1/*-
2 * Copyright (c) 2020 Justin Hibbits
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include <sys/cdefs.h>
27__FBSDID("$FreeBSD$");
28
29#include <sys/param.h>
30#include <sys/systm.h>
31#include <sys/conf.h>
32#include <sys/kernel.h>
33#include <sys/bus.h>
34#include <sys/limits.h>
35#include <sys/module.h>
36#include <sys/malloc.h>
37#include <sys/mutex.h>
38#include <sys/rman.h>
39#include <sys/sysctl.h>
40
41#include <machine/bus.h>
42
43#include <dev/ofw/ofw_bus.h>
44#include <dev/ofw/ofw_bus_subr.h>
45
46#include <sys/kdb.h>
47
48#include "cpld.h"
49
50/*
51 * A driver for the AmigaOne A1222 "Tabor" Main CPLD.
52 *
53 * The main CPLD is the interface between the CPU and the GPIO CPLD.
54 * Communication with the GPIO CPLD is over the main CPLD's mailbox interface,
55 * along with the dual-port RAM on the CPLD.
56 *
57 * Only one process can open the CPLD character device at a time.  The driver
58 * enforces this to simplify the communication protocol.
59 */
60
61/* Resource access addresses. */
62#define	CPLD_MEM_ADDR_H		0x00
63#define	CPLD_MEM_ADDR_L		0x01
64#define	CPLD_MEM_DATA		0x80
65
66#define	CPLD_MAX_DRAM_WORDS	0x800
67
68/* CPLD Registers. */
69#define	CPLD_REG_SIG1		0x00
70#define	CPLD_REG_SIG2		0x01
71#define	CPLD_REG_HWREV		0x02
72#define	CPLD_REG_CPLDREV	0x03
73#define	CPLD_REG_MBC2X		0x04
74#define	CPLD_REG_MBX2C		0x05
75#define	CPLD_REG_FAN1_TACHO_U	0x10
76#define	CPLD_REG_FAN1_TACHO_L	0x11
77#define	CPLD_REG_FAN2_TACHO_U	0x12
78#define	CPLD_REG_FAN2_TACHO_L	0x13
79#define	CPLD_REG_FAN3_TACHO_U	0x14
80#define	CPLD_REG_FAN3_TACHO_L	0x15
81#define	CPLD_REG_DATE_UU	0x20
82#define	CPLD_REG_DATE_UL	0x21
83#define	CPLD_REG_DATE_LU	0x22
84#define	CPLD_REG_DATE_LL	0x23
85#define	CPLD_REG_TIME_UU	0x24
86#define	CPLD_REG_TIME_UL	0x25
87#define	CPLD_REG_TIME_LU	0x26
88#define	CPLD_REG_TIME_LL	0x27
89#define	CPLD_REG_SCR1		0x5c
90#define	CPLD_REG_SCR2		0x6a
91#define	CPLD_REG_RAM		0x80
92
93struct cpld_softc {
94	device_t	 sc_dev;
95	struct resource	*sc_mem;
96	struct cdev	*sc_cdev;
97	struct mtx	 sc_mutex;
98	bool		 sc_isopen;
99};
100
101static d_open_t		cpld_open;
102static d_close_t	cpld_close;
103static d_ioctl_t	cpld_ioctl;
104
105static struct cdevsw cpld_cdevsw = {
106	.d_version =	D_VERSION,
107	.d_open =	cpld_open,
108	.d_close =	cpld_close,
109	.d_ioctl =	cpld_ioctl,
110	.d_name =	"nvram",
111};
112
113static device_probe_t	cpld_probe;
114static device_attach_t	cpld_attach;
115static int		cpld_fan_sysctl(SYSCTL_HANDLER_ARGS);
116
117static device_method_t cpld_methods[] = {
118	DEVMETHOD(device_probe,		cpld_probe),
119	DEVMETHOD(device_attach,	cpld_attach),
120
121	DEVMETHOD_END
122};
123
124static driver_t cpld_driver = {
125	"cpld",
126	cpld_methods,
127	sizeof(struct cpld_softc)
128};
129
130static devclass_t cpld_devclass;
131DRIVER_MODULE(cpld, lbc, cpld_driver, cpld_devclass, 0, 0);
132
133static void
134cpld_write(struct cpld_softc *sc, int addr, int data)
135{
136	if (addr >= CPLD_REG_RAM) {
137		bus_write_1(sc->sc_mem, CPLD_MEM_ADDR_H, addr);
138		bus_write_1(sc->sc_mem, CPLD_MEM_ADDR_L, addr);
139	} else
140		bus_write_1(sc->sc_mem, CPLD_MEM_ADDR_H, addr);
141	bus_write_1(sc->sc_mem, CPLD_MEM_DATA, data);
142}
143
144static int
145cpld_read(struct cpld_softc *sc, int addr)
146{
147	if (addr >= CPLD_REG_RAM) {
148		bus_write_1(sc->sc_mem, CPLD_MEM_ADDR_H, addr);
149		bus_write_1(sc->sc_mem, CPLD_MEM_ADDR_L, addr);
150	} else
151		bus_write_1(sc->sc_mem, CPLD_MEM_ADDR_H, addr);
152
153	return (bus_read_1(sc->sc_mem, CPLD_MEM_DATA));
154}
155
156/*
157 * This is only to read a register that's split into two 8-bit registers.
