xref: /netbsd-src/sys/arch/powerpc/ibm4xx/pmap.c (revision fd5cb0acea84d278e04e640d37ca2398f894991f)
1 /*	$NetBSD: pmap.c,v 1.31 2005/01/27 12:35:53 simonb Exp $	*/
2 
3 /*
4  * Copyright 2001 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Eduardo Horvath and Simon Burge for Wasabi Systems, Inc.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *      This product includes software developed for the NetBSD Project by
20  *      Wasabi Systems, Inc.
21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22  *    or promote products derived from this software without specific prior
23  *    written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 /*
39  * Copyright (C) 1995, 1996 Wolfgang Solfrank.
40  * Copyright (C) 1995, 1996 TooLs GmbH.
41  * All rights reserved.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 3. All advertising materials mentioning features or use of this software
52  *    must display the following acknowledgement:
53  *	This product includes software developed by TooLs GmbH.
54  * 4. The name of TooLs GmbH may not be used to endorse or promote products
55  *    derived from this software without specific prior written permission.
56  *
57  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
58  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
59  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
60  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
61  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
62  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
63  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
64  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
65  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
66  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
67  */
68 
69 #include <sys/cdefs.h>
70 __KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.31 2005/01/27 12:35:53 simonb Exp $");
71 
72 #include <sys/param.h>
73 #include <sys/malloc.h>
74 #include <sys/proc.h>
75 #include <sys/user.h>
76 #include <sys/queue.h>
77 #include <sys/systm.h>
78 #include <sys/pool.h>
79 #include <sys/device.h>
80 
81 #include <uvm/uvm.h>
82 
83 #include <machine/cpu.h>
84 #include <machine/pcb.h>
85 #include <machine/powerpc.h>
86 
87 #include <powerpc/spr.h>
88 #include <machine/tlb.h>
89 
90 /*
91  * kernmap is an array of PTEs large enough to map in
92  * 4GB.  At 16KB/page it is 256K entries or 2MB.
93  */
94 #define KERNMAP_SIZE	((0xffffffffU/PAGE_SIZE)+1)
95 caddr_t kernmap;
96 
97 #define MINCTX		2
98 #define NUMCTX		256
99 volatile struct pmap *ctxbusy[NUMCTX];
100 
101 #define TLBF_USED	0x1
102 #define	TLBF_REF	0x2
103 #define	TLBF_LOCKED	0x4
104 #define	TLB_LOCKED(i)	(tlb_info[(i)].ti_flags & TLBF_LOCKED)
105 typedef struct tlb_info_s {
106 	char	ti_flags;
107 	char	ti_ctx;		/* TLB_PID assiciated with the entry */
108 	u_int	ti_va;
109 } tlb_info_t;
110 
111 volatile tlb_info_t tlb_info[NTLB];
112 /* We'll use a modified FIFO replacement policy cause it's cheap */
113 volatile int tlbnext = TLB_NRESERVED;
114 
115 u_long dtlb_miss_count = 0;
116 u_long itlb_miss_count = 0;
117 u_long ktlb_miss_count = 0;
118 u_long utlb_miss_count = 0;
119 
120 /* Event counters */
121 struct evcnt tlbmiss_ev = EVCNT_INITIALIZER(EVCNT_TYPE_TRAP,
122 	NULL, "cpu", "tlbmiss");
123 struct evcnt tlbhit_ev = EVCNT_INITIALIZER(EVCNT_TYPE_TRAP,
124 	NULL, "cpu", "tlbhit");
125 struct evcnt tlbflush_ev = EVCNT_INITIALIZER(EVCNT_TYPE_TRAP,
126 	NULL, "cpu", "tlbflush");
127 struct evcnt tlbenter_ev = EVCNT_INITIALIZER(EVCNT_TYPE_TRAP,
128 	NULL, "cpu", "tlbenter");
129 
130 struct pmap kernel_pmap_;
131 
132 int physmem;
133 static int npgs;
134 static u_int nextavail;
135 #ifndef MSGBUFADDR
136 extern paddr_t msgbuf_paddr;
137 #endif
138 
139 static struct mem_region *mem, *avail;
140 
141 /*
142  * This is a cache of referenced/modified bits.
143  * Bits herein are shifted by ATTRSHFT.
144  */
145 static char *pmap_attrib;
146 
147 #define PV_WIRED	0x1
148 #define PV_WIRE(pv)	((pv)->pv_va |= PV_WIRED)
149 #define PV_UNWIRE(pv)	((pv)->pv_va &= ~PV_WIRED)
150 #define PV_ISWIRED(pv)	((pv)->pv_va & PV_WIRED)
151 #define PV_CMPVA(va,pv)	(!(((pv)->pv_va ^ (va)) & (~PV_WIRED)))
152 
153 struct pv_entry {
154 	struct pv_entry *pv_next;	/* Linked list of mappings */
155 	vaddr_t pv_va;			/* virtual address of mapping */
156 	struct pmap *pv_pm;
157 };
158 
159 struct pv_entry *pv_table;
160 static struct pool pv_pool;
161 
162 static int pmap_initialized;
163 
164 static int ctx_flush(int);
165 
166 inline struct pv_entry *pa_to_pv(paddr_t);
167 static inline char *pa_to_attr(paddr_t);
168 
169 static inline volatile u_int *pte_find(struct pmap *, vaddr_t);
170 static inline int pte_enter(struct pmap *, vaddr_t, u_int);
171 
172 static inline int pmap_enter_pv(struct pmap *, vaddr_t, paddr_t, boolean_t);
173 static void pmap_remove_pv(struct pmap *, vaddr_t, paddr_t);
174 
175 
176 inline struct pv_entry *
177 pa_to_pv(paddr_t pa)
178 {
179 	int bank, pg;
180 
181 	bank = vm_physseg_find(atop(pa), &pg);
182 	if (bank == -1)
183 		return NULL;
184 	return &vm_physmem[bank].pmseg.pvent[pg];
185 }
186 
187 static inline char *
188 pa_to_attr(paddr_t pa)
189 {
190 	int bank, pg;
191 
192 	bank = vm_physseg_find(atop(pa), &pg);
193 	if (bank == -1)
194 		return NULL;
195 	return &vm_physmem[bank].pmseg.attrs[pg];
196 }
197 
198 /*
199  * Insert PTE into page table.
200  */
201 int
202 pte_enter(struct pmap *pm, vaddr_t va, u_int pte)
203 {
204 	int seg = STIDX(va);
205 	int ptn = PTIDX(va);
206 	u_int oldpte;
207 
208 	if (!pm->pm_ptbl[seg]) {
209 		/* Don't allocate a page to clear a non-existent mapping. */
210 		if (!pte)
211 			return (0);
212 		/* Allocate a page XXXX this will sleep! */
213 		pm->pm_ptbl[seg] =
214 		    (uint *)uvm_km_zalloc(kernel_map, PAGE_SIZE);
215 	}
216 	oldpte = pm->pm_ptbl[seg][ptn];
217 	pm->pm_ptbl[seg][ptn] = pte;
218 
219 	/* Flush entry. */
220 	ppc4xx_tlb_flush(va, pm->pm_ctx);
221 	if (oldpte != pte) {
222 		if (pte == 0)
223 			pm->pm_stats.resident_count--;
224 		else
225 			pm->pm_stats.resident_count++;
226 	}
227 	return (1);
228 }
229 
230 /*
231  * Get a pointer to a PTE in a page table.
232  */
233 volatile u_int *
234 pte_find(struct pmap *pm, vaddr_t va)
235 {
236 	int seg = STIDX(va);
237 	int ptn = PTIDX(va);
238 
239 	if (pm->pm_ptbl[seg])
240 		return (&pm->pm_ptbl[seg][ptn]);
241 
242 	return (NULL);
243 }
244 
245 /*
246  * This is called during initppc, before the system is really initialized.
