xref: /netbsd-src/sys/arch/amiga/amiga/amiga_init.c (revision 219483d9ac8b4beb5e84ee761625f29ac41f0242)
1 /*	$NetBSD: amiga_init.c,v 1.133 2024/01/09 07:28:25 thorpej Exp $	*/
2 
3 /*
4  * Copyright (c) 1994 Michael L. Hitch
5  * Copyright (c) 1993 Markus Wild
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *      This product includes software developed by Markus Wild.
19  * 4. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include "opt_amigaccgrf.h"
35 #include "opt_p5ppc68kboard.h"
36 #include "opt_devreload.h"
37 #include "opt_m68k_arch.h"
38 #include "z3rambd.h"
39 #include "ser.h"
40 
41 #include <sys/cdefs.h>
42 __KERNEL_RCSID(0, "$NetBSD: amiga_init.c,v 1.133 2024/01/09 07:28:25 thorpej Exp $");
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/ioctl.h>
47 #include <sys/select.h>
48 #include <sys/tty.h>
49 #include <sys/buf.h>
50 #include <sys/msgbuf.h>
51 #include <sys/mbuf.h>
52 #include <sys/protosw.h>
53 #include <sys/domain.h>
54 #include <sys/dkbad.h>
55 #include <sys/reboot.h>
56 #include <sys/exec.h>
57 
58 #include <dev/mm.h>
59 #include <uvm/uvm_extern.h>
60 
61 #include <machine/pte.h>
62 #include <machine/cpu.h>
63 #include <amiga/amiga/cc.h>
64 #include <amiga/amiga/cia.h>
65 #include <amiga/amiga/custom.h>
66 #include <amiga/amiga/cfdev.h>
67 #include <amiga/amiga/drcustom.h>
68 #include <amiga/amiga/gayle.h>
69 #include <amiga/amiga/memlist.h>
70 #include <amiga/dev/zbusvar.h>
71 #include <amiga/dev/z3rambdvar.h>
72 
73 #define RELOC(v, t)	*((t*)((u_int)&(v) + loadbase))
74 
75 extern u_int	lowram;
76 extern u_int	Umap;
77 extern u_long boot_partition;
78 extern vaddr_t	m68k_uptbase;
79 
80 #ifdef P5PPC68KBOARD
81 extern int	p5ppc;
82 #endif
83 
84 extern char *esym;
85 
86 #ifdef GRF_AGA
87 extern u_long aga_enable;
88 #endif
89 
90 #if NSER > 0
91 extern int serconsole;
92 #endif
93 
94 extern u_long noncontig_enable;
95 
96 /*
97  * some addresses used in locore
98  */
99 vaddr_t INTREQRaddr;
100 vaddr_t INTREQWaddr;
101 
102 /*
103  * these are used by the extended spl?() macros.
104  */
105 volatile unsigned short *amiga_intena_read, *amiga_intena_write;
106 
107 vaddr_t CHIPMEMADDR;
108 vaddr_t chipmem_start;
109 vaddr_t chipmem_end;
110 
111 vaddr_t z2mem_start;		/* XXX */
112 static vaddr_t z2mem_end;		/* XXX */
113 int use_z2_mem = 1;			/* XXX */
114 
115 u_long boot_fphystart, boot_fphysize, boot_cphysize;
116 static u_int start_c_fphystart;
117 static u_int start_c_pstart;
118 
119 static u_long boot_flags;
120 
121 struct boot_memlist *memlist;
122 
123 struct cfdev *cfdev;
124 int ncfdev;
125 
126 u_long scsi_nosync;
127 int shift_nosync;
128 
129 void  start_c(int, u_int, u_int, u_int, char *, u_int, u_long, u_long, u_int);
130 void rollcolor(int);
131 #ifdef DEVRELOAD
132 static int kernel_image_magic_size(void);
133 static void kernel_image_magic_copy(u_char *);
134 int kernel_reload_write(struct uio *);
135 extern void kernel_reload(char *, u_long, u_long, u_long, u_long,
136 	u_long, u_long, u_long, u_long, u_long, u_long);
137 #endif
138 extern void etext(void);
139 void start_c_finish(void);
140 
141 void *
chipmem_steal(long amount)142 chipmem_steal(long amount)
143 {
144 	/*
145 	 * steal from top of chipmem, so we don't collide with
146 	 * the kernel loaded into chipmem in the not-yet-mapped state.
147 	 */
148 	vaddr_t p = chipmem_end - amount;
149 	if (p & 1)
150 		p = p - 1;
151 	chipmem_end = p;
152 	if(chipmem_start > chipmem_end)
153 		panic("not enough chip memory");
154 	return((void *)p);
155 }
156 
157 /*
158  * XXX
159  * used by certain drivers currently to allocate zorro II memory
160  * for bounce buffers, if use_z2_mem is NULL, chipmem will be
161  * returned instead.
162  * XXX
163  */
164 void *
alloc_z2mem(long amount)165 alloc_z2mem(long amount)
166 {
167 	if (use_z2_mem && z2mem_end && (z2mem_end - amount) >= z2mem_start) {
168 		z2mem_end -= amount;
169 		return ((void *)z2mem_end);
170 	}
171 	return (alloc_chipmem(amount));
172 }
173 
174 
175 /*
176  * this is the C-level entry function, it's called from locore.s.
177  * Preconditions:
178  *	Interrupts are disabled
179  *	PA may not be == VA, so we may have to relocate addresses
180  *		before enabling the MMU
181  * 	Exec is no longer available (because we're loaded all over
182  *		low memory, no ExecBase is available anymore)
183  *
184  * It's purpose is:
185  *	Do the things that are done in locore.s in the hp300 version,
186  *		this includes allocation of kernel maps and enabling the MMU.
187  *
188  * Some of the code in here is `stolen' from Amiga MACH, and was
189  * written by Bryan Ford and Niklas Hallqvist.
190  *
191  * Very crude 68040 support by Michael L. Hitch.
