xref: /rk3399_ARM-atf/lib/el3_runtime/aarch64/context.S (revision 1d6d6802dd547c8b378a9a47572ee72e68cceb3b)
1/*
2 * Copyright (c) 2013-2023, Arm Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7#include <arch.h>
8#include <asm_macros.S>
9#include <assert_macros.S>
10#include <context.h>
11#include <el3_common_macros.S>
12
13#if CTX_INCLUDE_EL2_REGS
14	.global	el2_sysregs_context_save_common
15	.global	el2_sysregs_context_restore_common
16#if CTX_INCLUDE_MTE_REGS
17	.global	el2_sysregs_context_save_mte
18	.global	el2_sysregs_context_restore_mte
19#endif /* CTX_INCLUDE_MTE_REGS */
20#if RAS_EXTENSION
21	.global	el2_sysregs_context_save_ras
22	.global	el2_sysregs_context_restore_ras
23#endif /* RAS_EXTENSION */
24#endif /* CTX_INCLUDE_EL2_REGS */
25
26	.global	el1_sysregs_context_save
27	.global	el1_sysregs_context_restore
28#if CTX_INCLUDE_FPREGS
29	.global	fpregs_context_save
30	.global	fpregs_context_restore
31#endif /* CTX_INCLUDE_FPREGS */
32	.global	prepare_el3_entry
33	.global	restore_gp_pmcr_pauth_regs
34	.global save_and_update_ptw_el1_sys_regs
35	.global	el3_exit
36
37#if CTX_INCLUDE_EL2_REGS
38
39/* -----------------------------------------------------
40 * The following functions strictly follow the AArch64
41 * PCS to use x9-x16 (temporary caller-saved registers)
42 * to save/restore EL2 system register context.
43 * el2_sysregs_context_save/restore_common functions
44 * save and restore registers that are common to all
45 * configurations. The rest of the functions save and
46 * restore EL2 system registers that are present when a
47 * particular feature is enabled. All functions assume
48 * that 'x0' is pointing to a 'el2_sys_regs' structure
49 * where the register context will be saved/restored.
50 *
51 * The following registers are not added.
52 * AMEVCNTVOFF0<n>_EL2
53 * AMEVCNTVOFF1<n>_EL2
54 * ICH_AP0R<n>_EL2
55 * ICH_AP1R<n>_EL2
56 * ICH_LR<n>_EL2
57 * -----------------------------------------------------
58 */
59func el2_sysregs_context_save_common
60	mrs	x9, actlr_el2
61	mrs	x10, afsr0_el2
62	stp	x9, x10, [x0, #CTX_ACTLR_EL2]
63
64	mrs	x11, afsr1_el2
65	mrs	x12, amair_el2
66	stp	x11, x12, [x0, #CTX_AFSR1_EL2]
67
68	mrs	x13, cnthctl_el2
69	mrs	x14, cntvoff_el2
70	stp	x13, x14, [x0, #CTX_CNTHCTL_EL2]
71
72	mrs	x15, cptr_el2
73	str	x15, [x0, #CTX_CPTR_EL2]
74
75#if CTX_INCLUDE_AARCH32_REGS
76	mrs	x16, dbgvcr32_el2
77	str	x16, [x0, #CTX_DBGVCR32_EL2]
78#endif /* CTX_INCLUDE_AARCH32_REGS */
79
80	mrs	x9, elr_el2
81	mrs	x10, esr_el2
82	stp	x9, x10, [x0, #CTX_ELR_EL2]
83
84	mrs	x11, far_el2
85	mrs	x12, hacr_el2
86	stp	x11, x12, [x0, #CTX_FAR_EL2]
87
88	mrs	x13, hcr_el2
89	mrs	x14, hpfar_el2
90	stp	x13, x14, [x0, #CTX_HCR_EL2]
91
92	mrs	x15, hstr_el2
93	mrs	x16, ICC_SRE_EL2
94	stp	x15, x16, [x0, #CTX_HSTR_EL2]
95
96	mrs	x9, ICH_HCR_EL2
97	mrs	x10, ICH_VMCR_EL2
98	stp	x9, x10, [x0, #CTX_ICH_HCR_EL2]
99
100	mrs	x11, mair_el2
101	mrs	x12, mdcr_el2
102	stp	x11, x12, [x0, #CTX_MAIR_EL2]
