2());
864 	write_ctx_reg(ctx, CTX_HFGWTR_EL2, read_hfgwtr_el2());
865 }
866 
867 static void el2_sysregs_context_restore_fgt(el2_sysregs_t *ctx)
868 {
869 	write_hdfgrtr_el2(read_ctx_reg(ctx, CTX_HDFGRTR_EL2));
870 	if (is_feat_amu_supported()) {
871 		write_hafgrtr_el2(read_ctx_reg(ctx, CTX_HAFGRTR_EL2));
872 	}
873 	write_hdfgwtr_el2(read_ctx_reg(ctx, CTX_HDFGWTR_EL2));
874 	write_hfgitr_el2(read_ctx_reg(ctx, CTX_HFGITR_EL2));
875 	write_hfgrtr_el2(read_ctx_reg(ctx, CTX_HFGRTR_EL2));
876 	write_hfgwtr_el2(read_ctx_reg(ctx, CTX_HFGWTR_EL2));
877 }
878 
879 static void el2_sysregs_context_save_mpam(el2_sysregs_t *ctx)
880 {
881 	u_register_t mpam_idr = read_mpamidr_el1();
882 
883 	write_ctx_reg(ctx, CTX_MPAM2_EL2, read_mpam2_el2());
884 
885 	/*
886 	 * The context registers that we intend to save would be part of the
887 	 * PE's system register frame only if MPAMIDR_EL1.HAS_HCR == 1.
888 	 */
889 	if ((mpam_idr & MPAMIDR_HAS_HCR_BIT) == 0U) {
890 		return;
891 	}
892 
893 	/*
894 	 * MPAMHCR_EL2, MPAMVPMV_EL2 and MPAMVPM0_EL2 are always present if
895 	 * MPAMIDR_HAS_HCR_BIT == 1.
896 	 */
897 	write_ctx_reg(ctx, CTX_MPAMHCR_EL2, read_mpamhcr_el2());
898 	write_ctx_reg(ctx, CTX_MPAMVPM0_EL2, read_mpamvpm0_el2());
899 	write_ctx_reg(ctx, CTX_MPAMVPMV_EL2, read_mpamvpmv_el2());
900 
901 	/*
902 	 * The number of MPAMVPM registers is implementation defined, their
903 	 * number is stored in the MPAMIDR_EL1 register.
904 	 */
905 	switch ((mpam_idr >> MPAMIDR_EL1_VPMR_MAX_SHIFT) & MPAMIDR_EL1_VPMR_MAX_MASK) {
906 	case 7:
907 		write_ctx_reg(ctx, CTX_MPAMVPM7_EL2, read_mpamvpm7_el2());
908 		__fallthrough;
909 	case 6:
910 		write_ctx_reg(ctx, CTX_MPAMVPM6_EL2, read_mpamvpm6_el2());
911 		__fallthrough;
912 	case 5:
913 		write_ctx_reg(ctx, CTX_MPAMVPM5_EL2, read_mpamvpm5_el2());
914 		__fallthrough;
915 	case 4:
916 		write_ctx_reg(ctx, CTX_MPAMVPM4_EL2, read_mpamvpm4_el2());
917 		__fallthrough;
918 	case 3:
919 		write_ctx_reg(ctx, CTX_MPAMVPM3_EL2, read_mpamvpm3_el2());
920 		__fallthrough;
921 	case 2:
922 		write_ctx_reg(ctx, CTX_MPAMVPM2_EL2, read_mpamvpm2_el2());
923 		__fallthrough;
924 	case 1:
925 		write_ctx_reg(ctx, CTX_MPAMVPM1_EL2, read_mpamvpm1_el2());
926 		break;
927 	}
928 }
929 
930 static void el2_sysregs_context_restore_mpam(el2_sysregs_t *ctx)
931 {
932 	u_register_t mpam_idr = read_mpamidr_el1();
933 
934 	write_mpam2_el2(read_ctx_reg(ctx, CTX_MPAM2_EL2));
935 
936 	if ((mpam_idr & MPAMIDR_HAS_HCR_BIT) == 0U) {
937 		return;
938 	}
939 
940 	write_mpamhcr_el2(read_ctx_reg(ctx, CTX_MPAMHCR_EL2));
941 	write_mpamvpm0_el2(read_ctx_reg(ctx, CTX_MPAMVPM0_EL2));
942 	write_mpamvpmv_el2(read_ctx_reg(ctx, CTX_MPAMVPMV_EL2));
943 
944 	switch ((mpam_idr >> MPAMIDR_EL1_VPMR_MAX_SHIFT) & MPAMIDR_EL1_VPMR_MAX_MASK) {
945 	case 7:
