xref: /openbmc/u-boot/arch/m68k/cpu/mcf530x/start.S (revision 6b44ae6b)
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 *	Vector table. This is used for initial platform startup.
41 *	These vectors are to catch any un-intended traps.
42 */
43_vectors:
44
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	.globl	_start
94_start:
95	nop
96	nop
97	move.w  #0x2700,%sr
98
99	/* set MBAR address + valid flag */
100	move.l	#(CONFIG_SYS_MBAR + 1), %d0
101	move.c	%d0, %MBAR
102
103	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + 1), %d0
104	move.c	%d0, %RAMBAR
105
106	/* DS 4.8.2 (Cache Organization) invalidate and disable cache */
107        move.l  #CF_CACR_CINVA, %d0
108        movec   %d0, %CACR
109        move.l  #0, %d0
110        movec   %d0, %ACR0
111        movec   %d0, %ACR1
112
113	/*
114	 * if we come from a pre-loader we have no exception table and
115	 * therefore no VBR to set
116	 */
117#if !defined(CONFIG_MONITOR_IS_IN_RAM)
118	move.l	#CONFIG_SYS_FLASH_BASE, %d0
119	movec	%d0, %VBR
120#endif
121
122	/* initialize general use internal ram */
123	move.l	#0, %d0
124	move.l	#(ICACHE_STATUS), %a1	/* icache */
125	move.l	#(DCACHE_STATUS), %a2	/* dcache */
126	move.l	%d0, (%a1)
127	move.l	%d0, (%a2)
128
129	/*
130	 * set stackpointer to internal sram end - 80
131	 * (global data struct size + some bytes)
132	 * get some stackspace for the first c-code,
133	 */
134	move.l	#(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_SP_OFFSET), %sp
135	clr.l   %sp@-
136
137	/* put relocation table address to a5 */
138	move.l #__got_start, %a5
139
140	/* run low-level CPU init code (from flash) */
141	bsr cpu_init_f
142
143	/* run low-level board init code (from flash) */
144	bsr board_init_f
145
146	/* board_init_f() does not return */
147
148/*--------------------------------------------------------------------------*/
149
150/*
151 * void relocate_code (addr_sp, gd, addr_moni)
152 *
153 * This "function" does not return, instead it continues in RAM
154 * after relocating the monitor code.
155 *
156 */
157	.globl	relocate_code
158relocate_code:
159	link.w	%a6,#0
160	move.l	8(%a6), %sp	/* set new stack pointer */
161	move.l	12(%a6), %d0	/* Save copy of Global Data pointer */
162	move.l	16(%a6), %a0	/* Save copy of Destination Address */
163
164	move.l	#CONFIG_SYS_MONITOR_BASE, %a1
165	move.l	#__init_end, %a2
166	move.l	%a0, %a3
167	/* copy the code to RAM */
1681:
169	move.l	(%a1)+, (%a3)+
170	cmp.l	%a1,%a2
171	bgt.s	1b
172
173/*
174 * We are done. Do not return, instead branch to second part of board
175 * initialization, now running from RAM.
176 */
177	move.l	%a0, %a1
178	add.l	#(in_ram - CONFIG_SYS_MONITOR_BASE), %a1
179	jmp	(%a1)
180
181in_ram:
182
183clear_bss:
184	/*
185	 * Now clear BSS segment
186	 */
187	move.l	%a0, %a1
188	add.l	#(_sbss - CONFIG_SYS_MONITOR_BASE), %a1
189	move.l	%a0, %d1
190	add.l	#(_ebss - CONFIG_SYS_MONITOR_BASE), %d1
1916:
192	clr.l	(%a1)+
193	cmp.l	%a1,%d1
194	bgt.s	6b
195
196	/*
197	 * fix got table in RAM
198	 */
199	move.l	%a0, %a1
200	add.l	#(__got_start - CONFIG_SYS_MONITOR_BASE), %a1
201	/* * fix got pointer register a5 */
202	move.l	%a1,%a5
203
204	move.l	%a0, %a2
205	add.l	#(__got_end - CONFIG_SYS_MONITOR_BASE), %a2
206
2077:
208	move.l	(%a1),%d1
209	sub.l	#_start, %d1
210	add.l	%a0,%d1
211	move.l	%d1,(%a1)+
212	cmp.l	%a2, %a1
213	bne	7b
214
215	/* calculate relative jump to board_init_r in ram */
216	move.l	%a0, %a1
217	add.l	#(board_init_r - CONFIG_SYS_MONITOR_BASE), %a1
218
219	/* set parameters for board_init_r */
220	move.l	%a0,-(%sp)	/* dest_addr */
221	move.l	%d0,-(%sp)	/* gd */
222#if defined(DEBUG) && (CONFIG_SYS_TEXT_BASE!=CONFIG_SYS_INT_FLASH_BASE) && \
223    defined(CONFIG_SYS_HALT_BEFOR_RAM_JUMP)
224	halt
225#endif
226	jsr	(%a1)
227
228/*--------------------------------------------------------------------------*/
229/* exception code */
230	.globl _fault
231_fault:
232	bra	_fault
233
234	.globl	_exc_handler
235_exc_handler:
236	SAVE_ALL
237	movel	%sp,%sp@-
238	bsr 	exc_handler
239	addql	#4,%sp
240	RESTORE_ALL
241
242	.globl	_int_handler
243_int_handler:
244	SAVE_ALL
245	movel	%sp,%sp@-
246	bsr 	int_handler
247	addql	#4,%sp
248	RESTORE_ALL
249
250/*--------------------------------------------------------------------------*/
251
252	.globl	version_string
253version_string:
254	.ascii	U_BOOT_VERSION
255	.ascii	" (", U_BOOT_DATE, " - ", U_BOOT_TIME, ")"
256	.ascii	CONFIG_IDENT_STRING, "\0"
257	.align	4
258