103
104	mrs	x14, sctlr_el2
105	str	x14, [x0, #CTX_SCTLR_EL2]
106
107	mrs	x15, spsr_el2
108	mrs	x16, sp_el2
109	stp	x15, x16, [x0, #CTX_SPSR_EL2]
110
111	mrs	x9, tcr_el2
112	mrs	x10, tpidr_el2
113	stp	x9, x10, [x0, #CTX_TCR_EL2]
114
115	mrs	x11, ttbr0_el2
116	mrs	x12, vbar_el2
117	stp	x11, x12, [x0, #CTX_TTBR0_EL2]
118
119	mrs	x13, vmpidr_el2
120	mrs	x14, vpidr_el2
121	stp	x13, x14, [x0, #CTX_VMPIDR_EL2]
122
123	mrs	x15, vtcr_el2
124	mrs	x16, vttbr_el2
125	stp	x15, x16, [x0, #CTX_VTCR_EL2]
126	ret
127endfunc el2_sysregs_context_save_common
128
129func el2_sysregs_context_restore_common
130	ldp	x9, x10, [x0, #CTX_ACTLR_EL2]
131	msr	actlr_el2, x9
132	msr	afsr0_el2, x10
133
134	ldp	x11, x12, [x0, #CTX_AFSR1_EL2]
135	msr	afsr1_el2, x11
136	msr	amair_el2, x12
137
138	ldp	x13, x14, [x0, #CTX_CNTHCTL_EL2]
139	msr	cnthctl_el2, x13
140	msr	cntvoff_el2, x14
141
142	ldr	x15, [x0, #CTX_CPTR_EL2]
143	msr	cptr_el2, x15
144
145#if CTX_INCLUDE_AARCH32_REGS
146	ldr	x16, [x0, #CTX_DBGVCR32_EL2]
147	msr	dbgvcr32_el2, x16
148#endif /* CTX_INCLUDE_AARCH32_REGS */
149
150	ldp	x9, x10, [x0, #CTX_ELR_EL2]
151	msr	elr_el2, x9
152	msr	esr_el2, x10
153
154	ldp	x11, x12, [x0, #CTX_FAR_EL2]
155	msr	far_el2, x11
156	msr	hacr_el2, x12
157
158	ldp	x13, x14, [x0, #CTX_HCR_EL2]
159	msr	hcr_el2, x13
160	msr	hpfar_el2, x14
161
162	ldp	x15, x16, [x0, #CTX_HSTR_EL2]
163	msr	hstr_el2, x15
164	msr	ICC_SRE_EL2, x16
165
166	ldp	x9, x10, [x0, #CTX_ICH_HCR_EL2]
167	msr	ICH_HCR_EL2, x9
168	msr	ICH_VMCR_EL2, x10
169
170	ldp	x11, x12, [x0, #CTX_MAIR_EL2]
171	msr	mair_el2, x11
172	msr	mdcr_el2, x12
173
174	ldr	x14, [x0, #CTX_SCTLR_EL2]
175	msr	sctlr_el2, x14
176
177	ldp	x15, x16, [x0, #CTX_SPSR_EL2]
178	msr	spsr_el2, x15
179	msr	sp_el2, x16
180
181	ldp	x9, x10, [x0, #CTX_TCR_EL2]
182	msr	tcr_el2, x9
183	msr	tpidr_el2, x10
184
185	ldp	x11, x12, [x0, #CTX_TTBR0_EL2]
186	msr	ttbr0_el2, x11
187	msr	vbar_el2, x12
188
189	ldp	x13, x14, [x0, #CTX_VMPIDR_EL2]
190	msr	vmpidr_el2, x13
191	msr	vpidr_el2, x14
192
193	ldp	x15, x16, [x0, #CTX_VTCR_EL2]
194	msr	vtcr_el2, x15
195	msr	vttbr_el2, x16
196	ret
197endfunc el2_sysregs_context_restore_common
198
199#if CTX_INCLUDE_MTE_REGS
200func el2_sysregs_context_save_mte
201	mrs	x9, TFSR_EL2
202	str	x9, [x0, #CTX_TFSR_EL2]
203	ret
204endfunc el2_sysregs_context_save_mte
205
206func el2_sysregs_context_restore_mte
207	ldr	x9, [x0, #CTX_TFSR_EL2]
208	msr	TFSR_EL2, x9
209	ret
210endfunc el2_sysregs_context_restore_mte
211#endif /* CTX_INCLUDE_MTE_REGS */
212
213#if RAS_EXTENSION
214func el2_sysregs_context_save_ras
215	/*
216	 * VDISR_EL2 and VSESR_EL2 registers are saved only when
217	 * FEAT_RAS is supported.
218	 */
219	mrs	x11, vdisr_el2
220	mrs	x12, vsesr_el2
221	stp	x11, x12, [x0, #CTX_VDISR_EL2]
222	ret
223endfunc el2_sysregs_context_save_ras
224
225func el2_sysregs_context_restore_ras
226	/*
227	 * VDISR_EL2 and VSESR_EL2 registers are restored only when FEAT_RAS
228	 * is supported.
