xref: /netbsd-src/sys/arch/mac68k/mac68k/pmap_bootstrap.c (revision 6deb2c22d20de1d75d538e8a5c57b573926fd157)
1 /*	$NetBSD: pmap_bootstrap.c,v 1.78 2009/08/11 17:04:18 matt Exp $	*/
2 
3 /*
4  * Copyright (c) 1991, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * the Systems Programming Group of the University of Utah Computer
9  * Science Department.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	@(#)pmap_bootstrap.c	8.1 (Berkeley) 6/10/93
36  */
37 
38 #include <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: pmap_bootstrap.c,v 1.78 2009/08/11 17:04:18 matt Exp $");
40 
41 #include "opt_ddb.h"
42 #include "opt_kgdb.h"
43 #include "zsc.h"
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/reboot.h>
48 
49 #include <uvm/uvm_extern.h>
50 
51 #include <machine/pte.h>
52 #include <machine/vmparam.h>
53 #include <machine/cpu.h>
54 #include <machine/pmap.h>
55 #include <machine/autoconf.h>
56 #include <machine/video.h>
57 
58 #include <mac68k/mac68k/macrom.h>
59 
60 #define PA2VA(v, t)	(t)((u_int)(v) - firstpa)
61 
62 extern char *etext;
63 extern char *extiobase, *proc0paddr;
64 
65 extern paddr_t avail_start;
66 extern paddr_t avail_end;
67 
68 #if NZSC > 0
69 extern	int	zsinited;
70 #endif
71 
72 /*
73  * These are used to map the RAM:
74  */
75 int	numranges;	/* = 0 == don't use the ranges */
76 u_long	low[8];
77 u_long	high[8];
78 u_long	maxaddr;	/* PA of the last physical page */
79 int	vidlen;
80 #define VIDMAPSIZE	btoc(vidlen)
81 static vaddr_t	newvideoaddr;
82 
83 extern void *	ROMBase;
84 
85 /*
86  * Special purpose kernel virtual addresses, used for mapping
87  * physical pages for a variety of temporary or permanent purposes:
88  *
89  *	CADDR1, CADDR2:	pmap zero/copy operations
90  *	vmmap:		/dev/mem, crash dumps, parity error checking
91  *	msgbufaddr:	kernel message buffer
92  */
93 void *CADDR1, *CADDR2;
94 char *vmmap;
95 void *msgbufaddr;
96 
97 void	pmap_bootstrap(paddr_t, paddr_t);
98 void	bootstrap_mac68k(int);
99 
100 /*
101  * Bootstrap the VM system.
102  *
103  * This is called with the MMU either on or off.  If it's on, we assume
104  * that it's mapped with the same PA <=> LA mapping that we eventually
105  * want.  The page sizes and the protections will be wrong, anyway.
106  *
107  * nextpa is the first address following the loaded kernel.  On a IIsi
108  * on 12 May 1996, that was 0xf9000 beyond firstpa.