192  *
193  */
194 
195 int kernel_copyback = 1;
196 
197 __attribute__ ((no_instrument_function))
198 void
start_c(int id,u_int fphystart,u_int fphysize,u_int cphysize,char * esym_addr,u_int flags,u_long inh_sync,u_long boot_part,u_int loadbase)199 start_c(int id, u_int fphystart, u_int fphysize, u_int cphysize,
200 	char *esym_addr, u_int flags, u_long inh_sync, u_long boot_part,
201 	u_int loadbase)
202 {
203 	extern char end[];
204 	struct cfdev *cd;
205 	paddr_t pstart, pend;
206 	vaddr_t vstart, vend;
207 	psize_t avail;
208 	paddr_t ptpa;
209 	psize_t ptsize;
210 	u_int ptextra, kstsize;
211 	paddr_t Sysptmap_pa;
212 	register st_entry_t sg_proto, *sg;
213 #if defined(M68040) || defined(M68060)
214 	register st_entry_t *esg;
215 #endif
216 	register pt_entry_t pg_proto, *pg, *epg;
217 	vaddr_t end_loaded;
218 	u_int ncd;
219 #if defined(M68040) || defined(M68060)
220 	u_int i, nl1desc, nl2desc;
221 #endif
222 	vaddr_t kva;
223 	struct boot_memlist *ml;
224 
225 #ifdef DEBUG_KERNEL_START
226 	/* XXX this only is valid if Altais is in slot 0 */
227 	volatile u_int8_t *altaiscolpt = (u_int8_t *)0x200003c8;
228 	volatile u_int8_t *altaiscol = (u_int8_t *)0x200003c9;
229 #endif
230 
231 #ifdef DEBUG_KERNEL_START
232 	if ((id>>24)==0x7D) {
233 		*altaiscolpt = 0;
234 		*altaiscol = 40;
235 		*altaiscol = 0;
236 		*altaiscol = 0;
237 	} else
238 ((volatile struct Custom *)0xdff000)->color[0] = 0xa00;		/* RED */
239 #endif
240 
241 #ifdef LIMITMEM
242 	if (fphysize > LIMITMEM*1024*1024)
243 		fphysize = LIMITMEM*1024*1024;
244 #endif
245 
246 	RELOC(boot_fphystart, u_long) = fphystart;
247 	RELOC(boot_fphysize, u_long) = fphysize;
248 	RELOC(boot_cphysize, u_long) = cphysize;
249 
250 	RELOC(machineid, int) = id;
251 	RELOC(chipmem_end, vaddr_t) = cphysize;
252 	RELOC(esym, char *) = esym_addr;
253 	RELOC(boot_flags, u_long) = flags;
254 	RELOC(boot_partition, u_long) = boot_part;
255 #ifdef GRF_AGA
256 	if (flags & 1)
257 		RELOC(aga_enable, u_long) |= 1;
258 #endif
259 	if (flags & (3 << 1))
260 		RELOC(noncontig_enable, u_long) = (flags >> 1) & 3;
261 #if NSER > 0
262 	if (flags & (1 << 3))
263 		RELOC(serconsole, int) = 0;
264 #endif
265 
266 	RELOC(scsi_nosync, u_long) = inh_sync;
267 
268 	/*
269 	 * the kernel ends at end(), plus the cfdev and memlist structures
270 	 * we placed there in the loader.  Correct for this now.  Also,
271 	 * account for kernel symbols if they are present.
272 	 */
273 	if (esym_addr == NULL)
274 		end_loaded = (vaddr_t)&end;
275 	else
276 		end_loaded = (vaddr_t)esym_addr;
277 	RELOC(ncfdev, int) = *(int *)(&RELOC(*(u_int *)end_loaded, u_int));
278 	RELOC(cfdev, struct cfdev *) = (struct cfdev *) ((int)end_loaded + 4);
279 	end_loaded += 4 + RELOC(ncfdev, int) * sizeof(struct cfdev);
280 
281 	RELOC(memlist, struct boot_memlist *) =
282 	    (struct boot_memlist *)end_loaded;
283 	ml = &RELOC(*(struct boot_memlist *)end_loaded, struct boot_memlist);
284 	end_loaded = (vaddr_t)&((RELOC(memlist, struct boot_memlist *))->
285 	    m_seg[ml->m_nseg]);
286 
287 	/*
288 	 * Get ZorroII (16-bit) memory if there is any and it's not where the
289 	 * kernel is loaded.
290 	 */
291 	if (ml->m_nseg > 0 && ml->m_nseg < 16 && RELOC(use_z2_mem, int)) {
292 		struct boot_memseg *sp, *esp;
293 
294 		sp = ml->m_seg;
295 		esp = sp + ml->m_nseg;
296 		for (; sp < esp; sp++) {
297 			if ((sp->ms_attrib & (MEMF_FAST | MEMF_24BITDMA))
298 			    != (MEMF_FAST|MEMF_24BITDMA))
299 				continue;
300 			if (sp->ms_start == fphystart)
301 				continue;
302 			RELOC(z2mem_end, paddr_t) =
303 			    sp->ms_start + sp->ms_size;
304 			RELOC(z2mem_start, paddr_t) =
305 			    RELOC(z2mem_end, paddr_t) - MAXPHYS *
306 			    RELOC(use_z2_mem, int) * 7;
307 			RELOC(NZTWOMEMPG, u_int) =
308 			    (RELOC(z2mem_end, paddr_t) -
309 			    RELOC(z2mem_start, paddr_t)) / PAGE_SIZE;
310 			if ((RELOC(z2mem_end, paddr_t) -
311 			    RELOC(z2mem_start, paddr_t)) > sp->ms_size) {
312 				RELOC(NZTWOMEMPG, u_int) = sp->ms_size /
313 				    PAGE_SIZE;
314 				RELOC(z2mem_start, paddr_t) =
315 				    RELOC(z2mem_end, paddr_t) - sp->ms_size;
316 			}
317 			break;
318 		}
319 	}
320 
321 	/*
322 	 * Scan ConfigDev list and get size of Zorro I/O boards that are
323 	 * outside the Zorro II I/O area.