247  */
248 void
249 pmap_bootstrap(u_int kernelstart, u_int kernelend)
250 {
251 	struct mem_region *mp, *mp1;
252 	int cnt, i;
253 	u_int s, e, sz;
254 
255 	/*
256 	 * Allocate the kernel page table at the end of
257 	 * kernel space so it's in the locked TTE.
258 	 */
259 	kernmap = (caddr_t)kernelend;
260 
261 	/*
262 	 * Initialize kernel page table.
263 	 */
264 	for (i = 0; i < STSZ; i++) {
265 		pmap_kernel()->pm_ptbl[i] = 0;
266 	}
267 	ctxbusy[0] = ctxbusy[1] = pmap_kernel();
268 
269 	/*
270 	 * Announce page-size to the VM-system
271 	 */
272 	uvmexp.pagesize = NBPG;
273 	uvm_setpagesize();
274 
275 	/*
276 	 * Get memory.
277 	 */
278 	mem_regions(&mem, &avail);
279 	for (mp = mem; mp->size; mp++) {
280 		physmem += btoc(mp->size);
281 		printf("+%lx,",mp->size);
282 	}
283 	printf("\n");
284 	ppc4xx_tlb_init();
285 	/*
286 	 * Count the number of available entries.
287 	 */
288 	for (cnt = 0, mp = avail; mp->size; mp++)
289 		cnt++;
290 
291 	/*
292 	 * Page align all regions.
293 	 * Non-page aligned memory isn't very interesting to us.
294 	 * Also, sort the entries for ascending addresses.
295 	 */
296 	kernelstart &= ~PGOFSET;
297 	kernelend = (kernelend + PGOFSET) & ~PGOFSET;
298 	for (mp = avail; mp->size; mp++) {
299 		s = mp->start;
300 		e = mp->start + mp->size;
301 		printf("%08x-%08x -> ",s,e);
302 		/*
303 		 * Check whether this region holds all of the kernel.
304 		 */
305 		if (s < kernelstart && e > kernelend) {
306 			avail[cnt].start = kernelend;
307 			avail[cnt++].size = e - kernelend;
308 			e = kernelstart;
309 		}
310 		/*
311 		 * Look whether this regions starts within the kernel.
312 		 */
313 		if (s >= kernelstart && s < kernelend) {
314 			if (e <= kernelend)
315 				goto empty;
316 			s = kernelend;
317 		}
318 		/*
319 		 * Now look whether this region ends within the kernel.
320 		 */
321 		if (e > kernelstart && e <= kernelend) {
322 			if (s >= kernelstart)
323 				goto empty;
324 			e = kernelstart;
325 		}
326 		/*
327 		 * Now page align the start and size of the region.
328 		 */
329 		s = round_page(s);
330 		e = trunc_page(e);
331 		if (e < s)
332 			e = s;
333 		sz = e - s;
334 		printf("%08x-%08x = %x\n",s,e,sz);
335 		/*
336 		 * Check whether some memory is left here.
337 		 */
338 		if (sz == 0) {
339 		empty:
340 			memmove(mp, mp + 1,
341 				(cnt - (mp - avail)) * sizeof *mp);
342 			cnt--;
343 			mp--;
344 			continue;
345 		}
346 		/*
347 		 * Do an insertion sort.
348 		 */
349 		npgs += btoc(sz);
350 		for (mp1 = avail; mp1 < mp; mp1++)
351 			if (s < mp1->start)
352 				break;
353 		if (mp1 < mp) {
354 			memmove(mp1 + 1, mp1, (char *)mp - (char *)mp1);
355 			mp1->start = s;
356 			mp1->size = sz;
357 		} else {
358 			mp->start = s;
359 			mp->size = sz;
360 		}
361 	}
362 
363 	/*
364 	 * We cannot do pmap_steal_memory here,
365 	 * since we don't run with translation enabled yet.
366 	 */
367 #ifndef MSGBUFADDR
368 	/*
369 	 * allow for msgbuf
370 	 */
371 	sz = round_page(MSGBUFSIZE);
372 	mp = NULL;
373 	for (mp1 = avail; mp1->size; mp1++)
374 		if (mp1->size >= sz)
375 			mp = mp1;
376 	if (mp == NULL)
377 		panic("not enough memory?");
378 
379 	npgs -= btoc(sz);
380 	msgbuf_paddr = mp->start + mp->size - sz;
381 	mp->size -= sz;
382 	if (mp->size <= 0)
383 		memmove(mp, mp + 1, (cnt - (mp - avail)) * sizeof *mp);
384 #endif
385 
386 	for (mp = avail; mp->size; mp++)
387 		uvm_page_physload(atop(mp->start), atop(mp->start + mp->size),
388 			atop(mp->start), atop(mp->start + mp->size),
389 			VM_FREELIST_DEFAULT);
390 
391 	/*
392 	 * Initialize kernel pmap and hardware.
393 	 */
394 	/* Setup TLB pid allocator so it knows we alreadu using PID 1 */
395 	pmap_kernel()->pm_ctx = KERNEL_PID;
396 	nextavail = avail->start;
397 
398 
399 	evcnt_attach_static(&tlbmiss_ev);
400 	evcnt_attach_static(&tlbhit_ev);
401 	evcnt_attach_static(&tlbflush_ev);
402 	evcnt_attach_static(&tlbenter_ev);
403 }
404 
405 /*
406  * Restrict given range to physical memory
407  *
408  * (Used by /dev/mem)
409  */
410 void
411 pmap_real_memory(paddr_t *start, psize_t *size)
412 {
413 	struct mem_region *mp;
414 
415 	for (mp = mem; mp->size; mp++) {
416 		if (*start + *size > mp->start &&
417 		    *start < mp->start + mp->size) {
418 			if (*start < mp->start) {
419 				*size -= mp->start - *start;
420 				*start = mp->start;
421 			}
422 			if (*start + *size > mp->start + mp->size)
423 				*size = mp->start + mp->size - *start;
424 			return;
425 		}
426 	}
427 	*size = 0;
428 }
429 
430 /*
431  * Initialize anything else for pmap handling.
432  * Called during vm_init().
433  */
434 void
435 pmap_init(void)
436 {
437 	struct pv_entry *pv;
438 	vsize_t sz;
439 	vaddr_t addr;
440 	int i, s;
441 	int bank;
442 	char *attr;
443 
444 	sz = (vsize_t)((sizeof(struct pv_entry) + 1) * npgs);
445 	sz = round_page(sz);
446 	addr = uvm_km_zalloc(kernel_map, sz);
447 	s = splvm();
448 	pv = pv_table = (struct pv_entry *)addr;
449 	for (i = npgs; --i >= 0;)
450 		pv++->pv_pm = NULL;
451 	pmap_attrib = (char *)pv;
452 	memset(pv, 0, npgs);
453 
454 	pv = pv_table;
455 	attr = pmap_attrib;
456 	for (bank = 0; bank < vm_nphysseg; bank++) {
457 		sz = vm_physmem[bank].end - vm_physmem[bank].start;
458 		vm_physmem[bank].pmseg.pvent = pv;
459 		vm_physmem[bank].pmseg.attrs = attr;
460 		pv += sz;
461 		attr += sz;
462 	}
463 
464 	pmap_initialized = 1;
465 	splx(s);
466 
467 	/* Setup a pool for additional pvlist structures */
468 	pool_init(&pv_pool, sizeof(struct pv_entry), 0, 0, 0, "pv_entry", NULL);
469 }
470 
471 /*
472  * How much virtual space is available to the kernel?
473  */
474 void
475 pmap_virtual_space(vaddr_t *start, vaddr_t *end)
476 {
477 
478 #if 0
479 	/*
480 	 * Reserve one segment for kernel virtual memory
481 	 */
482 	*start = (vaddr_t)(KERNEL_SR << ADDR_SR_SHFT);
483 	*end = *start + SEGMENT_LENGTH;
484 #else
485 	*start = (vaddr_t) VM_MIN_KERNEL_ADDRESS;
486 	*end = (vaddr_t) VM_MAX_KERNEL_ADDRESS;
487 #endif
488 }
489 
490 #ifdef PMAP_GROWKERNEL
491 /*
492  * Preallocate kernel page tables to a specified VA.
