xref: /rk3399_ARM-atf/lib/cpus/aarch32/cpu_helpers.S (revision 727e5238fa3e9220d6a2718fab3b1df22af1dc61)
1/*
2 * Copyright (c) 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 <arch.h>
32#include <asm_macros.S>
33#include <assert_macros.S>
34#include <cpu_data.h>
35#include <cpu_macros.S>
36
37	/*
38	 * The reset handler common to all platforms.  After a matching
39	 * cpu_ops structure entry is found, the correponding reset_handler
40	 * in the cpu_ops is invoked. The reset handler is invoked very early
41	 * in the boot sequence and it is assumed that we can clobber r0 - r10
42	 * without the need to follow AAPCS.
43	 * Clobbers: r0 - r10
44	 */
45	.globl	reset_handler
46func reset_handler
47	mov	r10, lr
48
49	/* The plat_reset_handler can clobber r0 - r9 */
50	bl	plat_reset_handler
51
52	/* Get the matching cpu_ops pointer (clobbers: r0 - r5) */
53	bl	get_cpu_ops_ptr
54
55#if ASM_ASSERTION
56	cmp	r0, #0
57	ASM_ASSERT(ne)
58#endif
59
60	/* Get the cpu_ops reset handler */
61	ldr	r1, [r0, #CPU_RESET_FUNC]
62	cmp	r1, #0
63	mov	lr, r10
64	bxne	r1
65	bx	lr
66endfunc reset_handler
67
68	/*
69	 * The prepare core power down function for all platforms.  After
70	 * the cpu_ops pointer is retrieved from cpu_data, the corresponding
71	 * pwr_dwn_core in the cpu_ops is invoked. Follows AAPCS.
72	 */
73	.globl	prepare_core_pwr_dwn
74func prepare_core_pwr_dwn
75	push	{lr}
76	bl	_cpu_data
77	pop	{lr}
78
79	ldr	r1, [r0, #CPU_DATA_CPU_OPS_PTR]
80#if ASM_ASSERTION
81	cmp	r1, #0
82	ASM_ASSERT(ne)
83#endif
84
85	/* Get the cpu_ops core_pwr_dwn handler */
86	ldr	r0, [r1, #CPU_PWR_DWN_CORE]
87	bx	r0
88endfunc prepare_core_pwr_dwn
89
90	/*
91	 * The prepare cluster power down function for all platforms.  After
92	 * the cpu_ops pointer is retrieved from cpu_data, the corresponding
93	 * pwr_dwn_cluster in the cpu_ops is invoked. Follows AAPCS.
94	 */
95	.globl	prepare_cluster_pwr_dwn
96func prepare_cluster_pwr_dwn
97	push	{lr}
98	bl	_cpu_data
99	pop	{lr}
100
101	ldr	r1, [r0, #CPU_DATA_CPU_OPS_PTR]
102#if ASM_ASSERTION
103	cmp	r1, #0
104	ASM_ASSERT(ne)
105#endif
106
107	/* Get the cpu_ops cluster_pwr_dwn handler */
108	ldr	r0, [r1, #CPU_PWR_DWN_CLUSTER]
109	bx	r0
110endfunc prepare_cluster_pwr_dwn
111
112	/*
113	 * Initializes the cpu_ops_ptr if not already initialized
114	 * in cpu_data. This must only be called after the data cache
115	 * is enabled. AAPCS is followed.
116	 */
117	.globl	init_cpu_ops
118func init_cpu_ops
119	push	{r4 - r6, lr}
120	bl	_cpu_data
121	mov	r6, r0
122	ldr	r1, [r0, #CPU_DATA_CPU_OPS_PTR]
123	cmp	r1, #0
124	bne	1f
125	bl	get_cpu_ops_ptr
126#if ASM_ASSERTION
127	cmp	r0, #0
128	ASM_ASSERT(ne)
129#endif
130	str	r0, [r6, #CPU_DATA_CPU_OPS_PTR]!
1311:
132	pop	{r4 - r6, pc}
133endfunc init_cpu_ops
134
135	/*
136	 * The below function returns the cpu_ops structure matching the
137	 * midr of the core. It reads the MIDR and finds the matching
138	 * entry in cpu_ops entries. Only the implementation and part number
139	 * are used to match the entries.
140	 * Return :
141	 *     r0 - The matching cpu_ops pointer on Success
142	 *     r0 - 0 on failure.
143	 * Clobbers: r0 - r5
144	 */
145	.globl	get_cpu_ops_ptr
146func get_cpu_ops_ptr
147	/* Get the cpu_ops start and end locations */
148	ldr	r4, =(__CPU_OPS_START__ + CPU_MIDR)
149	ldr	r5, =(__CPU_OPS_END__ + CPU_MIDR)
150
151	/* Initialize the return parameter */
152	mov	r0, #0
153
154	/* Read the MIDR_EL1 */
155	ldcopr	r2, MIDR
156	ldr	r3, =CPU_IMPL_PN_MASK
157
158	/* Retain only the implementation and part number using mask */
159	and	r2, r2, r3
1601:
161	/* Check if we have reached end of list */
162	cmp	r4, r5
163	bge	error_exit
164
165	/* load the midr from the cpu_ops */
166	ldr	r1, [r4], #CPU_OPS_SIZE
167	and	r1, r1, r3
168
169	/* Check if midr matches to midr of this core */
170	cmp	r1, r2
171	bne	1b
172
173	/* Subtract the increment and offset to get the cpu-ops pointer */
174	sub	r0, r4, #(CPU_OPS_SIZE + CPU_MIDR)
175error_exit:
176	bx	lr
177endfunc get_cpu_ops_ptr
178