xref: /openbsd/sys/dev/pci/amdiic.c (revision 9e6efb0a)
1 /*	$OpenBSD: amdiic.c,v 1.14 2024/05/24 06:02:53 jsg Exp $	*/
2 
3 /*
4  * Copyright (c) 2005 Alexander Yurchenko <grange@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 /*
20  * AMD-8111 SMBus controller driver.
21  */
22 
23 #include <sys/param.h>
24 #include <sys/systm.h>
25 #include <sys/device.h>
26 #include <sys/rwlock.h>
27 
28 #include <machine/bus.h>
29 
30 #include <dev/pci/pcidevs.h>
31 #include <dev/pci/pcireg.h>
32 #include <dev/pci/pcivar.h>
33 
34 #include <dev/i2c/i2cvar.h>
35 
36 #ifdef AMDIIC_DEBUG
37 #define DPRINTF(x) printf x
38 #else
39 #define DPRINTF(x)
40 #endif
41 
42 #define AMDIIC_DELAY	100
43 #define AMDIIC_TIMEOUT	1
44 
45 /* PCI configuration registers */
46 #define AMD8111_SMB_BASE	0x10	/* SMBus base address */
47 #define AMD8111_SMB_MISC	0x48	/* miscellaneous control */
48 #define AMD8111_SMB_MISC_SU	(1 << 0)	/* 16x clock speed-up */
49 #define AMD8111_SMB_MISC_INTEN	(1 << 1)	/* PCI IRQ enabled */
50 #define AMD8111_SMB_MISC_SCIEN	(1 << 2)	/* SCI enabled */
51 
52 /* SMBus I/O registers */
53 #define AMD8111_SMB_SC_DATA	0x00	/* data port */
54 #define AMD8111_SMB_SC_ST	0x04	/* status */
55 #define AMD8111_SMB_SC_ST_OBF	(1 << 0)	/* output buffer full */
56 #define AMD8111_SMB_SC_ST_IBF	(1 << 1)	/* input buffer full */
57 #define AMD8111_SMB_SC_ST_CMD	(1 << 3)	/* command byte */
58 #define AMD8111_SMB_SC_ST_BITS	"\020\001OBF\002IBF\004CMD"
59 #define AMD8111_SMB_SC_CMD	0x04	/* command port */
60 #define AMD8111_SMB_SC_CMD_RD	0x80		/* read */
61 #define AMD8111_SMB_SC_CMD_WR	0x81		/* write */
62 #define AMD8111_SMB_SC_IC	0x08	/* interrupt control */
63 
64 /* Host controller interface registers */
65 #define AMD8111_SMB_PROTO	0x00	/* protocol */
66 #define AMD8111_SMB_PROTO_READ	0x01		/* read direction */
67 #define AMD8111_SMB_PROTO_QUICK	0x02		/* QUICK command */
68 #define AMD8111_SMB_PROTO_BYTE	0x04		/* BYTE command */
69 #define AMD8111_SMB_PROTO_BDATA	0x06		/* BYTE DATA command */
70 #define AMD8111_SMB_PROTO_WDATA	0x08		/* WORD DATA command */
71 #define AMD8111_SMB_STAT	0x01	/* status */
72 #define AMD8111_SMB_STAT_MASK	0x1f
73 #define AMD8111_SMB_STAT_DONE	(1 << 7)	/* command completion */
74 #define AMD8111_SMB_ADDR	0x02	/* address */
75 #define AMD8111_SMB_ADDR_SHIFT	1
76 #define AMD8111_SMB_CMD		0x03	/* SMBus command */
77 #define AMD8111_SMB_DATA(x)	(0x04 + (x)) /* SMBus data */
78 
79 struct amdiic_softc {
80 	struct device		sc_dev;
81 
82 	bus_space_tag_t		sc_iot;
83 	bus_space_handle_t	sc_ioh;
84 	void *			sc_ih;
85 	int			sc_poll;
86 
87 	struct i2c_controller	sc_i2c_tag;
88 	struct rwlock		sc_i2c_lock;
89 	struct {
90 		i2c_op_t     op;
91 		void *       buf;
92 		size_t       len;
93 		int          flags;
94 		volatile int error;