158 * Dual-port RAM is not accepted for this purpose.
159 */
160static int
161cpld_read_pair(struct cpld_softc *sc, int addr)
162{
163	int tmp;
164
165	KASSERT(addr <= 0xff, ("Invalid register-pair base address %x.", addr));
166	bus_write_1(sc->sc_mem, CPLD_MEM_ADDR_H, addr);
167	tmp = bus_read_1(sc->sc_mem, CPLD_MEM_DATA) << 8;
168
169	bus_write_1(sc->sc_mem, CPLD_MEM_ADDR_H, addr + 1);
170	tmp |= bus_read_1(sc->sc_mem, CPLD_MEM_DATA);
171
172	return (tmp);
173}
174
175static int
176cpld_probe(device_t dev)
177{
178	if (!ofw_bus_is_compatible(dev, "aeon,tabor-cpld"))
179		return (ENXIO);
180
181	device_set_desc(dev, "AmigaOne Tabor CPLD");
182
183	return (BUS_PROBE_GENERIC);
184}
185
186static int
187cpld_attach(device_t dev)
188{
189	struct make_dev_args mda;
190	struct cpld_softc *sc;
191	int rid;
192	int date, time, tmp;
193	int err;
194	struct sysctl_ctx_list *ctx;
195	struct sysctl_oid *tree;
196
197	sc = device_get_softc(dev);
198	sc->sc_dev = dev;
199
200	rid = 0;
201	sc->sc_mem = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
202	    RF_ACTIVE|RF_SHAREABLE);
203	if (sc->sc_mem == NULL) {
204		device_printf(dev, "Unable to allocate memory resource.\n");
205		return (ENXIO);
206	}
207	mtx_init(&sc->sc_mutex, "cpld", NULL, MTX_DEF);
208
209	if (bootverbose) {
210		date = (cpld_read_pair(sc, CPLD_REG_DATE_UU) << 16) |
211		    cpld_read_pair(sc, CPLD_REG_DATE_LU);
212		time = (cpld_read_pair(sc, CPLD_REG_TIME_UU) << 16) |
213		    cpld_read_pair(sc, CPLD_REG_TIME_LU);
214
215		device_printf(dev, "Build date: %04x-%02x-%02x\n",
216		    (date >> 16) & 0xffff, (date >> 8) & 0xff, date & 0xff);
217#if 0
218		/* Build time is nonsense on tested system. */
219		device_printf(dev, "Build time: %02x:%02x:%02x\n",
220		    (time >> 16) & 0xff, (time >> 8) & 0xff, time & 0xff);
221#endif
222	}
223
224	tmp = cpld_read(sc, CPLD_REG_HWREV);
225	device_printf(dev, "Hardware revision: %d\n", tmp);
226
227	ctx = device_get_sysctl_ctx(dev);
228	tree = device_get_sysctl_tree(dev);
229
230	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
231	    "cpu_fan", CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, sc,
232	    CPLD_REG_FAN1_TACHO_U, cpld_fan_sysctl, "I",
233	    "CPU Fan speed in RPM");
234
235	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
236	    "case_1_fan", CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, sc,
237	    CPLD_REG_FAN2_TACHO_U, cpld_fan_sysctl, "I",
238	    "Case fan 1 speed in RPM");
239
240	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
241	    "case_2_fan", CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, sc,
242	    CPLD_REG_FAN3_TACHO_U, cpld_fan_sysctl, "I",
243	    "Case fan 2 speed in RPM");
244
245	make_dev_args_init(&mda);
246	mda.mda_flags =  MAKEDEV_CHECKNAME;
247	mda.mda_devsw = &cpld_cdevsw;
248	mda.mda_uid = UID_ROOT;
249	mda.mda_gid = GID_WHEEL;
250	mda.mda_mode = 0660;
251	err = make_dev_s(&mda, &sc->sc_cdev, "cpld");
252	if (err != 0) {
253		device_printf(dev, "Error creating character device: %d\n", err);
254		device_printf(dev, "Only sysctl interfaces will be available.\n");
255	}
256
257	return (0);
258}
259
260static int
