xref: /netbsd-src/sys/arch/powerpc/booke/booke_pmap.c (revision b2c35e17b976cf7ccd7250c86c6f5e95090ed636)
1 /*	$NetBSD: booke_pmap.c,v 1.38 2023/04/17 06:46:53 skrll 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 __KERNEL_RCSID(0, "$NetBSD: booke_pmap.c,v 1.38 2023/04/17 06:46:53 skrll Exp $");
41 
42 #ifdef _KERNEL_OPT
43 #include "opt_multiprocessor.h"
44 #include "opt_pmap.h"
45 #endif
46 
47 #include <sys/param.h>
48 #include <sys/kcore.h>
49 #include <sys/buf.h>
50 #include <sys/mutex.h>
51 
52 #include <uvm/uvm.h>
53 
54 #include <machine/pmap.h>
55 
56 PMAP_COUNTER(zeroed_pages, "pages zeroed");
57 PMAP_COUNTER(copied_pages, "pages copied");
58 
59 CTASSERT(sizeof(pmap_segtab_t) == NBPG);
60 
61 void
62 pmap_procwr(struct proc *p, vaddr_t va, size_t len)
63 {
64 	struct pmap * const pmap = p->p_vmspace->vm_map.pmap;
65 	vsize_t off = va & PAGE_MASK;
66 
67 	kpreempt_disable();
68 	for (const vaddr_t eva = va + len; va < eva; off = 0) {
69 		const vaddr_t segeva = uimin(va + len, va - off + PAGE_SIZE);
70 		pt_entry_t * const ptep = pmap_pte_lookup(pmap, va);
71 		if (ptep == NULL) {
72 			va = segeva;
73 			continue;
74 		}
75 		pt_entry_t pt_entry = *ptep;
76 		if (!pte_valid_p(pt_entry) || !pte_exec_p(pt_entry)) {
77 			va = segeva;
78 			continue;
79 		}
80 		kpreempt_enable();
81 		dcache_wb(pte_to_paddr(pt_entry) + off, segeva - va);
82 		icache_inv(pte_to_paddr(pt_entry) + off, segeva - va);
83 		kpreempt_disable();
84 		va = segeva;
85 	}
86 	kpreempt_enable();
87 }
88 
89 void
90 pmap_md_page_syncicache(struct vm_page_md *mdpg, const kcpuset_t *onproc)
91 {
92 	KASSERT(VM_PAGEMD_VMPAGE_P(mdpg));
93 
94 	struct vm_page * const pg = VM_MD_TO_PAGE(mdpg);
95 
96 	/*
97 	 * If onproc is empty, we could do a
98 	 * pmap_page_protect(pg, VM_PROT_NONE) and remove all
99 	 * mappings of the page and clear its execness.  Then
100 	 * the next time page is faulted, it will get icache
101 	 * synched.  But this is easier. :)
102 	 */
103 	const paddr_t pa = VM_PAGE_TO_PHYS(pg);
104 	dcache_wb_page(pa);
105 	icache_inv_page(pa);
106 }
107 
108 vaddr_t
109 pmap_md_direct_map_paddr(paddr_t pa)
110 {
111 	return (vaddr_t) pa;
112 }
113 
114 bool
115 pmap_md_direct_mapped_vaddr_p(vaddr_t va)
116 {
117 	return va < VM_MIN_KERNEL_ADDRESS || VM_MAX_KERNEL_ADDRESS <= va;
118 }
119 
120 paddr_t
121 pmap_md_direct_mapped_vaddr_to_paddr(vaddr_t va)
122 {
123 	return (paddr_t) va;
124 }
125 
126 #ifdef PMAP_MINIMALTLB
127 static pt_entry_t *
128 kvtopte(const pmap_segtab_t *stb, vaddr_t va)
129 {
130 	pt_entry_t * const ptep = stb->seg_tab[va >> SEGSHIFT];
131 	if (ptep == NULL)
132 		return NULL;
133 	return &ptep[(va & SEGOFSET) >> PAGE_SHIFT];
134 }
135 
136 vaddr_t
137 pmap_kvptefill(vaddr_t sva, vaddr_t eva, pt_entry_t pt_entry)
138 {
139 	pmap_segtab_t * const stb = &pmap_kern_segtab;
140 	KASSERT(sva == trunc_page(sva));
141 	pt_entry_t *ptep = kvtopte(stb, sva);
142 	for (; sva < eva; sva += NBPG) {
143 		*ptep++ = pt_entry ? (sva | pt_entry) : 0;
144 	}
145 	return sva;
146 }
147 #endif
148 
149 /*
150  *	Bootstrap the system enough to run with virtual memory.
