1/*-
2 * Copyright (c) 2011 Henrik Brix Andersen <brix@FreeBSD.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
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 * AMD Geode LX CS5536 System Management Bus controller.
30 *
31 * Although AMD refers to this device as an SMBus controller, it
32 * really is an I2C controller (It lacks SMBus ALERT# and Alert
33 * Response support).
34 *
35 * The driver is implemented as an interrupt-driven state machine,
36 * supporting both master and slave mode.
37 */
38#include <sys/param.h>
39#include <sys/systm.h>
40#include <sys/bus.h>
41#include <sys/kernel.h>
42#include <sys/module.h>
43#include <sys/lock.h>
44#include <sys/mutex.h>
45#include <sys/sysctl.h>
46#ifdef GLXIIC_DEBUG
47#include <sys/syslog.h>
48#endif
49
50#include <dev/pci/pcireg.h>
51#include <dev/pci/pcivar.h>
52
53#include <machine/bus.h>
54#include <sys/rman.h>
55#include <machine/resource.h>
56
57#include <dev/iicbus/iiconf.h>
58#include <dev/iicbus/iicbus.h>
59
60#include "iicbus_if.h"
61
62/* CS5536 PCI-ISA ID. */
63#define	GLXIIC_CS5536_DEV_ID		0x20901022
64
65/* MSRs. */
66#define	GLXIIC_MSR_PIC_YSEL_HIGH	0x51400021
67
68/* Bus speeds. */
69#define	GLXIIC_SLOW	0x0258	/*  10 kHz. */
70#define	GLXIIC_FAST	0x0078	/*  50 kHz. */
71#define	GLXIIC_FASTEST	0x003c	/* 100 kHz. */
72
73/* Default bus activity timeout in milliseconds. */
74#define GLXIIC_DEFAULT_TIMEOUT	35
75
76/* GPIO register offsets. */
77#define	GLXIIC_GPIOL_OUT_AUX1_SEL	0x10
78#define	GLXIIC_GPIOL_IN_AUX1_SEL	0x34
79
80/* GPIO 14 (SMB_CLK) and 15 (SMB_DATA) bitmasks. */
81#define	GLXIIC_GPIO_14_15_ENABLE	0x0000c000
82#define	GLXIIC_GPIO_14_15_DISABLE	0xc0000000
83
84/* SMB register offsets. */
85#define	GLXIIC_SMB_SDA				0x00
86#define	GLXIIC_SMB_STS				0x01
87#define		GLXIIC_SMB_STS_SLVSTP_BIT	(1 << 7)
88#define		GLXIIC_SMB_STS_SDAST_BIT	(1 << 6)
89#define		GLXIIC_SMB_STS_BER_BIT		(1 << 5)
90#define		GLXIIC_SMB_STS_NEGACK_BIT	(1 << 4)
91#define		GLXIIC_SMB_STS_STASTR_BIT	(1 << 3)
92#define		GLXIIC_SMB_STS_NMATCH_BIT	(1 << 2)
93#define		GLXIIC_SMB_STS_MASTER_BIT	(1 << 1)
94#define		GLXIIC_SMB_STS_XMIT_BIT		(1 << 0)
95#define	GLXIIC_SMB_CTRL_STS			0x02
96#define		GLXIIC_SMB_CTRL_STS_TGSCL_BIT	(1 << 5)
97#define		GLXIIC_SMB_CTRL_STS_TSDA_BIT	(1 << 4)
98#define		GLXIIC_SMB_CTRL_STS_GCMTCH_BIT	(1 << 3)
99#define		GLXIIC_SMB_CTRL_STS_MATCH_BIT	(1 << 2)
100#define		GLXIIC_SMB_CTRL_STS_BB_BIT	(1 << 1)
101#define		GLXIIC_SMB_CTRL_STS_BUSY_BIT	(1 << 0)
102#define	GLXIIC_SMB_CTRL1			0x03
103#define		GLXIIC_SMB_CTRL1_STASTRE_BIT	(1 << 7)
104#define		GLXIIC_SMB_CTRL1_NMINTE_BIT	(1 << 6)
105#define		GLXIIC_SMB_CTRL1_GCMEN_BIT	(1 << 5)
106#define		GLXIIC_SMB_CTRL1_ACK_BIT	(1 << 4)
107#define		GLXIIC_SMB_CTRL1_INTEN_BIT	(1 << 2)
108#define		GLXIIC_SMB_CTRL1_STOP_BIT	(1 << 1)
109#define		GLXIIC_SMB_CTRL1_START_BIT	(1 << 0)
110#define	GLXIIC_SMB_ADDR				0x04
111#define		GLXIIC_SMB_ADDR_SAEN_BIT	(1 << 7)
112#define	GLXIIC_SMB_CTRL2			0x05
113#define		GLXIIC_SMB_CTRL2_EN_BIT		(1 << 0)
114#define	GLXIIC_SMB_CTRL3			0x06
115
116typedef enum {
117	GLXIIC_STATE_IDLE,
118	GLXIIC_STATE_SLAVE_TX,
119	GLXIIC_STATE_SLAVE_RX,
120	GLXIIC_STATE_MASTER_ADDR,
121	GLXIIC_STATE_MASTER_TX,
122	GLXIIC_STATE_MASTER_RX,
123	GLXIIC_STATE_MASTER_STOP,
124	GLXIIC_STATE_MAX,
125} glxiic_state_t;
126
127struct glxiic_softc {
128	device_t	 dev;		/* Myself. */
129	device_t	 iicbus;	/* IIC bus. */
130	struct mtx	 mtx;		/* Lock. */
131	glxiic_state_t	 state;		/* Driver state. */
132	struct callout	 callout;	/* Driver state timeout callout. */
133	int		 timeout;	/* Driver state timeout (ms). */
134
135	int		 smb_rid;	/* SMB controller resource ID. */
136	struct resource *smb_res;	/* SMB controller resource. */
137	int		 gpio_rid;	/* GPIO resource ID. */
138	struct resource *gpio_res;	/* GPIO resource. */
139
140	int		 irq_rid;	/* IRQ resource ID. */
141	struct resource *irq_res;	/* IRQ resource. */
142	void		*irq_handler;	/* IRQ handler cookie. */
143	int		 old_irq;	/* IRQ mapped by board firmware. */
144
145	struct iic_msg	*msg;		/* Current master mode message. */
146	uint32_t	 nmsgs;		/* Number of messages remaining. */
147	uint8_t		*data;		/* Current master mode data byte. */
148	uint16_t	 ndata;		/* Number of data bytes remaining. */
149	int		 error;		/* Last master mode error. */
150
151	uint8_t		 addr;		/* Own address. */
152	uint16_t	 sclfrq;	/* Bus frequency. */
153};
154
155#ifdef GLXIIC_DEBUG
156#define GLXIIC_DEBUG_LOG(fmt, args...)	\
157	log(LOG_DEBUG, "%s: " fmt "\n" , __func__ , ## args)
158#else
159#define GLXIIC_DEBUG_LOG(fmt, args...)
