1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2005 Olivier Houchard
5 * Copyright (c) 1989, 1992, 1993
6 *	The Regents of the University of California.  All rights reserved.
7 *
8 * This code is derived from software developed by the Computer Systems
9 * Engineering group at Lawrence Berkeley Laboratory under DARPA contract
10 * BG 91-66 and contributed to Berkeley.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 *    notice, this list of conditions and the following disclaimer in the
19 *    documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
29 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
30 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
31 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
32 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
33 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36/*
37 * ARM machine dependent routines for kvm.
38 */
39
40#include <sys/cdefs.h>
41__FBSDID("$FreeBSD$");
42
43#include <sys/param.h>
44#include <sys/endian.h>
45#include <kvm.h>
46#include <limits.h>
47#include <stdint.h>
48#include <stdlib.h>
49#include <unistd.h>
50
51#ifdef __arm__
52#include <machine/vmparam.h>
53#endif
54
55#include "kvm_private.h"
56#include "kvm_arm.h"
57
58struct vmstate {
59	arm_pd_entry_t *l1pt;
60	size_t phnum;
61	GElf_Phdr *phdr;
62};
63
64/*
65 * Translate a physical memory address to a file-offset in the crash-dump.
66 */
67static size_t
68_kvm_pa2off(kvm_t *kd, uint64_t pa, off_t *ofs, size_t pgsz)
69{
70	struct vmstate *vm = kd->vmst;
71	GElf_Phdr *p;
72	size_t n;
73
74	p = vm->phdr;
75	n = vm->phnum;
76	while (n && (pa < p->p_paddr || pa >= p->p_paddr + p->p_memsz))
77		p++, n--;
78	if (n == 0)
79		return (0);
80
81	*ofs = (pa - p->p_paddr) + p->p_offset;
82	if (pgsz == 0)
83		return (p->p_memsz - (pa - p->p_paddr));
84	return (pgsz - ((size_t)pa & (pgsz - 1)));
85}
86
87static void
88_arm_freevtop(kvm_t *kd)
89{
90	struct vmstate *vm = kd->vmst;
91
92	free(vm->phdr);
93	free(vm);
94	kd->vmst = NULL;
95}
96
97static int
98_arm_probe(kvm_t *kd)
99{
100
101	return (_kvm_probe_elf_kernel(kd, ELFCLASS32, EM_ARM) &&
102	    !_kvm_is_minidump(kd));
103}
104
105static int
106_arm_initvtop(kvm_t *kd)
107{
108	struct vmstate *vm;
109	struct kvm_nlist nl[2];
110	kvaddr_t kernbase;
111	arm_physaddr_t physaddr, pa;
112	arm_pd_entry_t *l1pt;
113	size_t i;
114	int found;
115
116	if (kd->rawdump) {
117		_kvm_err(kd, kd->program, "raw dumps not supported on arm");
118		return (-1);
119	}
120
121	vm = _kvm_malloc(kd, sizeof(*vm));
122	if (vm == NULL) {
123		_kvm_err(kd, kd->program, "cannot allocate vm");
124		return (-1);
125	}
126	kd->vmst = vm;
127	vm->l1pt = NULL;
128
129	if (_kvm_read_core_phdrs(kd, &vm->phnum, &vm->phdr) == -1)
130		return (-1);
131
132	found = 0;
133	for (i = 0; i < vm->phnum; i++) {
134		if (vm->phdr[i].p_type == PT_DUMP_DELTA) {
135			kernbase = vm->phdr[i].p_vaddr;
136			physaddr = vm->phdr[i].p_paddr;
137			found = 1;
138			break;
139		}
140	}
141
142	nl[1].n_name = NULL;
143	if (!found) {
144		nl[0].n_name = "kernbase";
145		if (kvm_nlist2(kd, nl) != 0) {
146#ifdef __arm__
147			kernbase = KERNBASE;
148#else
149		_kvm_err(kd, kd->program, "cannot resolve kernbase");
150		return (-1);
151#endif
152		} else
153			kernbase = nl[0].n_value;
154
155		nl[0].n_name = "physaddr";
156		if (kvm_nlist2(kd, nl) != 0) {
157			_kvm_err(kd, kd->program, "couldn't get phys addr");