946 		write_mpamvpm7_el2(read_ctx_reg(ctx, CTX_MPAMVPM7_EL2));
947 		__fallthrough;
948 	case 6:
949 		write_mpamvpm6_el2(read_ctx_reg(ctx, CTX_MPAMVPM6_EL2));
950 		__fallthrough;
951 	case 5:
952 		write_mpamvpm5_el2(read_ctx_reg(ctx, CTX_MPAMVPM5_EL2));
953 		__fallthrough;
954 	case 4:
955 		write_mpamvpm4_el2(read_ctx_reg(ctx, CTX_MPAMVPM4_EL2));
956 		__fallthrough;
957 	case 3:
958 		write_mpamvpm3_el2(read_ctx_reg(ctx, CTX_MPAMVPM3_EL2));
959 		__fallthrough;
960 	case 2:
961 		write_mpamvpm2_el2(read_ctx_reg(ctx, CTX_MPAMVPM2_EL2));
962 		__fallthrough;
963 	case 1:
964 		write_mpamvpm1_el2(read_ctx_reg(ctx, CTX_MPAMVPM1_EL2));
965 		break;
966 	}
967 }
968 
969 /*******************************************************************************
970  * Save EL2 sysreg context
971  ******************************************************************************/
972 void cm_el2_sysregs_context_save(uint32_t security_state)
973 {
974 	u_register_t scr_el3 = read_scr();
975 
976 	/*
977 	 * Always save the non-secure and realm EL2 context, only save the
978 	 * S-EL2 context if S-EL2 is enabled.
979 	 */
980 	if ((security_state != SECURE) ||
981 	    ((security_state == SECURE) && ((scr_el3 & SCR_EEL2_BIT) != 0U))) {
982 		cpu_context_t *ctx;
983 		el2_sysregs_t *el2_sysregs_ctx;
984 
985 		ctx = cm_get_context(security_state);
986 		assert(ctx != NULL);
987 
988 		el2_sysregs_ctx = get_el2_sysregs_ctx(ctx);
989 
990 		el2_sysregs_context_save_common(el2_sysregs_ctx);
991 #if CTX_INCLUDE_MTE_REGS
992 		el2_sysregs_context_save_mte(el2_sysregs_ctx);
993 #endif
994 		if (is_feat_mpam_supported()) {
995 			el2_sysregs_context_save_mpam(el2_sysregs_ctx);
996 		}
997 
998 		if (is_feat_fgt_supported()) {
999 			el2_sysregs_context_save_fgt(el2_sysregs_ctx);
1000 		}
1001 
1002 		if (is_feat_ecv_v2_supported()) {
1003 			write_ctx_reg(el2_sysregs_ctx, CTX_CNTPOFF_EL2,
1004 				      read_cntpoff_el2());
1005 		}
1006 
1007 		if (is_feat_vhe_supported()) {
1008 			write_ctx_reg(el2_sysregs_ctx, CTX_CONTEXTIDR_EL2,
1009 				      read_contextidr_el2());
1010 			write_ctx_reg(el2_sysregs_ctx, CTX_TTBR1_EL2,
1011 				      read_ttbr1_el2());
1012 		}
1013 
1014 		if (is_feat_ras_supported()) {
1015 			write_ctx_reg(el2_sysregs_ctx, CTX_VDISR_EL2,
1016 				      read_vdisr_el2());
1017 			write_ctx_reg(el2_sysregs_ctx, CTX_VSESR_EL2,
1018 				      read_vsesr_el2());
1019 		}
1020 
1021 		if (is_feat_nv2_supported()) {
1022 			write_ctx_reg(el2_sysregs_ctx, CTX_VNCR_EL2,
1023 				      read_vncr_el2());
1024 		}
1025 
1026 		if (is_feat_trf_supported()) {
1027 			write_ctx_reg(el2_sysregs_ctx, CTX_TRFCR_EL2, read_trfcr_el2());
1028 		}
1029 
1030 		if (is_feat_csv2_2_supported()) {
1031 			write_ctx_reg(el2_sysregs_ctx, CTX_SCXTNUM_EL2,
1032 				      read_scxtnum_el2());
1033 		}
1034 
