xref: /openbmc/u-boot/arch/m68k/cpu/mcf523x/start.S (revision c6af2e7d)
1/*
2 * Copyright (C) 2003	Josef Baumgartner <josef.baumgartner@telex.de>
3 * Based on code from Bernhard Kuhn <bkuhn@metrowerks.com>
4 *
5 * See file CREDITS for list of people who contributed to this
6 * project.
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of
11 * the License, or (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21 * MA 02111-1307 USA
22 */
23
24#include <asm-offsets.h>
25#include <config.h>
26#include "version.h"
27#include <asm/cache.h>
28
29#ifndef	 CONFIG_IDENT_STRING
30#define	 CONFIG_IDENT_STRING ""
31#endif
32
33#define _START	_start
34#define _FAULT	_fault
35
36#define SAVE_ALL						\
37	move.w	#0x2700,%sr;		/* disable intrs */	\
38	subl	#60,%sp;		/* space for 15 regs */ \
39	moveml	%d0-%d7/%a0-%a6,%sp@;
40
41#define RESTORE_ALL						\
42	moveml	%sp@,%d0-%d7/%a0-%a6;				\
43	addl	#60,%sp;		/* space for 15 regs */ \
44	rte;
45
46.text
47/*
48 *	Vector table. This is used for initial platform startup.
49 *	These vectors are to catch any un-intended traps.
50 */
51_vectors:
52
53INITSP:		.long	0x00000000	/* Initial SP	*/
54INITPC:		.long	_START	/* Initial PC		*/
55vector02:	.long	_FAULT	/* Access Error		*/
56vector03:	.long	_FAULT	/* Address Error	*/
57vector04:	.long	_FAULT	/* Illegal Instruction	*/
58vector05:	.long	_FAULT	/* Reserved		*/
59vector06:	.long	_FAULT	/* Reserved		*/
60vector07:	.long	_FAULT	/* Reserved		*/
61vector08:	.long	_FAULT	/* Privilege Violation	*/
62vector09:	.long	_FAULT	/* Trace		*/
63vector0A:	.long	_FAULT	/* Unimplemented A-Line	*/
64vector0B:	.long	_FAULT	/* Unimplemented F-Line	*/
65vector0C:	.long	_FAULT	/* Debug Interrupt	*/
66vector0D:	.long	_FAULT	/* Reserved		*/
67vector0E:	.long	_FAULT	/* Format Error		*/
68vector0F:	.long	_FAULT	/* Unitialized Int.	*/
69
70/* Reserved */
71vector10_17:
72.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
73
74vector18:	.long	_FAULT	/* Spurious Interrupt	*/
75vector19:	.long	_FAULT	/* Autovector Level 1	*/
76vector1A:	.long	_FAULT	/* Autovector Level 2	*/
77vector1B:	.long	_FAULT	/* Autovector Level 3	*/
78vector1C:	.long	_FAULT	/* Autovector Level 4	*/
79vector1D:	.long	_FAULT	/* Autovector Level 5	*/
80vector1E:	.long	_FAULT	/* Autovector Level 6	*/
81vector1F:	.long	_FAULT	/* Autovector Level 7	*/
82
83/* TRAP #0 - #15 */
84vector20_2F:
85.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
86.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
87
88/* Reserved	*/
89vector30_3F:
90.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
91.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
92
93vector64_127:
94.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
95.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
96.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
97.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
98.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
99.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
100.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
101.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
102
103vector128_191:
104.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
105.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
106.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
107.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
108.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
109.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
110.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
111.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
112
113vector192_255:
114.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
115.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
116.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
117.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
118.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
119.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
120.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
121.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
122
123	.text
124
125	.globl	_start
126_start:
127	nop
128	nop
129	move.w #0x2700,%sr	/* Mask off Interrupt */
130
131	/* Set vector base register at the beginning of the Flash */
132	move.l	#CONFIG_SYS_FLASH_BASE, %d0
133	movec	%d0, %VBR
134
135	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_RAM_CTRL), %d0
136	movec	%d0, %RAMBAR1
137
138	/* invalidate and disable cache */
139	move.l	#CF_CACR_CINV, %d0		/* Invalidate cache cmd */
140	movec	%d0, %CACR			/* Invalidate cache */
141	nop
142	move.l	#0, %d0
143	movec	%d0, %ACR0
144	movec	%d0, %ACR1
145
146	/* initialize general use internal ram */
147	move.l #0, %d0
148	move.l #(ICACHE_STATUS), %a1	/* icache */
149	move.l #(DCACHE_STATUS), %a2	/* icache */
150	move.l %d0, (%a1)
151	move.l %d0, (%a2)
152
153	/* set stackpointer to end of internal ram to get some stackspace for the
154	   first c-code */
155	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_SP_OFFSET), %sp
156	clr.l %sp@-
157
158	move.l #__got_start, %a5	/* put relocation table address to a5 */
159
160	bsr cpu_init_f			/* run low-level CPU init code (from flash) */
161	bsr board_init_f		/* run low-level board init code (from flash) */
162
163	/* board_init_f() does not return */
164
165/*------------------------------------------------------------------------------*/
166
167/*
168 * void relocate_code (addr_sp, gd, addr_moni)
169 *
170 * This "function" does not return, instead it continues in RAM
171 * after relocating the monitor code.
