xref: /netbsd-src/sys/arch/powerpc/booke/e500_tlb.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /*	$NetBSD: e500_tlb.c,v 1.13 2013/12/09 09:35:16 wiz Exp $	*/
2 /*-
3  * Copyright (c) 2010, 2011 The NetBSD Foundation, Inc.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to The NetBSD Foundation
7  * by Raytheon BBN Technologies Corp and Defense Advanced Research Projects
8  * Agency and which was developed by Matt Thomas of 3am Software Foundry.
9  *
10  * This material is based upon work supported by the Defense Advanced Research
11  * Projects Agency and Space and Naval Warfare Systems Center, Pacific, under
12  * Contract No. N66001-09-C-2073.
13  * Approved for Public Release, Distribution Unlimited
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
25  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
26  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
27  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
28  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34  * POSSIBILITY OF SUCH DAMAGE.
35  */
36 
37 #define	__PMAP_PRIVATE
38 
39 #include <sys/cdefs.h>
40 
41 __KERNEL_RCSID(0, "$NetBSD: e500_tlb.c,v 1.13 2013/12/09 09:35:16 wiz Exp $");
42 
43 #include <sys/param.h>
44 
45 #include <uvm/uvm_extern.h>
46 
47 #include <powerpc/spr.h>
48 #include <powerpc/booke/spr.h>
49 #include <powerpc/booke/cpuvar.h>
50 #include <powerpc/booke/e500reg.h>
51 #include <powerpc/booke/e500var.h>
52 #include <powerpc/booke/pmap.h>
53 
54 struct e500_tlb {
55 	vaddr_t tlb_va;
56 	uint32_t tlb_pte;
57 	uint32_t tlb_asid;
58 	vsize_t tlb_size;
59 };
60 
61 struct e500_hwtlb {
62 	uint32_t hwtlb_mas0;
63 	uint32_t hwtlb_mas1;
64 	uint32_t hwtlb_mas2;
65 	uint32_t hwtlb_mas3;
66 };
67 
68 struct e500_xtlb {
69 	struct e500_tlb e_tlb;
70 	struct e500_hwtlb e_hwtlb;
71 	u_long e_refcnt;
72 };
73 
74 static struct e500_tlb1 {
75 	uint32_t tlb1_maxsize;
76 	uint32_t tlb1_minsize;
77 	u_int tlb1_numentries;
78 	u_int tlb1_numfree;
79 	u_int tlb1_freelist[32];
80 	struct e500_xtlb tlb1_entries[32];
81 } e500_tlb1;
82 
83 static inline register_t mftlb0cfg(void) __pure;
84 static inline register_t mftlb1cfg(void) __pure;
85 
86 static inline register_t
87 mftlb0cfg(void)
88 {
89 	register_t tlb0cfg;
90 	__asm("mfspr %0, %1" : "=r"(tlb0cfg) : "n"(SPR_TLB0CFG));
91 	return tlb0cfg;
92 }
93 
94 static inline register_t
95 mftlb1cfg(void)
96 {
97 	register_t tlb1cfg;
98 	__asm("mfspr %0, %1" : "=r"(tlb1cfg) : "n"(SPR_TLB1CFG));
99 	return tlb1cfg;
100 }
101 
102 static struct e500_tlb
103 hwtlb_to_tlb(const struct e500_hwtlb hwtlb)
104 {
105 	struct e500_tlb tlb;
106 	register_t prot_mask;
107 	u_int prot_shift;
108 
109 	tlb.tlb_va = MAS2_EPN & hwtlb.hwtlb_mas2;
110 	tlb.tlb_size = 1024 << (2 * MASX_TSIZE_GET(hwtlb.hwtlb_mas1));
111 	tlb.tlb_asid = MASX_TID_GET(hwtlb.hwtlb_mas1);
112 	tlb.tlb_pte = (hwtlb.hwtlb_mas2 & MAS2_WIMGE)
113 	    | (hwtlb.hwtlb_mas3 & MAS3_RPN);
114 	if (hwtlb.hwtlb_mas1 & MAS1_TS) {
115 		prot_mask = MAS3_UX|MAS3_UW|MAS3_UR;
116 		prot_shift = PTE_RWX_SHIFT - 1;
117 	} else {
118 		prot_mask = MAS3_SX|MAS3_SW|MAS3_SR;
119 		prot_shift = PTE_RWX_SHIFT;
120 	}
121 	tlb.tlb_pte |= (prot_mask & hwtlb.hwtlb_mas3) << prot_shift;
122 	return tlb;
123 }
124 
125 static inline struct e500_hwtlb
126 hwtlb_read(uint32_t mas0, u_int slot)
127 {
128 	struct e500_hwtlb hwtlb;
129 	register_t tlbcfg;
130 
131 	if (__predict_true(mas0 == MAS0_TLBSEL_TLB0)) {
132 		tlbcfg = mftlb0cfg();
133 	} else if (mas0 == MAS0_TLBSEL_TLB1) {
134 		tlbcfg = mftlb1cfg();
135 	} else {
136 		panic("%s:%d: unexpected MAS0 %#" PRIx32,
137 		    __func__, __LINE__, mas0);
138 	}
139 
140 	/*
141 	 * ESEL is the way we want to look up.
142 	 * If tlbassoc is the same as tlbentries (like in TLB1) then the TLB is
143 	 * fully associative, the entire slot is placed into ESEL.  If tlbassoc
144 	 * is less than the number of tlb entries, the slot is split in two
145 	 * fields.  Since the TLB is M rows by N ways, the lowers bits are for
146 	 * row (MAS2[EPN]) and the upper for the way (MAS1[ESEL]).
147 	 */
148 	const u_int tlbassoc = TLBCFG_ASSOC(tlbcfg);
149 	const u_int tlbentries = TLBCFG_NENTRY(tlbcfg);
150 	const u_int esel_shift =
151 	    __builtin_clz(tlbassoc) - __builtin_clz(tlbentries);
152 
153 	/*
154 	 * Disable interrupts since we don't want anyone else mucking with
155 	 * the MMU Assist registers
156 	 */
157 	const register_t msr = wrtee(0);
158 	const register_t saved_mas0 = mfspr(SPR_MAS0);
159 	mtspr(SPR_MAS0, mas0 | MAS0_ESEL_MAKE(slot >> esel_shift));
160 
161 	if (__predict_true(tlbassoc > tlbentries))
162 		mtspr(SPR_MAS2, slot << PAGE_SHIFT);
163 
164 	/*
165 	 * Now select the entry and grab its contents.