493  * This simply loops through the first TTE for each
494  * page table from the beginning of the kernel pmap,
495  * reads the entry, and if the result is
496  * zero (either invalid entry or no page table) it stores
497  * a zero there, populating page tables in the process.
498  * This is not the most efficient technique but i don't
499  * expect it to be called that often.
500  */
501 extern struct vm_page *vm_page_alloc1 __P((void));
502 extern void vm_page_free1 __P((struct vm_page *));
503 
504 vaddr_t kbreak = VM_MIN_KERNEL_ADDRESS;
505 
506 vaddr_t
507 pmap_growkernel(vaddr_t maxkvaddr)
508 {
509 	int s;
510 	int seg;
511 	paddr_t pg;
512 	struct pmap *pm = pmap_kernel();
513 
514 	s = splvm();
515 
516 	/* Align with the start of a page table */
517 	for (kbreak &= ~(PTMAP-1); kbreak < maxkvaddr;
518 	     kbreak += PTMAP) {
519 		seg = STIDX(kbreak);
520 
521 		if (pte_find(pm, kbreak))
522 			continue;
523 
524 		if (uvm.page_init_done) {
525 			pg = (paddr_t)VM_PAGE_TO_PHYS(vm_page_alloc1());
526 		} else {
527 			if (!uvm_page_physget(&pg))
528 				panic("pmap_growkernel: no memory");
529 		}
530 		if (!pg) panic("pmap_growkernel: no pages");
531 		pmap_zero_page((paddr_t)pg);
532 
533 		/* XXX This is based on all phymem being addressable */
534 		pm->pm_ptbl[seg] = (u_int *)pg;
535 	}
536 	splx(s);
537 	return (kbreak);
538 }
539 
540 /*
541  *	vm_page_alloc1:
542  *
543  *	Allocate and return a memory cell with no associated object.
544  */
545 struct vm_page *
546 vm_page_alloc1(void)
547 {
548 	struct vm_page *pg;
549 
550 	pg = uvm_pagealloc(NULL, 0, NULL, UVM_PGA_USERESERVE);
551 	if (pg) {
552 		pg->wire_count = 1;	/* no mappings yet */
553 		pg->flags &= ~PG_BUSY;	/* never busy */
554 	}
555 	return pg;
556 }
557 
558 /*
559  *	vm_page_free1:
560  *
561  *	Returns the given page to the free list,
562  *	disassociating it with any VM object.
563  *
564  *	Object and page must be locked prior to entry.
565  */
566 void
567 vm_page_free1(struct vm_page *mem)
568 {
569 #ifdef DIAGNOSTIC
570 	if (mem->flags != (PG_CLEAN|PG_FAKE)) {
571 		printf("Freeing invalid page %p\n", mem);
572 		printf("pa = %llx\n", (unsigned long long)VM_PAGE_TO_PHYS(mem));
573 #ifdef DDB
574 		Debugger();
575 #endif
576 		return;
577 	}
578 #endif
579 	mem->flags |= PG_BUSY;
580 	mem->wire_count = 0;
581 	uvm_pagefree(mem);
582 }
583 #endif
584 
585 /*
586  * Create and return a physical map.
587  */
588 struct pmap *
589 pmap_create(void)
590 {
591 	struct pmap *pm;
592 
593 	pm = malloc(sizeof *pm, M_VMPMAP, M_WAITOK);
594 	memset(pm, 0, sizeof *pm);
595 	pm->pm_refs = 1;
596 	return pm;
597 }
598 
599 /*
600  * Add a reference to the given pmap.
601  */
602 void
603 pmap_reference(struct pmap *pm)
604 {
605 
606 	pm->pm_refs++;
607 }
608 
609 /*
610  * Retire the given pmap from service.
611  * Should only be called if the map contains no valid mappings.
612  */
613 void
614 pmap_destroy(struct pmap *pm)
615 {
616 	int i;
617 
618 	if (--pm->pm_refs > 0) {
619 		return;
620 	}
621 	KASSERT(pm->pm_stats.resident_count == 0);
622 	KASSERT(pm->pm_stats.wired_count == 0);
623 	for (i = 0; i < STSZ; i++)
624 		if (pm->pm_ptbl[i]) {
625 			uvm_km_free(kernel_map, (vaddr_t)pm->pm_ptbl[i],
626 			    PAGE_SIZE);
627 			pm->pm_ptbl[i] = NULL;
628 		}
629 	if (pm->pm_ctx)
630 		ctx_free(pm);
631 	free(pm, M_VMPMAP);
632 }
633 
634 /*
635  * Copy the range specified by src_addr/len
636  * from the source map to the range dst_addr/len
637  * in the destination map.
638  *
639  * This routine is only advisory and need not do anything.
640  */
641 void
642 pmap_copy(struct pmap *dst_pmap, struct pmap *src_pmap, vaddr_t dst_addr,
643 	  vsize_t len, vaddr_t src_addr)
644 {
645 }
646 
647 /*
648  * Require that all active physical maps contain no
649  * incorrect entries NOW.
650  */
651 void
652 pmap_update(struct pmap *pmap)
653 {
654 }
655 
656 /*
657  * Garbage collects the physical map system for
658  * pages which are no longer used.
659  * Success need not be guaranteed -- that is, there
660  * may well be pages which are not referenced, but
661  * others may be collected.
662  * Called by the pageout daemon when pages are scarce.
663  */
664 void
665 pmap_collect(struct pmap *pm)
666 {
667 }
668 
669 /*
670  * Fill the given physical page with zeroes.
671  */
672 void
673 pmap_zero_page(paddr_t pa)
674 {
675 
676 #ifdef PPC_4XX_NOCACHE
677 	memset((caddr_t)pa, 0, PAGE_SIZE);
678 #else
679 	int i;
680 
681 	for (i = PAGE_SIZE/CACHELINESIZE; i > 0; i--) {
682 		__asm __volatile ("dcbz 0,%0" :: "r"(pa));
683 		pa += CACHELINESIZE;
684 	}
685 #endif
686 }
687 
688 /*
689  * Copy the given physical source page to its destination.
690  */
691 void
692 pmap_copy_page(paddr_t src, paddr_t dst)
693 {
694 
695 	memcpy((caddr_t)dst, (caddr_t)src, PAGE_SIZE);
696 	dcache_flush_page(dst);
697 }
698 
699 /*
700  * This returns whether this is the first mapping of a page.
701  */
702 static inline int
703 pmap_enter_pv(struct pmap *pm, vaddr_t va, paddr_t pa, boolean_t wired)
704 {
705 	struct pv_entry *pv, *npv = NULL;
706 	int s;
707 
708 	if (!pmap_initialized)
709 		return 0;
710 
711 	s = splvm();
712 	pv = pa_to_pv(pa);
713 	if (!pv->pv_pm) {
714 		/*
715 		 * No entries yet, use header as the first entry.
716 		 */
717 		pv->pv_va = va;
718 		pv->pv_pm = pm;
719 		pv->pv_next = NULL;
720 	} else {
721 		/*
722 		 * There is at least one other VA mapping this page.
723 		 * Place this entry after the header.
724 		 */
725 		npv = pool_get(&pv_pool, PR_WAITOK);
726 		npv->pv_va = va;
727 		npv->pv_pm = pm;
728 		npv->pv_next = pv->pv_next;
729 		pv->pv_next = npv;
730 	}
731 	if (wired) {
732 		PV_WIRE(pv);
733 	}
734 	splx(s);
735 	return (1);
736 }
737 
738 static void
739 pmap_remove_pv(struct pmap *pm, vaddr_t va, paddr_t pa)
740 {
741 	struct pv_entry *pv, *npv;
742 
743 	/*
744 	 * Remove from the PV table.
