xref: /openbmc/u-boot/arch/m68k/cpu/mcf52x2/start.S (revision 10980d4a)
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
37#define SAVE_ALL						\
38	move.w	#0x2700,%sr;		/* disable intrs */	\
39	subl	#60,%sp;		/* space for 15 regs */ \
40	moveml	%d0-%d7/%a0-%a6,%sp@;				\
41
42#define RESTORE_ALL						\
43	moveml	%sp@,%d0-%d7/%a0-%a6;				\
44	addl	#60,%sp;		/* space for 15 regs */ \
45	rte
46
47/* If we come from a pre-loader we don't need an initial exception
48 * table.
49 */
50#if !defined(CONFIG_MONITOR_IS_IN_RAM)
51
52.text
53/*
54 *	Vector table. This is used for initial platform startup.
55 *	These vectors are to catch any un-intended traps.
56 */
57_vectors:
58
59.long	0x00000000		/* Flash offset is 0 until we setup CS0 */
60#if defined(CONFIG_M5282) && (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
61.long	_start - CONFIG_SYS_TEXT_BASE
62#else
63.long	_START
64#endif
65
66.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
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
74
75.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
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
84.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
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
93.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
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
102#endif
103
104	.text
105
106
107#if defined(CONFIG_SYS_INT_FLASH_BASE) && \
108    (defined(CONFIG_M5282) || defined(CONFIG_M5281))
109	#if (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
110		.long	0x55AA55AA,0xAA55AA55 /* CFM Backdoorkey */
111		.long	0xFFFFFFFF /* all sectors protected */
112		.long	0x00000000 /* supervisor/User restriction */
113		.long	0x00000000 /* programm/data space restriction */
114		.long	0x00000000 /* Flash security */
115	#endif
116#endif
117	.globl	_start
118_start:
119	nop
120	nop
121	move.w #0x2700,%sr
122
123#if defined(CONFIG_M5208)
124	/* Initialize RAMBAR: locate SRAM and validate it */
125	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_RAM_CTRL), %d0
126	movec	%d0, %RAMBAR1
127#endif
128
129#if defined(CONFIG_M5272) || defined(CONFIG_M5249) || defined(CONFIG_M5253)
130	move.l	#(CONFIG_SYS_MBAR + 1), %d0		/* set MBAR address + valid flag */
131	move.c	%d0, %MBAR
132
133	/*** The 5249 has MBAR2 as well ***/
134#ifdef CONFIG_SYS_MBAR2
135	move.l	#(CONFIG_SYS_MBAR2 + 1), %d0	        /* Get MBAR2 address */
136	movec	%d0, #0xc0e		        /* Set MBAR2 */
137#endif
138
139	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + 1), %d0
140	movec	%d0, %RAMBAR0
141#endif /* CONFIG_M5272 || CONFIG_M5249 || CONFIG_M5253 */
142
143#if defined(CONFIG_M5282) || defined(CONFIG_M5271)
144	/* Initialize IPSBAR */
145	move.l	#(CONFIG_SYS_MBAR + 1), %d0		/* set IPSBAR address + valid flag */
146	move.l	%d0, 0x40000000
147
148	/* Initialize RAMBAR1: locate SRAM and validate it */
149	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + 0x21), %d0
150	movec	%d0, %RAMBAR1
151
152#if defined(CONFIG_M5282)
153#if (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
154	/* Setup code in SRAM to initialize FLASHBAR, if start from internal Flash */
155
156	move.l #(_flashbar_setup-CONFIG_SYS_INT_FLASH_BASE), %a0
157	move.l #(_flashbar_setup_end-CONFIG_SYS_INT_FLASH_BASE), %a1
158	move.l #(CONFIG_SYS_INIT_RAM_ADDR), %a2
159_copy_flash:
160	move.l (%a0)+, (%a2)+
161	cmp.l %a0, %a1
162	bgt.s _copy_flash
163	jmp CONFIG_SYS_INIT_RAM_ADDR
164
165_flashbar_setup:
166	/* Initialize FLASHBAR: locate internal Flash and validate it */
167	move.l	#(CONFIG_SYS_INT_FLASH_BASE + CONFIG_SYS_INT_FLASH_ENABLE), %d0
168	movec	%d0, %FLASHBAR
169	jmp _after_flashbar_copy.L	/* Force jump to absolute address */
170_flashbar_setup_end:
171	nop
172_after_flashbar_copy:
173#else
174	/* Setup code to initialize FLASHBAR, if start from external Memory */
175	move.l	#(CONFIG_SYS_INT_FLASH_BASE + CONFIG_SYS_INT_FLASH_ENABLE), %d0
176	movec	%d0, %FLASHBAR
177#endif /* (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE) */
178
179#endif
180#endif
