xref: /openbmc/u-boot/arch/m68k/cpu/mcf52x2/start.S (revision e77e65df)
1/*
2 * Copyright (C) 2003	Josef Baumgartner <josef.baumgartner@telex.de>
3 * Based on code from Bernhard Kuhn <bkuhn@metrowerks.com>
4 *
5 * SPDX-License-Identifier:	GPL-2.0+
6 */
7
8#include <asm-offsets.h>
9#include <config.h>
10#include "version.h"
11#include <asm/cache.h>
12
13#ifndef	 CONFIG_IDENT_STRING
14#define	 CONFIG_IDENT_STRING ""
15#endif
16
17#define _START	_start
18#define _FAULT	_fault
19
20
21#define SAVE_ALL						\
22	move.w	#0x2700,%sr;		/* disable intrs */	\
23	subl	#60,%sp;		/* space for 15 regs */ \
24	moveml	%d0-%d7/%a0-%a6,%sp@;				\
25
26#define RESTORE_ALL						\
27	moveml	%sp@,%d0-%d7/%a0-%a6;				\
28	addl	#60,%sp;		/* space for 15 regs */ \
29	rte
30
31/* If we come from a pre-loader we don't need an initial exception
32 * table.
33 */
34#if !defined(CONFIG_MONITOR_IS_IN_RAM)
35
36.text
37/*
38 *	Vector table. This is used for initial platform startup.
39 *	These vectors are to catch any un-intended traps.
40 */
41_vectors:
42
43.long	0x00000000		/* Flash offset is 0 until we setup CS0 */
44#if defined(CONFIG_M5282) && (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
45.long	_start - CONFIG_SYS_TEXT_BASE
46#else
47.long	_START
48#endif
49
50.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
51.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
52.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
53.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
54.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
55.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
56.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
57.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
58
59.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
60.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
61.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
62.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
63.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
64.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
65.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
66.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
67
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, _FAULT, _FAULT
75.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
76
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.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
85
86#endif
87
88	.text
89
90
91#if defined(CONFIG_SYS_INT_FLASH_BASE) && \
92    (defined(CONFIG_M5282) || defined(CONFIG_M5281))
93	#if (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
94		.long	0x55AA55AA,0xAA55AA55 /* CFM Backdoorkey */
95		.long	0xFFFFFFFF /* all sectors protected */
96		.long	0x00000000 /* supervisor/User restriction */
97		.long	0x00000000 /* programm/data space restriction */
98		.long	0x00000000 /* Flash security */
99	#endif
100#endif
101	.globl	_start
102_start:
103	nop
104	nop
105	move.w #0x2700,%sr
106
107#if defined(CONFIG_M5208)
108	/* Initialize RAMBAR: locate SRAM and validate it */
109	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_RAM_CTRL), %d0
110	movec	%d0, %RAMBAR1
111#endif
112
113#if defined(CONFIG_M5272) || defined(CONFIG_M5249) || defined(CONFIG_M5253)
114	move.l	#(CONFIG_SYS_MBAR + 1), %d0		/* set MBAR address + valid flag */
115	move.c	%d0, %MBAR
116
117	/*** The 5249 has MBAR2 as well ***/
118#ifdef CONFIG_SYS_MBAR2
119	move.l	#(CONFIG_SYS_MBAR2 + 1), %d0	        /* Get MBAR2 address */
120	movec	%d0, #0xc0e		        /* Set MBAR2 */
121#endif
122
123	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + 1), %d0
124	movec	%d0, %RAMBAR0
125#endif /* CONFIG_M5272 || CONFIG_M5249 || CONFIG_M5253 */
126
127#if defined(CONFIG_M5282) || defined(CONFIG_M5271)
128	/* Initialize IPSBAR */
129	move.l	#(CONFIG_SYS_MBAR + 1), %d0		/* set IPSBAR address + valid flag */
130	move.l	%d0, 0x40000000
131
132	/* Initialize RAMBAR1: locate SRAM and validate it */
133	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + 0x21), %d0
134	movec	%d0, %RAMBAR1
135
136#if defined(CONFIG_M5282)
137#if (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
138	/* Setup code in SRAM to initialize FLASHBAR, if start from internal Flash */
139
140	move.l #(_flashbar_setup-CONFIG_SYS_INT_FLASH_BASE), %a0
141	move.l #(_flashbar_setup_end-CONFIG_SYS_INT_FLASH_BASE), %a1
142	move.l #(CONFIG_SYS_INIT_RAM_ADDR), %a2
143_copy_flash:
144	move.l (%a0)+, (%a2)+
145	cmp.l %a0, %a1
146	bgt.s _copy_flash
147	jmp CONFIG_SYS_INIT_RAM_ADDR
148
149_flashbar_setup:
150	/* Initialize FLASHBAR: locate internal Flash and validate it */