745 	 */
746 	pv = pa_to_pv(pa);
747 	if (!pv)
748 		return;
749 
750 	/*
751 	 * If it is the first entry on the list, it is actually
752 	 * in the header and we must copy the following entry up
753 	 * to the header.  Otherwise we must search the list for
754 	 * the entry.  In either case we free the now unused entry.
755 	 */
756 	if (pm == pv->pv_pm && PV_CMPVA(va, pv)) {
757 		if (PV_ISWIRED(pv)) {
758 			pm->pm_stats.wired_count--;
759 		}
760 		if ((npv = pv->pv_next)) {
761 			*pv = *npv;
762 			pool_put(&pv_pool, npv);
763 		} else
764 			pv->pv_pm = NULL;
765 	} else {
766 		for (; (npv = pv->pv_next) != NULL; pv = npv)
767 			if (pm == npv->pv_pm && PV_CMPVA(va, npv))
768 				break;
769 		if (npv) {
770 			pv->pv_next = npv->pv_next;
771 			if (PV_ISWIRED(npv)) {
772 				pm->pm_stats.wired_count--;
773 			}
774 			pool_put(&pv_pool, npv);
775 		}
776 	}
777 }
778 
779 /*
780  * Insert physical page at pa into the given pmap at virtual address va.
781  */
782 int
783 pmap_enter(struct pmap *pm, vaddr_t va, paddr_t pa, vm_prot_t prot, int flags)
784 {
785 	int s;
786 	u_int tte;
787 	int managed;
788 
789 	/*
790 	 * Have to remove any existing mapping first.
791 	 */
792 	pmap_remove(pm, va, va + PAGE_SIZE);
793 
794 	if (flags & PMAP_WIRED)
795 		flags |= prot;
796 
797 	managed = 0;
798 	if (vm_physseg_find(atop(pa), NULL) != -1)
799 		managed = 1;
800 
801 	/*
802 	 * Generate TTE.
803 	 */
804 	tte = TTE_PA(pa);
805 	/* XXXX -- need to support multiple page sizes. */
806 	tte |= TTE_SZ_16K;
807 #ifdef	DIAGNOSTIC
808 	if ((flags & (PME_NOCACHE | PME_WRITETHROUG)) ==
809 		(PME_NOCACHE | PME_WRITETHROUG))
810 		panic("pmap_enter: uncached & writethrough");
811 #endif
812 	if (flags & PME_NOCACHE)
813 		/* Must be I/O mapping */
814 		tte |= TTE_I | TTE_G;
815 #ifdef PPC_4XX_NOCACHE
816 	tte |= TTE_I;
817 #else
818 	else if (flags & PME_WRITETHROUG)
819 		/* Uncached and writethrough are not compatible */
820 		tte |= TTE_W;
821 #endif
822 	if (pm == pmap_kernel())
823 		tte |= TTE_ZONE(ZONE_PRIV);
824 	else
825 		tte |= TTE_ZONE(ZONE_USER);
826 
827 	if (flags & VM_PROT_WRITE)
828 		tte |= TTE_WR;
829 
830 	if (flags & VM_PROT_EXECUTE)
831 		tte |= TTE_EX;
832 
833 	/*
834 	 * Now record mapping for later back-translation.
835 	 */
836 	if (pmap_initialized && managed) {
837 		char *attr;
838 
839 		if (!pmap_enter_pv(pm, va, pa, flags & PMAP_WIRED)) {
840 			/* Could not enter pv on a managed page */
841 			return 1;
842 		}
843 
844 		/* Now set attributes. */
845 		attr = pa_to_attr(pa);
846 #ifdef DIAGNOSTIC
847 		if (!attr)
848 			panic("managed but no attr");
849 #endif
850 		if (flags & VM_PROT_ALL)
851 			*attr |= PMAP_ATTR_REF;
852 		if (flags & VM_PROT_WRITE)
853 			*attr |= PMAP_ATTR_CHG;
854 	}
855 
856 	s = splvm();
857 
858 	/* Insert page into page table. */
859 	pte_enter(pm, va, tte);
860 
861 	/* If this is a real fault, enter it in the tlb */
862 	if (tte && ((flags & PMAP_WIRED) == 0)) {
863 		ppc4xx_tlb_enter(pm->pm_ctx, va, tte);
864 	}
865 	splx(s);
866 
867 	/* Flush the real memory from the instruction cache. */
868 	if ((prot & VM_PROT_EXECUTE) && (tte & TTE_I) == 0)
869 		__syncicache((void *)pa, PAGE_SIZE);
870 
871 	if (flags & PMAP_WIRED)
872 		pm->pm_stats.wired_count++;
873 
874 	return 0;
875 }
876 
877 void
878 pmap_unwire(struct pmap *pm, vaddr_t va)
879 {
880 	struct pv_entry *pv, *npv;
881 	paddr_t pa;
882 	int s;
883 
884 	if (!pmap_extract(pm, va, &pa)) {
885 		return;
886 	}
887 
888 	pv = pa_to_pv(pa);
889 	if (!pv)
890 		return;
891 
892 	/*
893 	 * If it is the first entry on the list, it is actually
894 	 * in the header and we must copy the following entry up
895 	 * to the header.  Otherwise we must search the list for
896 	 * the entry.  In either case we free the now unused entry.
897 	 */
898 	s = splvm();
899 	for (npv = pv; (npv = pv->pv_next) != NULL; pv = npv) {
900 		if (pm == npv->pv_pm && PV_CMPVA(va, npv)) {
901 			if (PV_ISWIRED(npv)) {
902 				PV_UNWIRE(npv);
903 				pm->pm_stats.wired_count--;
904 			}
905 			break;
906 		}
907 	}
908 	splx(s);
909 }
910 
911 void
912 pmap_kenter_pa(vaddr_t va, paddr_t pa, vm_prot_t prot)
913 {
914 	int s;
915 	u_int tte;
916 	struct pmap *pm = pmap_kernel();
917 
918 	/*
919 	 * Have to remove any existing mapping first.
920 	 */
921 
922 	/*
923 	 * Generate TTE.
924 	 *
925 	 * XXXX
926 	 *
927 	 * Since the kernel does not handle execution privileges properly,
928 	 * we will handle read and execute permissions together.
929 	 */
930 	tte = 0;
931 	if (prot & VM_PROT_ALL) {
932 
933 		tte = TTE_PA(pa) | TTE_EX | TTE_ZONE(ZONE_PRIV);
934 		/* XXXX -- need to support multiple page sizes. */
935 		tte |= TTE_SZ_16K;
936 #ifdef DIAGNOSTIC
937 		if ((prot & (PME_NOCACHE | PME_WRITETHROUG)) ==
938 			(PME_NOCACHE | PME_WRITETHROUG))
939 			panic("pmap_kenter_pa: uncached & writethrough");
940 #endif
941 		if (prot & PME_NOCACHE)
942 			/* Must be I/O mapping */
943 			tte |= TTE_I | TTE_G;
944 #ifdef PPC_4XX_NOCACHE
945 		tte |= TTE_I;
946 #else
947 		else if (prot & PME_WRITETHROUG)
948 			/* Uncached and writethrough are not compatible */
949 			tte |= TTE_W;
950 #endif
951 		if (prot & VM_PROT_WRITE)
952 			tte |= TTE_WR;
953 	}
954 
955 	s = splvm();
956 
957 	/* Insert page into page table. */
958 	pte_enter(pm, va, tte);
959 	splx(s);
960 }
961 
962 void
963 pmap_kremove(vaddr_t va, vsize_t len)
964 {
965 
966 	while (len > 0) {
967 		pte_enter(pmap_kernel(), va, 0);
968 		va += PAGE_SIZE;
969 		len -= PAGE_SIZE;
970 	}
971 }
972 
973 /*
974  * Remove the given range of mapping entries.
