1 /*	$NetBSD: pmap_bootstrap.c,v 1.4 2001/01/12 16:19:18 tsutsui 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. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the University of
22  *	California, Berkeley and its contributors.
23  * 4. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  *
39  *	@(#)pmap_bootstrap.c	8.1 (Berkeley) 6/10/93
40  */
41 /*
42  *	news68k/pmap_bootstrap.c - from hp300 and mvme68k
43  */
44 
45 #include <sys/param.h>
46 
47 #include <machine/cpu.h>
48 #include <machine/pte.h>
49 
50 #include <uvm/uvm_extern.h>
51 
52 #define RELOC(v, t)	*((t*)((u_int)&(v) + firstpa))
53 
54 extern char *etext;
55 extern int Sysptsize;
56 extern char *extiobase, *proc0paddr;
57 extern char *cache_ctl, *cache_clr;
58 extern st_entry_t *Sysseg;
59 extern pt_entry_t *Sysptmap, *Sysmap;
60 
61 extern int maxmem, physmem;
62 extern paddr_t avail_start, avail_end;
63 extern vaddr_t virtual_avail, virtual_end;
64 extern vsize_t mem_size;
65 extern int protection_codes[];
66 extern int pmap_aliasmask;
67 
68 void	pmap_bootstrap __P((paddr_t, paddr_t));
69 
70 /*
71  * Special purpose kernel virtual addresses, used for mapping
72  * physical pages for a variety of temporary or permanent purposes:
73  *
74  *	CADDR1, CADDR2:	pmap zero/copy operations
75  *	vmmap:		/dev/mem, crash dumps, parity error checking
76  *	msgbufaddr:	kernel message buffer
77  */
78 caddr_t		CADDR1, CADDR2, vmmap;
79 extern caddr_t	msgbufaddr;
80 
81 /*
82  * Bootstrap the VM system.
83  *
84  * Called with MMU off so we must relocate all global references by `firstpa'
85  * (don't call any functions here!)  `nextpa' is the first available physical
86  * memory address.  Returns an updated first PA reflecting the memory we
87  * have allocated.  MMU is still off when we return.
88  *
89  * XXX assumes sizeof(u_int) == sizeof(pt_entry_t)
90  * XXX a PIC compiler would make this much easier.
91  */
92 void
93 pmap_bootstrap(nextpa, firstpa)
94 	paddr_t nextpa;
95 	paddr_t firstpa;
96 {
97 	paddr_t kstpa, kptpa, iiopa, eiopa, kptmpa, p0upa;
98 	u_int nptpages, kstsize;
99 	st_entry_t protoste, *ste;
100 	pt_entry_t protopte, *pte, *epte;
101 	u_int iiomapsize, eiomapsize;
102 
103 	/*
104 	 * Calculate important physical addresses:
105 	 *
106 	 *	kstpa		kernel segment table	1 page (!040)
107 	 *						N pages (040)
108 	 *
109 	 *	kptpa		statically allocated
110 	 *			kernel PT pages		Sysptsize+ pages
111 	 *
112 	 *	iiopa		internal IO space
113 	 *			PT pages		iiomapsize pages
114 	 *
115 	 *	eiopa		external IO space
116 	 *			PT pages		eiomapsize pages
117 	 *
118 	 * [ Sysptsize is the number of pages of PT, IIOMAPSIZE and
119 	 *   EIOMAPSIZE are the number of PTEs, hence we need to round
120 	 *   the total to a page boundary with IO maps at the end. ]
121 	 *
122 	 *	kptmpa		kernel PT map		1 page
123 	 *
124 	 *	p0upa		proc 0 u-area		UPAGES pages
125 	 *
126 	 * The KVA corresponding to any of these PAs is:
127 	 *	(PA - firstpa + KERNBASE).
128 	 */
129 
130 	/*
131 	 * XXX now we are using tt0 register to map IIO.
