1/*	$NetBSD: smdk2800_start.S,v 1.1 2002/11/20 18:06:26 bsh Exp $ */
2
3/*
4 * Copyright (c) 2002 Fujitsu Component Limited
5 * Copyright (c) 2002 Genetec Corporation
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of The Fujitsu Component Limited nor the name of
17 *    Genetec corporation may not be used to endorse or promote products
18 *    derived from this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY FUJITSU COMPONENT LIMITED AND GENETEC
21 * CORPORATION ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
22 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
23 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
24 * DISCLAIMED.  IN NO EVENT SHALL FUJITSU COMPONENT LIMITED OR GENETEC
25 * CORPORATION BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
28 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
29 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#include <machine/asm.h>
36#include <arm/armreg.h>
37#include <arm/arm32/pte.h>
38
39/*
40 * Kernel start routine for Samsung SMDK2800.
41 * This code is excuted at the very first after the kernel is loaded
42 * by boot program on ROM or gzboot.
43 */
44	.text
45
46	.global	_C_LABEL(smdk2800_start)
47_C_LABEL(smdk2800_start):
48	/* Are we running on ROM ? */
49	cmp	pc, #0x08200000
50	bhs	smdk2800_start_ram
51
52	/* move me to RAM
53	 * XXX: we can use memcpy if it is PIC
54	 */
55	ldr r1, Lcopy_size
56	adr r0, _C_LABEL(smdk2800_start)
57	add r1, r1, #3
58	mov r1, r1, LSR #2
59	mov r2, #0x08200000
60	mov r4, r2
61
62	cmp r0, r2
63	bhs 5f
64
65	/* src < dest. copy from top */
66	add r0,r0,r1,LSL #2
67	add r2,r2,r1,LSL #2
68
693:	ldr r3,[r0,#-4]!
70	str r3,[r2,#-4]!
71	subs r1,r1,#1
72	bhi 3b
73	b 7f
74
75	/* src >= dest. copy from bottom */
765:	ldr r3,[r0],#4
77	str r3,[r2],#4
78	subs r1,r1,#1
79	bhi 5b
80
817:
82	/* Jump to RAM */
83	ldr r0, Lstart_off
84	add pc, r4, r0
85
86Lcopy_size:	.word _edata-_C_LABEL(smdk2800_start)
87Lstart_off:	.word smdk2800_start_ram-_C_LABEL(smdk2800_start)
88
89smdk2800_start_ram:
90	/*
91	 *  Kernel is loaded in SDRAM (0x08200000..), and is expected to run
92	 *  in VA 0xc0200000..
93	 */
94
95	/* get ttb prepared by boot program */
96	mrc p15, 0, r0, c2, c0, 0
97	/* Disable MMU for a while */
98	mrc	p15, 0, r2, c1, c0, 0
99	bic	r2, r2, #CPU_CONTROL_MMU_ENABLE
100	mcr	p15, 0, r2, c1, c0, 0
101
102	nop
103	nop
104	nop
105
106	/*
107	 * Map VA 0xc0000000..0xc3ffffff to PA 0x08000000..0x09ffffff
108	 */
109	mov	r1, #(L1_S_AP(AP_KRW))
110	orr	r1, r1, #(L1_TYPE_S)
111	orr	r1, r1, #0x08000000
112	mov	r2, #(0xc00 * 4)
1131:
114	str	r1, [r0, r2]
115	add	r2, r2, #4
116	add	r1, r1, #L1_S_SIZE
117	cmp	r2, #(0xc20 * 4)
118	blo	1b
119
120
121	mcr	p15, 0, r0, c2, c0, 0	/* Set TTB */
122	mcr	p15, 0, r0, c8, c7, 0	/* Flush TLB */
123
124	/* Set the Domain Access register.  Very important! */
125	mov	r0, #1
126	mcr	p15, 0, r0, c3, c0, 0
127
128	/* Enable MMU */
129	mrc	p15, 0, r0, c1, c0, 0
130	orr	r0, r0, #CPU_CONTROL_MMU_ENABLE
131	mcr	p15, 0, r0, c1, c0, 0
132
133	nop
134	nop
135	nop
136
137	/* Jump to kernel code in TRUE VA */
138	adr	r0, Lstart
139	ldr	pc, [r0]
140
141Lstart:
142	.word	start
143