166 	 */
167 	__asm volatile("tlbre");
168 
169 	hwtlb.hwtlb_mas0 = mfspr(SPR_MAS0);
170 	hwtlb.hwtlb_mas1 = mfspr(SPR_MAS1);
171 	hwtlb.hwtlb_mas2 = mfspr(SPR_MAS2);
172 	hwtlb.hwtlb_mas3 = mfspr(SPR_MAS3);
173 
174 	mtspr(SPR_MAS0, saved_mas0);
175 	wrtee(msr);	/* restore interrupts */
176 
177 	return hwtlb;
178 }
179 
180 static inline void
181 hwtlb_write(const struct e500_hwtlb hwtlb, bool needs_sync)
182 {
183 	const register_t msr = wrtee(0);
184 	const uint32_t saved_mas0 = mfspr(SPR_MAS0);
185 
186 	/*
187 	 * Need to always write MAS0 and MAS1
188 	 */
189 	mtspr(SPR_MAS0, hwtlb.hwtlb_mas0);
190 	mtspr(SPR_MAS1, hwtlb.hwtlb_mas1);
191 
192 	/*
193 	 * Only write the VPN/WIMGE if this is in TLB0 or if a valid mapping.
194 	 */
195 	if ((hwtlb.hwtlb_mas0 & MAS0_TLBSEL) == MAS0_TLBSEL_TLB0
196 	    || (hwtlb.hwtlb_mas1 & MAS1_V)) {
197 		mtspr(SPR_MAS2, hwtlb.hwtlb_mas2);
198 	}
199 	/*
200 	 * Only need to write the RPN/prot if we are dealing with a valid
201 	 * mapping.
202 	 */
203 	if (hwtlb.hwtlb_mas1 & MAS1_V) {
204 		mtspr(SPR_MAS3, hwtlb.hwtlb_mas3);
205 		//mtspr(SPR_MAS7, 0);
206 	}
207 
208 #if 0
209 	printf("%s->[%x,%x,%x,%x]\n",
210 	    __func__,
211 	    hwtlb.hwtlb_mas0, hwtlb.hwtlb_mas1,
212 	    hwtlb.hwtlb_mas2, hwtlb.hwtlb_mas3);
213 #endif
214 	__asm volatile("tlbwe");
215 	if (needs_sync) {
216 		__asm volatile("tlbsync\n\tisync\n\tsync");
217 	}
218 
219 	mtspr(SPR_MAS0, saved_mas0);
220 	wrtee(msr);
221 }
222 
223 static struct e500_hwtlb
224 tlb_to_hwtlb(const struct e500_tlb tlb)
225 {
226 	struct e500_hwtlb hwtlb;
227 
228 	KASSERT(trunc_page(tlb.tlb_va) == tlb.tlb_va);
229 	KASSERT(tlb.tlb_size != 0);
230 	KASSERT((tlb.tlb_size & (tlb.tlb_size - 1)) == 0);
231 	const uint32_t prot_mask = tlb.tlb_pte & PTE_RWX_MASK;
232 	if (__predict_true(tlb.tlb_size == PAGE_SIZE)) {
233 		hwtlb.hwtlb_mas0 = 0;
234 		hwtlb.hwtlb_mas1 = MAS1_V | MASX_TSIZE_MAKE(1);
235 		/*
236 		 * A non-zero ASID means this is a user page so mark it as
237 		 * being in the user's address space.
238 		 */
239 		if (tlb.tlb_asid) {
240 			hwtlb.hwtlb_mas1 |= MAS1_TS
241 			    | MASX_TID_MAKE(tlb.tlb_asid);
242 			hwtlb.hwtlb_mas3 = (prot_mask >> (PTE_RWX_SHIFT - 1))
243 			    | ((prot_mask & ~PTE_xX) >> PTE_RWX_SHIFT);
244 			KASSERT(prot_mask & PTE_xR);
245 			KASSERT(hwtlb.hwtlb_mas3 & MAS3_UR);
246 			CTASSERT(MAS3_UR == (PTE_xR >> (PTE_RWX_SHIFT - 1)));
247 			CTASSERT(MAS3_SR == (PTE_xR >> PTE_RWX_SHIFT));
248 		} else {
249 			hwtlb.hwtlb_mas3 = prot_mask >> PTE_RWX_SHIFT;
250 		}
251 		if (tlb.tlb_pte & PTE_UNMODIFIED)
252 			hwtlb.hwtlb_mas3 &= ~(MAS3_UW|MAS3_SW);
253 		if (tlb.tlb_pte & PTE_UNSYNCED)
254 			hwtlb.hwtlb_mas3 &= ~(MAS3_UX|MAS3_SX);
255 	} else {
256 		KASSERT(tlb.tlb_asid == 0);
257 		KASSERT((tlb.tlb_size & 0xaaaaa7ff) == 0);
258 		u_int cntlz = __builtin_clz(tlb.tlb_size);
259 		KASSERT(cntlz & 1);
260 		KASSERT(cntlz <= 19);
261 		hwtlb.hwtlb_mas0 = MAS0_TLBSEL_TLB1;
262 		/*
263 		 * TSIZE is defined (4^TSIZE) Kbytes except a TSIZE of 0 is not
264 		 * allowed.  So 1K would be 0x00000400 giving 21 leading zero
265 		 * bits.  Subtracting the leading number of zero bits from 21
266 		 * and dividing by 2 gives us the number that the MMU wants.
267 		 */
268 		hwtlb.hwtlb_mas1 = MASX_TSIZE_MAKE(((31 - 10) - cntlz) / 2)
269 		    | MAS1_IPROT | MAS1_V;
270 		hwtlb.hwtlb_mas3 = prot_mask >> PTE_RWX_SHIFT;
271 	}
272 	/* We are done with MAS1, on to MAS2 ... */
273 	hwtlb.hwtlb_mas2 = tlb.tlb_va | (tlb.tlb_pte & PTE_WIMGE_MASK);
274 	hwtlb.hwtlb_mas3 |= tlb.tlb_pte & PTE_RPN_MASK;
275 
276 	return hwtlb;
277 }
278 
279 void *
280 e500_tlb1_fetch(size_t slot)
281 {
282 	struct e500_tlb1 * const tlb1 = &e500_tlb1;
283 
284 	return &tlb1->tlb1_entries[slot].e_hwtlb;
285 }
286 
287 void
288 e500_tlb1_sync(void)
289 {
290 	struct e500_tlb1 * const tlb1 = &e500_tlb1;
291 	for (u_int slot = 1; slot < tlb1->tlb1_numentries; slot++) {
292 		const struct e500_hwtlb * const new_hwtlb =
293 		    &tlb1->tlb1_entries[slot].e_hwtlb;
294 		const struct e500_hwtlb old_hwtlb =
295 		    hwtlb_read(MAS0_TLBSEL_TLB1, slot);
296 #define CHANGED(n,o,f)	((n)->f != (o).f)
297 		bool mas1_changed_p = CHANGED(new_hwtlb, old_hwtlb, hwtlb_mas1);
298 		bool mas2_changed_p = CHANGED(new_hwtlb, old_hwtlb, hwtlb_mas2);
299 		bool mas3_changed_p = CHANGED(new_hwtlb, old_hwtlb, hwtlb_mas3);
300 #undef CHANGED
301 		bool new_valid_p = (new_hwtlb->hwtlb_mas1 & MAS1_V) != 0;
302 		bool old_valid_p = (old_hwtlb.hwtlb_mas1 & MAS1_V) != 0;