109  */
110 void
111 pmap_bootstrap(paddr_t nextpa, paddr_t firstpa)
112 {
113 	paddr_t kstpa, kptpa, kptmpa, p0upa;
114 	u_int nptpages, kstsize;
115 	paddr_t avail_next;
116 	int avail_remaining;
117 	int avail_range;
118 	int i;
119 	st_entry_t protoste, *ste;
120 	pt_entry_t protopte, *pte, *epte;
121 	extern char start[];
122 
123 	vidlen = m68k_round_page(mac68k_video.mv_height *
124 	    mac68k_video.mv_stride + m68k_page_offset(mac68k_video.mv_phys));
125 
126 	/*
127 	 * Calculate important physical addresses:
128 	 *
129 	 *	kstpa		kernel segment table	1 page (!040)
130 	 *						N pages (040)
131 	 *
132 	 *	kptpa		statically allocated
133 	 *			kernel PT pages		Sysptsize+ pages
134 	 *
135 	 * [ Sysptsize is the number of pages of PT, IIOMAPSIZE and
136 	 *   NBMAPSIZE are the number of PTEs, hence we need to round
137 	 *   the total to a page boundary with IO maps at the end. ]
138 	 *
139 	 *	kptmpa		kernel PT map		1 page
140 	 *
141 	 *	p0upa		proc 0 u-area		UPAGES pages
142 	 *
143 	 */
144 	if (mmutype == MMU_68040)
145 		kstsize = MAXKL2SIZE / (NPTEPG/SG4_LEV2SIZE);
146 	else
147 		kstsize = 1;
148 	kstpa = nextpa;
149 	nextpa += kstsize * PAGE_SIZE;
150 	kptmpa = nextpa;
151 	nextpa += PAGE_SIZE;
152 	p0upa = nextpa;
153 	nextpa += USPACE;
154 	kptpa = nextpa;
155 	nptpages = Sysptsize +
156 		(IIOMAPSIZE + ROMMAPSIZE + VIDMAPSIZE + NPTEPG - 1) / NPTEPG;
157 	nextpa += nptpages * PAGE_SIZE;
158 
159 	for (i = 0; i < numranges; i++)
160 		if (low[i] <= firstpa && firstpa < high[i])
161 			break;
162 	if (i >= numranges || nextpa > high[i]) {
163 		if (mac68k_machine.do_graybars) {
164 			printf("Failure in NetBSD boot; ");
165 			if (i < numranges)
166 				printf("nextpa=0x%lx, high[%d]=0x%lx.\n",
167 				    nextpa, i, high[i]);
168 			else
169 				printf("can't find kernel RAM segment.\n");
170 			printf("You're hosed!  Try booting with 32-bit ");
171 			printf("addressing enabled in the memory control ");
172 			printf("panel.\n");
173 			printf("Older machines may need Mode32 to get that ");
174 			printf("option.\n");
175 		}
176 		panic("Cannot work with the current memory mappings.");
177 	}
178 
179 	/*
180 	 * Initialize segment table and kernel page table map.
181 	 *
182 	 * On 68030s and earlier MMUs the two are identical except for
183 	 * the valid bits so both are initialized with essentially the
184 	 * same values.  On the 68040, which has a mandatory 3-level
185 	 * structure, the segment table holds the level 1 table and part
186 	 * (or all) of the level 2 table and hence is considerably
187 	 * different.  Here the first level consists of 128 descriptors
188 	 * (512 bytes) each mapping 32mb of address space.  Each of these
189 	 * points to blocks of 128 second level descriptors (512 bytes)
190 	 * each mapping 256kb.  Note that there may be additional "segment
191 	 * table" pages depending on how large MAXKL2SIZE is.
192 	 *
193 	 * XXX cramming two levels of mapping into the single "segment"
194 	 * table on the 68040 is intended as a temporary hack to get things
195 	 * working.  The 224mb of address space that this allows will most
196 	 * likely be insufficient in the future (at least for the kernel).
197 	 */
198 	if (mmutype == MMU_68040) {
199 		int num;
200 
201 		/*
202 		 * First invalidate the entire "segment table" pages
203 		 * (levels 1 and 2 have the same "invalid" value).
204 		 */
205 		pte = PA2VA(kstpa, u_int *);
206 		epte = &pte[kstsize * NPTEPG];
207 		while (pte < epte)
208 			*pte++ = SG_NV;
209 		/*
210 		 * Initialize level 2 descriptors (which immediately
211 		 * follow the level 1 table).  We need:
212 		 *	NPTEPG / SG4_LEV3SIZE
213 		 * level 2 descriptors to map each of the nptpages
214 		 * pages of PTEs.  Note that we set the "used" bit
215 		 * now to save the HW the expense of doing it.