151  *	firstaddr is the first unused kseg0 address (not page aligned).
152  */
153 vaddr_t
154 pmap_bootstrap(vaddr_t startkernel, vaddr_t endkernel,
155 	phys_ram_seg_t *avail, size_t cnt)
156 {
157 	pmap_segtab_t * const stp = &pmap_kern_segtab;
158 
159 	KASSERT(endkernel == trunc_page(endkernel));
160 
161 	/* common initialization */
162 	pmap_bootstrap_common();
163 
164 	/* init the lock */
165 	pmap_tlb_info_init(&pmap_tlb0_info);
166 
167 	/*
168 	 * Compute the number of pages kmem_arena will have.
169 	 */
170 	kmeminit_nkmempages();
171 
172 	/*
173 	 * Figure out how many PTE's are necessary to map the kernel.
174 	 * We also reserve space for kmem_alloc_pageable() for vm_fork().
175 	 */
176 
177 	/* Get size of buffer cache and set an upper limit */
178 	buf_setvalimit((VM_MAX_KERNEL_ADDRESS - VM_MIN_KERNEL_ADDRESS) / 8);
179 	vsize_t bufsz = buf_memcalc();
180 	buf_setvalimit(bufsz);
181 
182 	vsize_t kv_nsegtabs = pmap_round_seg(VM_PHYS_SIZE
183 	    + (ubc_nwins << ubc_winshift)
184 	    + bufsz
185 	    + 16 * NCARGS
186 	    + pager_map_size
187 	    + maxproc * USPACE
188 	    + NBPG * nkmempages) >> SEGSHIFT;
189 
190 	/*
191 	 * Initialize `FYI' variables.	Note we're relying on
192 	 * the fact that BSEARCH sorts the vm_physmem[] array
193 	 * for us.  Must do this before uvm_pageboot_alloc()
194 	 * can be called.
195 	 */
196 	pmap_limits.avail_start = uvm_physseg_get_start(uvm_physseg_get_first()) << PGSHIFT;
197 	pmap_limits.avail_end = uvm_physseg_get_end(uvm_physseg_get_last()) << PGSHIFT;
198 	const size_t max_nsegtabs =
199 	    (pmap_round_seg(VM_MAX_KERNEL_ADDRESS)
200 		- pmap_trunc_seg(VM_MIN_KERNEL_ADDRESS)) / NBSEG;
201 	if (kv_nsegtabs >= max_nsegtabs) {
202 		pmap_limits.virtual_end = VM_MAX_KERNEL_ADDRESS;
203 		kv_nsegtabs = max_nsegtabs;
204 	} else {
205 		pmap_limits.virtual_end = VM_MIN_KERNEL_ADDRESS
206 		    + kv_nsegtabs * NBSEG;
207 	}
208 
209 	/* update the top of the kernel VM - pmap_growkernel not required */
210 	pmap_curmaxkvaddr = pmap_limits.virtual_end;
211 
212 	/*
213 	 * Now actually allocate the kernel PTE array (must be done
214 	 * after virtual_end is initialized).
215 	 */
216 	const vaddr_t kv_segtabs = avail[0].start;
217 	KASSERT(kv_segtabs == endkernel);
218 	KASSERT(avail[0].size >= NBPG * kv_nsegtabs);
219 	printf(" kv_nsegtabs=%#"PRIxVSIZE, kv_nsegtabs);
220 	printf(" kv_segtabs=%#"PRIxVADDR, kv_segtabs);
221 	avail[0].start += NBPG * kv_nsegtabs;
222 	avail[0].size -= NBPG * kv_nsegtabs;
223 	endkernel += NBPG * kv_nsegtabs;
224 
225 	/*
226 	 * Initialize the kernel's two-level page level.  This only wastes
227 	 * an extra page for the segment table and allows the user/kernel
228 	 * access to be common.