303 		if ((new_valid_p || old_valid_p)
304 		    && (mas1_changed_p
305 			|| (new_valid_p
306 			    && (mas2_changed_p || mas3_changed_p))))
307 			hwtlb_write(*new_hwtlb, true);
308 	}
309 }
310 
311 static int
312 e500_alloc_tlb1_entry(void)
313 {
314 	struct e500_tlb1 * const tlb1 = &e500_tlb1;
315 
316 	if (tlb1->tlb1_numfree == 0)
317 		return -1;
318 	const u_int slot = tlb1->tlb1_freelist[--tlb1->tlb1_numfree];
319 	KASSERT((tlb1->tlb1_entries[slot].e_hwtlb.hwtlb_mas1 & MAS1_V) == 0);
320 	tlb1->tlb1_entries[slot].e_hwtlb.hwtlb_mas0 =
321 	    MAS0_TLBSEL_TLB1 | __SHIFTIN(slot, MAS0_ESEL);
322 	return (int)slot;
323 }
324 
325 static void
326 e500_free_tlb1_entry(struct e500_xtlb *xtlb, u_int slot, bool needs_sync)
327 {
328 	struct e500_tlb1 * const tlb1 = &e500_tlb1;
329 	KASSERT(slot < tlb1->tlb1_numentries);
330 	KASSERT(&tlb1->tlb1_entries[slot] == xtlb);
331 
332 	KASSERT(xtlb->e_hwtlb.hwtlb_mas0 == (MAS0_TLBSEL_TLB1|__SHIFTIN(slot, MAS0_ESEL)));
333 	xtlb->e_hwtlb.hwtlb_mas1 &= ~(MAS1_V|MAS1_IPROT);
334 	hwtlb_write(xtlb->e_hwtlb, needs_sync);
335 
336 	const register_t msr = wrtee(0);
337 	tlb1->tlb1_freelist[tlb1->tlb1_numfree++] = slot;
338 	wrtee(msr);
339 }
340 
341 static tlb_asid_t
342 e500_tlb_get_asid(void)
343 {
344 	return mfspr(SPR_PID0);
345 }
346 
347 static void
348 e500_tlb_set_asid(tlb_asid_t asid)
349 {
350 	mtspr(SPR_PID0, asid);
351 }
352 
353 static void
354 e500_tlb_invalidate_all(void)
355 {
356 	/*
357 	 * This does a flash invalidate of all entries in TLB0.
358 	 * We don't touch TLB1 since we don't expect those to be volatile.
359 	 */
360 #if 1
361 	__asm volatile("tlbivax\t0, %0" :: "b"(4));	/* INV_ALL */
362 	__asm volatile("tlbsync\n\tisync\n\tsync");
363 #else
364 	mtspr(SPR_MMUCSR0, MMUCSR0_TLB0_FL);
365 	while (mfspr(SPR_MMUCSR0) != 0)
366 		;
367 #endif
368 }
369 
370 static void
371 e500_tlb_invalidate_globals(void)
372 {
373 	const size_t tlbassoc = TLBCFG_ASSOC(mftlb0cfg());
374 	const size_t tlbentries = TLBCFG_NENTRY(mftlb0cfg());
375 	const size_t max_epn = (tlbentries / tlbassoc) << PAGE_SHIFT;
376 	const vaddr_t kstack_lo = (uintptr_t)curlwp->l_addr;
377 	const vaddr_t kstack_hi = kstack_lo + USPACE - 1;
378 	const vaddr_t epn_kstack_lo = kstack_lo & (max_epn - 1);
379 	const vaddr_t epn_kstack_hi = kstack_hi & (max_epn - 1);
380 
381 	const register_t msr = wrtee(0);
382 	for (size_t assoc = 0; assoc < tlbassoc; assoc++) {
383 		mtspr(SPR_MAS0, MAS0_ESEL_MAKE(assoc) | MAS0_TLBSEL_TLB0);
384 		for (size_t epn = 0; epn < max_epn; epn += PAGE_SIZE) {
385 			mtspr(SPR_MAS2, epn);
386 			__asm volatile("tlbre");
387 			uint32_t mas1 = mfspr(SPR_MAS1);
388 
389 			/*
390 			 * Make sure this is a valid kernel entry first.
391 			 */
392 			if ((mas1 & (MAS1_V|MAS1_TID|MAS1_TS)) != MAS1_V)
393 				continue;
394 
395 			/*
396 			 * We have a valid kernel TLB entry.  But if it matches
397 			 * the stack we are currently running on, it would
398 			 * unwise to invalidate it.  First see if the epn
399 			 * overlaps the stack.  If it does then get the
400 			 * VA and see if it really is part of the stack.
401 			 */
402 			if (epn_kstack_lo < epn_kstack_hi
403 			    ? (epn_kstack_lo <= epn && epn <= epn_kstack_hi)
404 			    : (epn <= epn_kstack_hi || epn_kstack_lo <= epn)) {
405 				const uint32_t mas2_epn =
406 				    mfspr(SPR_MAS2) & MAS2_EPN;
407 				if (kstack_lo <= mas2_epn
408 				    && mas2_epn <= kstack_hi)
409 					continue;
410 			}
411 			mtspr(SPR_MAS1, mas1 ^ MAS1_V);
412 			__asm volatile("tlbwe");
413 		}
414 	}
415 	__asm volatile("isync\n\tsync");
416 	wrtee(msr);
417 }
418 
419 static void
420 e500_tlb_invalidate_asids(tlb_asid_t asid_lo, tlb_asid_t asid_hi)
421 {
422 	const size_t tlbassoc = TLBCFG_ASSOC(mftlb0cfg());
423 	const size_t tlbentries = TLBCFG_NENTRY(mftlb0cfg());
424 	const size_t max_epn = (tlbentries / tlbassoc) << PAGE_SHIFT;
425 
426 	asid_lo = __SHIFTIN(asid_lo, MAS1_TID);
427 	asid_hi = __SHIFTIN(asid_hi, MAS1_TID);
428 
429 	const register_t msr = wrtee(0);
430 	for (size_t assoc = 0; assoc < tlbassoc; assoc++) {
431 		mtspr(SPR_MAS0, MAS0_ESEL_MAKE(assoc) | MAS0_TLBSEL_TLB0);
432 		for (size_t epn = 0; epn < max_epn; epn += PAGE_SIZE) {
433 			mtspr(SPR_MAS2, epn);
434 			__asm volatile("tlbre");
435 			const uint32_t mas1 = mfspr(SPR_MAS1);
436 			/*
437 			 * If this is a valid entry for AS space 1 and
438 			 * its asid matches the constraints of the caller,
439 			 * clear its valid bit.