229	 */
230	ldp	x11, x12, [x0, #CTX_VDISR_EL2]
231	msr	vdisr_el2, x11
232	msr	vsesr_el2, x12
233	ret
234endfunc el2_sysregs_context_restore_ras
235#endif /* RAS_EXTENSION */
236
237#endif /* CTX_INCLUDE_EL2_REGS */
238
239/* ------------------------------------------------------------------
240 * The following function strictly follows the AArch64 PCS to use
241 * x9-x17 (temporary caller-saved registers) to save EL1 system
242 * register context. It assumes that 'x0' is pointing to a
243 * 'el1_sys_regs' structure where the register context will be saved.
244 * ------------------------------------------------------------------
245 */
246func el1_sysregs_context_save
247
248	mrs	x9, spsr_el1
249	mrs	x10, elr_el1
250	stp	x9, x10, [x0, #CTX_SPSR_EL1]
251
252#if !ERRATA_SPECULATIVE_AT
253	mrs	x15, sctlr_el1
254	mrs	x16, tcr_el1
255	stp	x15, x16, [x0, #CTX_SCTLR_EL1]
256#endif /* ERRATA_SPECULATIVE_AT */
257
258	mrs	x17, cpacr_el1
259	mrs	x9, csselr_el1
260	stp	x17, x9, [x0, #CTX_CPACR_EL1]
261
262	mrs	x10, sp_el1
263	mrs	x11, esr_el1
264	stp	x10, x11, [x0, #CTX_SP_EL1]
265
266	mrs	x12, ttbr0_el1
267	mrs	x13, ttbr1_el1
268	stp	x12, x13, [x0, #CTX_TTBR0_EL1]
269
270	mrs	x14, mair_el1
271	mrs	x15, amair_el1
272	stp	x14, x15, [x0, #CTX_MAIR_EL1]
273
274	mrs	x16, actlr_el1
275	mrs	x17, tpidr_el1
276	stp	x16, x17, [x0, #CTX_ACTLR_EL1]
277
278	mrs	x9, tpidr_el0
279	mrs	x10, tpidrro_el0
280	stp	x9, x10, [x0, #CTX_TPIDR_EL0]
281
282	mrs	x13, par_el1
283	mrs	x14, far_el1
284	stp	x13, x14, [x0, #CTX_PAR_EL1]
285
286	mrs	x15, afsr0_el1
287	mrs	x16, afsr1_el1
288	stp	x15, x16, [x0, #CTX_AFSR0_EL1]
289
290	mrs	x17, contextidr_el1
291	mrs	x9, vbar_el1
292	stp	x17, x9, [x0, #CTX_CONTEXTIDR_EL1]
293
294	/* Save AArch32 system registers if the build has instructed so */
295#if CTX_INCLUDE_AARCH32_REGS
296	mrs	x11, spsr_abt
297	mrs	x12, spsr_und
298	stp	x11, x12, [x0, #CTX_SPSR_ABT]
299
300	mrs	x13, spsr_irq
301	mrs	x14, spsr_fiq
302	stp	x13, x14, [x0, #CTX_SPSR_IRQ]
303
304	mrs	x15, dacr32_el2
305	mrs	x16, ifsr32_el2
306	stp	x15, x16, [x0, #CTX_DACR32_EL2]
307#endif /* CTX_INCLUDE_AARCH32_REGS */
308
309	/* Save NS timer registers if the build has instructed so */
310#if NS_TIMER_SWITCH
311	mrs	x10, cntp_ctl_el0
312	mrs	x11, cntp_cval_el0
313	stp	x10, x11, [x0, #CTX_CNTP_CTL_EL0]
314
315	mrs	x12, cntv_ctl_el0
316	mrs	x13, cntv_cval_el0
317	stp	x12, x13, [x0, #CTX_CNTV_CTL_EL0]
318
319	mrs	x14, cntkctl_el1
320	str	x14, [x0, #CTX_CNTKCTL_EL1]
321#endif /* NS_TIMER_SWITCH */
322
323	/* Save MTE system registers if the build has instructed so */
324#if CTX_INCLUDE_MTE_REGS
325	mrs	x15, TFSRE0_EL1
326	mrs	x16, TFSR_EL1
327	stp	x15, x16, [x0, #CTX_TFSRE0_EL1]
328
329	mrs	x9, RGSR_EL1
330	mrs	x10, GCR_EL1
331	stp	x9, x10, [x0, #CTX_RGSR_EL1]
332#endif /* CTX_INCLUDE_MTE_REGS */
333
334	ret
335endfunc el1_sysregs_context_save
336
337/* ------------------------------------------------------------------
338 * The following function strictly follows the AArch64 PCS to use
