xref: /openbmc/u-boot/arch/m68k/cpu/mcf530x/start.S (revision 2399e401)
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#define _START	_start
14#define _FAULT	_fault
15
16
17.macro  SAVE_ALL
18	move.w	#0x2700,%sr;		/* disable intrs */
19	subl	#60,%sp;		/* space for 15 regs */
20	moveml	%d0-%d7/%a0-%a6,%sp@
21.endm
22
23.macro  RESTORE_ALL
24	moveml	%sp@,%d0-%d7/%a0-%a6;
25	addl	#60,%sp;		/* space for 15 regs */
26	rte
27.endm
28
29/* If we come from a pre-loader we don't need an initial exception
30 * table.
31 */
32#if !defined(CONFIG_MONITOR_IS_IN_RAM)
33
34.text
35
36/*
37 * Vector table. This is used for initial platform startup.
38 * These vectors are to catch any un-intended traps.
39 */
40_vectors:
41/* Flash offset is 0 until we setup CS0 */
42.long	0x00000000
43#if defined(CONFIG_M5307) && \
44	   (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.globl _start
91_start:
92	nop
93	nop
94	move.w	#0x2700,%sr
95
96	/* set MBAR address + valid flag */
97	move.l	#(CONFIG_SYS_MBAR + 1), %d0
98	move.c	%d0, %MBAR
99
100	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + 1), %d0
101	move.c	%d0, %RAMBAR
102
103	/* DS 4.8.2 (Cache Organization) invalidate and disable cache */
104        move.l	#CF_CACR_CINVA, %d0
105        movec	%d0, %CACR
106        move.l	#0, %d0
107        movec	%d0, %ACR0
108        movec	%d0, %ACR1
109
110	/*
111	 * if we come from a pre-loader we have no exception table and
112	 * therefore no VBR to set
113	 */
114#if !defined(CONFIG_MONITOR_IS_IN_RAM)
115	move.l	#CONFIG_SYS_FLASH_BASE, %d0
116	movec	%d0, %VBR
117#endif
118
119	/* initialize general use internal ram */
120	move.l	#0, %d0
121	move.l	#(ICACHE_STATUS), %a1	/* icache */
122	move.l	#(DCACHE_STATUS), %a2	/* dcache */
123	move.l	%d0, (%a1)
124	move.l	%d0, (%a2)
125
126	/* put relocation table address to a5 */
127	move.l	#__got_start, %a5
128
129	/* setup stack initially on top of internal static ram  */
130	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_RAM_SIZE), %sp
131
132	/*
133	 * if configured, malloc_f arena will be reserved first,
134	 * then (and always) gd struct space will be reserved
135	 */
136	move.l	%sp, -(%sp)
137	bsr	board_init_f_alloc_reserve
138
139	/* update stack and frame-pointers */
140	move.l	%d0, %sp
141	move.l	%sp, %fp
142
143	/* initialize reserved area */
144	move.l	%d0, -(%sp)
145	bsr	board_init_f_init_reserve
146
147	/* run low-level CPU init code (from flash) */
148	bsr	cpu_init_f
149
150	/* run low-level board init code (from flash) */
151	clr.l	%sp@-
152	bsr	board_init_f
153
154	/* board_init_f() does not return */
155
156/******************************************************************************/
157
158/*
159 * void relocate_code (addr_sp, gd, addr_moni)
160 *
161 * This "function" does not return, instead it continues in RAM
162 * after relocating the monitor code.
163 *
164 */
165.globl relocate_code
166relocate_code:
167	link.w	%a6,#0
168	move.l	8(%a6), %sp	/* set new stack pointer */
169	move.l	12(%a6), %d0	/* Save copy of Global Data pointer */
170	move.l	16(%a6), %a0	/* Save copy of Destination Address */
171
172	move.l	#CONFIG_SYS_MONITOR_BASE, %a1
173	move.l	#__init_end, %a2
174	move.l	%a0, %a3
175	/* copy the code to RAM */
1761:
177	move.l	(%a1)+, (%a3)+
178	cmp.l	%a1,%a2
179	bgt.s	1b
180
181/*
182 * We are done. Do not return, instead branch to second part of board
183 * initialization, now running from RAM.
184 */
185	move.l	%a0, %a1
186	add.l	#(in_ram - CONFIG_SYS_MONITOR_BASE), %a1
187	jmp	(%a1)
188
189in_ram:
190
191clear_bss:
192	/*
193	 * Now clear BSS segment
194	 */
195	move.l	%a0, %a1
196	add.l	#(_sbss - CONFIG_SYS_MONITOR_BASE), %a1
197	move.l	%a0, %d1
198	add.l	#(_ebss - CONFIG_SYS_MONITOR_BASE), %d1
1996:
200	clr.l	(%a1)+
201	cmp.l	%a1,%d1
202	bgt.s	6b
203
204	/*
205	 * fix got table in RAM
206	 */
207	move.l	%a0, %a1
208	add.l	#(__got_start - CONFIG_SYS_MONITOR_BASE), %a1
209
210	/* fix got pointer register a5 */
211	move.l	%a1,%a5
212
213	move.l	%a0, %a2
214	add.l	#(__got_end - CONFIG_SYS_MONITOR_BASE), %a2
215
2167:
217	move.l	(%a1),%d1
218	sub.l	#_start, %d1
219	add.l	%a0,%d1
220	move.l	%d1,(%a1)+
221	cmp.l	%a2, %a1
222	bne	7b
223
224	/* calculate relative jump to board_init_r in ram */
225	move.l	%a0, %a1
226	add.l	#(board_init_r - CONFIG_SYS_MONITOR_BASE), %a1
227
228	/* set parameters for board_init_r */
229	move.l	%a0,-(%sp)	/* dest_addr */
230	move.l	%d0,-(%sp)	/* gd */
231#if defined(DEBUG) && (CONFIG_SYS_TEXT_BASE!=CONFIG_SYS_INT_FLASH_BASE) && \
232    defined(CONFIG_SYS_HALT_BEFOR_RAM_JUMP)
233	halt
234#endif
235	jsr	(%a1)
236
237/******************************************************************************/
238
239/* exception code */
240.globl _fault
241_fault:
242	bra	_fault
243
244.globl _exc_handler
245_exc_handler:
246	SAVE_ALL
247	movel	%sp,%sp@-
248	bsr	exc_handler
249	addql	#4,%sp
250	RESTORE_ALL
251
252.globl _int_handler
253_int_handler:
254	SAVE_ALL
255	movel	%sp,%sp@-
256	bsr	int_handler
257	addql	#4,%sp
258	RESTORE_ALL
259
260/******************************************************************************/
261
262.globl version_string
263version_string:
264.ascii	U_BOOT_VERSION
265.ascii	" (", U_BOOT_DATE, " - ", U_BOOT_TIME, ")"
266.ascii	CONFIG_IDENT_STRING, "\0"
267.align	4
268