324 	 */
325 	for (RELOC(ZBUSAVAIL, u_int) = 0, cd =
326 	    &RELOC(*RELOC(cfdev, struct cfdev *),struct cfdev),
327 	    ncd = RELOC(ncfdev, int); ncd > 0; ncd--, cd++) {
328 		int bd_type = cd->rom.type & (ERT_TYPEMASK | ERTF_MEMLIST);
329 
330 		/*
331 		 * Hack to support p5bus and p5pb on CyberStorm Mk-III / PPC
332 		 * and Blizzard PPC. XXX: this hack should only be active if
333 		 * non-autoconfiguring CyberVision PPC or BlizzardVision PPC
334 		 * was found.
335 		 */
336 		if (cd->rom.manid == 8512 &&
337 		    (cd->rom.prodid == 100 || cd->rom.prodid == 110))
338 			RELOC(ZBUSAVAIL, u_int) += m68k_round_page(0x1400000);
339 #if NZ3RAMBD > 0
340 		if (z3rambd_match_id(cd->rom.manid, cd->rom.prodid) > 0)
341 		{
342 			/* XXX: remove board from memlist */
343 		} else
344 #endif
345 		if (bd_type != ERT_ZORROIII &&
346 		    (bd_type != ERT_ZORROII || isztwopa(cd->addr)))
347 			continue;	/* It's not Z2 or Z3 I/O board */
348 		/*
349 		 *  Hack to adjust board size for Zorro III boards that
350 		 *  do not specify an extended size or subsize.  This is
351 		 *  specifically for the GVP Spectrum and hopefully won't
352 		 *  break with other boards that configure like this.
353 		 */
354 		if (bd_type == ERT_ZORROIII &&
355 		    !(cd->rom.flags & ERFF_EXTENDED) &&
356 		    (cd->rom.flags & ERT_Z3_SSMASK) == 0)
357 			cd->size = 0x10000 <<
358 			    ((cd->rom.type - 1) & ERT_MEMMASK);
359 
360 		RELOC(ZBUSAVAIL, u_int) += m68k_round_page(cd->size);
361 	}
362 
363 	/*
364 	 * assume KVA_MIN == 0.  We subtract the kernel code (and
365 	 * the configdev's and memlists) from the virtual and
366 	 * physical starts and ends.
367 	 */
368 	vend   = fphysize;
369 	avail  = vend;
370 	vstart = end_loaded;
371 	vstart = m68k_round_page(vstart);
372 	pstart = (paddr_t)vstart + fphystart;
373 	pend   = vend   + fphystart;
374 	avail -= vstart;
375 
376 	/*
377 	 * save KVA of lwp0 u-area and allocate it.
378 	 */
379 	RELOC(lwp0uarea, vaddr_t) = vstart;
380 	pstart += USPACE;
381 	vstart += USPACE;
382 	avail -= USPACE;
383 
384 #if defined(M68040) || defined(M68060)
385 	if (RELOC(mmutype, int) == MMU_68040)
386 		kstsize = MAXKL2SIZE / (NPTEPG/SG4_LEV2SIZE);
387 	else
388 #endif
389 		kstsize = 1;
390 
391 	/*
392 	 * allocate the kernel segment table
393 	 */
394 	RELOC(Sysseg_pa, u_int) = pstart;
395 	RELOC(Sysseg, u_int) = vstart;
396 	vstart += PAGE_SIZE * kstsize;
397 	pstart += PAGE_SIZE * kstsize;
398 	avail -= PAGE_SIZE * kstsize;
399 
400 	/*
401 	 * allocate kernel page table map
402 	 */
403 	RELOC(Sysptmap, u_int) = vstart;
404 	Sysptmap_pa = pstart;
405 	vstart += PAGE_SIZE;
406 	pstart += PAGE_SIZE;
407 	avail -= PAGE_SIZE;
408 
409 	/*
410 	 * allocate initial page table pages
411 	 */
412 	ptpa = pstart;
413 #ifdef DRACO
414 	if ((id>>24)==0x7D) {
415 		ptextra = NDRCCPG
416 		    + RELOC(NZTWOMEMPG, u_int)
417 		    + btoc(RELOC(ZBUSAVAIL, u_int));
418 	} else
419 #endif
420 	ptextra = NCHIPMEMPG + NCIAPG + NZTWOROMPG + RELOC(NZTWOMEMPG, u_int) +
421 	    btoc(RELOC(ZBUSAVAIL, u_int)) + NPCMCIAPG;
422 
423 	ptsize = (RELOC(Sysptsize, u_int) +
424 	    howmany(ptextra, NPTEPG)) << PGSHIFT;
425 
426 	vstart += ptsize;
427 	pstart += ptsize;
428 	avail -= ptsize;
429 
430 	/*
431 	 * Sysmap is now placed at the end of Supervisor virtual address space.
432 	 */
433 	RELOC(Sysmap, u_int *) = (u_int *)SYSMAP_VA;
434 
435 	/*
436 	 * initialize segment table and page table map
437 	 */
438 #if defined(M68040) || defined(M68060)
439 	if (RELOC(mmutype, int) == MMU_68040) {
440 		/*
441 		 * First invalidate the entire "segment table" pages
442 		 * (levels 1 and 2 have the same "invalid" values).
443 		 */
444 		sg = (st_entry_t *)RELOC(Sysseg_pa, u_int);
445 		esg = &sg[kstsize * NPTEPG];
446 		while (sg < esg)
447 			*sg++ = SG_NV;
448 		/*
449 		 * Initialize level 2 descriptors (which immediately
450 		 * follow the level 1 table).  We need:
451 		 *	NPTEPG / SG4_LEV3SIZE
452 		 * level 2 descriptors to map each of the nptpages
453 		 * pages of PTEs.  Note that we set the "used" bit
454 		 * now to save the HW the expense of doing it.
455 		 */
456 		nl2desc = (ptsize >> PGSHIFT) * (NPTEPG / SG4_LEV3SIZE);
457 		sg = (st_entry_t *)RELOC(Sysseg_pa, u_int);
458 		sg = &sg[SG4_LEV1SIZE];
459 		esg = &sg[nl2desc];
460 		sg_proto = ptpa | SG_U | SG_RW | SG_V;
461 		while (sg < esg) {
462 			*sg++ = sg_proto;
463 			sg_proto += (SG4_LEV3SIZE * sizeof (st_entry_t));
464 		}
465 
466 		/*
467 		 * Initialize level 1 descriptors.  We need:
468 		 *	howmany(nl2desc, SG4_LEV2SIZE)
469 		 * level 1 descriptors to map the 'nl2desc' level 2's.
