xref: /OK3568_Linux_fs/u-boot/arch/arm/cpu/sa1100/start.S (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun/*
2*4882a593Smuzhiyun *  armboot - Startup Code for SA1100 CPU
3*4882a593Smuzhiyun *
4*4882a593Smuzhiyun *  Copyright (C) 1998	Dan Malek <dmalek@jlc.net>
5*4882a593Smuzhiyun *  Copyright (C) 1999	Magnus Damm <kieraypc01.p.y.kie.era.ericsson.se>
6*4882a593Smuzhiyun *  Copyright (C) 2000	Wolfgang Denk <wd@denx.de>
7*4882a593Smuzhiyun *  Copyright (c) 2001	Alex Züpke <azu@sysgo.de>
8*4882a593Smuzhiyun *
9*4882a593Smuzhiyun * SPDX-License-Identifier:	GPL-2.0+
10*4882a593Smuzhiyun */
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun#include <asm-offsets.h>
13*4882a593Smuzhiyun#include <config.h>
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun/*
16*4882a593Smuzhiyun *************************************************************************
17*4882a593Smuzhiyun *
18*4882a593Smuzhiyun * Startup Code (reset vector)
19*4882a593Smuzhiyun *
20*4882a593Smuzhiyun * do important init only if we don't start from memory!
21*4882a593Smuzhiyun * relocate armboot to ram
22*4882a593Smuzhiyun * setup stack
23*4882a593Smuzhiyun * jump to second stage
24*4882a593Smuzhiyun *
25*4882a593Smuzhiyun *************************************************************************
26*4882a593Smuzhiyun */
27*4882a593Smuzhiyun
28*4882a593Smuzhiyun	.globl	reset
29*4882a593Smuzhiyun
30*4882a593Smuzhiyunreset:
31*4882a593Smuzhiyun	/*
32*4882a593Smuzhiyun	 * set the cpu to SVC32 mode
33*4882a593Smuzhiyun	 */
34*4882a593Smuzhiyun	mrs	r0,cpsr
35*4882a593Smuzhiyun	bic	r0,r0,#0x1f
36*4882a593Smuzhiyun	orr	r0,r0,#0xd3
37*4882a593Smuzhiyun	msr	cpsr,r0
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun	/*
40*4882a593Smuzhiyun	 * we do sys-critical inits only at reboot,
41*4882a593Smuzhiyun	 * not when booting from ram!
42*4882a593Smuzhiyun	 */
43*4882a593Smuzhiyun#ifndef CONFIG_SKIP_LOWLEVEL_INIT
44*4882a593Smuzhiyun	bl	cpu_init_crit
45*4882a593Smuzhiyun#endif
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun	bl	_main
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun/*------------------------------------------------------------------------------*/
50*4882a593Smuzhiyun
51*4882a593Smuzhiyun	.globl	c_runtime_cpu_setup
52*4882a593Smuzhiyunc_runtime_cpu_setup:
53*4882a593Smuzhiyun
54*4882a593Smuzhiyun	mov	pc, lr
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun/*
57*4882a593Smuzhiyun *************************************************************************
58*4882a593Smuzhiyun *
59*4882a593Smuzhiyun * CPU_init_critical registers
60*4882a593Smuzhiyun *
61*4882a593Smuzhiyun * setup important registers
62*4882a593Smuzhiyun * setup memory timing
63*4882a593Smuzhiyun *
64*4882a593Smuzhiyun *************************************************************************
65*4882a593Smuzhiyun */
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun
68*4882a593Smuzhiyun/* Interrupt-Controller base address */
69*4882a593SmuzhiyunIC_BASE:	.word	0x90050000
70*4882a593Smuzhiyun#define ICMR	0x04
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun
73*4882a593Smuzhiyun/* Reset-Controller */
74*4882a593SmuzhiyunRST_BASE:		.word   0x90030000
75*4882a593Smuzhiyun#define RSRR	0x00
76*4882a593Smuzhiyun#define RCSR	0x04
77*4882a593Smuzhiyun
78*4882a593Smuzhiyun
79*4882a593Smuzhiyun/* PWR */
80*4882a593SmuzhiyunPWR_BASE:		.word   0x90020000
81*4882a593Smuzhiyun#define PSPR    0x08
82*4882a593Smuzhiyun#define PPCR    0x14
83*4882a593Smuzhiyuncpuspeed:		.word   CONFIG_SYS_CPUSPEED
84*4882a593Smuzhiyun
85*4882a593Smuzhiyun
86*4882a593Smuzhiyuncpu_init_crit:
87*4882a593Smuzhiyun	/*
88*4882a593Smuzhiyun	 * mask all IRQs
89*4882a593Smuzhiyun	 */
90*4882a593Smuzhiyun	ldr	r0, IC_BASE
91*4882a593Smuzhiyun	mov	r1, #0x00
92*4882a593Smuzhiyun	str	r1, [r0, #ICMR]
93*4882a593Smuzhiyun
94*4882a593Smuzhiyun	/* set clock speed */
95*4882a593Smuzhiyun	ldr	r0, PWR_BASE
96*4882a593Smuzhiyun	ldr	r1, cpuspeed
97*4882a593Smuzhiyun	str	r1, [r0, #PPCR]
98*4882a593Smuzhiyun
99*4882a593Smuzhiyun#ifndef CONFIG_SKIP_LOWLEVEL_INIT_ONLY
100*4882a593Smuzhiyun	/*
101*4882a593Smuzhiyun	 * before relocating, we have to setup RAM timing
102*4882a593Smuzhiyun	 * because memory timing is board-dependend, you will
103*4882a593Smuzhiyun	 * find a lowlevel_init.S in your board directory.
104*4882a593Smuzhiyun	 */
105*4882a593Smuzhiyun	mov	ip,	lr
106*4882a593Smuzhiyun	bl	lowlevel_init
107*4882a593Smuzhiyun	mov	lr,	ip
108*4882a593Smuzhiyun#endif
109*4882a593Smuzhiyun
110*4882a593Smuzhiyun	/*
111*4882a593Smuzhiyun	 * disable MMU stuff and enable I-cache
112*4882a593Smuzhiyun	 */
113*4882a593Smuzhiyun	mrc	p15,0,r0,c1,c0
114*4882a593Smuzhiyun	bic	r0, r0, #0x00002000	@ clear bit 13 (X)
115*4882a593Smuzhiyun	bic	r0, r0, #0x0000000f	@ clear bits 3-0 (WCAM)
116*4882a593Smuzhiyun	orr	r0, r0, #0x00001000	@ set bit 12 (I) Icache
117*4882a593Smuzhiyun	orr	r0, r0, #0x00000002	@ set bit 1 (A) Align
118*4882a593Smuzhiyun	mcr	p15,0,r0,c1,c0
119*4882a593Smuzhiyun
120*4882a593Smuzhiyun	/*
121*4882a593Smuzhiyun	 * flush v4 I/D caches
122*4882a593Smuzhiyun	 */
123*4882a593Smuzhiyun	mov	r0, #0
124*4882a593Smuzhiyun	mcr	p15, 0, r0, c7, c7, 0	/* flush v3/v4 cache */
125*4882a593Smuzhiyun	mcr	p15, 0, r0, c8, c7, 0	/* flush v4 TLB */
126*4882a593Smuzhiyun
127*4882a593Smuzhiyun	mov	pc, lr
128