261cpld_fan_sysctl(SYSCTL_HANDLER_ARGS)
262{
263	struct cpld_softc *sc;
264	int error, old, rpm;
265	int fan_reg;
266
267	sc = arg1;
268	fan_reg = arg2;
269	mtx_lock(&sc->sc_mutex);
270	/* Read until we get some level of read stability. */
271	rpm = cpld_read(sc, fan_reg);
272	do {
273		old = rpm;
274		rpm = cpld_read_pair(sc, fan_reg);
275	} while (abs(rpm - old) > 10);
276	mtx_unlock(&sc->sc_mutex);
277
278	/* Convert RPS->RPM. */
279	rpm *= 60;
280	error = sysctl_handle_int(oidp, &rpm, 0, req);
281
282	return (error);
283}
284
285static int
286cpld_open(struct cdev *dev, int flags, int fmt, struct thread *td)
287{
288	struct cpld_softc *sc = dev->si_drv1;
289
290	if (sc->sc_isopen)
291		return (EBUSY);
292	sc->sc_isopen = 1;
293	return (0);
294}
295
296static int
297cpld_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
298{
299	struct cpld_softc *sc = dev->si_drv1;
300
301	sc->sc_isopen = 0;
302	return (0);
303}
304
305/*
306 * Send a command over the CPLD to the other side.
307 *
308 * This will first copy the data into the dual-port RAM, then signal the other
309 * side by writing to the mailbox.
310 */
311static int
312cpld_send(device_t dev, struct cpld_cmd_data *d)
313{
314	struct cpld_softc *sc;
315	uint16_t *word;
316	int i;
317
318	if (d->cmd > USHRT_MAX)
319		return (EINVAL);
320
321	sc = device_get_softc(dev);
322
323	mtx_lock(&sc->sc_mutex);
324	for (i = 0, word = d->words; i < d->len; i++, word++) {
325		if (i == 0)
326			cpld_write(sc, CPLD_REG_RAM + d->offset, *word);
327		else
328			bus_write_4(sc->sc_mem, CPLD_MEM_DATA, *word);
329	}
330
331	cpld_write(sc, CPLD_REG_MBC2X, d->cmd);
332	mtx_unlock(&sc->sc_mutex);
333
334	return (0);
335}
336
337static int
338cpld_recv(device_t dev, struct cpld_cmd_data *d)
339{
340	struct cpld_softc *sc;
341	uint16_t *word;
342	int i;
343
344	sc = device_get_softc(dev);
345
346	mtx_lock(&sc->sc_mutex);
347	d->cmd = cpld_read(sc, CPLD_REG_MBX2C);
348
349	for (i = 0, word = d->words; i < d->len; i++, word++) {
350		if (i == 0)
351			*word = cpld_read(sc, CPLD_REG_RAM + d->offset);
352		else
353			*word = bus_read_4(sc->sc_mem, CPLD_MEM_DATA);
354	}
355	mtx_unlock(&sc->sc_mutex);
356
357	return (0);
358}
359
360static int
361cpld_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag,
362    struct thread *td)
363{
364	struct cpld_softc *sc;
365	struct cpld_cmd_data *d;
366	void *xfer_data, *tmp;
367	int err;
368
369	sc = dev->si_drv1;
370
371	err = 0;
372	d = (struct cpld_cmd_data *)data;
373	if (d->len + d->offset > CPLD_MAX_DRAM_WORDS) {
374		return (EINVAL);
375	}
376	xfer_data = malloc(d->len * sizeof(uint16_t), M_TEMP, M_WAITOK);
377
378	switch (cmd) {
379	case IOCCPLDSEND:
380		err = copyin(d->words, xfer_data, d->len * sizeof(uint16_t));
381		d->words = xfer_data;
382		if (err == 0)
383			err = cpld_send(sc->sc_dev, d);
384		break;
385	case IOCCPLDRECV:
386		tmp = d->words;
387		d->words = xfer_data;
388		err = cpld_recv(sc->sc_dev, d);
389		d->words = tmp;
390		if (err == 0)
391			err = copyout(xfer_data, d->words,
392			    d->len * sizeof(uint16_t));
393		break;
394	default:
395		err = ENOTTY;
396		break;
397	}
398	free(xfer_data, M_TEMP);
399
400	return (err);
401}
402