440 			 */
441 			if ((mas1 & (MAS1_V|MAS1_TS)) == (MAS1_V|MAS1_TS)
442 			    && asid_lo <= (mas1 & MAS1_TID)
443 			    && (mas1 & MAS1_TID) <= asid_hi) {
444 				mtspr(SPR_MAS1, mas1 ^ MAS1_V);
445 #if 0
446 				printf("%s[%zu,%zu]->[%x]\n",
447 				    __func__, assoc, epn, mas1);
448 #endif
449 				__asm volatile("tlbwe");
450 			}
451 		}
452 	}
453 	__asm volatile("isync\n\tsync");
454 	wrtee(msr);
455 }
456 
457 static u_int
458 e500_tlb_record_asids(u_long *bitmap)
459 {
460 	const size_t tlbassoc = TLBCFG_ASSOC(mftlb0cfg());
461 	const size_t tlbentries = TLBCFG_NENTRY(mftlb0cfg());
462 	const size_t max_epn = (tlbentries / tlbassoc) << PAGE_SHIFT;
463 	const size_t nbits = 8 * sizeof(bitmap[0]);
464 	u_int found = 0;
465 
466 	const register_t msr = wrtee(0);
467 	for (size_t assoc = 0; assoc < tlbassoc; assoc++) {
468 		mtspr(SPR_MAS0, MAS0_ESEL_MAKE(assoc) | MAS0_TLBSEL_TLB0);
469 		for (size_t epn = 0; epn < max_epn; epn += PAGE_SIZE) {
470 			mtspr(SPR_MAS2, epn);
471 			__asm volatile("tlbre");
472 			const uint32_t mas1 = mfspr(SPR_MAS1);
473 			/*
474 			 * If this is a valid entry for AS space 1 and
475 			 * its asid matches the constraints of the caller,
476 			 * clear its valid bit.
477 			 */
478 			if ((mas1 & (MAS1_V|MAS1_TS)) == (MAS1_V|MAS1_TS)) {
479 				const uint32_t asid = MASX_TID_GET(mas1);
480 				const u_int i = asid / nbits;
481 				const u_long mask = 1UL << (asid & (nbits - 1));
482 				if ((bitmap[i] & mask) == 0) {
483 					bitmap[i] |= mask;
484 					found++;
485 				}
486 			}
487 		}
488 	}
489 	wrtee(msr);
490 
491 	return found;
492 }
493 
494 static void
495 e500_tlb_invalidate_addr(vaddr_t va, tlb_asid_t asid)
496 {
497 	KASSERT((va & PAGE_MASK) == 0);
498 	/*
499 	 * Bits 60 & 61 have meaning
500 	 */
501 	if (asid == KERNEL_PID) {
502 		/*
503 		 * For data accesses, the context-synchronizing instruction
504 		 * before tlbwe or tlbivax ensures that all memory accesses
505 		 * due to preceding instructions have completed to a point
506 		 * at which they have reported all exceptions they will cause.
507 		 */
508 		__asm volatile("isync");
509 	}
510 	__asm volatile("tlbivax\t0, %0" :: "b"(va));
511 	__asm volatile("tlbsync");
512 	__asm volatile("tlbsync");	/* Why? */
513 	if (asid == KERNEL_PID) {
514 		/*
515 		 * The context-synchronizing instruction after tlbwe or tlbivax
516 		 * ensures that subsequent accesses (data and instruction) use
517 		 * the updated value in any TLB entries affected.
518 		 */
519 		__asm volatile("isync\n\tsync");
520 	}
521 }
522 
523 static bool
524 e500_tlb_update_addr(vaddr_t va, tlb_asid_t asid, pt_entry_t pte, bool insert)
525 {
526 	struct e500_hwtlb hwtlb = tlb_to_hwtlb(
527 	    (struct e500_tlb){ .tlb_va = va, .tlb_asid = asid,
528 		.tlb_size = PAGE_SIZE, .tlb_pte = pte,});
529 
530 	register_t msr = wrtee(0);
531 	mtspr(SPR_MAS6, asid ? __SHIFTIN(asid, MAS6_SPID0) | MAS6_SAS : 0);
532 	__asm volatile("tlbsx 0, %0" :: "b"(va));
533 	register_t mas1 = mfspr(SPR_MAS1);
534 	if ((mas1 & MAS1_V) == 0) {
535 		if (!insert) {
536 			wrtee(msr);
537 #if 0
538 			printf("%s(%#lx,%#x,%#x,%x)<no update>\n",
539 			    __func__, va, asid, pte, insert);
540 #endif
541 			return false;
542 		}
543 		mtspr(SPR_MAS1, hwtlb.hwtlb_mas1);
544 	}
545 	mtspr(SPR_MAS2, hwtlb.hwtlb_mas2);
546 	mtspr(SPR_MAS3, hwtlb.hwtlb_mas3);
547 	//mtspr(SPR_MAS7, 0);
548 	__asm volatile("tlbwe");
549 	if (asid == KERNEL_PID)
550 		__asm volatile("isync\n\tsync");
551 	wrtee(msr);
552 #if 0
553 	if (asid)
554 	printf("%s(%#lx,%#x,%#x,%x)->[%x,%x,%x]\n",
555 	    __func__, va, asid, pte, insert,
556 	    hwtlb.hwtlb_mas1, hwtlb.hwtlb_mas2, hwtlb.hwtlb_mas3);
557 #endif
558 	return (mas1 & MAS1_V) != 0;
559 }
560 
561 static void
562 e500_tlb_write_entry(size_t index, const struct tlbmask *tlb)
563 {
564 }
565 
566 static void
567 e500_tlb_read_entry(size_t index, struct tlbmask *tlb)
568 {
569 }
570 
571 static void
572 e500_tlb_dump(void (*pr)(const char *, ...))
573 {
574 	const size_t tlbassoc = TLBCFG_ASSOC(mftlb0cfg());
575 	const size_t tlbentries = TLBCFG_NENTRY(mftlb0cfg());
576 	const size_t max_epn = (tlbentries / tlbassoc) << PAGE_SHIFT;
577 	const uint32_t saved_mas0 = mfspr(SPR_MAS0);
578 	size_t valid = 0;
579 
580 	if (pr == NULL)
581 		pr = printf;
582 
583 	const register_t msr = wrtee(0);
584 	for (size_t assoc = 0; assoc < tlbassoc; assoc++) {
585 		struct e500_hwtlb hwtlb;
586 		hwtlb.hwtlb_mas0 = MAS0_ESEL_MAKE(assoc) | MAS0_TLBSEL_TLB0;
587 		mtspr(SPR_MAS0, hwtlb.hwtlb_mas0);
588 		for (size_t epn = 0; epn < max_epn; epn += PAGE_SIZE) {
589 			mtspr(SPR_MAS2, epn);
590 			__asm volatile("tlbre");
591 			hwtlb.hwtlb_mas1 = mfspr(SPR_MAS1);
592 			/*
593 			 * If this is a valid entry for AS space 1 and
594 			 * its asid matches the constraints of the caller,
595 			 * clear its valid bit.