216 		 */
217 		num = nptpages * (NPTEPG / SG4_LEV3SIZE);
218 		pte = &(PA2VA(kstpa, u_int *))[SG4_LEV1SIZE];
219 		epte = &pte[num];
220 		protoste = kptpa | SG_U | SG_RW | SG_V;
221 		while (pte < epte) {
222 			*pte++ = protoste;
223 			protoste += (SG4_LEV3SIZE * sizeof(st_entry_t));
224 		}
225 		/*
226 		 * Initialize level 1 descriptors.  We need:
227 		 *	roundup(num, SG4_LEV2SIZE) / SG4_LEV2SIZE
228 		 * level 1 descriptors to map the `num' level 2's.
229 		 */
230 		pte = PA2VA(kstpa, u_int *);
231 		epte = &pte[roundup(num, SG4_LEV2SIZE) / SG4_LEV2SIZE];
232 		protoste = (u_int)&pte[SG4_LEV1SIZE] | SG_U | SG_RW | SG_V;
233 		while (pte < epte) {
234 			*pte++ = protoste;
235 			protoste += (SG4_LEV2SIZE * sizeof(st_entry_t));
236 		}
237 		/*
238 		 * Initialize the final level 1 descriptor to map the last
239 		 * block of level 2 descriptors.
240 		 */
241 		ste = &(PA2VA(kstpa, u_int*))[SG4_LEV1SIZE-1];
242 		pte = &(PA2VA(kstpa, u_int*))[kstsize*NPTEPG - SG4_LEV2SIZE];
243 		*ste = (u_int)pte | SG_U | SG_RW | SG_V;
244 		/*
245 		 * Now initialize the final portion of that block of
246 		 * descriptors to map Sysmap.
247 		 */
248 		pte = &(PA2VA(kstpa, u_int*))
249 				[kstsize*NPTEPG - NPTEPG/SG4_LEV3SIZE];
250 		epte = &pte[NPTEPG/SG4_LEV3SIZE];
251 		protoste = kptmpa | SG_U | SG_RW | SG_V;
252 		while (pte < epte) {
253 			*pte++ = protoste;
254 			protoste += (SG4_LEV3SIZE * sizeof(st_entry_t));
255 		}
256 		/*
257 		 * Initialize Sysptmap
258 		 */
259 		pte = PA2VA(kptmpa, u_int *);
260 		epte = &pte[nptpages];
261 		protopte = kptpa | PG_RW | PG_CI | PG_V;
262 		while (pte < epte) {
263 			*pte++ = protopte;
264 			protopte += PAGE_SIZE;
265 		}
266 		/*
267 		 * Invalidate all but the last remaining entry.
268 		 */
269 		epte = &(PA2VA(kptmpa, u_int *))[NPTEPG - 1];
270 		while (pte < epte) {
271 			*pte++ = PG_NV;
272 		}
273 		/*
274 		 * Initialize the last one to point to Sysptmap.
275 		 */
276 		*pte = kptmpa | PG_RW | PG_CI | PG_V;
277 	} else {
278 		/*
279 		 * Map the page table pages in both the HW segment table
280 		 * and the software Sysptmap.
281 		 */
282 		ste = PA2VA(kstpa, u_int*);
283 		pte = PA2VA(kptmpa, u_int*);
284 		epte = &pte[nptpages];
285 		protoste = kptpa | SG_RW | SG_V;
286 		protopte = kptpa | PG_RW | PG_CI | PG_V;
287 		while (pte < epte) {
288 			*ste++ = protoste;
289 			*pte++ = protopte;
290 			protoste += PAGE_SIZE;
291 			protopte += PAGE_SIZE;
292 		}
293 		/*
294 		 * Invalidate all but the last remaining entries in both.
295 		 */
296 		epte = &(PA2VA(kptmpa, u_int *))[NPTEPG - 1];
297 		while (pte < epte) {
298 			*ste++ = SG_NV;
299 			*pte++ = PG_NV;
300 		}
301 		/*
302 		 * Initialize the last one to point to Sysptmap.
303 		 */
304 		*ste = kptmpa | SG_RW | SG_V;
305 		*pte = kptmpa | PG_RW | PG_CI | PG_V;
306 	}
307 
308 	/*
309 	 * Initialize kernel page table.
310 	 * Start by invalidating the `nptpages' that we have allocated.