132 	 */
133 	iiomapsize = m68k_btop(RELOC(intiotop_phys, u_int) -
134 			       RELOC(intiobase_phys, u_int));
135 	eiomapsize = m68k_btop(RELOC(extiotop_phys, u_int) -
136 			       RELOC(extiobase_phys, u_int));
137 
138 #ifdef M68040
139 	if (RELOC(mmutype, int) == MMU_68040)
140 		kstsize = MAXKL2SIZE / (NPTEPG/SG4_LEV2SIZE);
141 	else
142 		kstsize = 1;
143 #else
144 	kstsize = 1;
145 #endif
146 	kstpa = nextpa;
147 	nextpa += kstsize * NBPG;
148 	kptpa = nextpa;
149 	nptpages = RELOC(Sysptsize, int) +
150 		(iiomapsize + eiomapsize + NPTEPG - 1) / NPTEPG;
151 	nextpa += nptpages * NBPG;
152 	eiopa = nextpa - eiomapsize * sizeof(pt_entry_t);
153 	iiopa = eiopa - iiomapsize * sizeof(pt_entry_t);
154 	kptmpa = nextpa;
155 	nextpa += NBPG;
156 	p0upa = nextpa;
157 	nextpa += USPACE;
158 
159 	/*
160 	 * Clear all PTEs to zero
161 	 */
162 #if 1
163 	for (pte = (pt_entry_t *)kstpa; pte < (pt_entry_t *)nextpa; pte++)
164 		*pte = 0;
165 #endif
166 
167 	/*
168 	 * Initialize segment table and kernel page table map.
169 	 *
170 	 * On 68030s and earlier MMUs the two are identical except for
171 	 * the valid bits so both are initialized with essentially the
172 	 * same values.  On the 68040, which has a mandatory 3-level
173 	 * structure, the segment table holds the level 1 table and part
174 	 * (or all) of the level 2 table and hence is considerably
175 	 * different.  Here the first level consists of 128 descriptors
176 	 * (512 bytes) each mapping 32mb of address space.  Each of these
177 	 * points to blocks of 128 second level descriptors (512 bytes)
178 	 * each mapping 256kb.  Note that there may be additional "segment
179 	 * table" pages depending on how large MAXKL2SIZE is.
180 	 *
181 	 * Portions of the last segment of KVA space (0xFFF00000 -
182 	 * 0xFFFFFFFF) are mapped for a couple of purposes.  0xFFF00000
183 	 * for UPAGES is used for mapping the current process u-area
184 	 * (u + kernel stack).  The very last page (0xFFFFF000) is mapped
185 	 * to the last physical page of RAM to give us a region in which
186 	 * PA == VA.  We use the first part of this page for enabling
187 	 * and disabling mapping.  The last part of this page also contains
188 	 * info left by the boot ROM.
189 	 *
190 	 * XXX cramming two levels of mapping into the single "segment"
191 	 * table on the 68040 is intended as a temporary hack to get things
192 	 * working.  The 224mb of address space that this allows will most
193 	 * likely be insufficient in the future (at least for the kernel).
194 	 */
195 #ifdef M68040
196 	if (RELOC(mmutype, int) == MMU_68040) {
197 		int num;
198 
199 		/*
200 		 * First invalidate the entire "segment table" pages
201 		 * (levels 1 and 2 have the same "invalid" value).
202 		 */
203 		pte = (u_int *)kstpa;
204 		epte = &pte[kstsize * NPTEPG];
205 		while (pte < epte)
206 			*pte++ = SG_NV;
207 		/*
208 		 * Initialize level 2 descriptors (which immediately
209 		 * follow the level 1 table).  We need:
210 		 *	NPTEPG / SG4_LEV3SIZE
211 		 * level 2 descriptors to map each of the nptpages+1
212 		 * pages of PTEs.  Note that we set the "used" bit
213 		 * now to save the HW the expense of doing it.