151	move.l	#(CONFIG_SYS_INT_FLASH_BASE + CONFIG_SYS_INT_FLASH_ENABLE), %d0
152	movec	%d0, %FLASHBAR
153	jmp _after_flashbar_copy.L	/* Force jump to absolute address */
154_flashbar_setup_end:
155	nop
156_after_flashbar_copy:
157#else
158	/* Setup code to initialize FLASHBAR, if start from external Memory */
159	move.l	#(CONFIG_SYS_INT_FLASH_BASE + CONFIG_SYS_INT_FLASH_ENABLE), %d0
160	movec	%d0, %FLASHBAR
161#endif /* (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE) */
162
163#endif
164#endif
165	/* if we come from a pre-loader we have no exception table and
166	 * therefore no VBR to set
167	 */
168#if !defined(CONFIG_MONITOR_IS_IN_RAM)
169#if defined(CONFIG_M5282) && (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
170	move.l	#CONFIG_SYS_INT_FLASH_BASE, %d0
171#else
172	move.l	#CONFIG_SYS_FLASH_BASE, %d0
173#endif
174	movec	%d0, %VBR
175#endif
176
177#ifdef CONFIG_M5275
178	/* Initialize IPSBAR */
179	move.l	#(CONFIG_SYS_MBAR + 1), %d0		/* set IPSBAR address + valid flag */
180	move.l	%d0, 0x40000000
181/*	movec	%d0, %MBAR */
182
183	/* Initialize RAMBAR: locate SRAM and validate it */
184	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + 0x21), %d0
185	movec	%d0, %RAMBAR1
186#endif
187
188	/* initialize general use internal ram */
189	move.l #0, %d0
190	move.l #(ICACHE_STATUS), %a1	/* icache */
191	move.l #(DCACHE_STATUS), %a2	/* icache */
192	move.l %d0, (%a1)
193	move.l %d0, (%a2)
194
195	/* set stackpointer to end of internal ram to get some stackspace for the first c-code */
196	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_SP_OFFSET), %sp
197	clr.l %sp@-
198
199	move.l #__got_start, %a5		/* put relocation table address to a5 */
200
201	bsr cpu_init_f				/* run low-level CPU init code (from flash) */
202	bsr board_init_f			/* run low-level board init code (from flash) */
203
204	/* board_init_f() does not return */
205
206/*------------------------------------------------------------------------------*/
207
208/*
209 * void relocate_code (addr_sp, gd, addr_moni)
210 *
211 * This "function" does not return, instead it continues in RAM
212 * after relocating the monitor code.
213 *
214 * r3 = dest
215 * r4 = src
216 * r5 = length in bytes
217 * r6 = cachelinesize
218 */
219	.globl	relocate_code
220relocate_code:
221	link.w %a6,#0
222	move.l 8(%a6), %sp		/* set new stack pointer */
223
224	move.l 12(%a6), %d0		/* Save copy of Global Data pointer */
225	move.l 16(%a6), %a0		/* Save copy of Destination Address */
226
227	move.l #CONFIG_SYS_MONITOR_BASE, %a1
228	move.l #__init_end, %a2
229	move.l %a0, %a3
230	/* copy the code to RAM */
2311:
232	move.l (%a1)+, (%a3)+
233	cmp.l  %a1,%a2
234	bgt.s	 1b
235
236/*
237 * We are done. Do not return, instead branch to second part of board
238 * initialization, now running from RAM.
239 */
240	move.l	%a0, %a1
241	add.l	#(in_ram - CONFIG_SYS_MONITOR_BASE), %a1
242	jmp	(%a1)
243
244in_ram:
245
246clear_bss:
247	/*
248	 * Now clear BSS segment
249	 */
250	move.l	%a0, %a1
251	add.l	#(_sbss - CONFIG_SYS_MONITOR_BASE),%a1
252	move.l	%a0, %d1
253	add.l	#(_ebss - CONFIG_SYS_MONITOR_BASE),%d1
2546:
255	clr.l	(%a1)+
256	cmp.l	%a1,%d1
257	bgt.s	6b
258
259	/*
260	 * fix got table in RAM
261	 */
262	move.l	%a0, %a1
263	add.l	#(__got_start - CONFIG_SYS_MONITOR_BASE),%a1
264	move.l	%a1,%a5		/* * fix got pointer register a5 */
265
266	move.l	%a0, %a2
267	add.l	#(__got_end - CONFIG_SYS_MONITOR_BASE),%a2
268
2697:
270	move.l	(%a1),%d1
271	sub.l	#_start,%d1
272	add.l	%a0,%d1
273	move.l	%d1,(%a1)+
274	cmp.l	%a2, %a1
275	bne	7b
276
277	/* calculate relative jump to board_init_r in ram */
278	move.l %a0, %a1
279	add.l #(board_init_r - CONFIG_SYS_MONITOR_BASE), %a1
280
281	/* set parameters for board_init_r */
282	move.l %a0,-(%sp)		/* dest_addr */
283	move.l %d0,-(%sp)		/* gd */
284#if defined(DEBUG) && (CONFIG_SYS_TEXT_BASE != CONFIG_SYS_INT_FLASH_BASE) && \
285    defined(CONFIG_SYS_HALT_BEFOR_RAM_JUMP)
286	halt
287#endif
288	jsr	(%a1)
289
290/*------------------------------------------------------------------------------*/
291/* exception code */
292	.globl _fault
293_fault:
294	bra _fault
295
296	.globl	_exc_handler
297_exc_handler:
298	SAVE_ALL
299	movel	%sp,%sp@-
300	bsr exc_handler
301	addql	#4,%sp
302	RESTORE_ALL
303
304	.globl	_int_handler
305_int_handler:
306	SAVE_ALL
307	movel	%sp,%sp@-
308	bsr int_handler
309	addql	#4,%sp
310	RESTORE_ALL
311
312/*------------------------------------------------------------------------------*/
313
314	.globl	version_string
315version_string:
316	.ascii U_BOOT_VERSION_STRING, "\0"
317	.align 4
318