95 	}			sc_i2c_xfer;
96 };
97 
98 int	amdiic_match(struct device *, void *, void *);
99 void	amdiic_attach(struct device *, struct device *, void *);
100 
101 int	amdiic_read(struct amdiic_softc *, u_int8_t);
102 int	amdiic_write(struct amdiic_softc *, u_int8_t, u_int8_t);
103 int	amdiic_wait(struct amdiic_softc *, int);
104 
105 int	amdiic_i2c_acquire_bus(void *, int);
106 void	amdiic_i2c_release_bus(void *, int);
107 int	amdiic_i2c_exec(void *, i2c_op_t, i2c_addr_t, const void *, size_t,
108 	    void *, size_t, int);
109 
110 int	amdiic_intr(void *);
111 
112 const struct cfattach amdiic_ca = {
113 	sizeof(struct amdiic_softc),
114 	amdiic_match,
115 	amdiic_attach
116 };
117 
118 struct cfdriver amdiic_cd = {
119 	NULL, "amdiic", DV_DULL
120 };
121 
122 const struct pci_matchid amdiic_ids[] = {
123 	{ PCI_VENDOR_AMD, PCI_PRODUCT_AMD_8111_SMB }
124 };
125 
126 int
127 amdiic_match(struct device *parent, void *match, void *aux)
128 {
129 	return (pci_matchbyid(aux, amdiic_ids,
130 	    sizeof(amdiic_ids) / sizeof(amdiic_ids[0])));
131 }
132 
133 void
134 amdiic_attach(struct device *parent, struct device *self, void *aux)
135 {
136 	struct amdiic_softc *sc = (struct amdiic_softc *)self;
137 	struct pci_attach_args *pa = aux;
138 	struct i2cbus_attach_args iba;
139 	pcireg_t conf;
140 	bus_size_t iosize;
141 	pci_intr_handle_t ih;
142 	const char *intrstr = NULL;
143 
144 	/* Map I/O space */
145 	if (pci_mapreg_map(pa, AMD8111_SMB_BASE, PCI_MAPREG_TYPE_IO, 0,
146 	    &sc->sc_iot, &sc->sc_ioh, NULL, &iosize, 0)) {
147 		printf(": can't map i/o space\n");
148 		return;
149 	}
150 
151 	/* Read configuration */
152 	conf = pci_conf_read(pa->pa_pc, pa->pa_tag, AMD8111_SMB_MISC);
153 	DPRINTF((": conf 0x%08x", conf));
154 
155 	sc->sc_poll = 1;
156 	if (conf & AMD8111_SMB_MISC_SCIEN) {
157 		/* No PCI IRQ */
158 		printf(": SCI");
159 	} else if (conf & AMD8111_SMB_MISC_INTEN) {
160 		/* Install interrupt handler */
161 		if (pci_intr_map(pa, &ih) == 0) {
162 			intrstr = pci_intr_string(pa->pa_pc, ih);
163 			sc->sc_ih = pci_intr_establish(pa->pa_pc, ih, IPL_BIO,
164 			    amdiic_intr, sc, sc->sc_dev.dv_xname);
165 			if (sc->sc_ih != NULL) {
166 				printf(": %s", intrstr);
167 				sc->sc_poll = 0;
168 			}
169 		}
170 		if (sc->sc_poll)
171 			printf(": polling");
172 	}
173 
174 	printf("\n");
175 
176 	/* Attach I2C bus */
177 	rw_init(&sc->sc_i2c_lock, "iiclk");
178 	sc->sc_i2c_tag.ic_cookie = sc;
179 	sc->sc_i2c_tag.ic_acquire_bus = amdiic_i2c_acquire_bus;
180 	sc->sc_i2c_tag.ic_release_bus = amdiic_i2c_release_bus;
181 	sc->sc_i2c_tag.ic_exec = amdiic_i2c_exec;
182 
183 	bzero(&iba, sizeof(iba));
184 	iba.iba_name = "iic";
185 	iba.iba_tag = &sc->sc_i2c_tag;
186 	config_found(self, &iba, iicbus_print);
187 
188 	return;
189 }
190 
191 int