214 		 */
215 		num = (nptpages + 1) * (NPTEPG / SG4_LEV3SIZE);
216 		pte = &((u_int *)kstpa)[SG4_LEV1SIZE];
217 		epte = &pte[num];
218 		protoste = kptpa | SG_U | SG_RW | SG_V;
219 		while (pte < epte) {
220 			*pte++ = protoste;
221 			protoste += (SG4_LEV3SIZE * sizeof(st_entry_t));
222 		}
223 		/*
224 		 * Initialize level 1 descriptors.  We need:
225 		 *	roundup(num, SG4_LEV2SIZE) / SG4_LEV2SIZE
226 		 * level 1 descriptors to map the `num' level 2's.
227 		 */
228 		pte = (u_int *)kstpa;
229 		epte = &pte[roundup(num, SG4_LEV2SIZE) / SG4_LEV2SIZE];
230 		protoste = (u_int)&pte[SG4_LEV1SIZE] | SG_U | SG_RW | SG_V;
231 		while (pte < epte) {
232 			*pte++ = protoste;
233 			protoste += (SG4_LEV2SIZE * sizeof(st_entry_t));
234 		}
235 		/*
236 		 * Initialize the final level 1 descriptor to map the last
237 		 * block of level 2 descriptors.
238 		 */
239 		ste = &((u_int *)kstpa)[SG4_LEV1SIZE-1];
240 		pte = &((u_int *)kstpa)[kstsize*NPTEPG - SG4_LEV2SIZE];
241 		*ste = (u_int)pte | SG_U | SG_RW | SG_V;
242 		/*
243 		 * Initialize Sysptmap
244 		 */
245 		pte = (u_int *)kptmpa;
246 		epte = &pte[nptpages+1];
247 		protopte = kptpa | PG_RW | PG_CI | PG_V;
248 		while (pte < epte) {
249 			*pte++ = protopte;
250 			protopte += NBPG;
251 		}
252 		/*
253 		 * Invalidate all but the last remaining entry.
254 		 */
255 		epte = &((u_int *)kptmpa)[NPTEPG];
256 		while (pte < epte) {
257 			*pte++ = PG_NV;
258 		}
259 	} else
260 #endif
261 	{
262 		/*
263 		 * Map the page table pages in both the HW segment table
264 		 * and the software Sysptmap.  Note that Sysptmap is also
265 		 * considered a PT page hence the +1.
266 		 */
267 		ste = (u_int *)kstpa;
268 		pte = (u_int *)kptmpa;
269 		epte = &pte[nptpages+1];
270 		protoste = kptpa | SG_RW | SG_V;
271 		protopte = kptpa | PG_RW | PG_CI | PG_V;
272 		while (pte < epte) {
273 			*ste++ = protoste;
274 			*pte++ = protopte;
275 			protoste += NBPG;
276 			protopte += NBPG;
277 		}
278 		/*
279 		 * Invalidate all but the last remaining entries in both.
280 		 */
281 		epte = &((u_int *)kptmpa)[NPTEPG];
282 		while (pte < epte) {
283 			*ste++ = SG_NV;
284 			*pte++ = PG_NV;
285 		}
286 	}
287 	/*
288 	 * Initialize kernel page table.
289 	 * Start by invalidating the `nptpages' that we have allocated.
290 	 */
291 	pte = (u_int *)kptpa;
292 	epte = &pte[nptpages * NPTEPG];
293 	while (pte < epte)
294 		*pte++ = PG_NV;
295 
296 	/*
297 	 * Validate PTEs for kernel text (RO).
298 	 */
299 	pte = &((u_int *)kptpa)[m68k_btop(KERNBASE)];
300 	epte = &pte[m68k_btop(m68k_trunc_page(&etext))];
301 	protopte = firstpa | PG_RO | PG_V;
302 	while (pte < epte) {
303 		*pte++ = protopte;
304 		protopte += NBPG;
305 	}
306 	/*
307 	 * Validate PTEs for kernel data/bss, dynamic data allocated
308 	 * by us so far (nextpa - firstpa bytes), and pages for proc0
309 	 * u-area and page table allocated below (RW).
