srt0.S revision 1.6 1 /* $NetBSD: srt0.S,v 1.6 1999/07/31 00:45:28 thorpej Exp $ */
2
3 /*
4 * Copyright (c) 1988 University of Utah.
5 * Copyright (c) 1982, 1990, 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * the Systems Programming Group of the University of Utah Computer
10 * Science Department.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. All advertising materials mentioning features or use of this software
21 * must display the following acknowledgement:
22 * This product includes software developed by the University of
23 * California, Berkeley and its contributors.
24 * 4. Neither the name of the University nor the names of its contributors
25 * may be used to endorse or promote products derived from this software
26 * without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * SUCH DAMAGE.
39 *
40 * from: Utah $Hdr: srt0.c 1.18 92/12/21$
41 *
42 * @(#)srt0.c 8.1 (Berkeley) 6/10/93
43 */
44
45 /*
46 * Startup code for standalone system
47 */
48
49 /* For machineid and mmuid constants */
50 #include <machine/hp300spu.h>
51
52 /* For _C_LABEL() and friends. */
53 #include <machine/asm.h>
54
55 STACK = 0xfffff000 | below the ROM page
56 BOOTTYPE = 0xfffffdc0
57 LOWRAM = 0xfffffdce
58 SYSFLAG = 0xfffffed2 | system flags
59 MSUS = 0xfffffedc | MSUS (?) structure
60 VECTORS = 0xfffffee0 | beginning of jump vectors
61 NMIRESET = 0xffffff9c | reset vector
62 BUSERR = 0xfffffffc
63 MAXADDR = 0xfffff000
64 NBPG = 4096
65 MMUCMD = 0x005f400c | MMU command/status register
66
67 .data
68 GLOBAL(bootdev)
69 .long 0
70
71 GLOBAL(howto)
72 .long 0
73
74 GLOBAL(lowram)
75 .long 0
76
77 GLOBAL(machineid)
78 .long 0
79
80 .text
81 ASENTRY_NOPROFILE(begin)
82 movl #STACK,sp
83 moveq #47,d0 | # of vectors - 1
84 movl #VECTORS+2,a0 | addr part of first vector
85 1:
86 movl #_ASM_LABEL(__trap),a0@ | make it direct to __trap
87 addql #6,a0 | move to next vector addr
88 dbf d0,1b | go til done
89 movl #NMIRESET,a0 | NMI keyboard reset addr
90 movl #nmi,a0@ | catch in reset routine
91
92 /*
93 * Determine our SPU type and look for internal HP-IB
94 */
95 lea _C_LABEL(machineid),a0
96 movl #0x808,d0
97 movc d0,cacr | clear and disable on-chip cache(s)
98 movl #0x200,d0 | data freeze bit
99 movc d0,cacr | only exists on 68030
100 movc cacr,d0 | read it back
101 tstl d0 | zero?
102 jeq not68030 | yes, we have 68020/68040
103
104 movl #0x808,d0
105 movc d0,cacr | clear data freeze bit again
106
107 /*
108 * 68030 models
109 */
110
111 movl #0x80,MMUCMD | set magic cookie
112 movl MMUCMD,d0 | read it back
113 btst #7,d0 | cookie still on?
114 jeq not370 | no, 360 or 375
115 movl #HP_370,a0@ | consider a 370 for now
116 movl #0,MMUCMD | clear magic cookie
117 movl MMUCMD,d0 | read it back
118 btst #7,d0 | still on?
119 jeq ihpibcheck | no, a 370
120 movl #HP_340,a0@ | yes, must be a 340
121 jra ihpibcheck
122
123 not370:
124 movl #HP_360,a0@ | type is at least a 360
125 movl #0,MMUCMD | clear magic cookie2
126 movl MMUCMD,d0 | read it back
127 btst #16,d0 | still on?
128 jeq ihpibcheck | no, a 360
129 lsrl #MMUID_SHIFT,d0 | save MMU ID
130 andl #MMUID_MASK,d0
131 cmpb #MMUID_345,d0 | are we a 345?
132 jeq isa345
133 cmpb #MMUID_375,d0 | how about a 375?
134 jeq isa375
135 movl #HP_400,a0@ | must be a 400
136 jra ihpibcheck
137 isa345:
138 movl #HP_345,a0@
139 jra ihpibcheck
140 isa375:
141 movl #HP_375,a0@
142 jra ihpibcheck
143
144 /*
145 * End of 68030 section
146 */
147
148 not68030:
149 bset #31,d0 | data cache enable bit
150 movc d0,cacr | only exists on 68040
151 movc cacr,d0 | read it back
152 tstl d0 | zero?
153 beq is68020 | yes, we have 68020
154 moveq #0,d0 | now turn it back off
155 movec d0,cacr | before we access any data
156
157 .long 0x4e7b0004 | movc d0,itt0
158 .long 0x4e7b0005 | movc d0,itt1
159 .long 0x4e7b0006 | movc d0,dtt0
160 .long 0x4e7b0007 | movc d0,dtt1
161 .word 0xf4d8 | cinva bc
162
163 /*
164 * 68040 models
165 */
166
167 movl MMUCMD,d0 | get MMU ID
168 lsrl #MMUID_SHIFT,d0
169 andl #MMUID_MASK,d0
170 cmpb #MMUID_425_T,d0 | are we a 425t?
171 jeq isa425
172 cmpb #MMUID_425_S,d0 | how about 425s?
173 jeq isa425
174 cmpb #MMUID_425_E,d0 | or maybe a 425e?
175 jeq isa425
176 cmpb #MMUID_433_T,d0 | or a 433t?