339 * x9-x17 (temporary caller-saved registers) to restore EL1 system
340 * register context.  It assumes that 'x0' is pointing to a
341 * 'el1_sys_regs' structure from where the register context will be
342 * restored
343 * ------------------------------------------------------------------
344 */
345func el1_sysregs_context_restore
346
347	ldp	x9, x10, [x0, #CTX_SPSR_EL1]
348	msr	spsr_el1, x9
349	msr	elr_el1, x10
350
351#if !ERRATA_SPECULATIVE_AT
352	ldp	x15, x16, [x0, #CTX_SCTLR_EL1]
353	msr	sctlr_el1, x15
354	msr	tcr_el1, x16
355#endif /* ERRATA_SPECULATIVE_AT */
356
357	ldp	x17, x9, [x0, #CTX_CPACR_EL1]
358	msr	cpacr_el1, x17
359	msr	csselr_el1, x9
360
361	ldp	x10, x11, [x0, #CTX_SP_EL1]
362	msr	sp_el1, x10
363	msr	esr_el1, x11
364
365	ldp	x12, x13, [x0, #CTX_TTBR0_EL1]
366	msr	ttbr0_el1, x12
367	msr	ttbr1_el1, x13
368
369	ldp	x14, x15, [x0, #CTX_MAIR_EL1]
370	msr	mair_el1, x14
371	msr	amair_el1, x15
372
373	ldp 	x16, x17, [x0, #CTX_ACTLR_EL1]
374	msr	actlr_el1, x16
375	msr	tpidr_el1, x17
376
377	ldp	x9, x10, [x0, #CTX_TPIDR_EL0]
378	msr	tpidr_el0, x9
379	msr	tpidrro_el0, x10
380
381	ldp	x13, x14, [x0, #CTX_PAR_EL1]
382	msr	par_el1, x13
383	msr	far_el1, x14
384
385	ldp	x15, x16, [x0, #CTX_AFSR0_EL1]
386	msr	afsr0_el1, x15
387	msr	afsr1_el1, x16
388
389	ldp	x17, x9, [x0, #CTX_CONTEXTIDR_EL1]
390	msr	contextidr_el1, x17
391	msr	vbar_el1, x9
392
393	/* Restore AArch32 system registers if the build has instructed so */
394#if CTX_INCLUDE_AARCH32_REGS
395	ldp	x11, x12, [x0, #CTX_SPSR_ABT]
396	msr	spsr_abt, x11
397	msr	spsr_und, x12
398
399	ldp	x13, x14, [x0, #CTX_SPSR_IRQ]
400	msr	spsr_irq, x13
401	msr	spsr_fiq, x14
402
403	ldp	x15, x16, [x0, #CTX_DACR32_EL2]
404	msr	dacr32_el2, x15
405	msr	ifsr32_el2, x16
406#endif /* CTX_INCLUDE_AARCH32_REGS */
407
408	/* Restore NS timer registers if the build has instructed so */
409#if NS_TIMER_SWITCH
410	ldp	x10, x11, [x0, #CTX_CNTP_CTL_EL0]
411	msr	cntp_ctl_el0, x10
412	msr	cntp_cval_el0, x11
413
414	ldp	x12, x13, [x0, #CTX_CNTV_CTL_EL0]
415	msr	cntv_ctl_el0, x12
416	msr	cntv_cval_el0, x13
417
418	ldr	x14, [x0, #CTX_CNTKCTL_EL1]
419	msr	cntkctl_el1, x14
420#endif /* NS_TIMER_SWITCH */
421
422	/* Restore MTE system registers if the build has instructed so */
423#if CTX_INCLUDE_MTE_REGS
424	ldp	x11, x12, [x0, #CTX_TFSRE0_EL1]
425	msr	TFSRE0_EL1, x11
426	msr	TFSR_EL1, x12
427
428	ldp	x13, x14, [x0, #CTX_RGSR_EL1]
429	msr	RGSR_EL1, x13
430	msr	GCR_EL1, x14
431#endif /* CTX_INCLUDE_MTE_REGS */
432
433	/* No explict ISB required here as ERET covers it */
434	ret
435endfunc el1_sysregs_context_restore
436
437/* ------------------------------------------------------------------
438 * The following function follows the aapcs_64 strictly to use
439 * x9-x17 (temporary caller-saved registers according to AArch64 PCS)
440 * to save floating point register context. It assumes that 'x0' is
441 * pointing to a 'fp_regs' structure where the register context will
442 * be saved.
443 *
444 * Access to VFP registers will trap if CPTR_EL3.TFP is set.