596 			 */
597 			if (hwtlb.hwtlb_mas1 & MAS1_V) {
598 				hwtlb.hwtlb_mas2 = mfspr(SPR_MAS2);
599 				hwtlb.hwtlb_mas3 = mfspr(SPR_MAS3);
600 				struct e500_tlb tlb = hwtlb_to_tlb(hwtlb);
601 				(*pr)("[%zu,%zu]->[%x,%x,%x]",
602 				    assoc, atop(epn),
603 				    hwtlb.hwtlb_mas1,
604 				    hwtlb.hwtlb_mas2,
605 				    hwtlb.hwtlb_mas3);
606 				(*pr)(": VA=%#lx size=4KB asid=%u pte=%x",
607 				    tlb.tlb_va, tlb.tlb_asid, tlb.tlb_pte);
608 				(*pr)(" (RPN=%#x,%s%s%s%s%s,%s%s%s%s%s)\n",
609 				    tlb.tlb_pte & PTE_RPN_MASK,
610 				    tlb.tlb_pte & PTE_xR ? "R" : "",
611 				    tlb.tlb_pte & PTE_xW ? "W" : "",
612 				    tlb.tlb_pte & PTE_UNMODIFIED ? "*" : "",
613 				    tlb.tlb_pte & PTE_xX ? "X" : "",
614 				    tlb.tlb_pte & PTE_UNSYNCED ? "*" : "",
615 				    tlb.tlb_pte & PTE_W ? "W" : "",
616 				    tlb.tlb_pte & PTE_I ? "I" : "",
617 				    tlb.tlb_pte & PTE_M ? "M" : "",
618 				    tlb.tlb_pte & PTE_G ? "G" : "",
619 				    tlb.tlb_pte & PTE_E ? "E" : "");
620 				valid++;
621 			}
622 		}
623 	}
624 	mtspr(SPR_MAS0, saved_mas0);
625 	wrtee(msr);
626 	(*pr)("%s: %zu valid entries\n", __func__, valid);
627 }
628 
629 static void
630 e500_tlb_walk(void *ctx, bool (*func)(void *, vaddr_t, uint32_t, uint32_t))
631 {
632 	const size_t tlbassoc = TLBCFG_ASSOC(mftlb0cfg());
633 	const size_t tlbentries = TLBCFG_NENTRY(mftlb0cfg());
634 	const size_t max_epn = (tlbentries / tlbassoc) << PAGE_SHIFT;
635 	const uint32_t saved_mas0 = mfspr(SPR_MAS0);
636 
637 	const register_t msr = wrtee(0);
638 	for (size_t assoc = 0; assoc < tlbassoc; assoc++) {
639 		struct e500_hwtlb hwtlb;
640 		hwtlb.hwtlb_mas0 = MAS0_ESEL_MAKE(assoc) | MAS0_TLBSEL_TLB0;
641 		mtspr(SPR_MAS0, hwtlb.hwtlb_mas0);
642 		for (size_t epn = 0; epn < max_epn; epn += PAGE_SIZE) {
643 			mtspr(SPR_MAS2, epn);
644 			__asm volatile("tlbre");
645 			hwtlb.hwtlb_mas1 = mfspr(SPR_MAS1);
646 			if (hwtlb.hwtlb_mas1 & MAS1_V) {
647 				hwtlb.hwtlb_mas2 = mfspr(SPR_MAS2);
648 				hwtlb.hwtlb_mas3 = mfspr(SPR_MAS3);
649 				struct e500_tlb tlb = hwtlb_to_tlb(hwtlb);
650 				if (!(*func)(ctx, tlb.tlb_va, tlb.tlb_asid,
651 				    tlb.tlb_pte))
652 					break;
653 			}
654 		}
655 	}
656 	mtspr(SPR_MAS0, saved_mas0);
657 	wrtee(msr);
658 }
659 
660 static struct e500_xtlb *
661 e500_tlb_lookup_xtlb_pa(vaddr_t pa, u_int *slotp)
662 {
663 	struct e500_tlb1 * const tlb1 = &e500_tlb1;
664 	struct e500_xtlb *xtlb = tlb1->tlb1_entries;
665 
666 	/*
667 	 * See if we have a TLB entry for the pa.
668 	 */
669 	for (u_int i = 0; i < tlb1->tlb1_numentries; i++, xtlb++) {
670 		psize_t mask = ~(xtlb->e_tlb.tlb_size - 1);
671 		if ((xtlb->e_hwtlb.hwtlb_mas1 & MAS1_V)
672 		    && ((pa ^ xtlb->e_tlb.tlb_pte) & mask) == 0) {
673 			if (slotp != NULL)
674 				*slotp = i;
675 			return xtlb;
676 		}
677 	}
678 
679 	return NULL;
680 }
681 
682 struct e500_xtlb *
683 e500_tlb_lookup_xtlb(vaddr_t va, u_int *slotp)
684 {
685 	struct e500_tlb1 * const tlb1 = &e500_tlb1;
686 	struct e500_xtlb *xtlb = tlb1->tlb1_entries;
687 
688 	/*
689 	 * See if we have a TLB entry for the va.
690 	 */
691 	for (u_int i = 0; i < tlb1->tlb1_numentries; i++, xtlb++) {
692 		vsize_t mask = ~(xtlb->e_tlb.tlb_size - 1);
693 		if ((xtlb->e_hwtlb.hwtlb_mas1 & MAS1_V)
694 		    && ((va ^ xtlb->e_tlb.tlb_va) & mask) == 0) {
695 			if (slotp != NULL)
696 				*slotp = i;
697 			return xtlb;
698 		}
699 	}
700 
701 	return NULL;
702 }
703 
704 static struct e500_xtlb *
705 e500_tlb_lookup_xtlb2(vaddr_t va, vsize_t len)
706 {
707 	struct e500_tlb1 * const tlb1 = &e500_tlb1;
708 	struct e500_xtlb *xtlb = tlb1->tlb1_entries;
709 
710 	/*
711 	 * See if we have a TLB entry for the pa.
712 	 */
713 	for (u_int i = 0; i < tlb1->tlb1_numentries; i++, xtlb++) {
714 		vsize_t mask = ~(xtlb->e_tlb.tlb_size - 1);
715 		if ((xtlb->e_hwtlb.hwtlb_mas1 & MAS1_V)
716 		    && ((va ^ xtlb->e_tlb.tlb_va) & mask) == 0
717 		    && (((va + len - 1) ^ va) & mask) == 0) {
718 			return xtlb;
719 		}
720 	}
721 
722 	return NULL;
723 }
724 
725 static void *
726 e500_tlb_mapiodev(paddr_t pa, psize_t len, bool prefetchable)
727 {
728 	struct e500_xtlb * const xtlb = e500_tlb_lookup_xtlb_pa(pa, NULL);
729 
730 	/*
731 	 * See if we have a TLB entry for the pa.  If completely falls within
732 	 * mark the reference and return the pa.  But only if the tlb entry
733 	 * is not cacheable.