470 		 */
471 		nl1desc = howmany(nl2desc, SG4_LEV2SIZE);
472 		sg = (st_entry_t *)RELOC(Sysseg_pa, u_int);
473 		esg = &sg[nl1desc];
474 		sg_proto = (paddr_t)&sg[SG4_LEV1SIZE] | SG_U | SG_RW | SG_V;
475 		while (sg < esg) {
476 			*sg++ = sg_proto;
477 			sg_proto += (SG4_LEV2SIZE * sizeof(st_entry_t));
478 		}
479 
480 		/* Sysmap is last entry in level 1 */
481 		sg = (st_entry_t *)RELOC(Sysseg_pa, u_int);
482 		sg = &sg[SG4_LEV1SIZE - 1];
483 		*sg = sg_proto;
484 
485 		/*
486 		 * Kernel segment table at end of next level 2 table
487 		 */
488 		i = SG4_LEV1SIZE + (nl1desc * SG4_LEV2SIZE);
489 		sg = (st_entry_t *)RELOC(Sysseg_pa, u_int);
490 		sg = &sg[i + SG4_LEV2SIZE - (NPTEPG / SG4_LEV3SIZE)];
491 		esg = &sg[NPTEPG / SG4_LEV3SIZE];
492 		sg_proto = Sysptmap_pa | SG_U | SG_RW | SG_V;
493 		while (sg < esg) {
494 			*sg++ = sg_proto;
495 			sg_proto += (SG4_LEV3SIZE * sizeof (st_entry_t));
496 		}
497 
498 		/* Include additional level 2 table for Sysmap in protostfree */
499 		RELOC(protostfree, u_int) =
500 		    (~0 << (1 + nl1desc + 1)) /* & ~(~0 << MAXKL2SIZE) */;
501 
502 		/*
503 		 * Initialize Sysptmap
504 		 */
505 		pg = (pt_entry_t *)Sysptmap_pa;
506 		epg = &pg[ptsize >> PGSHIFT];
507 		pg_proto = ptpa | PG_RW | PG_CI | PG_V;
508 		while (pg < epg) {
509 			*pg++ = pg_proto;
510 			pg_proto += PAGE_SIZE;
511 		}
512 		/*
513 		 * Invalidate rest of Sysptmap page
514 		 */
515 		epg = (pt_entry_t *)(Sysptmap_pa + PAGE_SIZE - sizeof(st_entry_t));
516 		while (pg < epg)
517 			*pg++ = SG_NV;
518 		pg = (pt_entry_t *)Sysptmap_pa;
519 		pg = &pg[SYSMAP_VA >> SEGSHIFT];
520 		*pg = Sysptmap_pa | PG_RW | PG_CI | PG_V;
521 	} else
522 #endif /* M68040 */
523 	{
524 		/*
525 		 * Map the page table pages in both the HW segment table
526 		 * and the software Sysptmap.
527 		 */
528 		sg = (st_entry_t *)RELOC(Sysseg_pa, u_int);
529 		pg = (pt_entry_t *)Sysptmap_pa;
530 		epg = &pg[ptsize >> PGSHIFT];
531 		sg_proto = ptpa | SG_RW | SG_V;
532 		pg_proto = ptpa | PG_RW | PG_CI | PG_V;
533 		while (pg < epg) {
534 			*sg++ = sg_proto;
535 			*pg++ = pg_proto;
536 			sg_proto += PAGE_SIZE;
537 			pg_proto += PAGE_SIZE;
538 		}
539 		/*
540 		 * invalidate the remainder of each table
541 		 */
542 		epg = (pt_entry_t *)Sysptmap_pa;
543 		epg = &epg[TIA_SIZE];
544 		while (pg < epg) {
545 			*sg++ = SG_NV;
546 			*pg++ = PG_NV;
547 		}
548 		sg = (st_entry_t *)RELOC(Sysseg_pa, u_int);
549 		sg = &sg[SYSMAP_VA >> SEGSHIFT];
550 		pg = (pt_entry_t *)Sysptmap_pa;
551 		pg = &pg[SYSMAP_VA >> SEGSHIFT];
552 		*sg = Sysptmap_pa | SG_RW | SG_V;
553 		*pg = Sysptmap_pa | PG_RW | PG_CI | PG_V;
554 		/* XXX zero out rest of page? */
555 	}
556 
557 	/*
558 	 * initialize kernel page table page(s) (assume load at VA 0)
559 	 */
560 	pg_proto = fphystart | PG_RO | PG_V;	/* text pages are RO */
561 	pg       = (pt_entry_t *)ptpa;
562 	*pg++ = PG_NV;				/* Make page 0 invalid */
563 	pg_proto += PAGE_SIZE;
564 	for (kva = PAGE_SIZE; kva < (vaddr_t)etext;
565 	     kva += PAGE_SIZE, pg_proto += PAGE_SIZE)
566 		*pg++ = pg_proto;
567 
568 	/*
569 	 * data, bss and dynamic tables are read/write
570 	 */
571 	pg_proto = (pg_proto & PG_FRAME) | PG_RW | PG_V;
572 
573 #if defined(M68040) || defined(M68060)
574 	/*
575 	 * Map the kernel segment table cache invalidated for 68040/68060.
576 	 * (for the 68040 not strictly necessary, but recommended by Motorola;
577 	 *  for the 68060 mandatory)
578 	 */
579 	if (RELOC(mmutype, int) == MMU_68040) {
580 
581 		if (RELOC(kernel_copyback, int))
582 			pg_proto |= PG_CCB;
583 
584 		/*
585 		 * ASSUME: segment table and statically allocated page tables
586 		 * of the kernel are contiguously allocated, start at
587 		 * Sysseg and end at the current value of vstart.