172 *
173 * r3 = dest
174 * r4 = src
175 * r5 = length in bytes
176 * r6 = cachelinesize
177 */
178	.globl	relocate_code
179relocate_code:
180	link.w %a6,#0
181	move.l 8(%a6), %sp		/* set new stack pointer */
182
183	move.l 12(%a6), %d0		/* Save copy of Global Data pointer */
184	move.l 16(%a6), %a0		/* Save copy of Destination Address */
185
186	move.l #CONFIG_SYS_MONITOR_BASE, %a1
187	move.l #__init_end, %a2
188	move.l %a0, %a3
189
190	/* copy the code to RAM */
1911:
192	move.l (%a1)+, (%a3)+
193	cmp.l  %a1,%a2
194	bgt.s	 1b
195
196/*
197 * We are done. Do not return, instead branch to second part of board
198 * initialization, now running from RAM.
199 */
200	move.l	%a0, %a1
201	add.l	#(in_ram - CONFIG_SYS_MONITOR_BASE), %a1
202	jmp	(%a1)
203
204in_ram:
205
206clear_bss:
207	/*
208	 * Now clear BSS segment
209	 */
210	move.l	%a0, %a1
211	add.l	#(_sbss - CONFIG_SYS_MONITOR_BASE),%a1
212	move.l	%a0, %d1
213	add.l	#(_ebss - CONFIG_SYS_MONITOR_BASE),%d1
2146:
215	clr.l	(%a1)+
216	cmp.l	%a1,%d1
217	bgt.s	6b
218
219	/*
220	 * fix got table in RAM
221	 */
222	move.l	%a0, %a1
223	add.l	#(__got_start - CONFIG_SYS_MONITOR_BASE),%a1
224	move.l	%a1,%a5		/* * fix got pointer register a5 */
225
226	move.l	%a0, %a2
227	add.l	#(__got_end - CONFIG_SYS_MONITOR_BASE),%a2
228
2297:
230	move.l	(%a1),%d1
231	sub.l	#_start,%d1
232	add.l	%a0,%d1
233	move.l	%d1,(%a1)+
234	cmp.l	%a2, %a1
235	bne	7b
236
237	/* calculate relative jump to board_init_r in ram */
238	move.l %a0, %a1
239	add.l #(board_init_r - CONFIG_SYS_MONITOR_BASE), %a1
240
241	/* set parameters for board_init_r */
242	move.l %a0,-(%sp)		/* dest_addr */
243	move.l %d0,-(%sp)		/* gd */
244	jsr	(%a1)
245
246/*------------------------------------------------------------------------------*/
247/* exception code */
248	.globl _fault
249_fault:
250	jmp _fault
251	.globl	_exc_handler
252
253_exc_handler:
254	SAVE_ALL
255	movel	%sp,%sp@-
256	bsr exc_handler
257	addql	#4,%sp
258	RESTORE_ALL
259
260	.globl	_int_handler
261_int_handler:
262	SAVE_ALL
263	movel	%sp,%sp@-
264	bsr int_handler
265	addql	#4,%sp
266	RESTORE_ALL
267
268/*------------------------------------------------------------------------------*/
269
270	.globl	version_string
271version_string:
272	.ascii U_BOOT_VERSION_STRING, "\0"
273	.align 4
274