xref: /openbmc/u-boot/arch/m68k/cpu/mcf530x/start.S (revision e04f9d0c)
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	/* put relocation table address to a5 */
130	move.l #__got_start, %a5
131
132	/* setup stack initially on top of internal static ram  */
133	move.l  #(CONFIG_SYS_INIT_RAM_ADDR + CONFIG_SYS_INIT_RAM_SIZE), %sp
134
135	/*
136	 * if configured, malloc_f arena will be reserved first,
137	 * then (and always) gd struct space will be reserved
138	 */
139	move.l	%sp, -(%sp)
140	bsr	board_init_f_alloc_reserve
141
142	/* update stack and frame-pointers */
143	move.l  %d0, %sp
144	move.l  %sp, %fp
145
146	/* initialize reserved area */
147	move.l  %d0, -(%sp)
148	bsr     board_init_f_init_reserve
149
150	/* run low-level CPU init code (from flash) */
151	bsr cpu_init_f
152
153	/* run low-level board init code (from flash) */
154	clr.l   %sp@-
155	bsr board_init_f
156
157	/* board_init_f() does not return */
158
159/*--------------------------------------------------------------------------*/
160
161/*
162 * void relocate_code (addr_sp, gd, addr_moni)
163 *
164 * This "function" does not return, instead it continues in RAM
165 * after relocating the monitor code.
166 *
167 */
168	.globl	relocate_code
169relocate_code:
170	link.w	%a6,#0
171	move.l	8(%a6), %sp	/* set new stack pointer */
172	move.l	12(%a6), %d0	/* Save copy of Global Data pointer */
173	move.l	16(%a6), %a0	/* Save copy of Destination Address */
174
175	move.l	#CONFIG_SYS_MONITOR_BASE, %a1
176	move.l	#__init_end, %a2
177	move.l	%a0, %a3
178	/* copy the code to RAM */
1791:
180	move.l	(%a1)+, (%a3)+
181	cmp.l	%a1,%a2
182	bgt.s	1b
183
184/*
185 * We are done. Do not return, instead branch to second part of board
186 * initialization, now running from RAM.
187 */
188	move.l	%a0, %a1
189	add.l	#(in_ram - CONFIG_SYS_MONITOR_BASE), %a1
190	jmp	(%a1)
191
192in_ram:
193
194clear_bss:
195	/*
196	 * Now clear BSS segment
197	 */
198	move.l	%a0, %a1
199	add.l	#(_sbss - CONFIG_SYS_MONITOR_BASE), %a1
200	move.l	%a0, %d1
201	add.l	#(_ebss - CONFIG_SYS_MONITOR_BASE), %d1
2026:
203	clr.l	(%a1)+
204	cmp.l	%a1,%d1
205	bgt.s	6b
206
207	/*
208	 * fix got table in RAM
209	 */
210	move.l	%a0, %a1
211	add.l	#(__got_start - CONFIG_SYS_MONITOR_BASE), %a1
212	/* * fix got pointer register a5 */
213	move.l	%a1,%a5
214
215	move.l	%a0, %a2
216	add.l	#(__got_end - CONFIG_SYS_MONITOR_BASE), %a2
217
2187:
219	move.l	(%a1),%d1
220	sub.l	#_start, %d1
221	add.l	%a0,%d1
222	move.l	%d1,(%a1)+
223	cmp.l	%a2, %a1
224	bne	7b
225
226	/* calculate relative jump to board_init_r in ram */
227	move.l	%a0, %a1
228	add.l	#(board_init_r - CONFIG_SYS_MONITOR_BASE), %a1
229
230	/* set parameters for board_init_r */
231	move.l	%a0,-(%sp)	/* dest_addr */
232	move.l	%d0,-(%sp)	/* gd */
233#if defined(DEBUG) && (CONFIG_SYS_TEXT_BASE!=CONFIG_SYS_INT_FLASH_BASE) && \
234    defined(CONFIG_SYS_HALT_BEFOR_RAM_JUMP)
235	halt
236#endif
237	jsr	(%a1)
238
239/*--------------------------------------------------------------------------*/
240/* exception code */
241	.globl _fault
242_fault:
243	bra	_fault
244
245	.globl	_exc_handler
246_exc_handler:
247	SAVE_ALL
248	movel	%sp,%sp@-
249	bsr 	exc_handler
250	addql	#4,%sp
251	RESTORE_ALL
252
253	.globl	_int_handler
254_int_handler:
255	SAVE_ALL
256	movel	%sp,%sp@-
257	bsr 	int_handler
258	addql	#4,%sp
259	RESTORE_ALL
260
261/*--------------------------------------------------------------------------*/
262
263	.globl	version_string
264version_string:
265	.ascii	U_BOOT_VERSION
266	.ascii	" (", U_BOOT_DATE, " - ", U_BOOT_TIME, ")"
267	.ascii	CONFIG_IDENT_STRING, "\0"
268	.align	4
269