xref: /openbmc/u-boot/arch/m68k/cpu/mcf530x/start.S (revision c98b171e)
1/*
2 * (C) Copyright 2015  Angelo Dureghello <angelo@sysam.it>
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.macro  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.endm
26
27.macro  RESTORE_ALL
28	moveml	%sp@,%d0-%d7/%a0-%a6;
29	addl	#60,%sp;		/* space for 15 regs */
30	rte
31.endm
32
33/* If we come from a pre-loader we don't need an initial exception
34 * table.
35 */
36#if !defined(CONFIG_MONITOR_IS_IN_RAM)
37
38.text
39
40/*
41 * Vector table. This is used for initial platform startup.
42 * These vectors are to catch any un-intended traps.
43 */
44_vectors:
45/* Flash offset is 0 until we setup CS0 */
46.long	0x00000000
47#if defined(CONFIG_M5307) && \
48	   (CONFIG_SYS_TEXT_BASE == CONFIG_SYS_INT_FLASH_BASE)
49.long	_start - CONFIG_SYS_TEXT_BASE
50#else
51.long	_START
52#endif
53
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, _FAULT, _FAULT
58.long	_FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT, _FAULT
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
62
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.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
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.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
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.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
90#endif
91
92.text
93
94.globl _start
95_start:
96	nop
97	nop
98	move.w	#0x2700,%sr
99
100	/* set MBAR address + valid flag */
101	move.l	#(CONFIG_SYS_MBAR + 1), %d0
102	move.c	%d0, %MBAR
103
104	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + 1), %d0
105	move.c	%d0, %RAMBAR
106
107	/* DS 4.8.2 (Cache Organization) invalidate and disable cache */
108        move.l	#CF_CACR_CINVA, %d0
109        movec	%d0, %CACR
110        move.l	#0, %d0
111        movec	%d0, %ACR0
112        movec	%d0, %ACR1
113
114	/*
115	 * if we come from a pre-loader we have no exception table and
116	 * therefore no VBR to set
117	 */
118#if !defined(CONFIG_MONITOR_IS_IN_RAM)
119	move.l	#CONFIG_SYS_FLASH_BASE, %d0
120	movec	%d0, %VBR
121#endif
122
123	/* initialize general use internal ram */
124	move.l	#0, %d0
125	move.l	#(ICACHE_STATUS), %a1	/* icache */
126	move.l	#(DCACHE_STATUS), %a2	/* dcache */
127	move.l	%d0, (%a1)
128	move.l	%d0, (%a2)
129
130	/* put relocation table address to a5 */
131	move.l	#__got_start, %a5
132
133	/* setup stack initially on top of internal static ram  */
134	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_RAM_SIZE), %sp
135
136	/*
137	 * if configured, malloc_f arena will be reserved first,
138	 * then (and always) gd struct space will be reserved
139	 */
140	move.l	%sp, -(%sp)
141	bsr	board_init_f_alloc_reserve
142
143	/* update stack and frame-pointers */
144	move.l	%d0, %sp
145	move.l	%sp, %fp
146
147	/* initialize reserved area */
148	move.l	%d0, -(%sp)
149	bsr	board_init_f_init_reserve
150
151	/* run low-level CPU init code (from flash) */
152	bsr	cpu_init_f
153
154	/* run low-level board init code (from flash) */
155	clr.l	%sp@-
156	bsr	board_init_f
157
158	/* board_init_f() does not return */
159
160/******************************************************************************/
161
162/*
163 * void relocate_code (addr_sp, gd, addr_moni)
164 *
165 * This "function" does not return, instead it continues in RAM
166 * after relocating the monitor code.
167 *
168 */
169.globl relocate_code
170relocate_code:
171	link.w	%a6,#0
172	move.l	8(%a6), %sp	/* set new stack pointer */
173	move.l	12(%a6), %d0	/* Save copy of Global Data pointer */
174	move.l	16(%a6), %a0	/* Save copy of Destination Address */
175
176	move.l	#CONFIG_SYS_MONITOR_BASE, %a1
177	move.l	#__init_end, %a2
178	move.l	%a0, %a3
179	/* copy the code to RAM */
1801:
181	move.l	(%a1)+, (%a3)+
182	cmp.l	%a1,%a2
183	bgt.s	1b
184
185/*
186 * We are done. Do not return, instead branch to second part of board
187 * initialization, now running from RAM.
188 */
189	move.l	%a0, %a1
190	add.l	#(in_ram - CONFIG_SYS_MONITOR_BASE), %a1
191	jmp	(%a1)
192
193in_ram:
194
195clear_bss:
196	/*
197	 * Now clear BSS segment
198	 */
199	move.l	%a0, %a1
200	add.l	#(_sbss - CONFIG_SYS_MONITOR_BASE), %a1
201	move.l	%a0, %d1
202	add.l	#(_ebss - CONFIG_SYS_MONITOR_BASE), %d1
2036:
204	clr.l	(%a1)+
205	cmp.l	%a1,%d1
206	bgt.s	6b
207
208	/*
209	 * fix got table in RAM
210	 */
211	move.l	%a0, %a1
212	add.l	#(__got_start - CONFIG_SYS_MONITOR_BASE), %a1
213
214	/* fix got pointer register a5 */
215	move.l	%a1,%a5
216
217	move.l	%a0, %a2
218	add.l	#(__got_end - CONFIG_SYS_MONITOR_BASE), %a2
219
2207:
221	move.l	(%a1),%d1
222	sub.l	#_start, %d1
223	add.l	%a0,%d1
224	move.l	%d1,(%a1)+
225	cmp.l	%a2, %a1
226	bne	7b
227
228	/* calculate relative jump to board_init_r in ram */
229	move.l	%a0, %a1
230	add.l	#(board_init_r - CONFIG_SYS_MONITOR_BASE), %a1
231
232	/* set parameters for board_init_r */
233	move.l	%a0,-(%sp)	/* dest_addr */
234	move.l	%d0,-(%sp)	/* gd */
235#if defined(DEBUG) && (CONFIG_SYS_TEXT_BASE!=CONFIG_SYS_INT_FLASH_BASE) && \
236    defined(CONFIG_SYS_HALT_BEFOR_RAM_JUMP)
237	halt
238#endif
239	jsr	(%a1)
240
241/******************************************************************************/
242
243/* exception code */
244.globl _fault
245_fault:
246	bra	_fault
247
248.globl _exc_handler
249_exc_handler:
250	SAVE_ALL
251	movel	%sp,%sp@-
252	bsr	exc_handler
253	addql	#4,%sp
254	RESTORE_ALL
255
256.globl _int_handler
257_int_handler:
258	SAVE_ALL
259	movel	%sp,%sp@-
260	bsr	int_handler
261	addql	#4,%sp
262	RESTORE_ALL
263
264/******************************************************************************/
265
266.globl version_string
267version_string:
268.ascii	U_BOOT_VERSION
269.ascii	" (", U_BOOT_DATE, " - ", U_BOOT_TIME, ")"
270.ascii	CONFIG_IDENT_STRING, "\0"
271.align	4
272