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1/*
2 * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6#ifndef __SMCC_MACROS_S__
7#define __SMCC_MACROS_S__
8
9#include <arch.h>
10
11/*
12 * Macro to save the General purpose registers (r0 - r12), the banked
13 * spsr, lr, sp registers and the `scr` register to the SMC context on entry
14 * due a SMC call. The `lr` of the current mode (monitor) is expected to be
15 * already saved. The `sp` must point to the `smc_ctx_t` to save to.
16 * Additionally, also save the 'pmcr' register as this is updated whilst
17 * executing in the secure world.
18 */
19	.macro smcc_save_gp_mode_regs
20	/* Save r0 - r12 in the SMC context */
21	stm	sp, {r0-r12}
22	mov	r0, sp
23	add	r0, r0, #SMC_CTX_SP_USR
24
25	/* Save the banked registers including the current SPSR and LR */
26	mrs	r4, sp_usr
27	mrs	r5, lr_usr
28	mrs	r6, spsr_irq
29	mrs	r7, sp_irq
30	mrs	r8, lr_irq
31	mrs	r9, spsr_fiq
32	mrs	r10, sp_fiq
33	mrs	r11, lr_fiq
34	mrs	r12, spsr_svc
35	stm	r0!, {r4-r12}
36
37	mrs	r4, sp_svc
38	mrs	r5, lr_svc
39	mrs	r6, spsr_abt
40	mrs	r7, sp_abt
41	mrs	r8, lr_abt
42	mrs	r9, spsr_und
43	mrs	r10, sp_und
44	mrs	r11, lr_und
45	mrs	r12, spsr
46	stm	r0!, {r4-r12}
47
48	/* lr_mon is already saved by caller */
49	ldcopr	r4, SCR
50	str	r4, [sp, #SMC_CTX_SCR]
51	ldcopr	r4, PMCR
52	str	r4, [sp, #SMC_CTX_PMCR]
53	.endm
54
55/*
56 * Macro to restore the `smc_ctx_t`, which includes the General purpose
57 * registers and banked mode registers, and exit from the monitor mode.
58 * r0 must point to the `smc_ctx_t` to restore from.
59 */
60	.macro monitor_exit
61	/*
62	 * Save the current sp and restore the smc context
63	 * pointer to sp which will be used for handling the
64	 * next SMC.
65	 */
66	str	sp, [r0, #SMC_CTX_SP_MON]
67	mov	sp, r0
68
69	/*
70	 * Restore SCR first so that we access the right banked register
71	 * when the other mode registers are restored.
72	 */
73	ldr	r1, [r0, #SMC_CTX_SCR]
74	stcopr	r1, SCR
75	isb
76
77	/*
78	 * Restore the PMCR register.
79	 */
80	ldr	r1, [r0, #SMC_CTX_PMCR]
81	stcopr	r1, PMCR
82
83	/* Restore the banked registers including the current SPSR */
84	add	r1, r0, #SMC_CTX_SP_USR
85	ldm	r1!, {r4-r12}
86	msr	sp_usr, r4
87	msr	lr_usr, r5
88	msr	spsr_irq, r6
89	msr	sp_irq, r7
90	msr	lr_irq, r8
91	msr	spsr_fiq, r9
92	msr	sp_fiq, r10
93	msr	lr_fiq, r11
94	msr	spsr_svc, r12
95
96	ldm	r1!, {r4-r12}
97	msr	sp_svc, r4
98	msr	lr_svc, r5
99	msr	spsr_abt, r6
100	msr	sp_abt, r7
101	msr	lr_abt, r8
102	msr	spsr_und, r9
103	msr	sp_und, r10
104	msr	lr_und, r11
105	/*
106	 * Use the `_fsxc` suffix explicitly to instruct the assembler
107	 * to update all the 32 bits of SPSR. Else, by default, the
108	 * assembler assumes `_fc` suffix which only modifies
109	 * f->[31:24] and c->[7:0] bits of SPSR.
110	 */
111	msr	spsr_fsxc, r12
112
113	/* Restore the LR */
114	ldr	lr, [r0, #SMC_CTX_LR_MON]
115
116	/* Restore the rest of the general purpose registers */
117	ldm	r0, {r0-r12}
118	eret
119	.endm
120
121#endif /* __SMCC_MACROS_S__ */
122