734 	 */
735 	if (xtlb
736 	    && (prefetchable
737 		|| (xtlb->e_tlb.tlb_pte & PTE_WIG) == (PTE_I|PTE_G))) {
738 		xtlb->e_refcnt++;
739 		return (void *) (xtlb->e_tlb.tlb_va
740 		    + pa - (xtlb->e_tlb.tlb_pte & PTE_RPN_MASK));
741 	}
742 	return NULL;
743 }
744 
745 static void
746 e500_tlb_unmapiodev(vaddr_t va, vsize_t len)
747 {
748 	if (va < VM_MIN_KERNEL_ADDRESS || VM_MAX_KERNEL_ADDRESS <= va) {
749 		struct e500_xtlb * const xtlb = e500_tlb_lookup_xtlb(va, NULL);
750 		if (xtlb)
751 			xtlb->e_refcnt--;
752 	}
753 }
754 
755 static int
756 e500_tlb_ioreserve(vaddr_t va, vsize_t len, pt_entry_t pte)
757 {
758 	struct e500_tlb1 * const tlb1 = &e500_tlb1;
759 	struct e500_xtlb *xtlb;
760 
761 	KASSERT(len & 0x55555000);
762 	KASSERT((len & ~0x55555000) == 0);
763 	KASSERT(len >= PAGE_SIZE);
764 	KASSERT((len & (len - 1)) == 0);
765 	KASSERT((va & (len - 1)) == 0);
766 	KASSERT(((pte & PTE_RPN_MASK) & (len - 1)) == 0);
767 
768 	if ((xtlb = e500_tlb_lookup_xtlb2(va, len)) != NULL) {
769 		psize_t mask = ~(xtlb->e_tlb.tlb_size - 1);
770 		KASSERT(len <= xtlb->e_tlb.tlb_size);
771 		KASSERT((pte & mask) == (xtlb->e_tlb.tlb_pte & mask));
772 		xtlb->e_refcnt++;
773 		return 0;
774 	}
775 
776 	const int slot = e500_alloc_tlb1_entry();
777 	if (slot < 0)
778 		return ENOMEM;
779 
780 	xtlb = &tlb1->tlb1_entries[slot];
781 	xtlb->e_tlb.tlb_va = va;
782 	xtlb->e_tlb.tlb_size = len;
783 	xtlb->e_tlb.tlb_pte = pte;
784 	xtlb->e_tlb.tlb_asid = KERNEL_PID;
785 
786 	xtlb->e_hwtlb = tlb_to_hwtlb(xtlb->e_tlb);
787 	xtlb->e_hwtlb.hwtlb_mas0 |= __SHIFTIN(slot, MAS0_ESEL);
788 	hwtlb_write(xtlb->e_hwtlb, true);
789 	return 0;
790 }
791 
792 static int
793 e500_tlb_iorelease(vaddr_t va)
794 {
795 	u_int slot;
796 	struct e500_xtlb * const xtlb = e500_tlb_lookup_xtlb(va, &slot);
797 
798 	if (xtlb == NULL)
799 		return ENOENT;
800 
801 	if (xtlb->e_refcnt)
802 		return EBUSY;
803 
804 	e500_free_tlb1_entry(xtlb, slot, true);
805 
806 	return 0;
807 }
808 
809 static u_int
810 e500_tlbmemmap(paddr_t memstart, psize_t memsize, struct e500_tlb1 *tlb1)
811 {
812 	u_int slotmask = 0;
813 	u_int slots = 0, nextslot = 0;
814 	KASSERT(tlb1->tlb1_numfree > 1);
815 	KASSERT(((memstart + memsize - 1) & -memsize) == memstart);
816 	for (paddr_t lastaddr = memstart; 0 < memsize; ) {
817 		u_int cnt = __builtin_clz(memsize);
818 		psize_t size = min(1UL << (31 - (cnt | 1)), tlb1->tlb1_maxsize);
819 		slots += memsize / size;
820 		if (slots > 4)
821 			panic("%s: %d: can't map memory (%#lx) into TLB1: %s",
822 			    __func__, __LINE__, memsize, "too fragmented");
823 		if (slots > tlb1->tlb1_numfree - 1)
824 			panic("%s: %d: can't map memory (%#lx) into TLB1: %s",
825 			    __func__, __LINE__, memsize,
826 			    "insufficent TLB entries");
827 		for (; nextslot < slots; nextslot++) {
828 			const u_int freeslot = e500_alloc_tlb1_entry();
829 			struct e500_xtlb * const xtlb =
830 			    &tlb1->tlb1_entries[freeslot];
831 			xtlb->e_tlb.tlb_asid = KERNEL_PID;
832 			xtlb->e_tlb.tlb_size = size;
833 			xtlb->e_tlb.tlb_va = lastaddr;
834 			xtlb->e_tlb.tlb_pte = lastaddr
835 			    | PTE_M | PTE_xX | PTE_xW | PTE_xR;
836 			lastaddr += size;
837 			memsize -= size;
838 			slotmask |= 1 << (31 - freeslot); /* clz friendly */
839 		}
840 	}
841 
842 	return nextslot;
843 }
844 static const struct tlb_md_ops e500_tlb_ops = {
845 	.md_tlb_get_asid = e500_tlb_get_asid,
846 	.md_tlb_set_asid = e500_tlb_set_asid,
847 	.md_tlb_invalidate_all = e500_tlb_invalidate_all,
848 	.md_tlb_invalidate_globals = e500_tlb_invalidate_globals,
849 	.md_tlb_invalidate_asids = e500_tlb_invalidate_asids,
850 	.md_tlb_invalidate_addr = e500_tlb_invalidate_addr,
851 	.md_tlb_update_addr = e500_tlb_update_addr,
852 	.md_tlb_record_asids = e500_tlb_record_asids,
853 	.md_tlb_write_entry = e500_tlb_write_entry,
854 	.md_tlb_read_entry = e500_tlb_read_entry,
855 	.md_tlb_dump = e500_tlb_dump,
856 	.md_tlb_walk = e500_tlb_walk,
857 };
858 
859 static const struct tlb_md_io_ops e500_tlb_io_ops = {
860 	.md_tlb_mapiodev = e500_tlb_mapiodev,
861 	.md_tlb_unmapiodev = e500_tlb_unmapiodev,
862 	.md_tlb_ioreserve = e500_tlb_ioreserve,
863 	.md_tlb_iorelease = e500_tlb_iorelease,
864 };
865 
866 void
867 e500_tlb_init(vaddr_t endkernel, psize_t memsize)
868 {
869 	struct e500_tlb1 * const tlb1 = &e500_tlb1;
870 
871 #if 0
872 	register_t mmucfg = mfspr(SPR_MMUCFG);
873 	register_t mas4 = mfspr(SPR_MAS4);
874 #endif
875 
876 	const uint32_t tlb1cfg = mftlb1cfg();
877 	tlb1->tlb1_numentries = TLBCFG_NENTRY(tlb1cfg);
878 	KASSERT(tlb1->tlb1_numentries <= __arraycount(tlb1->tlb1_entries));
879 	/*
880 	 * Limit maxsize to 1G since 4G isn't really useful to us.
881 	 */
882 	tlb1->tlb1_minsize = 1024 << (2 * TLBCFG_MINSIZE(tlb1cfg));
883 	tlb1->tlb1_maxsize = 1024 << (2 * min(10, TLBCFG_MAXSIZE(tlb1cfg)));
884 
885 #ifdef VERBOSE_INITPPC
886 	printf(" tlb1cfg=%#x numentries=%u minsize=%#xKB maxsize=%#xKB",
887 	    tlb1cfg, tlb1->tlb1_numentries, tlb1->tlb1_minsize >> 10,
888 	    tlb1->tlb1_maxsize >> 10);
889 #endif
890 
891 	/*
892 	 * Let's see what's in TLB1 and we need to invalidate any entry that
893 	 * would fit within the kernel's mapped address space.