158			return (-1);
159		}
160		physaddr = nl[0].n_value;
161	}
162	nl[0].n_name = "kernel_l1pa";
163	if (kvm_nlist2(kd, nl) != 0) {
164		_kvm_err(kd, kd->program, "bad namelist");
165		return (-1);
166	}
167	if (kvm_read2(kd, (nl[0].n_value - kernbase + physaddr), &pa,
168	    sizeof(pa)) != sizeof(pa)) {
169		_kvm_err(kd, kd->program, "cannot read kernel_l1pa");
170		return (-1);
171	}
172	l1pt = _kvm_malloc(kd, ARM_L1_TABLE_SIZE);
173	if (l1pt == NULL) {
174		_kvm_err(kd, kd->program, "cannot allocate l1pt");
175		return (-1);
176	}
177	if (kvm_read2(kd, pa, l1pt, ARM_L1_TABLE_SIZE) != ARM_L1_TABLE_SIZE) {
178		_kvm_err(kd, kd->program, "cannot read l1pt");
179		free(l1pt);
180		return (-1);
181	}
182	vm->l1pt = l1pt;
183	return 0;
184}
185
186/* from arm/pmap.c */
187#define	ARM_L1_IDX(va)		((va) >> ARM_L1_S_SHIFT)
188
189#define	l1pte_section_p(pde)	(((pde) & ARM_L1_TYPE_MASK) == ARM_L1_TYPE_S)
190#define	l1pte_valid(pde)	((pde) != 0)
191#define	l2pte_valid(pte)	((pte) != 0)
192#define l2pte_index(v)		(((v) & ARM_L1_S_OFFSET) >> ARM_L2_S_SHIFT)
193
194
195static int
196_arm_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
197{
198	struct vmstate *vm = kd->vmst;
199	arm_pd_entry_t pd;
200	arm_pt_entry_t pte;
201	arm_physaddr_t pte_pa;
202	off_t pte_off;
203
204	if (vm->l1pt == NULL)
205		return (_kvm_pa2off(kd, va, pa, ARM_PAGE_SIZE));
206	pd = _kvm32toh(kd, vm->l1pt[ARM_L1_IDX(va)]);
207	if (!l1pte_valid(pd))
208		goto invalid;
209	if (l1pte_section_p(pd)) {
210		/* 1MB section mapping. */
211		*pa = (pd & ARM_L1_S_ADDR_MASK) + (va & ARM_L1_S_OFFSET);
212		return  (_kvm_pa2off(kd, *pa, pa, ARM_L1_S_SIZE));
213	}
214	pte_pa = (pd & ARM_L1_C_ADDR_MASK) + l2pte_index(va) * sizeof(pte);
215	_kvm_pa2off(kd, pte_pa, &pte_off, ARM_L1_S_SIZE);
216	if (pread(kd->pmfd, &pte, sizeof(pte), pte_off) != sizeof(pte)) {
217		_kvm_syserr(kd, kd->program, "_arm_kvatop: pread");
218		goto invalid;
219	}
220	pte = _kvm32toh(kd, pte);
221	if (!l2pte_valid(pte)) {
222		goto invalid;
223	}
224	if ((pte & ARM_L2_TYPE_MASK) == ARM_L2_TYPE_L) {
225		*pa = (pte & ARM_L2_L_FRAME) | (va & ARM_L2_L_OFFSET);
226		return (_kvm_pa2off(kd, *pa, pa, ARM_L2_L_SIZE));
227	}
228	*pa = (pte & ARM_L2_S_FRAME) | (va & ARM_L2_S_OFFSET);
229	return (_kvm_pa2off(kd, *pa, pa, ARM_PAGE_SIZE));
230invalid:
231	_kvm_err(kd, 0, "Invalid address (%jx)", (uintmax_t)va);
232	return 0;
233}
234
235/*
236 * Machine-dependent initialization for ALL open kvm descriptors,
237 * not just those for a kernel crash dump.  Some architectures
238 * have to deal with these NOT being constants!  (i.e. m68k)
239 */
240#ifdef FBSD_NOT_YET
241int
242_kvm_mdopen(kvm_t *kd)
243{
244
245	kd->usrstack = USRSTACK;
246	kd->min_uva = VM_MIN_ADDRESS;
247	kd->max_uva = VM_MAXUSER_ADDRESS;
248
249	return (0);
250}
251#endif
252
253int
254#ifdef __arm__
255_arm_native(kvm_t *kd)
256#else
257_arm_native(kvm_t *kd __unused)
258#endif
259{
260
261#ifdef __arm__
262#if _BYTE_ORDER == _LITTLE_ENDIAN
263	return (kd->nlehdr.e_ident[EI_DATA] == ELFDATA2LSB);
264#else
265	return (kd->nlehdr.e_ident[EI_DATA] == ELFDATA2MSB);
266#endif
267#else
268	return (0);
269#endif
270}
271
272static struct kvm_arch kvm_arm = {
273	.ka_probe = _arm_probe,
274	.ka_initvtop = _arm_initvtop,
275	.ka_freevtop = _arm_freevtop,
276	.ka_kvatop = _arm_kvatop,
277	.ka_native = _arm_native,
278};
279
280KVM_ARCH(kvm_arm);
281