588 		 */
589 		for (; kva < RELOC(Sysseg, u_int);
590 		     kva += PAGE_SIZE, pg_proto += PAGE_SIZE)
591 			*pg++ = pg_proto;
592 
593 		pg_proto = (pg_proto & ~PG_CCB) | PG_CI;
594 		for (; kva < vstart; kva += PAGE_SIZE, pg_proto += PAGE_SIZE)
595 			*pg++ = pg_proto;
596 
597 		pg_proto = (pg_proto & ~PG_CI);
598 		if (RELOC(kernel_copyback, int))
599 			pg_proto |= PG_CCB;
600 	}
601 #endif
602 	/*
603 	 * go till end of data allocated so far
604 	 * plus lwp0 u-area (to be allocated)
605 	 */
606 	for (; kva < vstart; kva += PAGE_SIZE, pg_proto += PAGE_SIZE)
607 		*pg++ = pg_proto;
608 	/*
609 	 * invalidate remainder of kernel PT
610 	 */
611 	while (pg < (pt_entry_t *) (ptpa + ptsize))
612 		*pg++ = PG_NV;
613 
614 	/*
615 	 * validate internal IO PTEs following current vstart
616 	 */
617 	pg = &((u_int *)ptpa)[vstart >> PGSHIFT];
618 #ifdef DRACO
619 	if ((id >> 24) == 0x7D) {
620 		RELOC(DRCCADDR, u_int) = vstart;
621 		RELOC(CIAADDR, vaddr_t) =
622 		    RELOC(DRCCADDR, u_int) + DRCIAPG * PAGE_SIZE;
623 		if (RELOC(z2mem_end, vaddr_t) == 0)
624 			RELOC(ZBUSADDR, vaddr_t) =
625 			   RELOC(DRCCADDR, u_int) + NDRCCPG * PAGE_SIZE;
626 		pg_proto = DRCCBASE | PG_RW | PG_CI | PG_V;
627 		while (pg_proto < DRZ2BASE) {
628 			*pg++ = pg_proto;
629 			pg_proto += DRCCSTRIDE;
630 			vstart += PAGE_SIZE;
631 		}
632 
633 		/* NCR 53C710 chip */
634 		*pg++ = DRSCSIBASE | PG_RW | PG_CI | PG_V;
635 		vstart += PAGE_SIZE;
636 
637 #ifdef DEBUG_KERNEL_START
638 		/*
639 		 * early rollcolor Altais mapping
640 		 * XXX (only works if in slot 0)
641 		 */
642 		*pg++ = 0x20000000 | PG_RW | PG_CI | PG_V;
643 		vstart += PAGE_SIZE;
644 #endif
645 	} else
646 #endif
647 	{
648 		RELOC(CHIPMEMADDR, vaddr_t) = vstart;
649 		pg_proto = CHIPMEMBASE | PG_RW | PG_CI | PG_V;
650 						/* CI needed here?? */
651 		while (pg_proto < CHIPMEMTOP) {
652 			*pg++     = pg_proto;
653 			pg_proto += PAGE_SIZE;
654 			vstart   += PAGE_SIZE;
655 		}
656 	}
657 	if (RELOC(z2mem_end, paddr_t)) {			/* XXX */
658 		RELOC(ZTWOMEMADDR, vaddr_t) = vstart;
659 		RELOC(ZBUSADDR, vaddr_t) = RELOC(ZTWOMEMADDR, vaddr_t) +
660 		    RELOC(NZTWOMEMPG, u_int) * PAGE_SIZE;
661 		pg_proto = RELOC(z2mem_start, paddr_t) |	/* XXX */
662 		    PG_RW | PG_V;				/* XXX */
663 		while (pg_proto < RELOC(z2mem_end, paddr_t)) { /* XXX */
664 			*pg++ = pg_proto;			/* XXX */
665 			pg_proto += PAGE_SIZE;			/* XXX */
666 			vstart   += PAGE_SIZE;
667 		}						/* XXX */
668 	}							/* XXX */
669 #ifdef DRACO
670 	if ((id >> 24) != 0x7D)
671 #endif
672 	{
673 		RELOC(CIAADDR, vaddr_t) = vstart;
674 		pg_proto = CIABASE | PG_RW | PG_CI | PG_V;
675 		while (pg_proto < CIATOP) {
676 			*pg++     = pg_proto;
677 			pg_proto += PAGE_SIZE;
678 			vstart   += PAGE_SIZE;
679 		}
680 		RELOC(ZTWOROMADDR, vaddr_t) = vstart;
681 		pg_proto  = ZTWOROMBASE | PG_RW | PG_CI | PG_V;
682 		while (pg_proto < ZTWOROMTOP) {
683 			*pg++     = pg_proto;
684 			pg_proto += PAGE_SIZE;
685 			vstart   += PAGE_SIZE;
686 		}
687 		RELOC(ZBUSADDR, vaddr_t) = vstart;
688 		/* not on 8k boundary :-( */
689 		RELOC(CIAADDR, vaddr_t) += PAGE_SIZE/2;
690 		RELOC(CUSTOMADDR, vaddr_t)  =
691 		    RELOC(ZTWOROMADDR, vaddr_t) - ZTWOROMBASE + CUSTOMBASE;
692 	}
693 
694 	/*
695 	 *[ following page tables MAY be allocated to ZORRO3 space,
696 	 * but they're then later mapped in autoconf.c ]
697 	 */
698 	vstart += RELOC(ZBUSAVAIL, u_int);
699 
700 	/*
701 	 * init mem sizes
702 	 */
703 	RELOC(maxmem, u_int)  = pend >> PGSHIFT;
704 	RELOC(lowram, u_int)  = fphystart;
705 	RELOC(physmem, u_int) = fphysize >> PGSHIFT;
706 
707 	RELOC(virtual_avail, u_int) = vstart;
708 
709 	/*
710 	 * Put user page tables starting at next 16MB boundary, to make kernel
711 	 * dumps more readable, with guaranteed 16MB of.
712 	 * XXX 16 MB instead of 256 MB should be enough, but...
713 	 * we need to fix the fastmem loading first. (see comment at line 375)
714 	 */
715 	RELOC(m68k_uptbase, vaddr_t) =
716 	    roundup(vstart + 0x10000000, 0x10000000);
717 
718 	/*
719 	 * set this before copying the kernel, so the variable is updated in
720 	 * the `real' place too. protorp[0] is already preset to the
721 	 * CRP setting.