445 * However currently we don't use VFP registers nor set traps in
446 * Trusted Firmware, and assume it's cleared.
447 *
448 * TODO: Revisit when VFP is used in secure world
449 * ------------------------------------------------------------------
450 */
451#if CTX_INCLUDE_FPREGS
452func fpregs_context_save
453	stp	q0, q1, [x0, #CTX_FP_Q0]
454	stp	q2, q3, [x0, #CTX_FP_Q2]
455	stp	q4, q5, [x0, #CTX_FP_Q4]
456	stp	q6, q7, [x0, #CTX_FP_Q6]
457	stp	q8, q9, [x0, #CTX_FP_Q8]
458	stp	q10, q11, [x0, #CTX_FP_Q10]
459	stp	q12, q13, [x0, #CTX_FP_Q12]
460	stp	q14, q15, [x0, #CTX_FP_Q14]
461	stp	q16, q17, [x0, #CTX_FP_Q16]
462	stp	q18, q19, [x0, #CTX_FP_Q18]
463	stp	q20, q21, [x0, #CTX_FP_Q20]
464	stp	q22, q23, [x0, #CTX_FP_Q22]
465	stp	q24, q25, [x0, #CTX_FP_Q24]
466	stp	q26, q27, [x0, #CTX_FP_Q26]
467	stp	q28, q29, [x0, #CTX_FP_Q28]
468	stp	q30, q31, [x0, #CTX_FP_Q30]
469
470	mrs	x9, fpsr
471	str	x9, [x0, #CTX_FP_FPSR]
472
473	mrs	x10, fpcr
474	str	x10, [x0, #CTX_FP_FPCR]
475
476#if CTX_INCLUDE_AARCH32_REGS
477	mrs	x11, fpexc32_el2
478	str	x11, [x0, #CTX_FP_FPEXC32_EL2]
479#endif /* CTX_INCLUDE_AARCH32_REGS */
480	ret
481endfunc fpregs_context_save
482
483/* ------------------------------------------------------------------
484 * The following function follows the aapcs_64 strictly to use x9-x17
485 * (temporary caller-saved registers according to AArch64 PCS) to
486 * restore floating point register context. It assumes that 'x0' is
487 * pointing to a 'fp_regs' structure from where the register context
488 * will be restored.
489 *
490 * Access to VFP registers will trap if CPTR_EL3.TFP is set.
491 * However currently we don't use VFP registers nor set traps in
492 * Trusted Firmware, and assume it's cleared.
493 *
494 * TODO: Revisit when VFP is used in secure world
495 * ------------------------------------------------------------------
496 */
497func fpregs_context_restore
498	ldp	q0, q1, [x0, #CTX_FP_Q0]
499	ldp	q2, q3, [x0, #CTX_FP_Q2]
500	ldp	q4, q5, [x0, #CTX_FP_Q4]
501	ldp	q6, q7, [x0, #CTX_FP_Q6]
502	ldp	q8, q9, [x0, #CTX_FP_Q8]
503	ldp	q10, q11, [x0, #CTX_FP_Q10]
504	ldp	q12, q13, [x0, #CTX_FP_Q12]
505	ldp	q14, q15, [x0, #CTX_FP_Q14]
506	ldp	q16, q17, [x0, #CTX_FP_Q16]
507	ldp	q18, q19, [x0, #CTX_FP_Q18]
508	ldp	q20, q21, [x0, #CTX_FP_Q20]
509	ldp	q22, q23, [x0, #CTX_FP_Q22]
510	ldp	q24, q25, [x0, #CTX_FP_Q24]
511	ldp	q26, q27, [x0, #CTX_FP_Q26]
512	ldp	q28, q29, [x0, #CTX_FP_Q28]
513	ldp	q30, q31, [x0, #CTX_FP_Q30]
514
515	ldr	x9, [x0, #CTX_FP_FPSR]
516	msr	fpsr, x9
517
518	ldr	x10, [x0, #CTX_FP_FPCR]
519	msr	fpcr, x10
520
521#if CTX_INCLUDE_AARCH32_REGS
522	ldr	x11, [x0, #CTX_FP_FPEXC32_EL2]
523	msr	fpexc32_el2, x11
524#endif /* CTX_INCLUDE_AARCH32_REGS */
525
526	/*
527	 * No explict ISB required here as ERET to
528	 * switch to secure EL1 or non-secure world
529	 * covers it
530	 */
531
532	ret
533endfunc fpregs_context_restore
534#endif /* CTX_INCLUDE_FPREGS */
535
536	/*
537	 * Set SCR_EL3.EA bit to enable SErrors at EL3
538	 */
539	.macro enable_serror_at_el3
540	mrs     x8, scr_el3
541	orr     x8, x8, #SCR_EA_BIT
542	msr     scr_el3, x8
543	.endm
544
545	/*
546	 * Set the PSTATE bits not set when the exception was taken as
547	 * described in the AArch64.TakeException() pseudocode function
548	 * in ARM DDI 0487F.c page J1-7635 to a default value.