310 	 */
311 	epte = &((u_int *)kptpa)[m68k_btop(nextpa - firstpa)];
312 	protopte = (protopte & ~PG_PROT) | PG_RW;
313 	/*
314 	 * Enable copy-back caching of data pages
315 	 */
316 #ifdef M68040
317 	if (RELOC(mmutype, int) == MMU_68040)
318 		protopte |= PG_CCB;
319 #endif
320 	while (pte < epte) {
321 		*pte++ = protopte;
322 		protopte += NBPG;
323 	}
324 	/*
325 	 * Finally, validate the internal IO space PTEs (RW+CI).
326 	 */
327 	pte = (u_int *)iiopa;
328 	epte = (u_int *)eiopa;
329 	protopte = RELOC(intiobase_phys, u_int) | PG_RW | PG_CI | PG_V;
330 	while (pte < epte) {
331 		*pte++ = protopte;
332 		protopte += NBPG;
333 	}
334 
335 	/*
336 	 * Calculate important exported kernel virtual addresses
337 	 */
338 	/*
339 	 * Sysseg: base of kernel segment table
340 	 */
341 	RELOC(Sysseg, st_entry_t *) =
342 		(st_entry_t *)(kstpa - firstpa);
343 	/*
344 	 * Sysptmap: base of kernel page table map
345 	 */
346 	RELOC(Sysptmap, pt_entry_t *) =
347 		(pt_entry_t *)(kptmpa - firstpa);
348 	/*
349 	 * Sysmap: kernel page table (as mapped through Sysptmap)
350 	 * Immediately follows `nptpages' of static kernel page table.
351 	 */
352 	RELOC(Sysmap, pt_entry_t *) =
353 		(pt_entry_t *)m68k_ptob(nptpages * NPTEPG);
354 	/*
355 	 * intiobase, intiolimit: base and end of internal IO space.
356 	 */
357 	RELOC(intiobase, char *) =
358 		(char *)m68k_ptob(nptpages*NPTEPG - (iiomapsize + eiomapsize));
359 	RELOC(intiolimit, char *) =
360 		(char *)m68k_ptob(nptpages*NPTEPG - eiomapsize);
361 	/*
362 	 * extiobase: base of external IO space.
363 	 * eiomapsize pages at the end of the static kernel page table.
364 	 */
365 	RELOC(extiobase, char *) =
366 		(char *)m68k_ptob(nptpages*NPTEPG - eiomapsize);
367 
368 	/*
369 	 * Setup u-area for process 0.
370 	 */
371 	/*
372 	 * Zero the u-area.
373 	 * NOTE: `pte' and `epte' aren't PTEs here.
374 	 */
375 	pte = (u_int *)p0upa;
376 	epte = (u_int *)(p0upa + USPACE);
377 	while (pte < epte)
378 		*pte++ = 0;
379 	/*
380 	 * Remember the u-area address so it can be loaded in the
381 	 * proc struct p_addr field later.
382 	 */
383 	RELOC(proc0paddr, char *) = (char *)(p0upa - firstpa);
384 
385 	/*
386 	 * VM data structures are now initialized, set up data for
387 	 * the pmap module.
388 	 *
389 	 * Note about avail_end: msgbuf is initialized just after
390 	 * avail_end in machdep.c.
391 	 */
392 	RELOC(avail_start, paddr_t) = nextpa;
393 	RELOC(avail_end, paddr_t) = m68k_ptob(RELOC(maxmem, int)) -
394 	    (m68k_round_page(MSGBUFSIZE));
395 	RELOC(mem_size, vsize_t) = m68k_ptob(RELOC(physmem, int));
396 
397 	RELOC(virtual_avail, vaddr_t) =
398 		VM_MIN_KERNEL_ADDRESS + (vaddr_t)(nextpa - firstpa);
399 	RELOC(virtual_end, vaddr_t) = VM_MAX_KERNEL_ADDRESS;
400 
401 #if 0
402 	/*
403 	 * Determine VA aliasing distance if any
404 	 *
405 	 * XXX Are there any models which have VAC?
