xref: /rk3399_ARM-atf/lib/cpus/aarch32/cpu_helpers.S (revision f426fc0519103defb3dcf4a9d86d985d48204424)
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#if IMAGE_BL1 || IMAGE_BL32
38	/*
39	 * The reset handler common to all platforms.  After a matching
40	 * cpu_ops structure entry is found, the correponding reset_handler
41	 * in the cpu_ops is invoked. The reset handler is invoked very early
42	 * in the boot sequence and it is assumed that we can clobber r0 - r10
43	 * without the need to follow AAPCS.
44	 * Clobbers: r0 - r10
45	 */
46	.globl	reset_handler
47func reset_handler
48	mov	r10, lr
49
50	/* The plat_reset_handler can clobber r0 - r9 */
51	bl	plat_reset_handler
52
53	/* Get the matching cpu_ops pointer (clobbers: r0 - r5) */
54	bl	get_cpu_ops_ptr
55
56#if ASM_ASSERTION
57	cmp	r0, #0
58	ASM_ASSERT(ne)
59#endif
60
61	/* Get the cpu_ops reset handler */
62	ldr	r1, [r0, #CPU_RESET_FUNC]
63	cmp	r1, #0
64	mov	lr, r10
65	bxne	r1
66	bx	lr
67endfunc reset_handler
68
69#endif /* IMAGE_BL1 || IMAGE_BL32 */
70
71#if IMAGE_BL32 /* The power down core and cluster is needed only in  BL32 */
72	/*
73	 * The prepare core power down function for all platforms.  After
74	 * the cpu_ops pointer is retrieved from cpu_data, the corresponding
75	 * pwr_dwn_core in the cpu_ops is invoked. Follows AAPCS.
76	 */
77	.globl	prepare_core_pwr_dwn
78func prepare_core_pwr_dwn
79	push	{lr}
80	bl	_cpu_data
81	pop	{lr}
82
83	ldr	r1, [r0, #CPU_DATA_CPU_OPS_PTR]
84#if ASM_ASSERTION
85	cmp	r1, #0
86	ASM_ASSERT(ne)
87#endif
88
89	/* Get the cpu_ops core_pwr_dwn handler */
90	ldr	r0, [r1, #CPU_PWR_DWN_CORE]
91	bx	r0
92endfunc prepare_core_pwr_dwn
93
94	/*
95	 * The prepare cluster power down function for all platforms.  After
96	 * the cpu_ops pointer is retrieved from cpu_data, the corresponding
97	 * pwr_dwn_cluster in the cpu_ops is invoked. Follows AAPCS.
98	 */
99	.globl	prepare_cluster_pwr_dwn
100func prepare_cluster_pwr_dwn
101	push	{lr}
102	bl	_cpu_data
103	pop	{lr}
104
105	ldr	r1, [r0, #CPU_DATA_CPU_OPS_PTR]
106#if ASM_ASSERTION
107	cmp	r1, #0
108	ASM_ASSERT(ne)
109#endif
110
111	/* Get the cpu_ops cluster_pwr_dwn handler */
112	ldr	r0, [r1, #CPU_PWR_DWN_CLUSTER]
113	bx	r0
114endfunc prepare_cluster_pwr_dwn
115
116	/*
117	 * Initializes the cpu_ops_ptr if not already initialized
118	 * in cpu_data. This must only be called after the data cache
119	 * is enabled. AAPCS is followed.
120	 */
121	.globl	init_cpu_ops
122func init_cpu_ops
123	push	{r4 - r6, lr}
124	bl	_cpu_data
125	mov	r6, r0
126	ldr	r1, [r0, #CPU_DATA_CPU_OPS_PTR]
127	cmp	r1, #0
128	bne	1f
129	bl	get_cpu_ops_ptr
130#if ASM_ASSERTION
131	cmp	r0, #0
132	ASM_ASSERT(ne)
133#endif
134	str	r0, [r6, #CPU_DATA_CPU_OPS_PTR]!
1351:
136	pop	{r4 - r6, pc}
137endfunc init_cpu_ops
138
139#endif /* IMAGE_BL32 */
140
141	/*
142	 * The below function returns the cpu_ops structure matching the
143	 * midr of the core. It reads the MIDR and finds the matching
144	 * entry in cpu_ops entries. Only the implementation and part number
145	 * are used to match the entries.
146	 * Return :
147	 *     r0 - The matching cpu_ops pointer on Success
148	 *     r0 - 0 on failure.
149	 * Clobbers: r0 - r5
150	 */
151	.globl	get_cpu_ops_ptr
152func get_cpu_ops_ptr
153	/* Get the cpu_ops start and end locations */
154	ldr	r4, =(__CPU_OPS_START__ + CPU_MIDR)
155	ldr	r5, =(__CPU_OPS_END__ + CPU_MIDR)
156
157	/* Initialize the return parameter */
158	mov	r0, #0
159
160	/* Read the MIDR_EL1 */
161	ldcopr	r2, MIDR
162	ldr	r3, =CPU_IMPL_PN_MASK
163
164	/* Retain only the implementation and part number using mask */
165	and	r2, r2, r3
1661:
167	/* Check if we have reached end of list */
168	cmp	r4, r5
169	bge	error_exit
170
171	/* load the midr from the cpu_ops */
172	ldr	r1, [r4], #CPU_OPS_SIZE
173	and	r1, r1, r3
174
175	/* Check if midr matches to midr of this core */
176	cmp	r1, r2
177	bne	1b
178
179	/* Subtract the increment and offset to get the cpu-ops pointer */
180	sub	r0, r4, #(CPU_OPS_SIZE + CPU_MIDR)
181error_exit:
182	bx	lr
183endfunc get_cpu_ops_ptr
184