549	 */
550	.macro set_unset_pstate_bits
551	/*
552	 * If Data Independent Timing (DIT) functionality is implemented,
553	 * always enable DIT in EL3
554	 */
555#if ENABLE_FEAT_DIT
556#if ENABLE_FEAT_DIT == 2
557	mrs	x8, id_aa64pfr0_el1
558	and	x8, x8, #(ID_AA64PFR0_DIT_MASK << ID_AA64PFR0_DIT_SHIFT)
559	cbz	x8, 1f
560#endif
561	mov     x8, #DIT_BIT
562	msr     DIT, x8
5631:
564#endif /* ENABLE_FEAT_DIT */
565	.endm /* set_unset_pstate_bits */
566
567/* ------------------------------------------------------------------
568 * The following macro is used to save and restore all the general
569 * purpose and ARMv8.3-PAuth (if enabled) registers.
570 * It also checks if the Secure Cycle Counter (PMCCNTR_EL0)
571 * is disabled in EL3/Secure (ARMv8.5-PMU), wherein PMCCNTR_EL0
572 * needs not to be saved/restored during world switch.
573 *
574 * Ideally we would only save and restore the callee saved registers
575 * when a world switch occurs but that type of implementation is more
576 * complex. So currently we will always save and restore these
577 * registers on entry and exit of EL3.
578 * clobbers: x18
579 * ------------------------------------------------------------------
580 */
581	.macro save_gp_pmcr_pauth_regs
582	stp	x0, x1, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X0]
583	stp	x2, x3, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X2]
584	stp	x4, x5, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X4]
585	stp	x6, x7, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X6]
586	stp	x8, x9, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X8]
587	stp	x10, x11, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X10]
588	stp	x12, x13, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X12]
589	stp	x14, x15, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X14]
590	stp	x16, x17, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X16]
591	stp	x18, x19, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X18]
592	stp	x20, x21, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X20]
593	stp	x22, x23, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X22]
594	stp	x24, x25, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X24]
595	stp	x26, x27, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X26]
596	stp	x28, x29, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X28]
597	mrs	x18, sp_el0
598	str	x18, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_SP_EL0]
599	mrs	x9, pmcr_el0
600	str	x9, [sp, #CTX_EL3STATE_OFFSET + CTX_PMCR_EL0]
601	/* Disable cycle counter when event counting is prohibited */
602	orr	x9, x9, #PMCR_EL0_DP_BIT
603	msr	pmcr_el0, x9
604	isb
605#if CTX_INCLUDE_PAUTH_REGS
606	/* ----------------------------------------------------------
607 	 * Save the ARMv8.3-PAuth keys as they are not banked
608 	 * by exception level
609	 * ----------------------------------------------------------
610	 */
611	add	x19, sp, #CTX_PAUTH_REGS_OFFSET
612
613	mrs	x20, APIAKeyLo_EL1	/* x21:x20 = APIAKey */
614	mrs	x21, APIAKeyHi_EL1
615	mrs	x22, APIBKeyLo_EL1	/* x23:x22 = APIBKey */
616	mrs	x23, APIBKeyHi_EL1
617	mrs	x24, APDAKeyLo_EL1	/* x25:x24 = APDAKey */
618	mrs	x25, APDAKeyHi_EL1
619	mrs	x26, APDBKeyLo_EL1	/* x27:x26 = APDBKey */
620	mrs	x27, APDBKeyHi_EL1
621	mrs	x28, APGAKeyLo_EL1	/* x29:x28 = APGAKey */
622	mrs	x29, APGAKeyHi_EL1
623
624	stp	x20, x21, [x19, #CTX_PACIAKEY_LO]
625	stp	x22, x23, [x19, #CTX_PACIBKEY_LO]
626	stp	x24, x25, [x19, #CTX_PACDAKEY_LO]
627	stp	x26, x27, [x19, #CTX_PACDBKEY_LO]
628	stp	x28, x29, [x19, #CTX_PACGAKEY_LO]
629#endif /* CTX_INCLUDE_PAUTH_REGS */
630	.endm /* save_gp_pmcr_pauth_regs */
631
632/* -----------------------------------------------------------------
633 * This function saves the context and sets the PSTATE to a known
634 * state, preparing entry to el3.
