ofrom.c revision 1.23 
1/*	$NetBSD: ofrom.c,v 1.23 2011/07/26 08:56:26 mrg Exp $	*/
2
3/*
4 * Copyright 1998
5 * Digital Equipment Corporation. All rights reserved.
6 *
7 * This software is furnished under license and may be used and
8 * copied only in accordance with the following terms and conditions.
9 * Subject to these conditions, you may download, copy, install,
10 * use, modify and distribute this software in source and/or binary
11 * form. No title or ownership is transferred hereby.
12 *
13 * 1) Any source code used, modified or distributed must reproduce
14 *    and retain this copyright notice and list of conditions as
15 *    they appear in the source file.
16 *
17 * 2) No right is granted to use any trade name, trademark, or logo of
18 *    Digital Equipment Corporation. Neither the "Digital Equipment
19 *    Corporation" name nor any trademark or logo of Digital Equipment
20 *    Corporation may be used to endorse or promote products derived
21 *    from this software without the prior written permission of
22 *    Digital Equipment Corporation.
23 *
24 * 3) This software is provided "AS-IS" and any express or implied
25 *    warranties, including but not limited to, any implied warranties
26 *    of merchantability, fitness for a particular purpose, or
27 *    non-infringement are disclaimed. In no event shall DIGITAL be
28 *    liable for any damages whatsoever, and in particular, DIGITAL
29 *    shall not be liable for special, indirect, consequential, or
30 *    incidental damages or damages for lost profits, loss of
31 *    revenue or loss of use, whether such damages arise in contract,
32 *    negligence, tort, under statute, in equity, at law or otherwise,
33 *    even if advised of the possibility of such damage.
34 */
35
36/*
37 * XXX open for writing (for user programs to mmap, and write contents)
38 */
39
40#include <sys/cdefs.h>
41__KERNEL_RCSID(0, "$NetBSD: ofrom.c,v 1.23 2011/07/26 08:56:26 mrg Exp $");
42
43#include <sys/param.h>
44#include <sys/device.h>
45#include <sys/systm.h>
46#include <sys/conf.h>
47#include <sys/fcntl.h>
48#include <sys/bus.h>
49
50#include <uvm/uvm_extern.h>
51
52#include <dev/ofw/openfirm.h>
53
54struct ofrom_softc {
55	int		enabled;
56	paddr_t		base;
57	paddr_t		size;
58};
59
60int ofromprobe(device_t, cfdata_t, void *);
61void ofromattach(device_t, device_t, void *);
62
63CFATTACH_DECL_NEW(ofrom, sizeof(struct ofrom_softc),
64    ofromprobe, ofromattach, NULL, NULL);
65
66extern struct cfdriver ofrom_cd;
67
68dev_type_open(ofromopen);
69dev_type_read(ofromrw);
70dev_type_mmap(ofrommmap);
71
72const struct cdevsw ofrom_cdevsw = {
73	ofromopen, nullclose, ofromrw, ofromrw, noioctl,
74	nostop, notty, nopoll, ofrommmap, nokqfilter,
75};
76
77int
78ofromprobe(device_t parent, cfdata_t cf, void *aux)
79{
80	struct ofbus_attach_args *oba = aux;
81	static const char *const compatible_strings[] = { "rom", NULL };
82
83	return (of_compatible(oba->oba_phandle, compatible_strings) == -1) ?
84	    0 : 5;
85}
86
87
88void
89ofromattach(device_t parent, device_t self, void *aux)
90{
91	struct ofrom_softc *sc = device_private(self);
92	struct ofbus_attach_args *oba = aux;
93	char regbuf[8];
94
95	if (OF_getproplen(oba->oba_phandle, "reg") != 8) {
96		printf(": invalid reg property\n");
97		return;
98	}
99	if (OF_getprop(oba->oba_phandle, "reg", regbuf, sizeof regbuf) != 8) {
100		printf(": couldn't read reg property\n");
101		return;
102	}
103	sc->base = of_decode_int(&regbuf[0]);
104	sc->size = of_decode_int(&regbuf[4]);
105	sc->enabled = 1;
106
107	printf(": %#lx-%#lx\n", sc->base, sc->base + sc->size - 1);
108}
109
110int
111ofromopen(dev_t dev, int oflags, int devtype, struct lwp *l)
112{
113	struct ofrom_softc *sc;
114
115	sc = device_lookup_private(&ofrom_cd, minor(dev));
116	if (!sc || !sc->enabled)
117		return (ENXIO);
118
119	if (oflags & FWRITE)
120		return (EINVAL);
121
122	return (0);
123}
124
125int
126ofromrw(dev_t dev, struct uio *uio, int flags)
127{
128	struct ofrom_softc *sc;
129	int c, error = 0;
130	struct iovec *iov;
131	paddr_t v;
132	psize_t o;
133	extern kmutex_t memlock;
134	extern char *memhook;
135
136	sc = device_lookup_private(&ofrom_cd, minor(dev));
137	if (!sc || !sc->enabled)
138		return (ENXIO);			/* XXX PANIC */
139
140	mutex_enter(&memlock);
141	while (uio->uio_resid > 0 && error == 0) {
142		iov = uio->uio_iov;
143		if (iov->iov_len == 0) {
144			uio->uio_iov++;
145			uio->uio_iovcnt--;
146			if (uio->uio_iovcnt < 0)
147				panic("ofromrw");
148			continue;
149		}
150
151		/*
152		 * Since everything is page aligned and no more
153		 * than the rest of a page is done at once, we
154		 * can just check that the offset isn't too big.
155		 */
156		if (uio->uio_offset >= sc->size)
157			break;
158
159		/* XXX: Use unamanged mapping. */
160		v = sc->base + uio->uio_offset;
161		pmap_enter(pmap_kernel(), (vaddr_t)memhook,
162		    trunc_page(v), uio->uio_rw == UIO_READ ?
163		    VM_PROT_READ : VM_PROT_WRITE, PMAP_WIRED);
164		pmap_update(pmap_kernel());
165		o = uio->uio_offset & PGOFSET;
166		c = min(uio->uio_resid, (int)(PAGE_SIZE - o));
167		error = uiomove((char *)memhook + o, c, uio);
168		pmap_remove(pmap_kernel(), (vaddr_t)memhook,
169		    (vaddr_t)memhook + PAGE_SIZE);
170		pmap_update(pmap_kernel());
171	}
172	mutex_exit(&memlock);
173
174	return (error);
175}
176
177paddr_t
178ofrommmap(dev_t dev, off_t off, int prot)
179{
180	struct ofrom_softc *sc;
181
182	sc = device_lookup_private(&ofrom_cd, minor(dev));
183	if (!sc || !sc->enabled)
184		return (-1);			/* XXX PANIC */
185
186	if ((u_int)off >= sc->size)
187		return (-1);
188
189	return arm_btop(sc->base + off);
190}
191