177 jeq isa433
178 cmpb #MMUID_433_S,d0 | or a 433s?
179 jeq isa433
180 cmpb #MMUID_385,d0 | or a 385?
181 jeq isa385
182 movl #HP_380,a0@ | guess we are a 380
183 jra ihpibcheck
184 isa425:
185 movl #HP_425,a0@
186 jra ihpibcheck
187 isa433:
188 movl #HP_433,a0@
189 jra ihpibcheck
190 isa385:
191 movl #HP_385,a0@
192 jra ihpibcheck
193
194 /*
195 * End 68040 section
196 */
197
198 /*
199 * 68020 models
200 */
201
202 is68020:
203 movl #HP_330,a0@ | consider a 330 for now
204 movl #1,MMUCMD | a 68020, write HP MMU location
205 movl MMUCMD,d0 | read it back
206 btst #0,d0 | zero?
207 jeq ihpibcheck | yes, a 330
208 movl #HP_320,a0@ | no, consider a 320 for now
209 movl #0x80,MMUCMD | set magic cookie
210 movl MMUCMD,d0 | read it back
211 btst #7,d0 | cookie still on?
212 jeq ihpibcheck | no, just a 320
213 movl #HP_350,a0@ | yes, a 350
214
215 /*
216 * End 68020 section
217 */
218
219 ihpibcheck:
220 movl #0,MMUCMD | make sure MMU is off
221 btst #5,SYSFLAG | do we have an internal HP-IB?
222 jeq boottype | yes, continue
223 clrl _C_LABEL(internalhpib) | no, clear the internal address
224 /*
225 * If this is a reboot, extract howto/bootdev stored by kernel
226 */
227 boottype:
228 cmpw #12,BOOTTYPE | is this a reboot (REQ_REBOOT)?
229 jne notreboot | no, skip
230 lea MAXADDR,a0 | find last page
231 movl a0@+,d7 | and extract howto, bootdev
232 movl a0@+,d6 | from where doboot() left them
233 jra boot1
234 /*
235 * At this point we do not know which logical device the MSUS select
236 * code refers to so we cannot construct bootdev. So we just punt
237 * and let configure() construct it.
238 */
239 notreboot:
240 moveq #0,d6 | make sure bootdev is invalid
241 cmpw #18,BOOTTYPE | does the user want to interact?
242 jeq askme | yes, go to it
243 moveq #0,d7 | default to RB_AUTOBOOT
244 jra boot1
245 askme:
246 moveq #3,d7 | default to RB_SINGLE|RB_ASKNAME
247 boot1:
248 movl d6,_C_LABEL(bootdev) | save bootdev and howto
249 movl d7,_C_LABEL(howto) | globally so all can access
250 movl LOWRAM,d0 | read lowram value from bootrom
251 /*
252 * Must preserve the scratch area for the BOOT ROM.
253 * Round up to the next 8k boundary.
254 */
255 addl #((2*NBPG)-1),d0
256 andl #-(2*NBPG),d0
257 movl d0,_C_LABEL(lowram) | stash that value
258 start:
259 movl #_C_LABEL(edata),a2 | start of BSS
260 movl #_C_LABEL(end),a3 | end
261 1:
262 clrb a2@+ | clear BSS
263 cmpl a2,a3 | done?
264 bne 1b | no, keep going
265 jsr _C_LABEL(configure) | configure critical devices
266 jsr _C_LABEL(main) | lets go
267 GLOBAL(_rtt)
268 movl #3,_C_LABEL(howto) | restarts get RB_SINGLE|RB_ASKNAME
269 jmp start
270
271 /*
272 * probe a location and see if it causes a bus error
273 */
274 ENTRY_NOPROFILE(badaddr)
275 movl BUSERR,_C_LABEL(_bsave) | save ROM bus error handler address
276 movl sp,_C_LABEL(_ssave) | and current stack pointer
277 movl #catchbad,BUSERR | plug in our handler
278 movl sp@(4),a0 | address to probe
279 movw a0@,d1 | do it
280 movl _C_LABEL(_bsave),BUSERR | if we got here, it did not fault
281 clrl d0 | return that this was not a bad addr
282 rts
283
284 catchbad:
285 movl _C_LABEL(_bsave),BUSERR | got a bus error, so restore
286 | old handler
287 movl _C_LABEL(_ssave),sp | manually restore stack
288 moveq #1,d0 | indicate that we got a fault
289 rts | return to caller of badaddr()
290
291 .data
292 GLOBAL(_bsave)
293 .long 0
294
295 GLOBAL(_ssave)
296 .long 0
297
298 ASENTRY_NOPROFILE(__trap)
299 moveml #0xFFFF,sp@- | save registers
300 movl sp,sp@- | push pointer to frame
301 jsr _C_LABEL(trap) | call C routine to deal with it
302 tstl d0
303 jeq Lstop
304 addql #4,sp
305 moveml sp@+,#0x7FFF
306 addql #8,sp
307 rte
308 Lstop:
309 stop #0x2700 | stop cold
310
311 ASENTRY_NOPROFILE(nmi)
312 movw #18,BOOTTYPE | mark as system switch
313 jsr _C_LABEL(kbdnmi) | clear the interrupt, and
314 | reset the system
315 stop #0 | SCREEEECH!
316
317 ENTRY_NOPROFILE(call_req_reboot)
318 jmp 0x1A4 | call ROM reboot function
319 rts | XXX: just in case?
320
321 ENTRY_NOPROFILE(romout)
322 movl sp@(4),d0 | line number
323 movl sp@(8),a0 | string
324 jsr 0x150 | do it
325 rts
326