xref: /openbmc/u-boot/arch/m68k/cpu/mcf52x2/start.S (revision fea25720)
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 <timestamp.h>
27#include "version.h"
28#include <asm/cache.h>
29
30#ifndef	 CONFIG_IDENT_STRING
31#define	 CONFIG_IDENT_STRING ""
32#endif
33
34#define _START	_start
35#define _FAULT	_fault
36
37
38#define SAVE_ALL						\
39	move.w	#0x2700,%sr;		/* disable intrs */	\
40	subl	#60,%sp;		/* space for 15 regs */ \
41	moveml	%d0-%d7/%a0-%a6,%sp@;				\
42
43#define RESTORE_ALL						\
44	moveml	%sp@,%d0-%d7/%a0-%a6;				\
45	addl	#60,%sp;		/* space for 15 regs */ \
46	rte
47
48/* If we come from a pre-loader we don't need an initial exception
49 * table.
50 */
51#if !defined(CONFIG_MONITOR_IS_IN_RAM)
52
53.text
54/*
55 *	Vector table. This is used for initial platform startup.
56 *	These vectors are to catch any un-intended traps.
57 */
58_vectors:
59
60.long	0x00000000		/* Flash offset is 0 until we setup CS0 */
61#if defined(CONFIG_M5282) && (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
62.long	_start - CONFIG_SYS_TEXT_BASE
63#else
64.long	_START
65#endif
66
67.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
68.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
69.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
70.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
71.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
72.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
73.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
74.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
75
76.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
77.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
78.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
79.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
80.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
81.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
82.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
83.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
84
85.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
86.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
87.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
88.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
89.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
90.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
91.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
92.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
93
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
103#endif
104
105	.text
106
107
108#if defined(CONFIG_SYS_INT_FLASH_BASE) && \
109    (defined(CONFIG_M5282) || defined(CONFIG_M5281))
110	#if (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
111		.long	0x55AA55AA,0xAA55AA55 /* CFM Backdoorkey */
112		.long	0xFFFFFFFF /* all sectors protected */
113		.long	0x00000000 /* supervisor/User restriction */
114		.long	0x00000000 /* programm/data space restriction */
115		.long	0x00000000 /* Flash security */
116	#endif
117#endif
118	.globl	_start
119_start:
120	nop
121	nop
122	move.w #0x2700,%sr
123
124#if defined(CONFIG_M5208)
125	/* Initialize RAMBAR: locate SRAM and validate it */
126	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_RAM_CTRL), %d0
127	movec	%d0, %RAMBAR1
128#endif
129
130#if defined(CONFIG_M5272) || defined(CONFIG_M5249) || defined(CONFIG_M5253)
131	move.l	#(CONFIG_SYS_MBAR + 1), %d0		/* set MBAR address + valid flag */
132	move.c	%d0, %MBAR
133
134	/*** The 5249 has MBAR2 as well ***/
135#ifdef CONFIG_SYS_MBAR2
136	move.l	#(CONFIG_SYS_MBAR2 + 1), %d0	        /* Get MBAR2 address */
137	movec	%d0, #0xc0e		        /* Set MBAR2 */
138#endif
139
140	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + 1), %d0
141	movec	%d0, %RAMBAR0
142#endif /* CONFIG_M5272 || CONFIG_M5249 || CONFIG_M5253 */
143
144#if defined(CONFIG_M5282) || defined(CONFIG_M5271)
145	/* Initialize IPSBAR */
146	move.l	#(CONFIG_SYS_MBAR + 1), %d0		/* set IPSBAR address + valid flag */
147	move.l	%d0, 0x40000000
148
149	/* Initialize RAMBAR1: locate SRAM and validate it */
150	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + 0x21), %d0
151	movec	%d0, %RAMBAR1
152
153#if defined(CONFIG_M5282)
154#if (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
155	/* Setup code in SRAM to initialize FLASHBAR, if start from internal Flash */
156
157	move.l #(_flashbar_setup-CONFIG_SYS_INT_FLASH_BASE), %a0
158	move.l #(_flashbar_setup_end-CONFIG_SYS_INT_FLASH_BASE), %a1
159	move.l #(CONFIG_SYS_INIT_RAM_ADDR), %a2
160_copy_flash:
161	move.l (%a0)+, (%a2)+
162	cmp.l %a0, %a1
163	bgt.s _copy_flash
164	jmp CONFIG_SYS_INIT_RAM_ADDR
165
166_flashbar_setup:
167	/* Initialize FLASHBAR: locate internal Flash and validate it */
168	move.l	#(CONFIG_SYS_INT_FLASH_BASE + CONFIG_SYS_INT_FLASH_ENABLE), %d0
169	movec	%d0, %FLASHBAR
170	jmp _after_flashbar_copy.L	/* Force jump to absolute address */
171_flashbar_setup_end:
172	nop
173_after_flashbar_copy:
174#else
175	/* Setup code to initialize FLASHBAR, if start from external Memory */
176	move.l	#(CONFIG_SYS_INT_FLASH_BASE + CONFIG_SYS_INT_FLASH_ENABLE), %d0
177	movec	%d0, %FLASHBAR
178#endif /* (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE) */
179
180#endif
181#endif
182	/* if we come from a pre-loader we have no exception table and
183	 * therefore no VBR to set
184	 */
185#if !defined(CONFIG_MONITOR_IS_IN_RAM)
186#if defined(CONFIG_M5282) && (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
187	move.l	#CONFIG_SYS_INT_FLASH_BASE, %d0
188#else
189	move.l	#CONFIG_SYS_FLASH_BASE, %d0
190#endif
191	movec	%d0, %VBR
192#endif
193
194#ifdef CONFIG_M5275
195	/* Initialize IPSBAR */
196	move.l	#(CONFIG_SYS_MBAR + 1), %d0		/* set IPSBAR address + valid flag */
197	move.l	%d0, 0x40000000
198/*	movec	%d0, %MBAR */
199
200	/* Initialize RAMBAR: locate SRAM and validate it */
201	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + 0x21), %d0
202	movec	%d0, %RAMBAR1
203#endif
204
205	/* initialize general use internal ram */
206	move.l #0, %d0
207	move.l #(ICACHE_STATUS), %a1	/* icache */
208	move.l #(DCACHE_STATUS), %a2	/* icache */
209	move.l %d0, (%a1)
210	move.l %d0, (%a2)
211
212	/* set stackpointer to end of internal ram to get some stackspace for the first c-code */
213	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_SP_OFFSET), %sp
214	clr.l %sp@-
215
216	move.l #__got_start, %a5		/* put relocation table address to a5 */
217
218	bsr cpu_init_f				/* run low-level CPU init code (from flash) */
219	bsr board_init_f			/* run low-level board init code (from flash) */
220
221	/* board_init_f() does not return */
222
223/*------------------------------------------------------------------------------*/
224
225/*
226 * void relocate_code (addr_sp, gd, addr_moni)
227 *
228 * This "function" does not return, instead it continues in RAM
229 * after relocating the monitor code.
230 *
231 * r3 = dest
232 * r4 = src
233 * r5 = length in bytes
234 * r6 = cachelinesize
235 */
236	.globl	relocate_code
237relocate_code:
238	link.w %a6,#0
239	move.l 8(%a6), %sp		/* set new stack pointer */
240
241	move.l 12(%a6), %d0		/* Save copy of Global Data pointer */
242	move.l 16(%a6), %a0		/* Save copy of Destination Address */
243
244	move.l #CONFIG_SYS_MONITOR_BASE, %a1
245	move.l #__init_end, %a2
246	move.l %a0, %a3
247	/* copy the code to RAM */
2481:
249	move.l (%a1)+, (%a3)+
250	cmp.l  %a1,%a2
251	bgt.s	 1b
252
253/*
254 * We are done. Do not return, instead branch to second part of board
255 * initialization, now running from RAM.
256 */
257	move.l	%a0, %a1
258	add.l	#(in_ram - CONFIG_SYS_MONITOR_BASE), %a1
259	jmp	(%a1)
260
261in_ram:
262
263clear_bss:
264	/*
265	 * Now clear BSS segment
266	 */
267	move.l	%a0, %a1
268	add.l	#(_sbss - CONFIG_SYS_MONITOR_BASE),%a1
269	move.l	%a0, %d1
270	add.l	#(_ebss - CONFIG_SYS_MONITOR_BASE),%d1
2716:
272	clr.l	(%a1)+
273	cmp.l	%a1,%d1
274	bgt.s	6b
275
276	/*
277	 * fix got table in RAM
278	 */
279	move.l	%a0, %a1
280	add.l	#(__got_start - CONFIG_SYS_MONITOR_BASE),%a1
281	move.l	%a1,%a5		/* * fix got pointer register a5 */
282
283	move.l	%a0, %a2
284	add.l	#(__got_end - CONFIG_SYS_MONITOR_BASE),%a2
285
2867:
287	move.l	(%a1),%d1
288	sub.l	#_start,%d1
289	add.l	%a0,%d1
290	move.l	%d1,(%a1)+
291	cmp.l	%a2, %a1
292	bne	7b
293
294	/* calculate relative jump to board_init_r in ram */
295	move.l %a0, %a1
296	add.l #(board_init_r - CONFIG_SYS_MONITOR_BASE), %a1
297
298	/* set parameters for board_init_r */
299	move.l %a0,-(%sp)		/* dest_addr */
300	move.l %d0,-(%sp)		/* gd */
301#if defined(DEBUG) && (CONFIG_SYS_TEXT_BASE != CONFIG_SYS_INT_FLASH_BASE) && \
302    defined(CONFIG_SYS_HALT_BEFOR_RAM_JUMP)
303	halt
304#endif
305	jsr	(%a1)
306
307/*------------------------------------------------------------------------------*/
308/* exception code */
309	.globl _fault
310_fault:
311	jmp _fault
312
313	.globl	_exc_handler
314_exc_handler:
315	SAVE_ALL
316	movel	%sp,%sp@-
317	bsr exc_handler
318	addql	#4,%sp
319	RESTORE_ALL
320
321	.globl	_int_handler
322_int_handler:
323	SAVE_ALL
324	movel	%sp,%sp@-
325	bsr int_handler
326	addql	#4,%sp
327	RESTORE_ALL
328
329/*------------------------------------------------------------------------------*/
330
331	.globl	version_string
332version_string:
333	.ascii U_BOOT_VERSION
334	.ascii " (", U_BOOT_DATE, " - ", U_BOOT_TIME, ")"
335	.ascii CONFIG_IDENT_STRING, "\0"
336	.align 4
337