894 	 */
895 	psize_t memmapped = 0;
896 	for (u_int i = 0; i < tlb1->tlb1_numentries; i++) {
897 		struct e500_xtlb * const xtlb = &tlb1->tlb1_entries[i];
898 
899 		xtlb->e_hwtlb = hwtlb_read(MAS0_TLBSEL_TLB1, i);
900 
901 		if ((xtlb->e_hwtlb.hwtlb_mas1 & MAS1_V) == 0) {
902 			tlb1->tlb1_freelist[tlb1->tlb1_numfree++] = i;
903 #ifdef VERBOSE_INITPPC
904 			printf(" TLB1[%u]=<unused>", i);
905 #endif
906 			continue;
907 		}
908 
909 		xtlb->e_tlb = hwtlb_to_tlb(xtlb->e_hwtlb);
910 #ifdef VERBOSE_INITPPC
911 		printf(" TLB1[%u]=<%#lx,%#lx,%#x,%#x>",
912 		    i, xtlb->e_tlb.tlb_va, xtlb->e_tlb.tlb_size,
913 		    xtlb->e_tlb.tlb_asid, xtlb->e_tlb.tlb_pte);
914 #endif
915 		if ((VM_MIN_KERNEL_ADDRESS <= xtlb->e_tlb.tlb_va
916 		    && xtlb->e_tlb.tlb_va < VM_MAX_KERNEL_ADDRESS)
917 		    || (xtlb->e_tlb.tlb_va < VM_MIN_KERNEL_ADDRESS
918 		        && VM_MIN_KERNEL_ADDRESS <
919 			   xtlb->e_tlb.tlb_va + xtlb->e_tlb.tlb_size)) {
920 #ifdef VERBOSE_INITPPC
921 			printf("free");
922 #endif
923 			e500_free_tlb1_entry(xtlb, i, false);
924 #ifdef VERBOSE_INITPPC
925 			printf("d");
926 #endif
927 			continue;
928 		}
929 		if ((xtlb->e_hwtlb.hwtlb_mas1 & MAS1_IPROT) == 0) {
930 			xtlb->e_hwtlb.hwtlb_mas1 |= MAS1_IPROT;
931 			hwtlb_write(xtlb->e_hwtlb, false);
932 #ifdef VERBOSE_INITPPC
933 			printf("+iprot");
934 #endif
935 		}
936 		if (xtlb->e_tlb.tlb_pte & PTE_I)
937 			continue;
938 
939 		if (xtlb->e_tlb.tlb_va == 0
940 		    || xtlb->e_tlb.tlb_va + xtlb->e_tlb.tlb_size <= memsize) {
941 			memmapped += xtlb->e_tlb.tlb_size;
942 			/*
943 			 * Let make sure main memory is setup so it's memory
944 			 * coherent.  For some reason u-boot doesn't set it up
945 			 * that way.
946 			 */
947 			if ((xtlb->e_hwtlb.hwtlb_mas2 & MAS2_M) == 0) {
948 				xtlb->e_hwtlb.hwtlb_mas2 |= MAS2_M;
949 				hwtlb_write(xtlb->e_hwtlb, true);
950 			}
951 		}
952 	}
953 
954 	cpu_md_ops.md_tlb_ops = &e500_tlb_ops;
955 	cpu_md_ops.md_tlb_io_ops = &e500_tlb_io_ops;
956 
957 	if (__predict_false(memmapped < memsize)) {
958 		/*
959 		 * Let's see how many TLB entries are needed to map memory.
960 		 */
961 		u_int slotmask = e500_tlbmemmap(0, memsize, tlb1);
962 
963 		/*
964 		 * To map main memory into the TLB, we need to flush any
965 		 * existing entries from the TLB that overlap the virtual
966 		 * address space needed to map physical memory.  That may
967 		 * include the entries for the pages currently used by the
968 		 * stack or that we are executing.  So to avoid problems, we
969 		 * are going to temporarily map the kernel and stack into AS 1,
970 		 * switch to it, and clear out the TLB entries from AS 0,
971 		 * install the new TLB entries to map memory, and then switch
972 		 * back to AS 0 and free the temp entry used for AS1.
973 		 */
974 		u_int b = __builtin_clz(endkernel);
975 
976 		/*
977 		 * If the kernel doesn't end on a clean power of 2, we need
978 		 * to round the size up (by decrementing the number of leading
979 		 * zero bits).  If the size isn't a power of 4KB, decrement
980 		 * again to make it one.
981 		 */
982 		if (endkernel & (endkernel - 1))
983 			b--;
984 		if ((b & 1) == 0)
985 			b--;
986 
987 		/*
988 		 * Create a TLB1 mapping for the kernel in AS1.
989 		 */
990 		const u_int kslot = e500_alloc_tlb1_entry();
991 		struct e500_xtlb * const kxtlb = &tlb1->tlb1_entries[kslot];
992 		kxtlb->e_tlb.tlb_va = 0;
993 		kxtlb->e_tlb.tlb_size = 1UL << (31 - b);
994 		kxtlb->e_tlb.tlb_pte = PTE_M|PTE_xR|PTE_xW|PTE_xX;
995 		kxtlb->e_tlb.tlb_asid = KERNEL_PID;
996 
997 		kxtlb->e_hwtlb = tlb_to_hwtlb(kxtlb->e_tlb);
998 		kxtlb->e_hwtlb.hwtlb_mas0 |= __SHIFTIN(kslot, MAS0_ESEL);
999 		kxtlb->e_hwtlb.hwtlb_mas1 |= MAS1_TS;
1000 		hwtlb_write(kxtlb->e_hwtlb, true);
1001 
1002 		/*
1003 		 * Now that we have a TLB mapping in AS1 for the kernel and its
1004 		 * stack, we switch to AS1 to cleanup the TLB mappings for TLB0.
1005 		 */
1006 		const register_t saved_msr = mfmsr();
1007 		mtmsr(saved_msr | PSL_DS | PSL_IS);
1008 		__asm volatile("isync");
1009 
1010 		/*
1011 		 *** Invalidate all the TLB0 entries.
1012 		 */
1013 		e500_tlb_invalidate_all();
1014 
1015 		/*
1016 		 *** Now let's see if we have any entries in TLB1 that would
1017 		 *** overlap the ones we are about to install.  If so, nuke 'em.