1035 		if (is_feat_hcx_supported()) {
1036 			write_ctx_reg(el2_sysregs_ctx, CTX_HCRX_EL2, read_hcrx_el2());
1037 		}
1038 		if (is_feat_tcr2_supported()) {
1039 			write_ctx_reg(el2_sysregs_ctx, CTX_TCR2_EL2, read_tcr2_el2());
1040 		}
1041 		if (is_feat_sxpie_supported()) {
1042 			write_ctx_reg(el2_sysregs_ctx, CTX_PIRE0_EL2, read_pire0_el2());
1043 			write_ctx_reg(el2_sysregs_ctx, CTX_PIR_EL2, read_pir_el2());
1044 		}
1045 		if (is_feat_s2pie_supported()) {
1046 			write_ctx_reg(el2_sysregs_ctx, CTX_S2PIR_EL2, read_s2pir_el2());
1047 		}
1048 		if (is_feat_sxpoe_supported()) {
1049 			write_ctx_reg(el2_sysregs_ctx, CTX_POR_EL2, read_por_el2());
1050 		}
1051 		if (is_feat_gcs_supported()) {
1052 			write_ctx_reg(el2_sysregs_ctx, CTX_GCSPR_EL2, read_gcspr_el2());
1053 			write_ctx_reg(el2_sysregs_ctx, CTX_GCSCR_EL2, read_gcscr_el2());
1054 		}
1055 	}
1056 }
1057 
1058 /*******************************************************************************
1059  * Restore EL2 sysreg context
1060  ******************************************************************************/
1061 void cm_el2_sysregs_context_restore(uint32_t security_state)
1062 {
1063 	u_register_t scr_el3 = read_scr();
1064 
1065 	/*
1066 	 * Always restore the non-secure and realm EL2 context, only restore the
1067 	 * S-EL2 context if S-EL2 is enabled.
1068 	 */
1069 	if ((security_state != SECURE) ||
1070 	    ((security_state == SECURE) && ((scr_el3 & SCR_EEL2_BIT) != 0U))) {
1071 		cpu_context_t *ctx;
1072 		el2_sysregs_t *el2_sysregs_ctx;
1073 
1074 		ctx = cm_get_context(security_state);
1075 		assert(ctx != NULL);
1076 
1077 		el2_sysregs_ctx = get_el2_sysregs_ctx(ctx);
1078 
1079 		el2_sysregs_context_restore_common(el2_sysregs_ctx);
1080 #if CTX_INCLUDE_MTE_REGS
1081 		el2_sysregs_context_restore_mte(el2_sysregs_ctx);
1082 #endif
1083 		if (is_feat_mpam_supported()) {
1084 			el2_sysregs_context_restore_mpam(el2_sysregs_ctx);
1085 		}
1086 
1087 		if (is_feat_fgt_supported()) {
1088 			el2_sysregs_context_restore_fgt(el2_sysregs_ctx);
1089 		}
1090 
1091 		if (is_feat_ecv_v2_supported()) {
1092 			write_cntpoff_el2(read_ctx_reg(el2_sysregs_ctx,
1093 						       CTX_CNTPOFF_EL2));
1094 		}
1095 
1096 		if (is_feat_vhe_supported()) {
1097 			write_contextidr_el2(read_ctx_reg(el2_sysregs_ctx, CTX_CONTEXTIDR_EL2));
1098 			write_ttbr1_el2(read_ctx_reg(el2_sysregs_ctx, CTX_TTBR1_EL2));
1099 		}
1100 
1101 		if (is_feat_ras_supported()) {
1102 			write_vdisr_el2(read_ctx_reg(el2_sysregs_ctx, CTX_VDISR_EL2));
1103 			write_vsesr_el2(read_ctx_reg(el2_sysregs_ctx, CTX_VSESR_EL2));
1104 		}
1105 
1106 		if (is_feat_nv2_supported()) {
1107 			write_vncr_el2(read_ctx_reg(el2_sysregs_ctx, CTX_VNCR_EL2));
1108 		}
1109 		if (is_feat_trf_supported()) {
1110 			write_trfcr_el2(read_ctx_reg(el2_sysregs_ctx, CTX_TRFCR_EL2));
