xref: /OK3568_Linux_fs/u-boot/arch/arm/cpu/arm1176/start.S (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun/*
2*4882a593Smuzhiyun *  armboot - Startup Code for ARM1176 CPU-core
3*4882a593Smuzhiyun *
4*4882a593Smuzhiyun * Copyright (c) 2007	Samsung Electronics
5*4882a593Smuzhiyun *
6*4882a593Smuzhiyun * Copyright (C) 2008
7*4882a593Smuzhiyun * Guennadi Liakhovetki, DENX Software Engineering, <lg@denx.de>
8*4882a593Smuzhiyun *
9*4882a593Smuzhiyun * SPDX-License-Identifier:	GPL-2.0+
10*4882a593Smuzhiyun *
11*4882a593Smuzhiyun * 2007-09-21 - Restructured codes by jsgood (jsgood.yang@samsung.com)
12*4882a593Smuzhiyun * 2007-09-21 - Added MoviNAND and OneNAND boot codes by
13*4882a593Smuzhiyun * jsgood (jsgood.yang@samsung.com)
14*4882a593Smuzhiyun * Base codes by scsuh (sc.suh)
15*4882a593Smuzhiyun */
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun#include <asm-offsets.h>
18*4882a593Smuzhiyun#include <config.h>
19*4882a593Smuzhiyun#include <linux/linkage.h>
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun#ifndef CONFIG_SYS_PHY_UBOOT_BASE
22*4882a593Smuzhiyun#define CONFIG_SYS_PHY_UBOOT_BASE	CONFIG_SYS_UBOOT_BASE
23*4882a593Smuzhiyun#endif
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun/*
26*4882a593Smuzhiyun *************************************************************************
27*4882a593Smuzhiyun *
28*4882a593Smuzhiyun * Startup Code (reset vector)
29*4882a593Smuzhiyun *
30*4882a593Smuzhiyun * do important init only if we don't start from memory!
31*4882a593Smuzhiyun * setup Memory and board specific bits prior to relocation.
32*4882a593Smuzhiyun * relocate armboot to ram
33*4882a593Smuzhiyun * setup stack
34*4882a593Smuzhiyun *
35*4882a593Smuzhiyun *************************************************************************
36*4882a593Smuzhiyun */
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun	.globl reset
39*4882a593Smuzhiyun
40*4882a593Smuzhiyunreset:
41*4882a593Smuzhiyun	/* Allow the board to save important registers */
42*4882a593Smuzhiyun	b	save_boot_params
43*4882a593Smuzhiyun.globl	save_boot_params_ret
44*4882a593Smuzhiyunsave_boot_params_ret:
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun	/*
47*4882a593Smuzhiyun	 * set the cpu to SVC32 mode
48*4882a593Smuzhiyun	 */
49*4882a593Smuzhiyun	mrs	r0, cpsr
50*4882a593Smuzhiyun	bic	r0, r0, #0x3f
51*4882a593Smuzhiyun	orr	r0, r0, #0xd3
52*4882a593Smuzhiyun	msr	cpsr, r0
53*4882a593Smuzhiyun
54*4882a593Smuzhiyun/*
55*4882a593Smuzhiyun *************************************************************************
56*4882a593Smuzhiyun *
57*4882a593Smuzhiyun * CPU_init_critical registers
58*4882a593Smuzhiyun *
59*4882a593Smuzhiyun * setup important registers
60*4882a593Smuzhiyun * setup memory timing
61*4882a593Smuzhiyun *
62*4882a593Smuzhiyun *************************************************************************
63*4882a593Smuzhiyun */
64*4882a593Smuzhiyun	/*
65*4882a593Smuzhiyun	 * we do sys-critical inits only at reboot,
66*4882a593Smuzhiyun	 * not when booting from ram!
67*4882a593Smuzhiyun	 */
68*4882a593Smuzhiyuncpu_init_crit:
69*4882a593Smuzhiyun	/*
70*4882a593Smuzhiyun	 * When booting from NAND - it has definitely been a reset, so, no need
71*4882a593Smuzhiyun	 * to flush caches and disable the MMU
72*4882a593Smuzhiyun	 */
73*4882a593Smuzhiyun#ifndef CONFIG_SPL_BUILD
74*4882a593Smuzhiyun	/*
75*4882a593Smuzhiyun	 * flush v4 I/D caches
76*4882a593Smuzhiyun	 */
77*4882a593Smuzhiyun	mov	r0, #0
78*4882a593Smuzhiyun	mcr	p15, 0, r0, c7, c7, 0	/* flush v3/v4 cache */
79*4882a593Smuzhiyun	mcr	p15, 0, r0, c8, c7, 0	/* flush v4 TLB */
80*4882a593Smuzhiyun
81*4882a593Smuzhiyun	/*
82*4882a593Smuzhiyun	 * disable MMU stuff and caches
83*4882a593Smuzhiyun	 */
84*4882a593Smuzhiyun	mrc	p15, 0, r0, c1, c0, 0
85*4882a593Smuzhiyun	bic	r0, r0, #0x00002300	@ clear bits 13, 9:8 (--V- --RS)
86*4882a593Smuzhiyun	bic	r0, r0, #0x00000087	@ clear bits 7, 2:0 (B--- -CAM)
87*4882a593Smuzhiyun	orr	r0, r0, #0x00000002	@ set bit 1 (A) Align
88*4882a593Smuzhiyun	orr	r0, r0, #0x00001000	@ set bit 12 (I) I-Cache
89*4882a593Smuzhiyun
90*4882a593Smuzhiyun	/* Prepare to disable the MMU */
91*4882a593Smuzhiyun	adr	r2, mmu_disable_phys
92*4882a593Smuzhiyun	sub	r2, r2, #(CONFIG_SYS_PHY_UBOOT_BASE - CONFIG_SYS_TEXT_BASE)
93*4882a593Smuzhiyun	b	mmu_disable
94*4882a593Smuzhiyun
95*4882a593Smuzhiyun	.align 5
96*4882a593Smuzhiyun	/* Run in a single cache-line */
97*4882a593Smuzhiyunmmu_disable:
98*4882a593Smuzhiyun	mcr	p15, 0, r0, c1, c0, 0
99*4882a593Smuzhiyun	nop
100*4882a593Smuzhiyun	nop
101*4882a593Smuzhiyun	mov	pc, r2
102*4882a593Smuzhiyunmmu_disable_phys:
103*4882a593Smuzhiyun
104*4882a593Smuzhiyun#endif
105*4882a593Smuzhiyun
106*4882a593Smuzhiyun	/*
107*4882a593Smuzhiyun	 * Go setup Memory and board specific bits prior to relocation.
108*4882a593Smuzhiyun	 */
109*4882a593Smuzhiyun	bl	lowlevel_init		/* go setup pll,mux,memory */
110*4882a593Smuzhiyun
111*4882a593Smuzhiyun	bl	_main
112*4882a593Smuzhiyun
113*4882a593Smuzhiyun/*------------------------------------------------------------------------------*/
114*4882a593Smuzhiyun
115*4882a593Smuzhiyun	.globl	c_runtime_cpu_setup
116*4882a593Smuzhiyunc_runtime_cpu_setup:
117*4882a593Smuzhiyun
118*4882a593Smuzhiyun	mov	pc, lr
119*4882a593Smuzhiyun
120*4882a593SmuzhiyunWEAK(save_boot_params)
121*4882a593Smuzhiyun	b	save_boot_params_ret	/* back to my caller */
122*4882a593SmuzhiyunENDPROC(save_boot_params)
123