192 amdiic_read(struct amdiic_softc *sc, u_int8_t reg)
193 {
194 	if (amdiic_wait(sc, 0))
195 		return (-1);
196 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, AMD8111_SMB_SC_CMD,
197 	    AMD8111_SMB_SC_CMD_RD);
198 	if (amdiic_wait(sc, 0))
199 		return (-1);
200 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, AMD8111_SMB_SC_DATA, reg);
201 	if (amdiic_wait(sc, 1))
202 		return (-1);
203 
204 	return (bus_space_read_1(sc->sc_iot, sc->sc_ioh, AMD8111_SMB_SC_DATA));
205 }
206 
207 int
208 amdiic_write(struct amdiic_softc *sc, u_int8_t reg, u_int8_t val)
209 {
210 	if (amdiic_wait(sc, 0))
211 		return (-1);
212 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, AMD8111_SMB_SC_CMD,
213 	    AMD8111_SMB_SC_CMD_WR);
214 	if (amdiic_wait(sc, 0))
215 		return (-1);
216 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, AMD8111_SMB_SC_DATA, reg);
217 	if (amdiic_wait(sc, 0))
218 		return (-1);
219 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, AMD8111_SMB_SC_DATA, val);
220 
221 	return (0);
222 }
223 
224 int
225 amdiic_wait(struct amdiic_softc *sc, int output)
226 {
227 	int retries;
228 	u_int8_t st;
229 
230 	for (retries = 100; retries > 0; retries--) {
231 		st = bus_space_read_1(sc->sc_iot, sc->sc_ioh,
232 		    AMD8111_SMB_SC_ST);
233 		if (output && (st & AMD8111_SMB_SC_ST_OBF))
234 			return (0);
235 		if (!output && (st & AMD8111_SMB_SC_ST_IBF) == 0)
236 			return (0);
237 		DELAY(1);
238 	}
239 	DPRINTF(("%s: %s wait timeout: st 0x%b\n", sc->sc_dev.dv_xname,
240 	    (output ? "output" : "input"), st));
241 
242 	return (1);
243 }
244 
245 int
246 amdiic_i2c_acquire_bus(void *cookie, int flags)
247 {
248 	struct amdiic_softc *sc = cookie;
249 
250 	if (cold || sc->sc_poll || (flags & I2C_F_POLL))
251 		return (0);
252 
253 	return (rw_enter(&sc->sc_i2c_lock, RW_WRITE | RW_INTR));
254 }
255 
256 void
257 amdiic_i2c_release_bus(void *cookie, int flags)
258 {
259 	struct amdiic_softc *sc = cookie;
260 
261 	if (cold || sc->sc_poll || (flags & I2C_F_POLL))
262 		return;
263 
264 	rw_exit(&sc->sc_i2c_lock);
265 }
266 
267 int
268 amdiic_i2c_exec(void *cookie, i2c_op_t op, i2c_addr_t addr,
269     const void *cmdbuf, size_t cmdlen, void *buf, size_t len, int flags)
270 {
271 	struct amdiic_softc *sc = cookie;
272 	u_int8_t *b;
273 	u_int8_t proto, st;
274 	int retries;
275 
276 	DPRINTF(("%s: exec: op %d, addr 0x%02x, cmdlen %d, len %d, "
277 	    "flags 0x%02x\n", sc->sc_dev.dv_xname, op, addr,
278 	    cmdlen, len, flags));
279 
280 	if (cold || sc->sc_poll)
281 		flags |= I2C_F_POLL;
282 
283 	if (!I2C_OP_STOP_P(op) || cmdlen > 1 || len > 2)
284 		return (1);
285 
286 	/* Setup transfer */
287 	sc->sc_i2c_xfer.op = op;
288 	sc->sc_i2c_xfer.buf = buf;
289 	sc->sc_i2c_xfer.len = len;
290 	sc->sc_i2c_xfer.flags = flags;