1111 		}
1112 
1113 		if (is_feat_csv2_2_supported()) {
1114 			write_scxtnum_el2(read_ctx_reg(el2_sysregs_ctx,
1115 						       CTX_SCXTNUM_EL2));
1116 		}
1117 
1118 		if (is_feat_hcx_supported()) {
1119 			write_hcrx_el2(read_ctx_reg(el2_sysregs_ctx, CTX_HCRX_EL2));
1120 		}
1121 		if (is_feat_tcr2_supported()) {
1122 			write_tcr2_el2(read_ctx_reg(el2_sysregs_ctx, CTX_TCR2_EL2));
1123 		}
1124 		if (is_feat_sxpie_supported()) {
1125 			write_pire0_el2(read_ctx_reg(el2_sysregs_ctx, CTX_PIRE0_EL2));
1126 			write_pir_el2(read_ctx_reg(el2_sysregs_ctx, CTX_PIR_EL2));
1127 		}
1128 		if (is_feat_s2pie_supported()) {
1129 			write_s2pir_el2(read_ctx_reg(el2_sysregs_ctx, CTX_S2PIR_EL2));
1130 		}
1131 		if (is_feat_sxpoe_supported()) {
1132 			write_por_el2(read_ctx_reg(el2_sysregs_ctx, CTX_POR_EL2));
1133 		}
1134 		if (is_feat_gcs_supported()) {
1135 			write_gcscr_el2(read_ctx_reg(el2_sysregs_ctx, CTX_GCSCR_EL2));
1136 			write_gcspr_el2(read_ctx_reg(el2_sysregs_ctx, CTX_GCSPR_EL2));
1137 		}
1138 	}
1139 }
1140 #endif /* CTX_INCLUDE_EL2_REGS */
1141 
1142 /*******************************************************************************
1143  * This function is used to exit to Non-secure world. If CTX_INCLUDE_EL2_REGS
1144  * is enabled, it restores EL1 and EL2 sysreg contexts instead of directly
1145  * updating EL1 and EL2 registers. Otherwise, it calls the generic
1146  * cm_prepare_el3_exit function.
1147  ******************************************************************************/
1148 void cm_prepare_el3_exit_ns(void)
1149 {
1150 #if CTX_INCLUDE_EL2_REGS
1151 #if ENABLE_ASSERTIONS
1152 	cpu_context_t *ctx = cm_get_context(NON_SECURE);
1153 	assert(ctx != NULL);
1154 
1155 	/* Assert that EL2 is used. */
1156 	u_register_t scr_el3 = read_ctx_reg(get_el3state_ctx(ctx), CTX_SCR_EL3);
1157 	assert(((scr_el3 & SCR_HCE_BIT) != 0UL) &&
1158 			(el_implemented(2U) != EL_IMPL_NONE));
1159 #endif /* ENABLE_ASSERTIONS */
1160 
1161 	/*
1162 	 * Set the NS bit to be able to access the ICC_SRE_EL2
1163 	 * register when restoring context.
1164 	 */
1165 	write_scr_el3(read_scr_el3() | SCR_NS_BIT);
1166 
1167 	/*
1168 	 * Ensure the NS bit change is committed before the EL2/EL1
1169 	 * state restoration.
1170 	 */
1171 	isb();
1172 
1173 	/* Restore EL2 and EL1 sysreg contexts */
1174 	cm_el2_sysregs_context_restore(NON_SECURE);
1175 	cm_el1_sysregs_context_restore(NON_SECURE);
1176 	cm_set_next_eret_context(NON_SECURE);
1177 #else
1178 	cm_prepare_el3_exit(NON_SECURE);
1179 #endif /* CTX_INCLUDE_EL2_REGS */
1180 }
1181 
1182 /*******************************************************************************
1183  * The next four functions are used by runtime services to save and restore
1184  * EL1 context on the 'cpu_context' structure for the specified security
1185  * state.