1018 		 */
1019 		for (u_int i = 0; i < tlb1->tlb1_numentries; i++) {
1020 			struct e500_xtlb * const xtlb = &tlb1->tlb1_entries[i];
1021 			struct e500_hwtlb * const hwtlb = &xtlb->e_hwtlb;
1022 			if ((hwtlb->hwtlb_mas1 & (MAS1_V|MAS1_TS)) == MAS1_V
1023 			    && (hwtlb->hwtlb_mas2 & MAS2_EPN) < memsize) {
1024 				e500_free_tlb1_entry(xtlb, i, false);
1025 			}
1026 		}
1027 
1028 		/*
1029 		 *** Now we can add the TLB entries that will map physical
1030 		 *** memory.  If bit 0 [MSB] in slotmask is set, then tlb
1031 		 *** entry 0 contains a mapping for physical memory...
1032 		 */
1033 		struct e500_xtlb *entries = tlb1->tlb1_entries;
1034 		while (slotmask != 0) {
1035 			const u_int slot = __builtin_clz(slotmask);
1036 			hwtlb_write(entries[slot].e_hwtlb, false);
1037 			entries += slot + 1;
1038 			slotmask <<= slot + 1;
1039 		}
1040 
1041 		/*
1042 		 *** Synchronize the TLB and the instruction stream.
1043 		 */
1044 		__asm volatile("tlbsync");
1045 		__asm volatile("isync");
1046 
1047 		/*
1048 		 *** Switch back to AS 0.
1049 		 */
1050 		mtmsr(saved_msr);
1051 		__asm volatile("isync");
1052 
1053 		/*
1054 		 * Free the temporary TLB1 entry.
1055 		 */
1056 		e500_free_tlb1_entry(kxtlb, kslot, true);
1057 	}
1058 
1059 	/*
1060 	 * Finally set the MAS4 defaults.
1061 	 */
1062 	mtspr(SPR_MAS4, MAS4_TSIZED_4KB | MAS4_MD);
1063 
1064 	/*
1065 	 * Invalidate all the TLB0 entries.
1066 	 */
1067 	e500_tlb_invalidate_all();
1068 }
1069 
1070 void
1071 e500_tlb_minimize(vaddr_t endkernel)
1072 {
1073 #ifdef PMAP_MINIMALTLB
1074 	struct e500_tlb1 * const tlb1 = &e500_tlb1;
1075 	extern uint32_t _fdata[];
1076 
1077 	u_int slot;
1078 
1079 	paddr_t boot_page = cpu_read_4(GUR_BPTR);
1080 	if (boot_page & BPTR_EN) {
1081 		/*
1082 		 * shift it to an address
1083 		 */
1084 		boot_page = (boot_page & BPTR_BOOT_PAGE) << PAGE_SHIFT;
1085 		pmap_kvptefill(boot_page, boot_page + NBPG,
1086 		    PTE_M | PTE_xR | PTE_xW | PTE_xX);
1087 	}
1088 
1089 
1090 	KASSERT(endkernel - (uintptr_t)_fdata < 0x400000);
1091 	KASSERT((uintptr_t)_fdata == 0x400000);
1092 
1093 	struct e500_xtlb *xtlb = e500_tlb_lookup_xtlb(endkernel, &slot);
1094 
1095 	KASSERT(xtlb == e500_tlb_lookup_xtlb2(0, endkernel));
1096 	const u_int tmp_slot = e500_alloc_tlb1_entry();
1097 	KASSERT(tmp_slot != (u_int) -1);
1098 
1099 	struct e500_xtlb * const tmp_xtlb = &tlb1->tlb1_entries[tmp_slot];
1100 	tmp_xtlb->e_tlb = xtlb->e_tlb;
1101 	tmp_xtlb->e_hwtlb = tlb_to_hwtlb(tmp_xtlb->e_tlb);
1102 	tmp_xtlb->e_hwtlb.hwtlb_mas1 |= MAS1_TS;
1103 	KASSERT((tmp_xtlb->e_hwtlb.hwtlb_mas0 & MAS0_TLBSEL) == MAS0_TLBSEL_TLB1);
1104 	tmp_xtlb->e_hwtlb.hwtlb_mas0 |= __SHIFTIN(tmp_slot, MAS0_ESEL);
1105 	hwtlb_write(tmp_xtlb->e_hwtlb, true);
1106 
1107 	const u_int text_slot = e500_alloc_tlb1_entry();
1108 	KASSERT(text_slot != (u_int)-1);
1109 	struct e500_xtlb * const text_xtlb = &tlb1->tlb1_entries[text_slot];
1110 	text_xtlb->e_tlb.tlb_va = 0;
1111 	text_xtlb->e_tlb.tlb_size = 0x400000;
1112 	text_xtlb->e_tlb.tlb_pte = PTE_M | PTE_xR | PTE_xX | text_xtlb->e_tlb.tlb_va;
1113 	text_xtlb->e_tlb.tlb_asid = 0;
1114 	text_xtlb->e_hwtlb = tlb_to_hwtlb(text_xtlb->e_tlb);
1115 	KASSERT((text_xtlb->e_hwtlb.hwtlb_mas0 & MAS0_TLBSEL) == MAS0_TLBSEL_TLB1);
1116 	text_xtlb->e_hwtlb.hwtlb_mas0 |= __SHIFTIN(text_slot, MAS0_ESEL);
1117 
1118 	const u_int data_slot = e500_alloc_tlb1_entry();
1119 	KASSERT(data_slot != (u_int)-1);
1120 	struct e500_xtlb * const data_xtlb = &tlb1->tlb1_entries[data_slot];
1121 	data_xtlb->e_tlb.tlb_va = 0x400000;
1122 	data_xtlb->e_tlb.tlb_size = 0x400000;
1123 	data_xtlb->e_tlb.tlb_pte = PTE_M | PTE_xR | PTE_xW | data_xtlb->e_tlb.tlb_va;
1124 	data_xtlb->e_tlb.tlb_asid = 0;
1125 	data_xtlb->e_hwtlb = tlb_to_hwtlb(data_xtlb->e_tlb);
1126 	KASSERT((data_xtlb->e_hwtlb.hwtlb_mas0 & MAS0_TLBSEL) == MAS0_TLBSEL_TLB1);
1127 	data_xtlb->e_hwtlb.hwtlb_mas0 |= __SHIFTIN(data_slot, MAS0_ESEL);
1128 
1129 	const register_t msr = mfmsr();
1130 	const register_t ts_msr = (msr | PSL_DS | PSL_IS) & ~PSL_EE;
1131 
1132 	__asm __volatile(
1133 		"mtmsr	%[ts_msr]"	"\n\t"
1134 		"sync"			"\n\t"
1135 		"isync"
1136 	    ::	[ts_msr] "r" (ts_msr));
1137 
1138 #if 0
1139 	hwtlb_write(text_xtlb->e_hwtlb, false);
1140 	hwtlb_write(data_xtlb->e_hwtlb, false);
1141 	e500_free_tlb1_entry(xtlb, slot, true);
1142 #endif
1143 
1144 	__asm __volatile(
1145 		"mtmsr	%[msr]"		"\n\t"
1146 		"sync"			"\n\t"
1147 		"isync"
1148 	    ::	[msr] "r" (msr));
1149 
1150 	e500_free_tlb1_entry(tmp_xtlb, tmp_slot, true);
1151 #endif	/* PMAP_MINIMALTLB */
1152 }
1153