xref: /rk3399_ARM-atf/lib/cpus/aarch32/cpu_helpers.S (revision 9f3ee61c904e4b6d2038086718c5ec4237d544a8)
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	/* r12 is pushed to meet the 8 byte stack alignment requirement */
80	push	{r12, lr}
81	bl	_cpu_data
82	pop	{r12, lr}
83
84	ldr	r1, [r0, #CPU_DATA_CPU_OPS_PTR]
85#if ASM_ASSERTION
86	cmp	r1, #0
87	ASM_ASSERT(ne)
88#endif
89
90	/* Get the cpu_ops core_pwr_dwn handler */
91	ldr	r0, [r1, #CPU_PWR_DWN_CORE]
92	bx	r0
93endfunc prepare_core_pwr_dwn
94
95	/*
96	 * The prepare cluster power down function for all platforms.  After
97	 * the cpu_ops pointer is retrieved from cpu_data, the corresponding
98	 * pwr_dwn_cluster in the cpu_ops is invoked. Follows AAPCS.
99	 */
100	.globl	prepare_cluster_pwr_dwn
101func prepare_cluster_pwr_dwn
102	/* r12 is pushed to meet the 8 byte stack alignment requirement */
103	push	{r12, lr}
104	bl	_cpu_data
105	pop	{r12, lr}
106
107	ldr	r1, [r0, #CPU_DATA_CPU_OPS_PTR]
108#if ASM_ASSERTION
109	cmp	r1, #0
110	ASM_ASSERT(ne)
111#endif
112
113	/* Get the cpu_ops cluster_pwr_dwn handler */
114	ldr	r0, [r1, #CPU_PWR_DWN_CLUSTER]
115	bx	r0
116endfunc prepare_cluster_pwr_dwn
117
118	/*
119	 * Initializes the cpu_ops_ptr if not already initialized
120	 * in cpu_data. This must only be called after the data cache
121	 * is enabled. AAPCS is followed.
122	 */
123	.globl	init_cpu_ops
124func init_cpu_ops
125	push	{r4 - r6, lr}
126	bl	_cpu_data
127	mov	r6, r0
128	ldr	r1, [r0, #CPU_DATA_CPU_OPS_PTR]
129	cmp	r1, #0
130	bne	1f
131	bl	get_cpu_ops_ptr
132#if ASM_ASSERTION
133	cmp	r0, #0
134	ASM_ASSERT(ne)
135#endif
136	str	r0, [r6, #CPU_DATA_CPU_OPS_PTR]!
1371:
138	pop	{r4 - r6, pc}
139endfunc init_cpu_ops
140
141#endif /* IMAGE_BL32 */
142
143	/*
144	 * The below function returns the cpu_ops structure matching the
145	 * midr of the core. It reads the MIDR and finds the matching
146	 * entry in cpu_ops entries. Only the implementation and part number
147	 * are used to match the entries.
148	 * Return :
149	 *     r0 - The matching cpu_ops pointer on Success
150	 *     r0 - 0 on failure.
151	 * Clobbers: r0 - r5
152	 */
153	.globl	get_cpu_ops_ptr
154func get_cpu_ops_ptr
155	/* Get the cpu_ops start and end locations */
156	ldr	r4, =(__CPU_OPS_START__ + CPU_MIDR)
157	ldr	r5, =(__CPU_OPS_END__ + CPU_MIDR)
158
159	/* Initialize the return parameter */
160	mov	r0, #0
161
162	/* Read the MIDR_EL1 */
163	ldcopr	r2, MIDR
164	ldr	r3, =CPU_IMPL_PN_MASK
165
166	/* Retain only the implementation and part number using mask */
167	and	r2, r2, r3
1681:
169	/* Check if we have reached end of list */
170	cmp	r4, r5
171	bge	error_exit
172
173	/* load the midr from the cpu_ops */
174	ldr	r1, [r4], #CPU_OPS_SIZE
175	and	r1, r1, r3
176
177	/* Check if midr matches to midr of this core */
178	cmp	r1, r2
179	bne	1b
180
181	/* Subtract the increment and offset to get the cpu-ops pointer */
182	sub	r0, r4, #(CPU_OPS_SIZE + CPU_MIDR)
183error_exit:
184	bx	lr
185endfunc get_cpu_ops_ptr
186