1186  ******************************************************************************/
1187 void cm_el1_sysregs_context_save(uint32_t security_state)
1188 {
1189 	cpu_context_t *ctx;
1190 
1191 	ctx = cm_get_context(security_state);
1192 	assert(ctx != NULL);
1193 
1194 	el1_sysregs_context_save(get_el1_sysregs_ctx(ctx));
1195 
1196 #if IMAGE_BL31
1197 	if (security_state == SECURE)
1198 		PUBLISH_EVENT(cm_exited_secure_world);
1199 	else
1200 		PUBLISH_EVENT(cm_exited_normal_world);
1201 #endif
1202 }
1203 
1204 void cm_el1_sysregs_context_restore(uint32_t security_state)
1205 {
1206 	cpu_context_t *ctx;
1207 
1208 	ctx = cm_get_context(security_state);
1209 	assert(ctx != NULL);
1210 
1211 	el1_sysregs_context_restore(get_el1_sysregs_ctx(ctx));
1212 
1213 #if IMAGE_BL31
1214 	if (security_state == SECURE)
1215 		PUBLISH_EVENT(cm_entering_secure_world);
1216 	else
1217 		PUBLISH_EVENT(cm_entering_normal_world);
1218 #endif
1219 }
1220 
1221 /*******************************************************************************
1222  * This function populates ELR_EL3 member of 'cpu_context' pertaining to the
1223  * given security state with the given entrypoint
1224  ******************************************************************************/
1225 void cm_set_elr_el3(uint32_t security_state, uintptr_t entrypoint)
1226 {
1227 	cpu_context_t *ctx;
1228 	el3_state_t *state;
1229 
1230 	ctx = cm_get_context(security_state);
1231 	assert(ctx != NULL);
1232 
1233 	/* Populate EL3 state so that ERET jumps to the correct entry */
1234 	state = get_el3state_ctx(ctx);
1235 	write_ctx_reg(state, CTX_ELR_EL3, entrypoint);
1236 }
1237 
1238 /*******************************************************************************
1239  * This function populates ELR_EL3 and SPSR_EL3 members of 'cpu_context'
1240  * pertaining to the given security state
1241  ******************************************************************************/
1242 void cm_set_elr_spsr_el3(uint32_t security_state,
1243 			uintptr_t entrypoint, uint32_t spsr)
1244 {
1245 	cpu_context_t *ctx;
1246 	el3_state_t *state;
1247 
1248 	ctx = cm_get_context(security_state);
1249 	assert(ctx != NULL);
1250 
1251 	/* Populate EL3 state so that ERET jumps to the correct entry */
1252 	state = get_el3state_ctx(ctx);
1253 	write_ctx_reg(state, CTX_ELR_EL3, entrypoint);
1254 	write_ctx_reg(state, CTX_SPSR_EL3, spsr);
1255 }
1256 
1257 /*******************************************************************************
1258  * This function updates a single bit in the SCR_EL3 member of the 'cpu_context'
1259  * pertaining to the given security state using the value and bit position
1260  * specified in the parameters. It preserves all other bits.
1261  ******************************************************************************/
1262 void cm_write_scr_el3_bit(uint32_t security_state,
1263 			  uint32_t bit_pos,
1264 			  uint32_t value)
1265 {
1266 	cpu_context_t *ctx;
1267 	el3_state_t *state;
1268 	u_register_t scr_el3;
1269 
1270 	ctx = cm_get_context(security_state);
1271 	assert(ctx != NULL);
1272 
1273 	/* Ensure that the bit position is a valid one */
1274 	assert(((1UL << bit_pos) & SCR_VALID_BIT_MASK) != 0U);
1275 
1276 	/* Ensure that the 'value' is only a bit wide */
1277 	assert(value <= 1U);
1278 
1279 	/*
1280 	 * Get the SCR_EL3 value from the cpu context, clear the desired bit
1281 	 * and set it to its new value.
1282 	 */
1283 	state = get_el3state_ctx(ctx);
1284 	scr_el3 = read_ctx_reg(state, CTX_SCR_EL3);
1285 	scr_el3 &= ~(1UL << bit_pos);
1286 	scr_el3 |= (u_register_t)value << bit_pos;
1287 	write_ctx_reg(state, CTX_SCR_EL3, scr_el3);
1288 }
1289 
1290 /*******************************************************************************
1291  * This function retrieves SCR_EL3 member of 'cpu_context' pertaining to the
1292  * given security state.
1293  ******************************************************************************/
1294 u_register_t cm_get_scr_el3(uint32_t security_state)
1295 {
1296 	cpu_context_t *ctx;
1297 	el3_state_t *state;
1298 
1299 	ctx = cm_get_context(security_state);
1300 	assert(ctx != NULL);
1301 
1302 	/* Populate EL3 state so that ERET jumps to the correct entry */
1303 	state = get_el3state_ctx(ctx);
1304 	return read_ctx_reg(state, CTX_SCR_EL3);
1305 }
1306 
1307 /*******************************************************************************
1308  * This function is used to program the context that's used for exception
1309  * return. This initializes the SP_EL3 to a pointer to a 'cpu_context' set for
1310  * the required security state
1311  ******************************************************************************/
1312 void cm_set_next_eret_context(uint32_t security_state)
1313 {
1314 	cpu_context_t *ctx;
1315 
1316 	ctx = cm_get_context(security_state);
1317 	assert(ctx != NULL);
1318 
1319 	cm_set_next_context(ctx);
1320 }
1321