975  */
976 void
977 pmap_remove(struct pmap *pm, vaddr_t va, vaddr_t endva)
978 {
979 	int s;
980 	paddr_t pa;
981 	volatile u_int *ptp;
982 
983 	s = splvm();
984 	while (va < endva) {
985 
986 		if ((ptp = pte_find(pm, va)) && (pa = *ptp)) {
987 			pa = TTE_PA(pa);
988 			pmap_remove_pv(pm, va, pa);
989 			*ptp = 0;
990 			ppc4xx_tlb_flush(va, pm->pm_ctx);
991 			pm->pm_stats.resident_count--;
992 		}
993 		va += PAGE_SIZE;
994 	}
995 
996 	splx(s);
997 }
998 
999 /*
1000  * Get the physical page address for the given pmap/virtual address.
1001  */
1002 boolean_t
1003 pmap_extract(struct pmap *pm, vaddr_t va, paddr_t *pap)
1004 {
1005 	int seg = STIDX(va);
1006 	int ptn = PTIDX(va);
1007 	u_int pa = 0;
1008 	int s;
1009 
1010 	s = splvm();
1011 	if (pm->pm_ptbl[seg] && (pa = pm->pm_ptbl[seg][ptn])) {
1012 		*pap = TTE_PA(pa) | (va & PGOFSET);
1013 	}
1014 	splx(s);
1015 	return (pa != 0);
1016 }
1017 
1018 /*
1019  * Lower the protection on the specified range of this pmap.
1020  *
1021  * There are only two cases: either the protection is going to 0,
1022  * or it is going to read-only.
1023  */
1024 void
1025 pmap_protect(struct pmap *pm, vaddr_t sva, vaddr_t eva, vm_prot_t prot)
1026 {
1027 	volatile u_int *ptp;
1028 	int s, bic;
1029 
1030 	if ((prot & VM_PROT_READ) == 0) {
1031 		pmap_remove(pm, sva, eva);
1032 		return;
1033 	}
1034 	bic = 0;
1035 	if ((prot & VM_PROT_WRITE) == 0) {
1036 		bic |= TTE_WR;
1037 	}
1038 	if ((prot & VM_PROT_EXECUTE) == 0) {
1039 		bic |= TTE_EX;
1040 	}
1041 	if (bic == 0) {
1042 		return;
1043 	}
1044 	s = splvm();
1045 	while (sva < eva) {
1046 		if ((ptp = pte_find(pm, sva)) != NULL) {
1047 			*ptp &= ~bic;
1048 			ppc4xx_tlb_flush(sva, pm->pm_ctx);
1049 		}
1050 		sva += PAGE_SIZE;
1051 	}
1052 	splx(s);
1053 }
1054 
1055 boolean_t
1056 pmap_check_attr(struct vm_page *pg, u_int mask, int clear)
1057 {
1058 	paddr_t pa;
1059 	char *attr;
1060 	int s, rv;
1061 
1062 	/*
1063 	 * First modify bits in cache.
1064 	 */
1065 	pa = VM_PAGE_TO_PHYS(pg);
1066 	attr = pa_to_attr(pa);
1067 	if (attr == NULL)
1068 		return FALSE;
1069 
1070 	s = splvm();
1071 	rv = ((*attr & mask) != 0);
1072 	if (clear) {
1073 		*attr &= ~mask;
1074 		pmap_page_protect(pg, mask == PMAP_ATTR_CHG ? VM_PROT_READ : 0);
1075 	}
1076 	splx(s);
1077 	return rv;
1078 }
1079 
1080 
1081 /*
1082  * Lower the protection on the specified physical page.
1083  *
1084  * There are only two cases: either the protection is going to 0,
1085  * or it is going to read-only.
1086  */
1087 void
1088 pmap_page_protect(struct vm_page *pg, vm_prot_t prot)
1089 {
1090 	paddr_t pa = VM_PAGE_TO_PHYS(pg);
1091 	vaddr_t va;
1092 	struct pv_entry *pvh, *pv, *npv;
1093 	struct pmap *pm;
1094 
1095 	pvh = pa_to_pv(pa);
1096 	if (pvh == NULL)
1097 		return;
1098 
1099 	/* Handle extra pvs which may be deleted in the operation */
1100 	for (pv = pvh->pv_next; pv; pv = npv) {
1101 		npv = pv->pv_next;
1102 
1103 		pm = pv->pv_pm;
1104 		va = pv->pv_va;
1105 		pmap_protect(pm, va, va + PAGE_SIZE, prot);
1106 	}
1107 	/* Now check the head pv */
1108 	if (pvh->pv_pm) {
1109 		pv = pvh;
1110 		pm = pv->pv_pm;
1111 		va = pv->pv_va;
1112 		pmap_protect(pm, va, va + PAGE_SIZE, prot);
1113 	}
1114 }
1115 
1116 /*
1117  * Activate the address space for the specified process.  If the process
1118  * is the current process, load the new MMU context.
1119  */
1120 void
1121 pmap_activate(struct lwp *l)
1122 {
1123 #if 0
1124 	struct pcb *pcb = &l->l_proc->p_addr->u_pcb;
1125 	pmap_t pmap = l->l_proc->p_vmspace->vm_map.pmap;
1126 
1127 	/*
1128 	 * XXX Normally performed in cpu_fork().
1129 	 */
1130 	printf("pmap_activate(%p), pmap=%p\n",l,pmap);
1131 	pcb->pcb_pm = pmap;
1132 #endif
1133 }
1134 
1135 /*
1136  * Deactivate the specified process's address space.
1137  */
1138 void
1139 pmap_deactivate(struct lwp *l)
1140 {
1141 }
1142 
1143 /*
1144  * Synchronize caches corresponding to [addr, addr+len) in p.
1145  */
1146 void
1147 pmap_procwr(struct proc *p, vaddr_t va, size_t len)
1148 {
1149 	struct pmap *pm = p->p_vmspace->vm_map.pmap;
1150 	int msr, ctx, opid, step;
1151 
1152 	step = CACHELINESIZE;
1153 
1154 	/*
1155 	 * Need to turn off IMMU and switch to user context.
1156 	 * (icbi uses DMMU).
