xref: /rk3399_ARM-atf/plat/arm/board/fvp/aarch32/fvp_helpers.S (revision 7a3d4bdeefe361d8b88d0a62251df768a73684b3)
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 <platform_def.h>
34#include "../drivers/pwrc/fvp_pwrc.h"
35#include "../fvp_def.h"
36
37	.globl	plat_get_my_entrypoint
38	.globl	plat_is_my_cpu_primary
39
40	/* ---------------------------------------------------------------------
41	 * unsigned long plat_get_my_entrypoint (void);
42	 *
43	 * Main job of this routine is to distinguish between a cold and warm
44	 * boot. On FVP, this information can be queried from the power
45	 * controller. The Power Control SYS Status Register (PSYSR) indicates
46	 * the wake-up reason for the CPU.
47	 *
48	 * For a cold boot, return 0.
49	 * For a warm boot, read the mailbox and return the address it contains.
50	 *
51	 * TODO: PSYSR is a common register and should be
52	 * 	accessed using locks. Since it is not possible
53	 * 	to use locks immediately after a cold reset
54	 * 	we are relying on the fact that after a cold
55	 * 	reset all cpus will read the same WK field
56	 * ---------------------------------------------------------------------
57	 */
58func plat_get_my_entrypoint
59	/* ---------------------------------------------------------------------
60	 * When bit PSYSR.WK indicates either "Wake by PPONR" or "Wake by GIC
61	 * WakeRequest signal" then it is a warm boot.
62	 * ---------------------------------------------------------------------
63	 */
64	ldcopr	r2, MPIDR
65	ldr	r1, =PWRC_BASE
66	str	r2, [r1, #PSYSR_OFF]
67	ldr	r2, [r1, #PSYSR_OFF]
68	ubfx	r2, r2, #PSYSR_WK_SHIFT, #PSYSR_WK_WIDTH
69	cmp	r2, #WKUP_PPONR
70	beq	warm_reset
71	cmp	r2, #WKUP_GICREQ
72	beq	warm_reset
73
74	/* Cold reset */
75	mov	r0, #0
76	bx	lr
77
78warm_reset:
79	/* ---------------------------------------------------------------------
80	 * A mailbox is maintained in the trusted SRAM. It is flushed out of the
81	 * caches after every update using normal memory so it is safe to read
82	 * it here with SO attributes.
83	 * ---------------------------------------------------------------------
84	 */
85	ldr	r0, =PLAT_ARM_TRUSTED_MAILBOX_BASE
86	ldr	r0, [r0]
87	cmp	r0, #0
88	beq	_panic
89	bx	lr
90
91	/* ---------------------------------------------------------------------
92	 * The power controller indicates this is a warm reset but the mailbox
93	 * is empty. This should never happen!
94	 * ---------------------------------------------------------------------
95	 */
96_panic:
97	b	_panic
98endfunc plat_get_my_entrypoint
99
100	/* -----------------------------------------------------
101	 * unsigned int plat_is_my_cpu_primary (void);
102	 *
103	 * Find out whether the current cpu is the primary
104	 * cpu.
105	 * -----------------------------------------------------
106	 */
107func plat_is_my_cpu_primary
108	ldcopr	r0, MPIDR
109	ldr	r1, =(MPIDR_CLUSTER_MASK | MPIDR_CPU_MASK)
110	and	r0, r1
111	cmp	r0, #FVP_PRIMARY_CPU
112	moveq	r0, #1
113	movne	r0, #0
114	bx	lr
115endfunc plat_is_my_cpu_primary
116