1/* $NetBSD: kvm_mips.c,v 1.20 2010/09/20 23:23:16 jym Exp $ */
2
3/*
4 * Copyright (c) 1994, 1995 Carnegie-Mellon University.
5 * All rights reserved.
6 *
7 * Author: Chris G. Demetriou
8 *
9 * Permission to use, copy, modify and distribute this software and
10 * its documentation is hereby granted, provided that both the copyright
11 * notice and this permission notice appear in all copies of the
12 * software, derivative works or modified versions, and any portions
13 * thereof, and that both notices appear in supporting documentation.
14 *
15 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
16 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
17 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
18 *
19 * Carnegie Mellon requests users of this software to return to
20 *
21 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
22 *  School of Computer Science
23 *  Carnegie Mellon University
24 *  Pittsburgh PA 15213-3890
25 *
26 * any improvements or extensions that they make and grant Carnegie the
27 * rights to redistribute these changes.
28 */
29
30/*
31 * Modified for NetBSD/mips by Jason R. Thorpe, Numerical Aerospace
32 * Simulation Facility, NASA Ames Research Center.
33 */
34
35#include <sys/cdefs.h>
36#if defined(LIBC_SCCS) && !defined(lint)
37__RCSID("$NetBSD: kvm_mips.c,v 1.20 2010/09/20 23:23:16 jym Exp $");
38#endif /* LIBC_SCCS and not lint */
39
40/*
41 * MIPS machine dependent routines for kvm.
42 */
43
44#include <sys/param.h>
45#include <sys/user.h>
46#include <sys/proc.h>
47#include <sys/stat.h>
48#include <sys/kcore.h>
49#include <sys/types.h>
50
51#include <machine/kcore.h>
52
53#include <stdlib.h>
54#include <unistd.h>
55#include <nlist.h>
56#include <kvm.h>
57
58#include <uvm/uvm_extern.h>
59
60#include <limits.h>
61#include <db.h>
62
63#include "kvm_private.h"
64
65#include <mips/cpuregs.h>
66#include <mips/vmparam.h>
67
68void
69_kvm_freevtop(kvm_t *kd)
70{
71
72	/* Not actually used for anything right now, but safe. */
73	if (kd->vmst != 0)
74		free(kd->vmst);
75}
76
77int
78_kvm_initvtop(kvm_t *kd)
79{
80
81	return (0);
82}
83
84/*
85 * Translate a kernel virtual address to a physical address.
86 */
87int
88_kvm_kvatop(kvm_t *kd, vaddr_t va, paddr_t *pa)
89{
90	cpu_kcore_hdr_t *cpu_kh;
91	int page_off;
92	u_int pte;
93	paddr_t pte_pa;
94
95	if (ISALIVE(kd)) {
96		_kvm_err(kd, 0, "vatop called in live kernel!");
97		return((off_t)0);
98	}
99
100	cpu_kh = kd->cpu_data;
101	page_off = va & PGOFSET;
102
103#ifdef _LP64
104	if (MIPS_XKPHYS_P(va)) {
105		/*
106		 * Direct-mapped cached address: just convert it.
107		 */
108		*pa = MIPS_XKPHYS_TO_PHYS(va);
109		return (NBPG - page_off);
110	}
111
112	if (va < MIPS_XKPHYS_START) {
113		/*
114		 * XUSEG (user virtual address space) - invalid.
115		 */
116		_kvm_err(kd, 0, "invalid kernel virtual address");
117		goto lose;
118	}
119#else
120	if (va < MIPS_KSEG0_START) {
121		/*
122		 * KUSEG (user virtual address space) - invalid.
123		 */
124		_kvm_err(kd, 0, "invalid kernel virtual address");
125		goto lose;
126	}
127#endif
128
129	if (MIPS_KSEG0_P(va)) {
130		/*
131		 * Direct-mapped cached address: just convert it.
132		 */
133		*pa = MIPS_KSEG0_TO_PHYS(va);
134		return (NBPG - page_off);
135	}
136
137	if (MIPS_KSEG1_P(va)) {
138		/*
139		 * Direct-mapped uncached address: just convert it.
140		 */
141		*pa = MIPS_KSEG1_TO_PHYS(va);
142		return (NBPG - page_off);
143	}
144
145#ifdef _LP64
146	if (va >= MIPS_KSEG2_START) {
147		/*
148		 * KUSEG (user virtual address space) - invalid.
149		 */
150		_kvm_err(kd, 0, "invalid kernel virtual address");
151		goto lose;
152	}
153#endif
154
155	/*
156	 * We now know that we're a KSEG2 (kernel virtually mapped)
157	 * address.  Translate the address using the pmap's kernel
158	 * page table.
159	 */
160
161	/*
162	 * Step 1: Make sure the kernel page table has a translation
163	 * for the address.
164	 */
165#ifdef _LP64
166	if (va >= (MIPS_XKSEG_START + (cpu_kh->sysmapsize * NBPG))) {
167		_kvm_err(kd, 0, "invalid XKSEG address");
168		goto lose;
169	}
170#else
171	if (va >= (MIPS_KSEG2_START + (cpu_kh->sysmapsize * NBPG))) {
172		_kvm_err(kd, 0, "invalid KSEG2 address");
173		goto lose;
174	}
175#endif
176
177	/*
178	 * Step 2: Locate and read the PTE.
179	 */
180	pte_pa = cpu_kh->sysmappa +
181	    (((va - MIPS_KSEG2_START) >> PGSHIFT) * sizeof(u_int));
182	if (_kvm_pread(kd, kd->pmfd, &pte, sizeof(pte),
183	    _kvm_pa2off(kd, pte_pa)) != sizeof(pte)) {
184		_kvm_syserr(kd, 0, "could not read PTE");
185		goto lose;
186	}
187
188	/*
189	 * Step 3: Validate the PTE and return the physical address.
190	 */
191	if ((pte & cpu_kh->pg_v) == 0) {
192		_kvm_err(kd, 0, "invalid translation (invalid PTE)");
193		goto lose;
194	}
195	*pa = (((pte & cpu_kh->pg_frame) >> cpu_kh->pg_shift) << PGSHIFT) +
196	    page_off;
197	return (NBPG - page_off);
198
199 lose:
200	*pa = -1;
201	return (0);
202}
203
204/*
205 * Translate a physical address to a file-offset in the crash dump.
206 */
207off_t
208_kvm_pa2off(kvm_t *kd, paddr_t pa)
209{
210	cpu_kcore_hdr_t *cpu_kh;
211	phys_ram_seg_t *ramsegs;
212	off_t off;
213	int i;
214
215	cpu_kh = kd->cpu_data;
216	ramsegs = (phys_ram_seg_t *)((char *)cpu_kh + ALIGN(sizeof *cpu_kh));
217
218	off = 0;
219	for (i = 0; i < cpu_kh->nmemsegs; i++) {
220		if (pa >= ramsegs[i].start &&
221		    (pa - ramsegs[i].start) < ramsegs[i].size) {
222			off += (pa - ramsegs[i].start);
223			break;
224		}
225		off += ramsegs[i].size;
226	}
227
228	return (kd->dump_off + off);
229}
230
231/*
232 * Machine-dependent initialization for ALL open kvm descriptors,
233 * not just those for a kernel crash dump.  Some architectures
234 * have to deal with these NOT being constants!  (i.e. m68k)
235 */
236int
237_kvm_mdopen(kvm_t *kd)
238{
239
240	kd->usrstack = USRSTACK;
241	kd->min_uva = VM_MIN_ADDRESS;
242	kd->max_uva = VM_MAXUSER_ADDRESS;
243
244	return (0);
245}
246