229 	 */
230 
231 	pmap_ptpage_t **ppg_p = &stp->seg_ppg[VM_MIN_KERNEL_ADDRESS >> SEGSHIFT];
232 	pmap_ptpage_t *ppg = (void *)kv_segtabs;
233 	memset(ppg, 0, NBPG * kv_nsegtabs);
234 	for (size_t i = 0; i < kv_nsegtabs; i++, ppg++) {
235 		*ppg_p++ = ppg;
236 	}
237 
238 #if PMAP_MINIMALTLB
239 	const vsize_t dm_nsegtabs = (physmem + NPTEPG - 1) / NPTEPG;
240 	const vaddr_t dm_segtabs = avail[0].start;
241 	printf(" dm_nsegtabs=%#"PRIxVSIZE, dm_nsegtabs);
242 	printf(" dm_segtabs=%#"PRIxVADDR, dm_segtabs);
243 	KASSERT(dm_segtabs == endkernel);
244 	KASSERT(avail[0].size >= NBPG * dm_nsegtabs);
245 	avail[0].start += NBPG * dm_nsegtabs;
246 	avail[0].size -= NBPG * dm_nsegtabs;
247 	endkernel += NBPG * dm_nsegtabs;
248 
249 	ptp = stp->seg_tab;
250 	ppg = (void *)dm_segtabs;
251 	memset(ppg, 0, NBPG * dm_nsegtabs);
252 	for (size_t i = 0; i < dm_nsegtabs; i++, ptp++, ppg++) {
253 		*ptp = ppg;
254 	}
255 
256 	/*
257 	 */
258 	extern uint32_t _fdata[], _etext[];
259 	vaddr_t va;
260 
261 	/* Now make everything before the kernel inaccessible. */
262 	va = pmap_kvptefill(NBPG, startkernel, 0);
263 
264 	/* Kernel text is readonly & executable */
265 	va = pmap_kvptefill(va, round_page((vaddr_t)_etext),
266 	    PTE_M | PTE_xR | PTE_xX);
267 
268 	/* Kernel .rdata is readonly */
269 	va = pmap_kvptefill(va, trunc_page((vaddr_t)_fdata), PTE_M | PTE_xR);
270 
271 	/* Kernel .data/.bss + page tables are read-write */
272 	va = pmap_kvptefill(va, round_page(endkernel), PTE_M | PTE_xR | PTE_xW);
273 
274 	/* message buffer page table pages are read-write */
275 	(void) pmap_kvptefill(msgbuf_paddr, msgbuf_paddr+round_page(MSGBUFSIZE),
276 	    PTE_M | PTE_xR | PTE_xW);
277 #endif
278 
279 	for (size_t i = 0; i < cnt; i++) {
280 		printf(" uvm_page_physload(%#lx,%#lx,%#lx,%#lx,%d)",
281 		    atop(avail[i].start),
282 		    atop(avail[i].start + avail[i].size) - 1,
283 		    atop(avail[i].start),
284 		    atop(avail[i].start + avail[i].size) - 1,
285 		    VM_FREELIST_DEFAULT);
286 		uvm_page_physload(
287 		    atop(avail[i].start),
288 		    atop(avail[i].start + avail[i].size) - 1,
289 		    atop(avail[i].start),
290 		    atop(avail[i].start + avail[i].size) - 1,
291 		    VM_FREELIST_DEFAULT);
292 	}
293 
294 	pmap_pvlist_lock_init(curcpu()->ci_ci.dcache_line_size);
295 
296 	/*
297 	 * Initialize the pools.
298 	 */
299 	pool_init(&pmap_pmap_pool, PMAP_SIZE, 0, 0, 0, "pmappl",
300 	    &pool_allocator_nointr, IPL_NONE);
301 	pool_init(&pmap_pv_pool, sizeof(struct pv_entry), 0, 0, 0, "pvpl",
302 	    &pmap_pv_page_allocator, IPL_NONE);
303 
304 	tlb_set_asid(KERNEL_PID, pmap_kernel());
305 
306 	return endkernel;
307 }
308 
309 struct vm_page *
310 pmap_md_alloc_poolpage(int flags)
311 {
312 
313 	/*
314 	 * Any managed page works for us.