1157 	 */
1158 	if (!(ctx = pm->pm_ctx)) {
1159 		/* No context -- assign it one */
1160 		ctx_alloc(pm);
1161 		ctx = pm->pm_ctx;
1162 	}
1163 	__asm __volatile("mfmsr %0;"
1164 		"li %1, %7;"
1165 		"andc %1,%0,%1;"
1166 		"mtmsr %1;"
1167 		"sync;isync;"
1168 		"mfpid %1;"
1169 		"mtpid %2;"
1170 		"sync; isync;"
1171 		"1:"
1172 		"dcbf 0,%3;"
1173 		"icbi 0,%3;"
1174 		"add %3,%3,%5;"
1175 		"addc. %4,%4,%6;"
1176 		"bge 1b;"
1177 		"mtpid %1;"
1178 		"mtmsr %0;"
1179 		"sync; isync"
1180 		: "=&r" (msr), "=&r" (opid)
1181 		: "r" (ctx), "r" (va), "r" (len), "r" (step), "r" (-step),
1182 		  "K" (PSL_IR | PSL_DR));
1183 }
1184 
1185 
1186 /* This has to be done in real mode !!! */
1187 void
1188 ppc4xx_tlb_flush(vaddr_t va, int pid)
1189 {
1190 	u_long i, found;
1191 	u_long msr;
1192 
1193 	/* If there's no context then it can't be mapped. */
1194 	if (!pid)
1195 		return;
1196 
1197 	asm("mfpid %1;"			/* Save PID */
1198 		"mfmsr %2;"		/* Save MSR */
1199 		"li %0,0;"		/* Now clear MSR */
1200 		"mtmsr %0;"
1201 		"mtpid %4;"		/* Set PID */
1202 		"sync;"
1203 		"tlbsx. %0,0,%3;"	/* Search TLB */
1204 		"sync;"
1205 		"mtpid %1;"		/* Restore PID */
1206 		"mtmsr %2;"		/* Restore MSR */
1207 		"sync;isync;"
1208 		"li %1,1;"
1209 		"beq 1f;"
1210 		"li %1,0;"
1211 		"1:"
1212 		: "=&r" (i), "=&r" (found), "=&r" (msr)
1213 		: "r" (va), "r" (pid));
1214 	if (found && !TLB_LOCKED(i)) {
1215 
1216 		/* Now flush translation */
1217 		asm volatile(
1218 			"tlbwe %0,%1,0;"
1219 			"sync;isync;"
1220 			: : "r" (0), "r" (i));
1221 
1222 		tlb_info[i].ti_ctx = 0;
1223 		tlb_info[i].ti_flags = 0;
1224 		tlbnext = i;
1225 		/* Successful flushes */
1226 		tlbflush_ev.ev_count++;
1227 	}
1228 }
1229 
1230 void
1231 ppc4xx_tlb_flush_all(void)
1232 {
1233 	u_long i;
1234 
1235 	for (i = 0; i < NTLB; i++)
1236 		if (!TLB_LOCKED(i)) {
1237 			asm volatile(
1238 				"tlbwe %0,%1,0;"
1239 				"sync;isync;"
1240 				: : "r" (0), "r" (i));
1241 			tlb_info[i].ti_ctx = 0;
1242 			tlb_info[i].ti_flags = 0;
1243 		}
1244 
1245 	asm volatile("sync;isync");
1246 }
1247 
1248 /* Find a TLB entry to evict. */
1249 static int
1250 ppc4xx_tlb_find_victim(void)
1251 {
1252 	int flags;
1253 
1254 	for (;;) {
1255 		if (++tlbnext >= NTLB)
1256 			tlbnext = TLB_NRESERVED;
1257 		flags = tlb_info[tlbnext].ti_flags;
1258 		if (!(flags & TLBF_USED) ||
1259 			(flags & (TLBF_LOCKED | TLBF_REF)) == 0) {
1260 			u_long va, stack = (u_long)&va;
1261 
1262 			if (!((tlb_info[tlbnext].ti_va ^ stack) & (~PGOFSET)) &&
1263 			    (tlb_info[tlbnext].ti_ctx == KERNEL_PID) &&
1264 			     (flags & TLBF_USED)) {
1265 				/* Kernel stack page */
1266 				flags |= TLBF_USED;
1267 				tlb_info[tlbnext].ti_flags = flags;
1268 			} else {
1269 				/* Found it! */
1270 				return (tlbnext);
1271 			}
1272 		} else {
1273 			tlb_info[tlbnext].ti_flags = (flags & ~TLBF_REF);
1274 		}
1275 	}
1276 }
1277 
1278 void
1279 ppc4xx_tlb_enter(int ctx, vaddr_t va, u_int pte)
1280 {
1281 	u_long th, tl, idx;
1282 	tlbpid_t pid;
1283 	u_short msr;
1284 	paddr_t pa;
1285 	int s, sz;
1286 
1287 	tlbenter_ev.ev_count++;
1288 
1289 	sz = (pte & TTE_SZ_MASK) >> TTE_SZ_SHIFT;
1290 	pa = (pte & TTE_RPN_MASK(sz));
1291 	th = (va & TLB_EPN_MASK) | (sz << TLB_SIZE_SHFT) | TLB_VALID;
1292 	tl = (pte & ~TLB_RPN_MASK) | pa;
1293 	tl |= ppc4xx_tlbflags(va, pa);
1294 
1295 	s = splhigh();
1296 	idx = ppc4xx_tlb_find_victim();
1297 
1298 #ifdef DIAGNOSTIC
1299 	if ((idx < TLB_NRESERVED) || (idx >= NTLB)) {
1300 		panic("ppc4xx_tlb_enter: replacing entry %ld", idx);
1301 	}
1302 #endif
1303 
1304 	tlb_info[idx].ti_va = (va & TLB_EPN_MASK);
1305 	tlb_info[idx].ti_ctx = ctx;
1306 	tlb_info[idx].ti_flags = TLBF_USED | TLBF_REF;
1307 
1308 	asm volatile(
1309 		"mfmsr %0;"			/* Save MSR */
1310 		"li %1,0;"
1311 		"tlbwe %1,%3,0;"		/* Invalidate old entry. */
1312 		"mtmsr %1;"			/* Clear MSR */
1313 		"mfpid %1;"			/* Save old PID */
1314 		"mtpid %2;"			/* Load translation ctx */
1315 		"sync; isync;"
1316 #ifdef DEBUG
1317 		"andi. %3,%3,63;"
1318 		"tweqi %3,0;" 			/* XXXXX DEBUG trap on index 0 */
1319 #endif
1320 		"tlbwe %4,%3,1; tlbwe %5,%3,0;"	/* Set TLB */
1321 		"sync; isync;"
1322 		"mtpid %1; mtmsr %0;"		/* Restore PID and MSR */
1323 		"sync; isync;"
1324 	: "=&r" (msr), "=&r" (pid)
1325 	: "r" (ctx), "r" (idx), "r" (tl), "r" (th));
1326 	splx(s);
1327 }
1328 
1329 void
1330 ppc4xx_tlb_unpin(int i)
1331 {
1332 
1333 	if (i == -1)
1334 		for (i = 0; i < TLB_NRESERVED; i++)
1335 			tlb_info[i].ti_flags &= ~TLBF_LOCKED;
1336 	else
1337 		tlb_info[i].ti_flags &= ~TLBF_LOCKED;
1338 }
1339 
1340 void
1341 ppc4xx_tlb_init(void)
1342 {
1343 	int i;
1344 
1345 	/* Mark reserved TLB entries */
1346 	for (i = 0; i < TLB_NRESERVED; i++) {
1347 		tlb_info[i].ti_flags = TLBF_LOCKED | TLBF_USED;
1348 		tlb_info[i].ti_ctx = KERNEL_PID;
1349 	}
1350 
1351 	/* Setup security zones */
1352 	/* Z0 - accessible by kernel only if TLB entry permissions allow
1353 	 * Z1,Z2 - access is controlled by TLB entry permissions
1354 	 * Z3 - full access regardless of TLB entry permissions
1355 	 */
1356 
1357 	asm volatile(
1358 		"mtspr %0,%1;"
1359 		"sync;"
1360 		::  "K"(SPR_ZPR), "r" (0x1b000000));
1361 }
1362 
1363 
1364 /*
1365  * We should pass the ctx in from trap code.
1366  */
1367 int
1368 pmap_tlbmiss(vaddr_t va, int ctx)
1369 {
1370 	volatile u_int *pte;
1371 	u_long tte;
1372 
1373 	tlbmiss_ev.ev_count++;
1374 
1375 	/*
1376 	 * XXXX We will reserve 0-0x80000000 for va==pa mappings.
1377 	 */
1378 	if (ctx != KERNEL_PID || (va & 0x80000000)) {
1379 		pte = pte_find((struct pmap *)ctxbusy[ctx], va);
1380 		if (pte == NULL) {
1381 			/* Map unmanaged addresses directly for kernel access */
1382 			return 1;
1383 		}
1384 		tte = *pte;
1385 		if (tte == 0) {
1386 			return 1;
1387 		}
1388 	} else {
1389 		/* Create a 16MB writable mapping. */
1390 #ifdef PPC_4XX_NOCACHE
1391 		tte = TTE_PA(va) | TTE_ZONE(ZONE_PRIV) | TTE_SZ_16M | TTE_I | TTE_WR;
1392 #else
1393 		tte = TTE_PA(va) | TTE_ZONE(ZONE_PRIV) | TTE_SZ_16M | TTE_WR;
1394 #endif
1395 	}
1396 	tlbhit_ev.ev_count++;
1397 	ppc4xx_tlb_enter(ctx, va, tte);
1398 
1399 	return 0;
1400 }
1401 
1402 /*
1403  * Flush all the entries matching a context from the TLB.