311 	 */
312 	pte = PA2VA(kptpa, u_int *);
313 	epte = &pte[nptpages * NPTEPG];
314 	while (pte < epte)
315 		*pte++ = PG_NV;
316 
317 	/*
318 	 * Validate PTEs for kernel text (RO).
319 	 * Pages up to "start" must be writable for the ROM.
320 	 */
321 	pte = &(PA2VA(kptpa, u_int *))[m68k_btop(KERNBASE)];
322 	/* XXX why KERNBASE relative? */
323 	epte = &pte[m68k_btop(m68k_round_page(start))];
324 	protopte = firstpa | PG_RW | PG_V;
325 	while (pte < epte) {
326 		*pte++ = protopte;
327 		protopte += PAGE_SIZE;
328 	}
329 	/* XXX why KERNBASE relative? */
330 	epte = &pte[m68k_btop(m68k_trunc_page(&etext))];
331 	protopte = (protopte & ~PG_PROT) | PG_RO;
332 	while (pte < epte) {
333 		*pte++ = protopte;
334 		protopte += PAGE_SIZE;
335 	}
336 	/*
337 	 * Validate PTEs for kernel data/bss, dynamic data allocated
338 	 * by us so far (nextpa - firstpa bytes), and pages for proc0
339 	 * u-area and page table allocated below (RW).
340 	 */
341 	epte = &(PA2VA(kptpa, u_int *))[m68k_btop(nextpa - firstpa)];
342 	protopte = (protopte & ~PG_PROT) | PG_RW;
343 	/*
344 	 * Enable copy-back caching of data pages
345 	 */
346 	if (mmutype == MMU_68040)
347 		protopte |= PG_CCB;
348 	while (pte < epte) {
349 		*pte++ = protopte;
350 		protopte += PAGE_SIZE;
351 	}
352 
353 #define	PTE2VA(pte)	m68k_ptob(pte - PA2VA(kptpa, pt_entry_t *))
354 
355 	protopte = IOBase | PG_RW | PG_CI | PG_V;
356 	IOBase = PTE2VA(pte);
357 	epte = &pte[IIOMAPSIZE];
358 	while (pte < epte) {
359 		*pte++ = protopte;
360 		protopte += PAGE_SIZE;
361 	}
362 
363 	protopte = (pt_entry_t)ROMBase | PG_RO | PG_V;
364 	ROMBase = (void *)PTE2VA(pte);
365 	epte = &pte[ROMMAPSIZE];
366 	while (pte < epte) {
367 		*pte++ = protopte;
368 		protopte += PAGE_SIZE;
369 	}
370 
371 	if (vidlen) {
372 		protopte = m68k_trunc_page(mac68k_video.mv_phys) |
373 		    PG_RW | PG_V | PG_CI;
374 		newvideoaddr = PTE2VA(pte)
375 		    + m68k_page_offset(mac68k_video.mv_phys);
376 		epte = &pte[VIDMAPSIZE];
377 		while (pte < epte) {
378 			*pte++ = protopte;
379 			protopte += PAGE_SIZE;
380 		}
381 	}
382 	virtual_avail = PTE2VA(pte);
383 
384 	/*
385 	 * Calculate important exported kernel virtual addresses
386 	 */
387 	/*
388 	 * Sysseg: base of kernel segment table
389 	 */
390 	Sysseg = PA2VA(kstpa, st_entry_t *);
391 	/*
392 	 * Sysptmap: base of kernel page table map
393 	 */
394 	Sysptmap = PA2VA(kptmpa, pt_entry_t *);
395 	/*
396 	 * Sysmap: kernel page table (as mapped through Sysptmap)
397 	 * Allocated at the end of KVA space.
398 	 */
399 	Sysmap = (pt_entry_t *)m68k_ptob((NPTEPG - 1) * NPTEPG);
400 
401 	/*
402 	 * Setup u-area for process 0.
403 	 */
404 	/*
405 	 * Zero the u-area.
406 	 * NOTE: `pte' and `epte' aren't PTEs here.
