xref: /openbmc/u-boot/arch/arm/cpu/arm1176/start.S (revision cd23aac4)
1/*
2 *  armboot - Startup Code for ARM1176 CPU-core
3 *
4 * Copyright (c) 2007	Samsung Electronics
5 *
6 * Copyright (C) 2008
7 * Guennadi Liakhovetki, DENX Software Engineering, <lg@denx.de>
8 *
9 * SPDX-License-Identifier:	GPL-2.0+
10 *
11 * 2007-09-21 - Restructured codes by jsgood (jsgood.yang@samsung.com)
12 * 2007-09-21 - Added MoviNAND and OneNAND boot codes by
13 * jsgood (jsgood.yang@samsung.com)
14 * Base codes by scsuh (sc.suh)
15 */
16
17#include <asm-offsets.h>
18#include <config.h>
19#include <version.h>
20
21#ifndef CONFIG_SYS_PHY_UBOOT_BASE
22#define CONFIG_SYS_PHY_UBOOT_BASE	CONFIG_SYS_UBOOT_BASE
23#endif
24
25/*
26 *************************************************************************
27 *
28 * Startup Code (reset vector)
29 *
30 * do important init only if we don't start from memory!
31 * setup Memory and board specific bits prior to relocation.
32 * relocate armboot to ram
33 * setup stack
34 *
35 *************************************************************************
36 */
37
38	.globl reset
39
40reset:
41	/*
42	 * set the cpu to SVC32 mode
43	 */
44	mrs	r0, cpsr
45	bic	r0, r0, #0x3f
46	orr	r0, r0, #0xd3
47	msr	cpsr, r0
48
49/*
50 *************************************************************************
51 *
52 * CPU_init_critical registers
53 *
54 * setup important registers
55 * setup memory timing
56 *
57 *************************************************************************
58 */
59	/*
60	 * we do sys-critical inits only at reboot,
61	 * not when booting from ram!
62	 */
63cpu_init_crit:
64	/*
65	 * When booting from NAND - it has definitely been a reset, so, no need
66	 * to flush caches and disable the MMU
67	 */
68#ifndef CONFIG_SPL_BUILD
69	/*
70	 * flush v4 I/D caches
71	 */
72	mov	r0, #0
73	mcr	p15, 0, r0, c7, c7, 0	/* flush v3/v4 cache */
74	mcr	p15, 0, r0, c8, c7, 0	/* flush v4 TLB */
75
76	/*
77	 * disable MMU stuff and caches
78	 */
79	mrc	p15, 0, r0, c1, c0, 0
80	bic	r0, r0, #0x00002300	@ clear bits 13, 9:8 (--V- --RS)
81	bic	r0, r0, #0x00000087	@ clear bits 7, 2:0 (B--- -CAM)
82	orr	r0, r0, #0x00000002	@ set bit 2 (A) Align
83	orr	r0, r0, #0x00001000	@ set bit 12 (I) I-Cache
84
85	/* Prepare to disable the MMU */
86	adr	r2, mmu_disable_phys
87	sub	r2, r2, #(CONFIG_SYS_PHY_UBOOT_BASE - CONFIG_SYS_TEXT_BASE)
88	b	mmu_disable
89
90	.align 5
91	/* Run in a single cache-line */
92mmu_disable:
93	mcr	p15, 0, r0, c1, c0, 0
94	nop
95	nop
96	mov	pc, r2
97mmu_disable_phys:
98
99#ifdef CONFIG_DISABLE_TCM
100	/*
101	 * Disable the TCMs
102	 */
103	mrc	p15, 0, r0, c0, c0, 2	/* Return TCM details */
104	cmp	r0, #0
105	beq	skip_tcmdisable
106	mov	r1, #0
107	mov	r2, #1
108	tst	r0, r2
109	mcrne	p15, 0, r1, c9, c1, 1	/* Disable Instruction TCM if present*/
110	tst	r0, r2, LSL #16
111	mcrne	p15, 0, r1, c9, c1, 0	/* Disable Data TCM if present*/
112skip_tcmdisable:
113#endif
114#endif
115
116#ifdef CONFIG_PERIPORT_REMAP
117	/* Peri port setup */
118	ldr	r0, =CONFIG_PERIPORT_BASE
119	orr	r0, r0, #CONFIG_PERIPORT_SIZE
120	mcr	p15,0,r0,c15,c2,4
121#endif
122
123	/*
124	 * Go setup Memory and board specific bits prior to relocation.
125	 */
126	bl	lowlevel_init		/* go setup pll,mux,memory */
127
128	bl	_main
129
130/*------------------------------------------------------------------------------*/
131
132	.globl	c_runtime_cpu_setup
133c_runtime_cpu_setup:
134
135	mov	pc, lr
136