722 	 */
723 	RELOC(protorp[1], u_int) = RELOC(Sysseg_pa, u_int);
724 
725 	RELOC(start_c_fphystart, u_int) = fphystart;
726 	RELOC(start_c_pstart, u_int) = pstart;
727 
728 	/*
729 	 * copy over the kernel (and all now initialized variables)
730 	 * to fastram.  DONT use bcopy(), this beast is much larger
731 	 * than 128k !
732 	 */
733 	if (loadbase == 0) {
734 		register paddr_t *lp, *le, *fp;
735 
736 		lp = (paddr_t *)0;
737 		le = (paddr_t *)end_loaded;
738 		fp = (paddr_t *)fphystart;
739 		while (lp < le)
740 			*fp++ = *lp++;
741 	}
742 
743 #ifdef DEBUG_KERNEL_START
744 	if ((id>>24)==0x7D) {
745 		*altaiscolpt = 0;
746 		*altaiscol = 40;
747 		*altaiscol = 40;
748 		*altaiscol = 0;
749 	} else
750 ((volatile struct Custom *)0xdff000)->color[0] = 0xAA0;		/* YELLOW */
751 #endif
752 	/*
753 	 * prepare to enable the MMU
754 	 */
755 #if defined(M68040) || defined(M68060)
756 	if (RELOC(mmutype, int) == MMU_68040) {
757 		if (id & AMIGA_68060) {
758 			/* do i need to clear the branch cache? */
759 			__asm volatile (	".word 0x4e7a,0x0002;"
760 					"orl #0x400000,%%d0;"
761 					".word 0x4e7b,0x0002" : : : "d0");
762 		}
763 
764 		/*
765 		 * movel Sysseg_pa,%a0;
766 		 * movec %a0,%srp;
767 		 */
768 
769 		__asm volatile ("movel %0,%%a0; .word 0x4e7b,0x8807"
770 		    : : "a" (RELOC(Sysseg_pa, u_int)) : "a0");
771 
772 #ifdef DEBUG_KERNEL_START
773 		if ((id>>24)==0x7D) {
774 			*altaiscolpt = 0;
775 			*altaiscol = 40;
776 			*altaiscol = 33;
777 			*altaiscol = 0;
778 		} else
779 ((volatile struct Custom *)0xdff000)->color[0] = 0xA70;		/* ORANGE */
780 #endif
781 	} else
782 #endif
783 	{
784 		/*
785 		 * setup and load SRP (see pmap.h)
786 		 */
787 		__asm volatile ("pmove %0@,%%srp":: "a" (&RELOC(protorp, u_int)));
788 	}
789 }
790 
791 void
start_c_finish(void)792 start_c_finish(void)
793 {
794 	extern u_int32_t delaydivisor;
795 #ifdef	P5PPC68KBOARD
796         struct cfdev *cdp, *ecdp;
797 #endif
798 
799 #ifdef DEBUG_KERNEL_START
800 #ifdef DRACO
801 	if ((id >> 24) == 0x7D) { /* mapping on, is_draco() is valid */
802 		int i;
803 		/* XXX experimental Altais register mapping only */
804 		altaiscolpt = (volatile u_int8_t *)(DRCCADDR+PAGE_SIZE*9+0x3c8);
805 		altaiscol = altaiscolpt + 1;
806 		for (i=0; i<140000; i++) {
807 			*altaiscolpt = 0;
808 			*altaiscol = 0;
809 			*altaiscol = 40;
810 			*altaiscol = 0;
811 		}
812 	} else
813 #endif
814 ((volatile struct Custom *)CUSTOMADDR)->color[0] = 0x0a0;	/* GREEN */
815 #endif
816 
817 	pmap_bootstrap(start_c_pstart, start_c_fphystart);
818 	pmap_bootstrap_finalize();
819 
820 	/*
821 	 * to make life easier in locore.s, set these addresses explicitly
822 	 */
823 	CIAAbase = CIAADDR + 0x1001;	/* CIA-A at odd addresses ! */
824 	CIABbase = CIAADDR;
825 	CUSTOMbase = CUSTOMADDR;
826 #ifdef DRACO
827 	if (is_draco()) {
828 		draco_intena = (volatile u_int8_t *)DRCCADDR+1;
829 		draco_intpen = draco_intena + PAGE_SIZE;
830 		draco_intfrc = draco_intpen + PAGE_SIZE;
831 		draco_misc = draco_intfrc + PAGE_SIZE;
832 		draco_ioct = (struct drioct *)(DRCCADDR + DRIOCTLPG*PAGE_SIZE);
833 	} else
834 #endif
835 	{
836 		INTREQRaddr = (vaddr_t)&custom.intreqr;
837 		INTREQWaddr = (vaddr_t)&custom.intreq;
838 	}
839 	/*
840 	 * Get our chip memory allocation system working
841 	 */
842 	chipmem_start += CHIPMEMADDR;
843 	chipmem_end   += CHIPMEMADDR;
844 
845 	/* XXX is: this MUST NOT BE DONE before the pmap_bootstrap() call */
846 	if (z2mem_end) {
847 		z2mem_end = ZTWOMEMADDR + NZTWOMEMPG * PAGE_SIZE;
848 		z2mem_start = ZTWOMEMADDR;
849 	}
850 
851 	/*
852 	 * disable all interrupts but enable allow them to be enabled
853 	 * by specific driver code (global int enable bit)
854 	 */
855 #ifdef DRACO
856 	if (is_draco()) {
857 		/* XXX to be done. For now, just: */
858 		*draco_intena = 0;
859 		*draco_intpen = 0;
860 		*draco_intfrc = 0;
861 		ciaa.icr = 0x7f;			/* and keyboard */
862 		ciab.icr = 0x7f;			/* and again */
863 
864 		draco_ioct->io_control &=
865 		    ~(DRCNTRL_KBDINTENA|DRCNTRL_FDCINTENA); /* and another */
866 
867 		draco_ioct->io_status2 &=
868 		    ~(DRSTAT2_PARIRQENA|DRSTAT2_TMRINTENA); /* some more */
869 
870 		*(volatile u_int8_t *)(DRCCADDR + 1 +
871 		    DRSUPIOPG*PAGE_SIZE + 4*(0x3F8 + 1)) = 0; /* and com0 */
872 
873 		*(volatile u_int8_t *)(DRCCADDR + 1 +
874 		    DRSUPIOPG*PAGE_SIZE + 4*(0x2F8 + 1)) = 0; /* and com1 */
875 
876 		draco_ioct->io_control |= DRCNTRL_WDOGDIS; /* stop Fido */
877 		*draco_misc &= ~1/*DRMISC_FASTZ2*/;
878 
879 	} else
880 #endif
881 	{
882 		custom.intena = 0x7fff;			/* disable ints */
883 		custom.intena = INTF_SETCLR | INTF_INTEN;
884 							/* but allow them */
885 		custom.intreq = 0x7fff;			/* clear any current */
886 		ciaa.icr = 0x7f;			/* and keyboard */
887 		ciab.icr = 0x7f;			/* and again */
888 
889 		/*
890 		 * remember address of read and write intena register for use
891 		 * by extended spl?() macros.