315 	 */
316 	return uvm_pagealloc(NULL, 0, NULL, flags);
317 }
318 
319 vaddr_t
320 pmap_md_map_poolpage(paddr_t pa, vsize_t size)
321 {
322 	const vaddr_t sva = (vaddr_t) pa;
323 #ifdef PMAP_MINIMALTLB
324 	const vaddr_t eva = sva + size;
325 	pmap_kvptefill(sva, eva, PTE_M | PTE_xR | PTE_xW);
326 #endif
327 	return sva;
328 }
329 
330 void
331 pmap_md_unmap_poolpage(vaddr_t va, vsize_t size)
332 {
333 #ifdef PMAP_MINIMALTLB
334 	struct pmap * const pm = pmap_kernel();
335 	const vaddr_t eva = va + size;
336 	pmap_kvptefill(va, eva, 0);
337 	for (;va < eva; va += NBPG) {
338 		pmap_tlb_invalidate_addr(pm, va);
339 	}
340 	pmap_update(pm);
341 #endif
342 }
343 
344 void
345 pmap_zero_page(paddr_t pa)
346 {
347 	PMAP_COUNT(zeroed_pages);
348 	vaddr_t va = pmap_md_map_poolpage(pa, NBPG);
349 	dcache_zero_page(va);
350 
351 	KASSERT(!VM_PAGEMD_EXECPAGE_P(VM_PAGE_TO_MD(PHYS_TO_VM_PAGE(va))));
352 	pmap_md_unmap_poolpage(va, NBPG);
353 }
354 
355 void
356 pmap_copy_page(paddr_t src, paddr_t dst)
357 {
358 	const size_t line_size = curcpu()->ci_ci.dcache_line_size;
359 	vaddr_t src_va = pmap_md_map_poolpage(src, NBPG);
360 	vaddr_t dst_va = pmap_md_map_poolpage(dst, NBPG);
361 	const vaddr_t end = src_va + PAGE_SIZE;
362 
363 	PMAP_COUNT(copied_pages);
364 
365 	while (src_va < end) {
366 		__asm __volatile(
367 			"dcbt	%2,%0"	"\n\t"	/* touch next src cacheline */
368 			"dcba	0,%1"	"\n\t" 	/* don't fetch dst cacheline */
369 		    :: "b"(src_va), "b"(dst_va), "b"(line_size));
370 		for (u_int i = 0;
371 		     i < line_size;
372 		     src_va += 32, dst_va += 32, i += 32) {
373 			register_t tmp;
374 			__asm __volatile(
375 				"mr	%[tmp],31"	"\n\t"
376 				"lmw	24,0(%[src])"	"\n\t"
377 				"stmw	24,0(%[dst])"	"\n\t"
378 				"mr	31,%[tmp]"	"\n\t"
379 			    : [tmp] "=&r"(tmp)
380 			    : [src] "b"(src_va), [dst] "b"(dst_va)
381 			    : "r24", "r25", "r26", "r27",
382 			      "r28", "r29", "r30", "memory");
383 		}
384 	}
385 	pmap_md_unmap_poolpage(src_va, NBPG);
386 	pmap_md_unmap_poolpage(dst_va, NBPG);
387 
388 	KASSERT(!VM_PAGEMD_EXECPAGE_P(VM_PAGE_TO_MD(PHYS_TO_VM_PAGE(dst))));
389 }
390 
391 void
392 pmap_md_init(void)
393 {
394 
395 	/* nothing for now */
396 }
397 
398 bool
399 pmap_md_io_vaddr_p(vaddr_t va)
400 {
401 	return va >= pmap_limits.avail_end
402 	    && !(VM_MIN_KERNEL_ADDRESS <= va && va < VM_MAX_KERNEL_ADDRESS);
403 }
404 
405 bool
406 pmap_md_tlb_check_entry(void *ctx, vaddr_t va, tlb_asid_t asid, pt_entry_t pte)
407 {
408 	pmap_t pm = ctx;
409 	struct pmap_asid_info * const pai = PMAP_PAI(pm, curcpu()->ci_tlb_info);
410 
411 	if (asid != pai->pai_asid)
412 		return true;
413 
414 	const pt_entry_t * const ptep = pmap_pte_lookup(pm, va);
415 	KASSERT(ptep != NULL);
416 	pt_entry_t xpte = *ptep;
417 	xpte &= ~((xpte & (PTE_UNSYNCED|PTE_UNMODIFIED)) << 1);
418 	xpte ^= xpte & (PTE_UNSYNCED|PTE_UNMODIFIED|PTE_WIRED);
419 
420 	KASSERTMSG(pte == xpte,
421 	    "pm=%p va=%#"PRIxVADDR" asid=%u: TLB pte (%#x) != real pte (%#x/%#x)",
422 	    pm, va, asid, pte, xpte, *ptep);
423 
424 	return true;
425 }
426 
427 #ifdef MULTIPROCESSOR
428 void
429 pmap_md_tlb_info_attach(struct pmap_tlb_info *ti, struct cpu_info *ci)
430 {
431 	/* nothing */
432 }
433 #endif /* MULTIPROCESSOR */
434