407 	 */
408 	pte = PA2VA(p0upa, u_int *);
409 	epte = (u_int *)(PA2VA(p0upa, u_int) + USPACE);
410 	while (pte < epte)
411 		*pte++ = 0;
412 	/*
413 	 * Remember the u-area address so it can be loaded in the
414 	 * proc struct p_addr field later.
415 	 */
416 	proc0paddr = PA2VA(p0upa, char *);
417 
418 	/*
419 	 * VM data structures are now initialized, set up data for
420 	 * the pmap module.
421 	 *
422 	 * Note about avail_end: msgbuf is initialized just after
423 	 * avail_end in machdep.c.  Since the last page is used
424 	 * for rebooting the system (code is copied there and
425 	 * excution continues from copied code before the MMU
426 	 * is disabled), the msgbuf will get trounced between
427 	 * reboots if it's placed in the last physical page.
428 	 * To work around this, we move avail_end back one more
429 	 * page so the msgbuf can be preserved.
430 	 */
431 	avail_next = avail_start = m68k_round_page(nextpa);
432 	avail_remaining = 0;
433 	avail_range = -1;
434 	for (i = 0; i < numranges; i++) {
435 		if (low[i] <= avail_next && avail_next < high[i]) {
436 			avail_range = i;
437 			avail_remaining = high[i] - avail_next;
438 		} else if (avail_range != -1) {
439 			avail_remaining += (high[i] - low[i]);
440 		}
441 	}
442 	physmem = m68k_btop(avail_remaining + nextpa - firstpa);
443 
444 	maxaddr = high[numranges - 1] - m68k_ptob(1);
445 	high[numranges - 1] -= (m68k_round_page(MSGBUFSIZE) + m68k_ptob(1));
446 	avail_end = high[numranges - 1];
447 	mem_size = m68k_ptob(physmem);
448 	virtual_end = VM_MAX_KERNEL_ADDRESS;
449 
450 	/*
451 	 * Initialize protection array.
452 	 * XXX don't use a switch statement, it might produce an
453 	 * absolute "jmp" table.
454 	 */
455 	{
456 		u_int *kp;
457 
458 		kp = (u_int *)&protection_codes;
459 		kp[VM_PROT_NONE|VM_PROT_NONE|VM_PROT_NONE] = 0;
460 		kp[VM_PROT_READ|VM_PROT_NONE|VM_PROT_NONE] = PG_RO;
461 		kp[VM_PROT_READ|VM_PROT_NONE|VM_PROT_EXECUTE] = PG_RO;
462 		kp[VM_PROT_NONE|VM_PROT_NONE|VM_PROT_EXECUTE] = PG_RO;
463 		kp[VM_PROT_NONE|VM_PROT_WRITE|VM_PROT_NONE] = PG_RW;
464 		kp[VM_PROT_NONE|VM_PROT_WRITE|VM_PROT_EXECUTE] = PG_RW;
465 		kp[VM_PROT_READ|VM_PROT_WRITE|VM_PROT_NONE] = PG_RW;
466 		kp[VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE] = PG_RW;
467 	}
468 
469 	/*
470 	 * Kernel page/segment table allocated above,
471 	 * just initialize pointers.