892 		 */
893 		amiga_intena_read  = &custom.intenar;
894 		amiga_intena_write = &custom.intena;
895 	}
896 
897 	/*
898 	 * This is needed for 3000's with superkick ROM's. Bit 7 of
899 	 * 0xde0002 enables the ROM if set. If this isn't set the machine
900 	 * has to be powercycled in order for it to boot again. ICKA! RFH
901 	 */
902 	if (is_a3000()) {
903 		volatile unsigned char *a3000_magic_reset;
904 
905 		a3000_magic_reset = (volatile unsigned char *)ztwomap(0xde0002);
906 
907 		/* Turn SuperKick ROM (V36) back on */
908 		*a3000_magic_reset |= 0x80;
909 	}
910 
911 #ifdef	P5PPC68KBOARD
912 	/*
913 	 * Are we an P5 PPC/68K board? install different reset
914 	 * routine.
915 	 */
916 
917         for (cdp = cfdev, ecdp = &cfdev[ncfdev]; cdp < ecdp; cdp++) {
918 		if (cdp->rom.manid == 8512 &&
919 		    (cdp->rom.prodid == 100 || cdp->rom.prodid == 110)) {
920 		    		p5ppc = 1;
921 				break;
922 			}
923         }
924 #endif
925 	/*
926 	 * preliminary delay divisor value
927 	 */
928 
929 	if (machineid & AMIGA_68060)
930 		delaydivisor = (1024 * 1) / 80;	/* 80 MHz 68060 w. BTC */
931 
932 	else if (machineid & AMIGA_68040)
933 		delaydivisor = (1024 * 3) / 40;	/* 40 MHz 68040 */
934 
935 	else if (machineid & AMIGA_68030)
936 		delaydivisor = (1024 * 8) / 50;	/* 50 MHz 68030 */
937 
938 	else
939 		delaydivisor = (1024 * 8) / 33; /* 33 MHz 68020 */
940 }
941 
942 void
rollcolor(int color)943 rollcolor(int color)
944 {
945 	int s, i;
946 
947 	s = splhigh();
948 	/*
949 	 * need to adjust count -
950 	 * too slow when cache off, too fast when cache on
951 	 */
952 	for (i = 0; i < 400000; i++)
953 		((volatile struct Custom *)CUSTOMbase)->color[0] = color;
954 	splx(s);
955 }
956 
957 #ifdef DEVRELOAD
958 /*
959  * Kernel reloading code
960  */
961 
962 static struct exec kernel_exec;
963 static u_char *kernel_image;
964 static u_long kernel_text_size, kernel_load_ofs;
965 static u_long kernel_load_phase;
966 static u_long kernel_load_endseg;
967 static u_long kernel_symbol_size, kernel_symbol_esym;
968 
969 /* This supports the /dev/reload device, major 2, minor 20,
970    hooked into mem.c.  Author: Bryan Ford.  */
971 
972 /*
973  * This is called below to find out how much magic storage
974  * will be needed after a kernel image to be reloaded.
975  */
976 static int
kernel_image_magic_size(void)977 kernel_image_magic_size(void)
978 {
979 	int sz;
980 
981 	/* 4 + cfdev's + Mem_Seg's + 4 */
982 	sz = 8 + ncfdev * sizeof(struct cfdev)
983 	    + memlist->m_nseg * sizeof(struct boot_memseg);
984 	return(sz);
985 }
986 
987 /* This actually copies the magic information.  */
988 static void
kernel_image_magic_copy(u_char * dest)989 kernel_image_magic_copy(u_char *dest)
990 {
991 	*((int*)dest) = ncfdev;
992 	dest += 4;
993 	memcpy(dest, cfdev, ncfdev * sizeof(struct cfdev)
994 	    + memlist->m_nseg * sizeof(struct boot_memseg) + 4);
995 }
996 
997 #undef AOUT_LDPGSZ
998 #define AOUT_LDPGSZ 8192 /* XXX ??? */
999 
1000 int
kernel_reload_write(struct uio * uio)1001 kernel_reload_write(struct uio *uio)
1002 {
1003 	extern int eclockfreq;
1004 	struct iovec *iov;
1005 	int error, c;
1006 
1007 	iov = uio->uio_iov;
1008 
1009 	if (kernel_image == 0) {
1010 		/*
1011 		 * We have to get at least the whole exec header
1012 		 * in the first write.
1013 		 */
1014 		if (iov->iov_len < sizeof(kernel_exec))
1015 			return ENOEXEC;		/* XXX */
1016 
1017 		/*
1018 		 * Pull in the exec header and check it.
1019 		 */
1020 		if ((error = uiomove((void *)&kernel_exec, sizeof(kernel_exec),
1021 		     uio)) != 0)
1022 			return(error);
1023 		printf("loading kernel %ld+%ld+%ld+%ld\n", kernel_exec.a_text,
1024 		    kernel_exec.a_data, kernel_exec.a_bss,
1025 		    esym == NULL ? 0 : kernel_exec.a_syms);
1026 		/*
1027 		 * Looks good - allocate memory for a kernel image.