635 * Save all the general purpose and ARMv8.3-PAuth (if enabled)
636 * registers.
637 * Then set any of the PSTATE bits that are not set by hardware
638 * according to the Aarch64.TakeException pseudocode in the Arm
639 * Architecture Reference Manual to a default value for EL3.
640 * clobbers: x17
641 * -----------------------------------------------------------------
642 */
643func prepare_el3_entry
644	save_gp_pmcr_pauth_regs
645	enable_serror_at_el3
646	/*
647	 * Set the PSTATE bits not described in the Aarch64.TakeException
648	 * pseudocode to their default values.
649	 */
650	set_unset_pstate_bits
651	ret
652endfunc prepare_el3_entry
653
654/* ------------------------------------------------------------------
655 * This function restores ARMv8.3-PAuth (if enabled) and all general
656 * purpose registers except x30 from the CPU context.
657 * x30 register must be explicitly restored by the caller.
658 * ------------------------------------------------------------------
659 */
660func restore_gp_pmcr_pauth_regs
661#if CTX_INCLUDE_PAUTH_REGS
662 	/* Restore the ARMv8.3 PAuth keys */
663	add	x10, sp, #CTX_PAUTH_REGS_OFFSET
664
665	ldp	x0, x1, [x10, #CTX_PACIAKEY_LO]	/* x1:x0 = APIAKey */
666	ldp	x2, x3, [x10, #CTX_PACIBKEY_LO]	/* x3:x2 = APIBKey */
667	ldp	x4, x5, [x10, #CTX_PACDAKEY_LO]	/* x5:x4 = APDAKey */
668	ldp	x6, x7, [x10, #CTX_PACDBKEY_LO]	/* x7:x6 = APDBKey */
669	ldp	x8, x9, [x10, #CTX_PACGAKEY_LO]	/* x9:x8 = APGAKey */
670
671	msr	APIAKeyLo_EL1, x0
672	msr	APIAKeyHi_EL1, x1
673	msr	APIBKeyLo_EL1, x2
674	msr	APIBKeyHi_EL1, x3
675	msr	APDAKeyLo_EL1, x4
676	msr	APDAKeyHi_EL1, x5
677	msr	APDBKeyLo_EL1, x6
678	msr	APDBKeyHi_EL1, x7
679	msr	APGAKeyLo_EL1, x8
680	msr	APGAKeyHi_EL1, x9
681#endif /* CTX_INCLUDE_PAUTH_REGS */
682	ldr	x0, [sp, #CTX_EL3STATE_OFFSET + CTX_PMCR_EL0]
683	msr	pmcr_el0, x0
684	ldp	x0, x1, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X0]
685	ldp	x2, x3, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X2]
686	ldp	x4, x5, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X4]
687	ldp	x6, x7, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X6]
688	ldp	x8, x9, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X8]
689	ldp	x10, x11, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X10]
690	ldp	x12, x13, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X12]
691	ldp	x14, x15, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X14]
692	ldp	x16, x17, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X16]
693	ldp	x18, x19, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X18]
694	ldp	x20, x21, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X20]
695	ldp	x22, x23, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X22]
696	ldp	x24, x25, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X24]
697	ldp	x26, x27, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X26]
698	ldr	x28, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_SP_EL0]
699	msr	sp_el0, x28
700	ldp	x28, x29, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X28]
701	ret
702endfunc restore_gp_pmcr_pauth_regs
703
704/*
705 * In case of ERRATA_SPECULATIVE_AT, save SCTLR_EL1 and TCR_EL1
706 * registers and update EL1 registers to disable stage1 and stage2
707 * page table walk
708 */
709func save_and_update_ptw_el1_sys_regs
710	/* ----------------------------------------------------------
711	 * Save only sctlr_el1 and tcr_el1 registers
712	 * ----------------------------------------------------------
713	 */
714	mrs	x29, sctlr_el1
715	str	x29, [sp, #(CTX_EL1_SYSREGS_OFFSET + CTX_SCTLR_EL1)]
716	mrs	x29, tcr_el1
717	str	x29, [sp, #(CTX_EL1_SYSREGS_OFFSET + CTX_TCR_EL1)]
718
719	/* ------------------------------------------------------------
720	 * Must follow below order in order to disable page table
721	 * walk for lower ELs (EL1 and EL0). First step ensures that
722	 * page table walk is disabled for stage1 and second step
723	 * ensures that page table walker should use TCR_EL1.EPDx
724	 * bits to perform address translation. ISB ensures that CPU
725	 * does these 2 steps in order.
726	 *
727	 * 1. Update TCR_EL1.EPDx bits to disable page table walk by
728	 *    stage1.