472 	 */
473 	{
474 		struct pmap *kpm = kernel_pmap_ptr;
475 
476 		kpm->pm_stab = Sysseg;
477 		kpm->pm_ptab = Sysmap;
478 		simple_lock_init(&kpm->pm_lock);
479 		kpm->pm_count = 1;
480 		kpm->pm_stpa = (st_entry_t *)kstpa;
481 		/*
482 		 * For the 040 we also initialize the free level 2
483 		 * descriptor mask noting that we have used:
484 		 *	0:		level 1 table
485 		 *	1 to `num':	map page tables
486 		 *	MAXKL2SIZE-1:	maps kptmpa
487 		 */
488 		if (mmutype == MMU_68040) {
489 			int num;
490 
491 			kpm->pm_stfree = ~l2tobm(0);
492 			num = roundup(nptpages * (NPTEPG / SG4_LEV3SIZE),
493 				      SG4_LEV2SIZE) / SG4_LEV2SIZE;
494 			while (num)
495 				kpm->pm_stfree &= ~l2tobm(num--);
496 			kpm->pm_stfree &= ~l2tobm(MAXKL2SIZE-1);
497 			for (num = MAXKL2SIZE;
498 			     num < sizeof(kpm->pm_stfree)*NBBY;
499 			     num++)
500 				kpm->pm_stfree &= ~l2tobm(num);
501 		}
502 	}
503 
504 	/*
505 	 * Allocate some fixed, special purpose kernel virtual addresses
506 	 */
507 	{
508 		vaddr_t va = virtual_avail;
509 
510 		CADDR1 = (void *)va;
511 		va += PAGE_SIZE;
512 		CADDR2 = (void *)va;
513 		va += PAGE_SIZE;
514 		vmmap = (void *)va;
515 		va += PAGE_SIZE;
516 		msgbufaddr = (void *)va;
517 		va += m68k_round_page(MSGBUFSIZE);
518 		virtual_avail = va;
519 	}
520 }
521 
522 void
523 bootstrap_mac68k(int tc)
524 {
525 #if NZSC > 0
526 	extern void zs_init(void);
527 #endif
528 	extern int *esym;
529 	paddr_t nextpa;
530 	void *oldROMBase;
531 
532 	if (mac68k_machine.do_graybars)
533 		printf("Bootstrapping NetBSD/mac68k.\n");
534 
535 	oldROMBase = ROMBase;
536 	mac68k_video.mv_phys = mac68k_video.mv_kvaddr;
537 
538 	if (((tc & 0x80000000) && (mmutype == MMU_68030)) ||
539 	    ((tc & 0x8000) && (mmutype == MMU_68040))) {
540 		if (mac68k_machine.do_graybars)
541 			printf("Getting mapping from MMU.\n");
542 		(void) get_mapping();
543 		if (mac68k_machine.do_graybars)
544 			printf("Done.\n");
545 	} else {
546 		/* MMU not enabled.  Fake up ranges. */
547 		numranges = 1;
548 		low[0] = 0;
549 		high[0] = mac68k_machine.mach_memsize * (1024 * 1024);
550 		if (mac68k_machine.do_graybars)
551 			printf("Faked range to byte 0x%lx.\n", high[0]);
552 	}
553 	nextpa = load_addr + m68k_round_page(esym);
554 
555 	if (mac68k_machine.do_graybars)
556 		printf("Bootstrapping the pmap system.\n");
557 
558 	pmap_bootstrap(nextpa, load_addr);
559 
560 	if (mac68k_machine.do_graybars)
561 		printf("Pmap bootstrapped.\n");
562 
563 	if (!vidlen)
564 		panic("Don't know how to relocate video!");
565 
566 	if (mac68k_machine.do_graybars)
567 		printf("Moving ROMBase from %p to %p.\n", oldROMBase, ROMBase);
568 
569 	mrg_fixupROMBase(oldROMBase, ROMBase);
570 
571 	if (mac68k_machine.do_graybars)
572 		printf("Video address 0x%p -> 0x%p.\n",
573 		    (void *)mac68k_video.mv_kvaddr, (void *)newvideoaddr);
574 
575 	mac68k_set_io_offsets(IOBase);
576 
577 	/*
578 	 * If the serial ports are going (for console or 'echo'), then
579 	 * we need to make sure the IO change gets propagated properly.
580 	 * This resets the base addresses for the 8530 (serial) driver.
581 	 *
582 	 * WARNING!!! No printfs() (etc) BETWEEN zs_init() and the end
583 	 * of this function (where we start using the MMU, so the new
584 	 * address is correct.
585 	 */
586 #if NZSC > 0
587 	if (zsinited != 0)
588 		zs_init();
589 #endif
590 
591 	mac68k_video.mv_kvaddr = newvideoaddr;
592 }
593