1028 		 */
1029 		kernel_text_size = (kernel_exec.a_text
1030 			+ AOUT_LDPGSZ - 1) & (-AOUT_LDPGSZ);
1031 		/*
1032 		 * Estimate space needed for symbol names, since we don't
1033 		 * know how big it really is.
1034 		 */
1035 		if (esym != NULL) {
1036 			kernel_symbol_size = kernel_exec.a_syms;
1037 			kernel_symbol_size += 16 * (kernel_symbol_size / 12);
1038 		}
1039 		/*
1040 		 * XXX - should check that image will fit in CHIP memory
1041 		 * XXX return an error if it doesn't
1042 		 */
1043 		if ((kernel_text_size + kernel_exec.a_data +
1044 		    kernel_exec.a_bss + kernel_symbol_size +
1045 		    kernel_image_magic_size()) > boot_cphysize)
1046 			return (EFBIG);
1047 		kernel_image = malloc(kernel_text_size + kernel_exec.a_data
1048 			+ kernel_exec.a_bss
1049 			+ kernel_symbol_size
1050 			+ kernel_image_magic_size(),
1051 			M_TEMP, M_WAITOK);
1052 		kernel_load_ofs = 0;
1053 		kernel_load_phase = 0;
1054 		kernel_load_endseg = kernel_exec.a_text;
1055 		return(0);
1056 	}
1057 	/*
1058 	 * Continue loading in the kernel image.
1059 	 */
1060 	c = uimin(iov->iov_len, kernel_load_endseg - kernel_load_ofs);
1061 	c = uimin(c, MAXPHYS);
1062 	if ((error = uiomove(kernel_image + kernel_load_ofs, (int)c, uio)) != 0)
1063 		return(error);
1064 	kernel_load_ofs += c;
1065 
1066 	/*
1067 	 * Fun and games to handle loading symbols - the length of the
1068 	 * string table isn't know until after the symbol table has
1069 	 * been loaded.  We have to load the kernel text, data, and
1070 	 * the symbol table, then get the size of the strings.  A
1071 	 * new kernel image is then allocated and the data currently
1072 	 * loaded moved to the new image.  Then continue reading the
1073 	 * string table.  This has problems if there isn't enough
1074 	 * room to allocate space for the two copies of the kernel
1075 	 * image.  So the approach I took is to guess at the size
1076 	 * of the symbol strings.  If the guess is wrong, the symbol
1077 	 * table is ignored.
1078 	 */
1079 
1080 	if (kernel_load_ofs != kernel_load_endseg)
1081 		return(0);
1082 
1083 	switch (kernel_load_phase) {
1084 	case 0:		/* done loading kernel text */
1085 		kernel_load_ofs = kernel_text_size;
1086 		kernel_load_endseg = kernel_load_ofs + kernel_exec.a_data;
1087 		kernel_load_phase = 1;
1088 		break;
1089 	case 1:		/* done loading kernel data */
1090 		for(c = 0; c < kernel_exec.a_bss; c++)
1091 			kernel_image[kernel_load_ofs + c] = 0;
1092 		kernel_load_ofs += kernel_exec.a_bss;
1093 		if (esym) {
1094 			kernel_load_endseg = kernel_load_ofs
1095 			    + kernel_exec.a_syms + 8;
1096 			*((u_long *)(kernel_image + kernel_load_ofs)) =
1097 			    kernel_exec.a_syms;
1098 			kernel_load_ofs += 4;
1099 			kernel_load_phase = 3;
1100 			break;
1101 		}
1102 		/*FALLTHROUGH*/
1103 	case 2:		/* done loading kernel */
1104 
1105 		/*
1106 		 * Put the finishing touches on the kernel image.
1107 		 */
1108 		kernel_image_magic_copy(kernel_image + kernel_load_ofs);
1109 		/*
1110 		 * Start the new kernel with code in locore.s.
1111 		 */
1112 		kernel_reload(kernel_image,
1113 		    kernel_load_ofs + kernel_image_magic_size(),
1114 		    kernel_exec.a_entry, boot_fphystart, boot_fphysize,
1115 		    boot_cphysize, kernel_symbol_esym, eclockfreq,
1116 		    boot_flags, scsi_nosync, boot_partition);
1117 		/*
1118 		 * kernel_reload() now checks to see if the reload_code
1119 		 * is at the same location in the new kernel.
1120 		 * If it isn't, it will return and we will return
1121 		 * an error.
1122 		 */
1123 		free(kernel_image, M_TEMP);
1124 		kernel_image = NULL;
1125 		return (ENODEV);	/* Say operation not supported */
1126 	case 3:		/* done loading kernel symbol table */
1127 		c = *((u_long *)(kernel_image + kernel_load_ofs - 4));
1128 		if (c > 16 * (kernel_exec.a_syms / 12))
1129 			c = 16 * (kernel_exec.a_syms / 12);
1130 		kernel_load_endseg += c - 4;
1131 		kernel_symbol_esym = kernel_load_endseg;
1132 #ifdef notyet
1133 		kernel_image_copy = kernel_image;
1134 		kernel_image = malloc(kernel_load_ofs + c
1135 		    + kernel_image_magic_size(), M_TEMP, M_WAITOK);
1136 		if (kernel_image == NULL)
1137 			panic("kernel_reload failed second malloc");
1138 		for (c = 0; c < kernel_load_ofs; c += MAXPHYS)
1139 			memcpy(kernel_image + c, kernel_image_copy + c,
1140 			    (kernel_load_ofs - c) > MAXPHYS ? MAXPHYS :
1141 			    kernel_load_ofs - c);
1142 #endif
1143 		kernel_load_phase = 2;
1144 	}
1145 	return(0);
1146 }
1147 #endif
1148 
1149 int
mm_md_readwrite(dev_t dev,struct uio * uio)1150 mm_md_readwrite(dev_t dev, struct uio *uio)
1151 {
1152 
1153 	switch (minor(dev)) {
1154 #ifdef DEVRELOAD
1155 	case DEV_RELOAD:
1156 		if (uio->uio_rw == UIO_READ)
1157 			return 0;
1158 		return kernel_reload_write(uio);
1159 #endif
1160 	default:
1161 		return ENXIO;
1162 	}
1163 }
1164