181	/* if we come from a pre-loader we have no exception table and
182	 * therefore no VBR to set
183	 */
184#if !defined(CONFIG_MONITOR_IS_IN_RAM)
185#if defined(CONFIG_M5282) && (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
186	move.l	#CONFIG_SYS_INT_FLASH_BASE, %d0
187#else
188	move.l	#CONFIG_SYS_FLASH_BASE, %d0
189#endif
190	movec	%d0, %VBR
191#endif
192
193#ifdef CONFIG_M5275
194	/* Initialize IPSBAR */
195	move.l	#(CONFIG_SYS_MBAR + 1), %d0		/* set IPSBAR address + valid flag */
196	move.l	%d0, 0x40000000
197/*	movec	%d0, %MBAR */
198
199	/* Initialize RAMBAR: locate SRAM and validate it */
200	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + 0x21), %d0
201	movec	%d0, %RAMBAR1
202#endif
203
204	/* initialize general use internal ram */
205	move.l #0, %d0
206	move.l #(ICACHE_STATUS), %a1	/* icache */
207	move.l #(DCACHE_STATUS), %a2	/* icache */
208	move.l %d0, (%a1)
209	move.l %d0, (%a2)
210
211	/* set stackpointer to end of internal ram to get some stackspace for the first c-code */
212	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_SP_OFFSET), %sp
213	clr.l %sp@-
214
215	move.l #__got_start, %a5		/* put relocation table address to a5 */
216
217	bsr cpu_init_f				/* run low-level CPU init code (from flash) */
218	bsr board_init_f			/* run low-level board init code (from flash) */
219
220	/* board_init_f() does not return */
221
222/*------------------------------------------------------------------------------*/
223
224/*
225 * void relocate_code (addr_sp, gd, addr_moni)
226 *
227 * This "function" does not return, instead it continues in RAM
228 * after relocating the monitor code.
229 *
230 * r3 = dest
231 * r4 = src
232 * r5 = length in bytes
233 * r6 = cachelinesize
234 */
235	.globl	relocate_code
236relocate_code:
237	link.w %a6,#0
238	move.l 8(%a6), %sp		/* set new stack pointer */
239
240	move.l 12(%a6), %d0		/* Save copy of Global Data pointer */
241	move.l 16(%a6), %a0		/* Save copy of Destination Address */
242
243	move.l #CONFIG_SYS_MONITOR_BASE, %a1
244	move.l #__init_end, %a2
245	move.l %a0, %a3
246	/* copy the code to RAM */
2471:
248	move.l (%a1)+, (%a3)+
249	cmp.l  %a1,%a2
250	bgt.s	 1b
251
252/*
253 * We are done. Do not return, instead branch to second part of board
254 * initialization, now running from RAM.
255 */
256	move.l	%a0, %a1
257	add.l	#(in_ram - CONFIG_SYS_MONITOR_BASE), %a1
258	jmp	(%a1)
259
260in_ram:
261
262clear_bss:
263	/*
264	 * Now clear BSS segment
265	 */
266	move.l	%a0, %a1
267	add.l	#(_sbss - CONFIG_SYS_MONITOR_BASE),%a1
268	move.l	%a0, %d1
269	add.l	#(_ebss - CONFIG_SYS_MONITOR_BASE),%d1
2706:
271	clr.l	(%a1)+
272	cmp.l	%a1,%d1
273	bgt.s	6b
274
275	/*
276	 * fix got table in RAM
277	 */
278	move.l	%a0, %a1
279	add.l	#(__got_start - CONFIG_SYS_MONITOR_BASE),%a1
280	move.l	%a1,%a5		/* * fix got pointer register a5 */
281
282	move.l	%a0, %a2
283	add.l	#(__got_end - CONFIG_SYS_MONITOR_BASE),%a2
284
2857:
286	move.l	(%a1),%d1
287	sub.l	#_start,%d1
288	add.l	%a0,%d1
289	move.l	%d1,(%a1)+
290	cmp.l	%a2, %a1
291	bne	7b
292
293	/* calculate relative jump to board_init_r in ram */
294	move.l %a0, %a1
295	add.l #(board_init_r - CONFIG_SYS_MONITOR_BASE), %a1
296
297	/* set parameters for board_init_r */
298	move.l %a0,-(%sp)		/* dest_addr */
299	move.l %d0,-(%sp)		/* gd */
300#if defined(DEBUG) && (CONFIG_SYS_TEXT_BASE != CONFIG_SYS_INT_FLASH_BASE) && \
301    defined(CONFIG_SYS_HALT_BEFOR_RAM_JUMP)
302	halt
303#endif
304	jsr	(%a1)
305
306/*------------------------------------------------------------------------------*/
307/* exception code */
308	.globl _fault
309_fault:
310	jmp _fault
311
312	.globl	_exc_handler
313_exc_handler:
314	SAVE_ALL
315	movel	%sp,%sp@-
316	bsr exc_handler
317	addql	#4,%sp
318	RESTORE_ALL
319
320	.globl	_int_handler
321_int_handler:
322	SAVE_ALL
323	movel	%sp,%sp@-
324	bsr int_handler
325	addql	#4,%sp
326	RESTORE_ALL
327
328/*------------------------------------------------------------------------------*/
329
330	.globl	version_string
331version_string:
332	.ascii U_BOOT_VERSION_STRING, "\0"
333	.align 4
334