ofrom.c revision 1.16 
1/*	$NetBSD: ofrom.c,v 1.16 2008/06/11 21:16:28 cegger 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 1.16 2008/06/11 21:16:28 cegger 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
49#include <uvm/uvm_extern.h>
50
51#include <machine/bus.h>
52#include <dev/ofw/openfirm.h>
53
54struct ofrom_softc {
55	struct device	sc_dev;
56	int		enabled;
57	paddr_t		base;
58	paddr_t		size;
59};
60
61int ofromprobe __P((struct device *, struct cfdata *, void *));
62void ofromattach __P((struct device *, struct device *, void *));
63
64CFATTACH_DECL(ofrom, sizeof(struct ofrom_softc),
65    ofromprobe, ofromattach, NULL, NULL);
66
67extern struct cfdriver ofrom_cd;
68
69dev_type_open(ofromopen);
70dev_type_read(ofromrw);
71dev_type_mmap(ofrommmap);
72
73const struct cdevsw ofrom_cdevsw = {
74	ofromopen, nullclose, ofromrw, ofromrw, noioctl,
75	nostop, notty, nopoll, ofrommmap, nokqfilter,
76};
77
78int
79ofromprobe(parent, cf, aux)
80	struct device *parent;
81	struct cfdata *cf;
82	void *aux;
83{
84	struct ofbus_attach_args *oba = aux;
85	static const char *const compatible_strings[] = { "rom", NULL };
86
87	return (of_compatible(oba->oba_phandle, compatible_strings) == -1) ?
88	    0 : 5;
89}
90
91
92void
93ofromattach(parent, self, aux)
94	struct device *parent, *self;
95	void *aux;
96{
97	struct ofrom_softc *sc = (struct ofrom_softc *)self;
98	struct ofbus_attach_args *oba = aux;
99	char regbuf[8];
100
101	if (OF_getproplen(oba->oba_phandle, "reg") != 8) {
102		printf(": invalid reg property\n");
103		return;
104	}
105	if (OF_getprop(oba->oba_phandle, "reg", regbuf, sizeof regbuf) != 8) {
106		printf(": couldn't read reg property\n");
107		return;
108	}
109	sc->base = of_decode_int(&regbuf[0]);
110	sc->size = of_decode_int(&regbuf[4]);
111	sc->enabled = 1;
112
113	printf(": %#lx-%#lx\n", sc->base, sc->base + sc->size - 1);
114}
115
116int
117ofromopen(dev_t dev, int oflags, int devtype, struct lwp *l)
118{
119	struct ofrom_softc *sc;
120
121	sc = device_lookup_private(&ofrom_cd, minor(dev));
122	if (!sc || !sc->enabled)
123		return (ENXIO);
124
125	if (oflags & FWRITE)
126		return (EINVAL);
127
128	return (0);
129}
130
131int
132ofromrw(dev_t dev, struct uio *uio, int flags)
133{
134	struct ofrom_softc *sc;
135	int c, error = 0;
136	struct iovec *iov;
137	paddr_t v;
138	psize_t o;
139	extern int physlock;
140	extern char *memhook;
141
142	sc = device_lookup_private(&ofrom_cd, minor(dev));
143	if (!sc || !sc->enabled)
144		return (ENXIO);			/* XXX PANIC */
145
146	/* lock against other uses of shared vmmap */
147	while (physlock > 0) {
148		physlock++;
149		error = tsleep((void *)&physlock, PZERO | PCATCH, "ofromrw",
150		    0);
151		if (error)
152			return (error);
153	}
154	physlock = 1;
155
156	while (uio->uio_resid > 0 && error == 0) {
157		iov = uio->uio_iov;
158		if (iov->iov_len == 0) {
159			uio->uio_iov++;
160			uio->uio_iovcnt--;
161			if (uio->uio_iovcnt < 0)
162				panic("ofromrw");
163			continue;
164		}
165
166		/*
167		 * Since everything is page aligned and no more
168		 * than the rest of a page is done at once, we
169		 * can just check that the offset isn't too big.
170		 */
171		if (uio->uio_offset >= sc->size)
172			break;
173
174		v = sc->base + uio->uio_offset;
175		pmap_enter(pmap_kernel(), (vaddr_t)memhook,
176		    trunc_page(v), uio->uio_rw == UIO_READ ?
177		    VM_PROT_READ : VM_PROT_WRITE, PMAP_WIRED);
178		pmap_update(pmap_kernel());
179		o = uio->uio_offset & PGOFSET;
180		c = min(uio->uio_resid, (int)(PAGE_SIZE - o));
181		error = uiomove((char *)memhook + o, c, uio);
182		pmap_remove(pmap_kernel(), (vaddr_t)memhook,
183		    (vaddr_t)memhook + PAGE_SIZE);
184		pmap_update(pmap_kernel());
185	}
186
187	if (physlock > 1)
188		wakeup((void *)&physlock);
189	physlock = 0;
190
191	return (error);
192}
193
194paddr_t
195ofrommmap(dev_t dev, off_t off, int prot)
196{
197	struct ofrom_softc *sc;
198
199	sc = device_lookup_private(&ofrom_cd, minor(dev));
200	if (!sc || !sc->enabled)
201		return (-1);			/* XXX PANIC */
202
203	if ((u_int)off >= sc->size)
204		return (-1);
205
206	return arm_btop(sc->base + off);
207}
208