406 	 */
407 	if (RELOC(ectype, int) == EC_VIRT) {
408 		RELOC(pmap_aliasmask, int) = 0x3fff;	/* 16k */
409 	}
410 #endif
411 #ifdef news1700
412 	if (RELOC(systype, int) == NEWS1700) {
413 		RELOC(cache_ctl, char *) = 0xe1300000 - INTIOBASE1700 +
414 					  RELOC(intiobase, char *);
415 		RELOC(cache_clr, char *) = 0xe1900000 - INTIOBASE1700 +
416 					  RELOC(intiobase, char *);
417 	}
418 #endif
419 
420 	/*
421 	 * Initialize protection array.
422 	 * XXX don't use a switch statement, it might produce an
423 	 * absolute "jmp" table.
424 	 */
425 	{
426 		int *kp;
427 
428 		kp = &RELOC(protection_codes, int);
429 		kp[VM_PROT_NONE|VM_PROT_NONE|VM_PROT_NONE] = 0;
430 		kp[VM_PROT_READ|VM_PROT_NONE|VM_PROT_NONE] = PG_RO;
431 		kp[VM_PROT_READ|VM_PROT_NONE|VM_PROT_EXECUTE] = PG_RO;
432 		kp[VM_PROT_NONE|VM_PROT_NONE|VM_PROT_EXECUTE] = PG_RO;
433 		kp[VM_PROT_NONE|VM_PROT_WRITE|VM_PROT_NONE] = PG_RW;
434 		kp[VM_PROT_NONE|VM_PROT_WRITE|VM_PROT_EXECUTE] = PG_RW;
435 		kp[VM_PROT_READ|VM_PROT_WRITE|VM_PROT_NONE] = PG_RW;
436 		kp[VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE] = PG_RW;
437 	}
438 
439 	/*
440 	 * Kernel page/segment table allocated above,
441 	 * just initialize pointers.
442 	 */
443 	{
444 		struct pmap *kpm = &RELOC(kernel_pmap_store, struct pmap);
445 
446 		kpm->pm_stab = RELOC(Sysseg, st_entry_t *);
447 		kpm->pm_ptab = RELOC(Sysmap, pt_entry_t *);
448 		simple_lock_init(&kpm->pm_lock);
449 		kpm->pm_count = 1;
450 		kpm->pm_stpa = (st_entry_t *)kstpa;
451 		/*
452 		 * For the 040 we also initialize the free level 2
453 		 * descriptor mask noting that we have used:
454 		 *	0:		level 1 table
455 		 *	1 to `num':	map page tables
456 		 *	MAXKL2SIZE-1:	maps last-page page table
457 		 */
458 #ifdef M68040
459 		if (RELOC(mmutype, int) == MMU_68040) {
460 			int num;
461 
462 			kpm->pm_stfree = ~l2tobm(0);
463 			num = roundup((nptpages + 1) * (NPTEPG / SG4_LEV3SIZE),
464 				      SG4_LEV2SIZE) / SG4_LEV2SIZE;
465 			while (num)
466 				kpm->pm_stfree &= ~l2tobm(num--);
467 			kpm->pm_stfree &= ~l2tobm(MAXKL2SIZE-1);
468 			for (num = MAXKL2SIZE;
469 			     num < sizeof(kpm->pm_stfree)*NBBY;
470 			     num++)
471 				kpm->pm_stfree &= ~l2tobm(num);
472 		}
473 #endif
474 	}
475 
476 	/*
477 	 * Allocate some fixed, special purpose kernel virtual addresses
478 	 */
479 	{
480 		vaddr_t va = RELOC(virtual_avail, vaddr_t);
481 
482 		RELOC(CADDR1, caddr_t) = (caddr_t)va;
483 		va += NBPG;
484 		RELOC(CADDR2, caddr_t) = (caddr_t)va;
485 		va += NBPG;
486 		RELOC(vmmap, caddr_t) = (caddr_t)va;
487 		va += NBPG;
488 		RELOC(msgbufaddr, caddr_t) = (caddr_t)va;
489 		va += m68k_round_page(MSGBUFSIZE);
490 		RELOC(virtual_avail, vaddr_t) = va;
491 	}
492 }
493