xref: /rk3399_ARM-atf/lib/psci/aarch64/psci_helpers.S (revision 67748e4827976f3b13f8bc1281b3c4b59da87e4a)
1/*
2 * Copyright (c) 2014-2016, ARM Limited and Contributors. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are met:
6 *
7 * Redistributions of source code must retain the above copyright notice, this
8 * list of conditions and the following disclaimer.
9 *
10 * Redistributions in binary form must reproduce the above copyright notice,
11 * this list of conditions and the following disclaimer in the documentation
12 * and/or other materials provided with the distribution.
13 *
14 * Neither the name of ARM nor the names of its contributors may be used
15 * to endorse or promote products derived from this software without specific
16 * prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include <asm_macros.S>
32#include <assert_macros.S>
33#include <platform_def.h>
34#include <psci.h>
35
36	.globl	psci_do_pwrdown_cache_maintenance
37	.globl	psci_do_pwrup_cache_maintenance
38	.globl	psci_power_down_wfi
39#if !ERROR_DEPRECATED
40	.globl psci_entrypoint
41#endif
42
43/* -----------------------------------------------------------------------
44 * void psci_do_pwrdown_cache_maintenance(unsigned int power level);
45 *
46 * This function performs cache maintenance for the specified power
47 * level. The levels of cache affected are determined by the power
48 * level which is passed as the argument i.e. level 0 results
49 * in a flush of the L1 cache. Both the L1 and L2 caches are flushed
50 * for a higher power level.
51 *
52 * Additionally, this function also ensures that stack memory is correctly
53 * flushed out to avoid coherency issues due to a change in its memory
54 * attributes after the data cache is disabled.
55 * -----------------------------------------------------------------------
56 */
57func psci_do_pwrdown_cache_maintenance
58	stp     x29, x30, [sp,#-16]!
59	stp     x19, x20, [sp,#-16]!
60
61	/* ---------------------------------------------
62	 * Invoke CPU-specific power down operations for
63	 * the appropriate level
64	 * ---------------------------------------------
65	 */
66	bl	prepare_cpu_pwr_dwn
67
68	/* ---------------------------------------------
69	 * Do stack maintenance by flushing the used
70	 * stack to the main memory and invalidating the
71	 * remainder.
72	 * ---------------------------------------------
73	 */
74	bl	plat_get_my_stack
75
76	/* ---------------------------------------------
77	 * Calculate and store the size of the used
78	 * stack memory in x1.
79	 * ---------------------------------------------
80	 */
81	mov	x19, x0
82	mov	x1, sp
83	sub	x1, x0, x1
84	mov	x0, sp
85	bl	flush_dcache_range
86
87	/* ---------------------------------------------
88	 * Calculate and store the size of the unused
89	 * stack memory in x1. Calculate and store the
90	 * stack base address in x0.
91	 * ---------------------------------------------
92	 */
93	sub	x0, x19, #PLATFORM_STACK_SIZE
94	sub	x1, sp, x0
95	bl	inv_dcache_range
96
97	ldp	x19, x20, [sp], #16
98	ldp	x29, x30, [sp], #16
99	ret
100endfunc psci_do_pwrdown_cache_maintenance
101
102
103/* -----------------------------------------------------------------------
104 * void psci_do_pwrup_cache_maintenance(void);
105 *
106 * This function performs cache maintenance after this cpu is powered up.
107 * Currently, this involves managing the used stack memory before turning
108 * on the data cache.
109 * -----------------------------------------------------------------------
110 */
111func psci_do_pwrup_cache_maintenance
112	stp	x29, x30, [sp,#-16]!
113
114	/* ---------------------------------------------
115	 * Ensure any inflight stack writes have made it
116	 * to main memory.
117	 * ---------------------------------------------
118	 */
119	dmb	st
120
121	/* ---------------------------------------------
122	 * Calculate and store the size of the used
123	 * stack memory in x1. Calculate and store the
124	 * stack base address in x0.
125	 * ---------------------------------------------
126	 */
127	bl	plat_get_my_stack
128	mov	x1, sp
129	sub	x1, x0, x1
130	mov	x0, sp
131	bl	inv_dcache_range
132
133	/* ---------------------------------------------
134	 * Enable the data cache.
135	 * ---------------------------------------------
136	 */
137	mrs	x0, sctlr_el3
138	orr	x0, x0, #SCTLR_C_BIT
139	msr	sctlr_el3, x0
140	isb
141
142	ldp	x29, x30, [sp], #16
143	ret
144endfunc psci_do_pwrup_cache_maintenance
145
146/* -----------------------------------------------------------------------
147 * void psci_power_down_wfi(void);
148 * This function is called to indicate to the power controller that it
149 * is safe to power down this cpu. It should not exit the wfi and will
150 * be released from reset upon power up.
151 * -----------------------------------------------------------------------
152 */
153func psci_power_down_wfi
154	dsb	sy		// ensure write buffer empty
155	wfi
156	no_ret	plat_panic_handler
157endfunc psci_power_down_wfi
158
159/* -----------------------------------------------------------------------
160 * void psci_entrypoint(void);
161 * The deprecated entry point for PSCI on warm boot for AArch64.
162 * -----------------------------------------------------------------------
163 */
164func_deprecated psci_entrypoint
165	b	bl31_warm_entrypoint
166endfunc_deprecated psci_entrypoint
167