729	 * 2. Enable MMU bit to avoid identity mapping via stage2
730	 *    and force TCR_EL1.EPDx to be used by the page table
731	 *    walker.
732	 * ------------------------------------------------------------
733	 */
734	orr	x29, x29, #(TCR_EPD0_BIT)
735	orr	x29, x29, #(TCR_EPD1_BIT)
736	msr	tcr_el1, x29
737	isb
738	mrs	x29, sctlr_el1
739	orr	x29, x29, #SCTLR_M_BIT
740	msr	sctlr_el1, x29
741	isb
742
743	ret
744endfunc save_and_update_ptw_el1_sys_regs
745
746/* ------------------------------------------------------------------
747 * This routine assumes that the SP_EL3 is pointing to a valid
748 * context structure from where the gp regs and other special
749 * registers can be retrieved.
750 * ------------------------------------------------------------------
751 */
752func el3_exit
753#if ENABLE_ASSERTIONS
754	/* el3_exit assumes SP_EL0 on entry */
755	mrs	x17, spsel
756	cmp	x17, #MODE_SP_EL0
757	ASM_ASSERT(eq)
758#endif /* ENABLE_ASSERTIONS */
759
760	/* ----------------------------------------------------------
761	 * Save the current SP_EL0 i.e. the EL3 runtime stack which
762	 * will be used for handling the next SMC.
763	 * Then switch to SP_EL3.
764	 * ----------------------------------------------------------
765	 */
766	mov	x17, sp
767	msr	spsel, #MODE_SP_ELX
768	str	x17, [sp, #CTX_EL3STATE_OFFSET + CTX_RUNTIME_SP]
769
770#if IMAGE_BL31
771	/* ----------------------------------------------------------
772	 * Restore CPTR_EL3.
773	 * ZCR is only restored if SVE is supported and enabled.
774	 * Synchronization is required before zcr_el3 is addressed.
775	 * ----------------------------------------------------------
776	 */
777	ldp	x19, x20, [sp, #CTX_EL3STATE_OFFSET + CTX_CPTR_EL3]
778	msr	cptr_el3, x19
779
780	ands	x19, x19, #CPTR_EZ_BIT
781	beq	sve_not_enabled
782
783	isb
784	msr	S3_6_C1_C2_0, x20 /* zcr_el3 */
785sve_not_enabled:
786#endif /* IMAGE_BL31 */
787
788#if IMAGE_BL31 && DYNAMIC_WORKAROUND_CVE_2018_3639
789	/* ----------------------------------------------------------
790	 * Restore mitigation state as it was on entry to EL3
791	 * ----------------------------------------------------------
792	 */
793	ldr	x17, [sp, #CTX_CVE_2018_3639_OFFSET + CTX_CVE_2018_3639_DISABLE]
794	cbz	x17, 1f
795	blr	x17
7961:
797#endif /* IMAGE_BL31 && DYNAMIC_WORKAROUND_CVE_2018_3639 */
798
799#if IMAGE_BL31 && RAS_EXTENSION
800	/* ----------------------------------------------------------
801	 * Issue Error Synchronization Barrier to synchronize SErrors
802	 * before exiting EL3. We're running with EAs unmasked, so
803	 * any synchronized errors would be taken immediately;
804	 * therefore no need to inspect DISR_EL1 register.
805 	 * ----------------------------------------------------------
806	 */
807	esb
808#else
809	dsb	sy
810#endif /* IMAGE_BL31 && RAS_EXTENSION */
811
812	/* ----------------------------------------------------------
813	 * Restore SPSR_EL3, ELR_EL3 and SCR_EL3 prior to ERET
814	 * ----------------------------------------------------------
815	 */
816	ldr	x18, [sp, #CTX_EL3STATE_OFFSET + CTX_SCR_EL3]
817	ldp	x16, x17, [sp, #CTX_EL3STATE_OFFSET + CTX_SPSR_EL3]
818	msr	scr_el3, x18
819	msr	spsr_el3, x16
820	msr	elr_el3, x17
821
822	restore_ptw_el1_sys_regs
823
824	/* ----------------------------------------------------------
825	 * Restore general purpose (including x30), PMCR_EL0 and
826	 * ARMv8.3-PAuth registers.
827	 * Exit EL3 via ERET to a lower exception level.
828 	 * ----------------------------------------------------------
829 	 */
830	bl	restore_gp_pmcr_pauth_regs
831	ldr	x30, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR]
832
833#ifdef IMAGE_BL31
834	str	xzr, [sp, #CTX_EL3STATE_OFFSET + CTX_IS_IN_EL3]
835#endif /* IMAGE_BL31 */
836
837	exception_return
838
839endfunc el3_exit
840