1404  */
1405 static int
1406 ctx_flush(int cnum)
1407 {
1408 	int i;
1409 
1410 	/* We gotta steal this context */
1411 	for (i = TLB_NRESERVED; i < NTLB; i++) {
1412 		if (tlb_info[i].ti_ctx == cnum) {
1413 			/* Can't steal ctx if it has a locked entry. */
1414 			if (TLB_LOCKED(i)) {
1415 #ifdef DIAGNOSTIC
1416 				printf("ctx_flush: can't invalidate "
1417 					"locked mapping %d "
1418 					"for context %d\n", i, cnum);
1419 #ifdef DDB
1420 				Debugger();
1421 #endif
1422 #endif
1423 				return (1);
1424 			}
1425 #ifdef DIAGNOSTIC
1426 			if (i < TLB_NRESERVED)
1427 				panic("TLB entry %d not locked", i);
1428 #endif
1429 			/* Invalidate particular TLB entry regardless of locked status */
1430 			asm volatile("tlbwe %0,%1,0" : :"r"(0),"r"(i));
1431 			tlb_info[i].ti_flags = 0;
1432 		}
1433 	}
1434 	return (0);
1435 }
1436 
1437 /*
1438  * Allocate a context.  If necessary, steal one from someone else.
1439  *
1440  * The new context is flushed from the TLB before returning.
1441  */
1442 int
1443 ctx_alloc(struct pmap *pm)
1444 {
1445 	int s, cnum;
1446 	static int next = MINCTX;
1447 
1448 	if (pm == pmap_kernel()) {
1449 #ifdef DIAGNOSTIC
1450 		printf("ctx_alloc: kernel pmap!\n");
1451 #endif
1452 		return (0);
1453 	}
1454 	s = splvm();
1455 
1456 	/* Find a likely context. */
1457 	cnum = next;
1458 	do {
1459 		if ((++cnum) > NUMCTX)
1460 			cnum = MINCTX;
1461 	} while (ctxbusy[cnum] != NULL && cnum != next);
1462 
1463 	/* Now clean it out */
1464 oops:
1465 	if (cnum < MINCTX)
1466 		cnum = MINCTX; /* Never steal ctx 0 or 1 */
1467 	if (ctx_flush(cnum)) {
1468 		/* oops -- something's wired. */
1469 		if ((++cnum) > NUMCTX)
1470 			cnum = MINCTX;
1471 		goto oops;
1472 	}
1473 
1474 	if (ctxbusy[cnum]) {
1475 #ifdef DEBUG
1476 		/* We should identify this pmap and clear it */
1477 		printf("Warning: stealing context %d\n", cnum);
1478 #endif
1479 		ctxbusy[cnum]->pm_ctx = 0;
1480 	}
1481 	ctxbusy[cnum] = pm;
1482 	next = cnum;
1483 	splx(s);
1484 	pm->pm_ctx = cnum;
1485 
1486 	return cnum;
1487 }
1488 
1489 /*
1490  * Give away a context.
1491  */
1492 void
1493 ctx_free(struct pmap *pm)
1494 {
1495 	int oldctx;
1496 
1497 	oldctx = pm->pm_ctx;
1498 
1499 	if (oldctx == 0)
1500 		panic("ctx_free: freeing kernel context");
1501 #ifdef DIAGNOSTIC
1502 	if (ctxbusy[oldctx] == 0)
1503 		printf("ctx_free: freeing free context %d\n", oldctx);
1504 	if (ctxbusy[oldctx] != pm) {
1505 		printf("ctx_free: freeing someone esle's context\n "
1506 		       "ctxbusy[%d] = %p, pm->pm_ctx = %p\n",
1507 		       oldctx, (void *)(u_long)ctxbusy[oldctx], pm);
1508 #ifdef DDB
1509 		Debugger();
1510 #endif
1511 	}
1512 #endif
1513 	/* We should verify it has not been stolen and reallocated... */
1514 	ctxbusy[oldctx] = NULL;
1515 	ctx_flush(oldctx);
1516 }
1517 
1518 
1519 #ifdef DEBUG
1520 /*
1521  * Test ref/modify handling.
1522  */
1523 void pmap_testout __P((void));
1524 void
1525 pmap_testout()
1526 {
1527 	vaddr_t va;
1528 	volatile int *loc;
1529 	int val = 0;
1530 	paddr_t pa;
1531 	struct vm_page *pg;
1532 	int ref, mod;
1533 
1534 	/* Allocate a page */
1535 	va = (vaddr_t)uvm_km_zalloc(kernel_map, PAGE_SIZE);
1536 	loc = (int*)va;
1537 
1538 	pmap_extract(pmap_kernel(), va, &pa);
1539 	pg = PHYS_TO_VM_PAGE(pa);
1540 	pmap_unwire(pmap_kernel(), va);
1541 
1542 	pmap_remove(pmap_kernel(), va, va+1);
1543 	pmap_enter(pmap_kernel(), va, pa, VM_PROT_ALL, 0);
1544 	pmap_update(pmap_kernel());
1545 
1546 	/* Now clear reference and modify */
1547 	ref = pmap_clear_reference(pg);
1548 	mod = pmap_clear_modify(pg);
1549 	printf("Clearing page va %p pa %lx: ref %d, mod %d\n",
1550 	       (void *)(u_long)va, (long)pa,
1551 	       ref, mod);
1552 
1553 	/* Check it's properly cleared */
1554 	ref = pmap_is_referenced(pg);
1555 	mod = pmap_is_modified(pg);
1556 	printf("Checking cleared page: ref %d, mod %d\n",
1557 	       ref, mod);
1558 
1559 	/* Reference page */
1560 	val = *loc;
1561 
1562 	ref = pmap_is_referenced(pg);
1563 	mod = pmap_is_modified(pg);
1564 	printf("Referenced page: ref %d, mod %d val %x\n",
1565 	       ref, mod, val);
1566 
1567 	/* Now clear reference and modify */
1568 	ref = pmap_clear_reference(pg);
1569 	mod = pmap_clear_modify(pg);
1570 	printf("Clearing page va %p pa %lx: ref %d, mod %d\n",
1571 	       (void *)(u_long)va, (long)pa,
1572 	       ref, mod);
1573 
1574 	/* Modify page */
1575 	*loc = 1;
1576 
1577 	ref = pmap_is_referenced(pg);
1578 	mod = pmap_is_modified(pg);
1579 	printf("Modified page: ref %d, mod %d\n",
1580 	       ref, mod);
1581 
1582 	/* Now clear reference and modify */
1583 	ref = pmap_clear_reference(pg);
1584 	mod = pmap_clear_modify(pg);
1585 	printf("Clearing page va %p pa %lx: ref %d, mod %d\n",
1586 	       (void *)(u_long)va, (long)pa,
1587 	       ref, mod);
1588 
1589 	/* Check it's properly cleared */
1590 	ref = pmap_is_referenced(pg);
1591 	mod = pmap_is_modified(pg);
1592 	printf("Checking cleared page: ref %d, mod %d\n",
1593 	       ref, mod);
1594 
1595 	/* Modify page */
1596 	*loc = 1;
1597 
1598 	ref = pmap_is_referenced(pg);
1599 	mod = pmap_is_modified(pg);
1600 	printf("Modified page: ref %d, mod %d\n",
1601 	       ref, mod);
1602 
1603 	/* Check pmap_protect() */
1604 	pmap_protect(pmap_kernel(), va, va+1, VM_PROT_READ);
1605 	pmap_update(pmap_kernel());
1606 	ref = pmap_is_referenced(pg);
1607 	mod = pmap_is_modified(pg);
1608 	printf("pmap_protect(VM_PROT_READ): ref %d, mod %d\n",
1609 	       ref, mod);
1610 
1611 	/* Now clear reference and modify */
1612 	ref = pmap_clear_reference(pg);