291 	sc->sc_i2c_xfer.error = 0;
292 
293 	/* Set slave address */
294 	if (amdiic_write(sc, AMD8111_SMB_ADDR,
295 	    addr << AMD8111_SMB_ADDR_SHIFT) == -1)
296 		return (1);
297 
298 	b = (void *)cmdbuf;
299 	if (cmdlen > 0)
300 		/* Set command byte */
301 		if (amdiic_write(sc, AMD8111_SMB_CMD, b[0]) == -1)
302 			return (1);
303 
304 	if (I2C_OP_WRITE_P(op)) {
305 		/* Write data */
306 		b = buf;
307 		if (len > 0)
308 			if (amdiic_write(sc, AMD8111_SMB_DATA(0), b[0]) == -1)
309 				return (1);
310 		if (len > 1)
311 			if (amdiic_write(sc, AMD8111_SMB_DATA(1), b[1]) == -1)
312 				return (1);
313 	}
314 
315 	/* Set SMBus command */
316 	if (len == 0)
317 		proto = AMD8111_SMB_PROTO_BYTE;
318 	else if (len == 1)
319 		proto = AMD8111_SMB_PROTO_BDATA;
320 	else if (len == 2)
321 		proto = AMD8111_SMB_PROTO_WDATA;
322 	else
323 		panic("%s: unexpected len %zd", __func__, len);
324 
325 	/* Set direction */
326 	if (I2C_OP_READ_P(op))
327 		proto |= AMD8111_SMB_PROTO_READ;
328 
329 	/* Start transaction */
330 	amdiic_write(sc, AMD8111_SMB_PROTO, proto);
331 
332 	if (flags & I2C_F_POLL) {
333 		/* Poll for completion */
334 		DELAY(AMDIIC_DELAY);
335 		for (retries = 1000; retries > 0; retries--) {
336 			st = amdiic_read(sc, AMD8111_SMB_STAT);
337 			if (st != 0)
338 				break;
339 			DELAY(AMDIIC_DELAY);
340 		}
341 		if (st == 0) {
342 			printf("%s: exec: op %d, addr 0x%02x, cmdlen %zu, "
343 			    "len %zu, flags 0x%02x: timeout\n",
344 			    sc->sc_dev.dv_xname, op, addr, cmdlen, len, flags);
345 			return (1);
346 		}
347 		amdiic_intr(sc);
348 	} else {
349 		/* Wait for interrupt */
350 		if (tsleep_nsec(sc, PRIBIO, "amdiic",
351 		    SEC_TO_NSEC(AMDIIC_TIMEOUT)))
352 			return (1);
353 	}
354 
355 	if (sc->sc_i2c_xfer.error)
356 		return (1);
357 
358 	return (0);
359 }
360 
361 int
362 amdiic_intr(void *arg)
363 {
364 	struct amdiic_softc *sc = arg;
365 	int st;
366 	u_int8_t *b;
367 	size_t len;
368 
369 	/* Read status */
370 	if ((st = amdiic_read(sc, AMD8111_SMB_STAT)) == -1)
371 		return (-1);
372 	if (st == 0)
373 		/* Interrupt was not for us */
374 		return (0);
375 
376 	DPRINTF(("%s: intr: st 0x%02x\n", sc->sc_dev.dv_xname, st));
377 
378 	/* Check for errors */
379 	if ((st & AMD8111_SMB_STAT_MASK) != 0) {
380 		sc->sc_i2c_xfer.error = 1;
381 		goto done;
382 	}
383 
384 	if (st & AMD8111_SMB_STAT_DONE) {
385 		if (I2C_OP_WRITE_P(sc->sc_i2c_xfer.op))
386 			goto done;
387 
388 		/* Read data */
389 		b = sc->sc_i2c_xfer.buf;
390 		len = sc->sc_i2c_xfer.len;
391 		if (len > 0)
392 			b[0] = amdiic_read(sc, AMD8111_SMB_DATA(0));
393 		if (len > 1)
394 			b[1] = amdiic_read(sc, AMD8111_SMB_DATA(1));
395 	}
396 
397 done:
398 	if ((sc->sc_i2c_xfer.flags & I2C_F_POLL) == 0)
399 		wakeup(sc);
400 	return (1);
401 }
402