1613 	mod = pmap_clear_modify(pg);
1614 	printf("Clearing page va %p pa %lx: ref %d, mod %d\n",
1615 	       (void *)(u_long)va, (long)pa,
1616 	       ref, mod);
1617 
1618 	/* Reference page */
1619 	val = *loc;
1620 
1621 	ref = pmap_is_referenced(pg);
1622 	mod = pmap_is_modified(pg);
1623 	printf("Referenced page: ref %d, mod %d val %x\n",
1624 	       ref, mod, val);
1625 
1626 	/* Now clear reference and modify */
1627 	ref = pmap_clear_reference(pg);
1628 	mod = pmap_clear_modify(pg);
1629 	printf("Clearing page va %p pa %lx: ref %d, mod %d\n",
1630 	       (void *)(u_long)va, (long)pa,
1631 	       ref, mod);
1632 
1633 	/* Modify page */
1634 #if 0
1635 	pmap_enter(pmap_kernel(), va, pa, VM_PROT_ALL, 0);
1636 	pmap_update(pmap_kernel());
1637 #endif
1638 	*loc = 1;
1639 
1640 	ref = pmap_is_referenced(pg);
1641 	mod = pmap_is_modified(pg);
1642 	printf("Modified page: ref %d, mod %d\n",
1643 	       ref, mod);
1644 
1645 	/* Check pmap_protect() */
1646 	pmap_protect(pmap_kernel(), va, va+1, VM_PROT_NONE);
1647 	pmap_update(pmap_kernel());
1648 	ref = pmap_is_referenced(pg);
1649 	mod = pmap_is_modified(pg);
1650 	printf("pmap_protect(): ref %d, mod %d\n",
1651 	       ref, mod);
1652 
1653 	/* Now clear reference and modify */
1654 	ref = pmap_clear_reference(pg);
1655 	mod = pmap_clear_modify(pg);
1656 	printf("Clearing page va %p pa %lx: ref %d, mod %d\n",
1657 	       (void *)(u_long)va, (long)pa,
1658 	       ref, mod);
1659 
1660 	/* Reference page */
1661 	val = *loc;
1662 
1663 	ref = pmap_is_referenced(pg);
1664 	mod = pmap_is_modified(pg);
1665 	printf("Referenced page: ref %d, mod %d val %x\n",
1666 	       ref, mod, val);
1667 
1668 	/* Now clear reference and modify */
1669 	ref = pmap_clear_reference(pg);
1670 	mod = pmap_clear_modify(pg);
1671 	printf("Clearing page va %p pa %lx: ref %d, mod %d\n",
1672 	       (void *)(u_long)va, (long)pa,
1673 	       ref, mod);
1674 
1675 	/* Modify page */
1676 #if 0
1677 	pmap_enter(pmap_kernel(), va, pa, VM_PROT_ALL, 0);
1678 	pmap_update(pmap_kernel());
1679 #endif
1680 	*loc = 1;
1681 
1682 	ref = pmap_is_referenced(pg);
1683 	mod = pmap_is_modified(pg);
1684 	printf("Modified page: ref %d, mod %d\n",
1685 	       ref, mod);
1686 
1687 	/* Check pmap_pag_protect() */
1688 	pmap_page_protect(pg, VM_PROT_READ);
1689 	ref = pmap_is_referenced(pg);
1690 	mod = pmap_is_modified(pg);
1691 	printf("pmap_page_protect(VM_PROT_READ): ref %d, mod %d\n",
1692 	       ref, mod);
1693 
1694 	/* Now clear reference and modify */
1695 	ref = pmap_clear_reference(pg);
1696 	mod = pmap_clear_modify(pg);
1697 	printf("Clearing page va %p pa %lx: ref %d, mod %d\n",
1698 	       (void *)(u_long)va, (long)pa,
1699 	       ref, mod);
1700 
1701 	/* Reference page */
1702 	val = *loc;
1703 
1704 	ref = pmap_is_referenced(pg);
1705 	mod = pmap_is_modified(pg);
1706 	printf("Referenced page: ref %d, mod %d val %x\n",
1707 	       ref, mod, val);
1708 
1709 	/* Now clear reference and modify */
1710 	ref = pmap_clear_reference(pg);
1711 	mod = pmap_clear_modify(pg);
1712 	printf("Clearing page va %p pa %lx: ref %d, mod %d\n",
1713 	       (void *)(u_long)va, (long)pa,
1714 	       ref, mod);
1715 
1716 	/* Modify page */
1717 #if 0
1718 	pmap_enter(pmap_kernel(), va, pa, VM_PROT_ALL, 0);
1719 	pmap_update(pmap_kernel());
1720 #endif
1721 	*loc = 1;
1722 
1723 	ref = pmap_is_referenced(pg);
1724 	mod = pmap_is_modified(pg);
1725 	printf("Modified page: ref %d, mod %d\n",
1726 	       ref, mod);
1727 
1728 	/* Check pmap_pag_protect() */
1729 	pmap_page_protect(pg, VM_PROT_NONE);
1730 	ref = pmap_is_referenced(pg);
1731 	mod = pmap_is_modified(pg);
1732 	printf("pmap_page_protect(): ref %d, mod %d\n",
1733 	       ref, mod);
1734 
1735 	/* Now clear reference and modify */
1736 	ref = pmap_clear_reference(pg);
1737 	mod = pmap_clear_modify(pg);
1738 	printf("Clearing page va %p pa %lx: ref %d, mod %d\n",
1739 	       (void *)(u_long)va, (long)pa,
1740 	       ref, mod);
1741 
1742 
1743 	/* Reference page */
1744 	val = *loc;
1745 
1746 	ref = pmap_is_referenced(pg);
1747 	mod = pmap_is_modified(pg);
1748 	printf("Referenced page: ref %d, mod %d val %x\n",
1749 	       ref, mod, val);
1750 
1751 	/* Now clear reference and modify */
1752 	ref = pmap_clear_reference(pg);
1753 	mod = pmap_clear_modify(pg);
1754 	printf("Clearing page va %p pa %lx: ref %d, mod %d\n",
1755 	       (void *)(u_long)va, (long)pa,
1756 	       ref, mod);
1757 
1758 	/* Modify page */
1759 #if 0
1760 	pmap_enter(pmap_kernel(), va, pa, VM_PROT_ALL, 0);
1761 	pmap_update(pmap_kernel());
1762 #endif
1763 	*loc = 1;
1764 
1765 	ref = pmap_is_referenced(pg);
1766 	mod = pmap_is_modified(pg);
1767 	printf("Modified page: ref %d, mod %d\n",
1768 	       ref, mod);
1769 
1770 	/* Unmap page */
1771 	pmap_remove(pmap_kernel(), va, va+1);
1772 	pmap_update(pmap_kernel());
1773 	ref = pmap_is_referenced(pg);
1774 	mod = pmap_is_modified(pg);
1775 	printf("Unmapped page: ref %d, mod %d\n", ref, mod);
1776 
1777 	/* Now clear reference and modify */
1778 	ref = pmap_clear_reference(pg);
1779 	mod = pmap_clear_modify(pg);
1780 	printf("Clearing page va %p pa %lx: ref %d, mod %d\n",
1781 	       (void *)(u_long)va, (long)pa, ref, mod);
1782 
1783 	/* Check it's properly cleared */
1784 	ref = pmap_is_referenced(pg);
1785 	mod = pmap_is_modified(pg);
1786 	printf("Checking cleared page: ref %d, mod %d\n",
1787 	       ref, mod);
1788 
1789 	pmap_enter(pmap_kernel(), va, pa, VM_PROT_ALL,
1790 		VM_PROT_ALL|PMAP_WIRED);
1791 	uvm_km_free(kernel_map, (vaddr_t)va, PAGE_SIZE);
1792 }
1793 #endif
1794