160#endif
161
162#define	GLXIIC_SCLFRQ(n)		((n << 1))
163#define	GLXIIC_SMBADDR(n)		((n >> 1))
164#define	GLXIIC_SMB_IRQ_TO_MAP(n)	((n << 16))
165#define	GLXIIC_MAP_TO_SMB_IRQ(n)	((n >> 16) & 0xf)
166
167#define	GLXIIC_LOCK(_sc)		mtx_lock(&_sc->mtx)
168#define	GLXIIC_UNLOCK(_sc)		mtx_unlock(&_sc->mtx)
169#define	GLXIIC_LOCK_INIT(_sc)		\
170	mtx_init(&_sc->mtx, device_get_nameunit(_sc->dev), "glxiic", MTX_DEF)
171#define	GLXIIC_SLEEP(_sc)		\
172	mtx_sleep(_sc, &_sc->mtx, IICPRI, "glxiic", 0)
173#define	GLXIIC_WAKEUP(_sc)		wakeup(_sc);
174#define	GLXIIC_LOCK_DESTROY(_sc)	mtx_destroy(&_sc->mtx);
175#define	GLXIIC_ASSERT_LOCKED(_sc)	mtx_assert(&_sc->mtx, MA_OWNED);
176
177typedef	int (glxiic_state_callback_t)(struct glxiic_softc *sc,
178    uint8_t status);
179
180static glxiic_state_callback_t	glxiic_state_idle_callback;
181static glxiic_state_callback_t	glxiic_state_slave_tx_callback;
182static glxiic_state_callback_t	glxiic_state_slave_rx_callback;
183static glxiic_state_callback_t	glxiic_state_master_addr_callback;
184static glxiic_state_callback_t	glxiic_state_master_tx_callback;
185static glxiic_state_callback_t	glxiic_state_master_rx_callback;
186static glxiic_state_callback_t	glxiic_state_master_stop_callback;
187
188struct glxiic_state_table_entry {
189	glxiic_state_callback_t *callback;
190	boolean_t master;
191};
192typedef struct glxiic_state_table_entry glxiic_state_table_entry_t;
193
194static glxiic_state_table_entry_t glxiic_state_table[GLXIIC_STATE_MAX] = {
195	[GLXIIC_STATE_IDLE] = {
196		.callback = &glxiic_state_idle_callback,
197		.master = FALSE,
198	},
199
200	[GLXIIC_STATE_SLAVE_TX] = {
201		.callback = &glxiic_state_slave_tx_callback,
202		.master = FALSE,
203	},
204
205	[GLXIIC_STATE_SLAVE_RX] = {
206		.callback = &glxiic_state_slave_rx_callback,
207		.master = FALSE,
208	},
209
210	[GLXIIC_STATE_MASTER_ADDR] = {
211		.callback = &glxiic_state_master_addr_callback,
212		.master = TRUE,
213	},
214
215	[GLXIIC_STATE_MASTER_TX] = {
216		.callback = &glxiic_state_master_tx_callback,
217		.master = TRUE,
218	},
219
220	[GLXIIC_STATE_MASTER_RX] = {
221		.callback = &glxiic_state_master_rx_callback,
222		.master = TRUE,
223	},
224
225	[GLXIIC_STATE_MASTER_STOP] = {
226		.callback = &glxiic_state_master_stop_callback,
227		.master = TRUE,
228	},
229};
230
231static void	glxiic_identify(driver_t *driver, device_t parent);
232static int	glxiic_probe(device_t dev);
233static int	glxiic_attach(device_t dev);
234static int	glxiic_detach(device_t dev);
235
236static uint8_t	glxiic_read_status_locked(struct glxiic_softc *sc);
237static void	glxiic_stop_locked(struct glxiic_softc *sc);
238static void	glxiic_timeout(void *arg);
239static void	glxiic_start_timeout_locked(struct glxiic_softc *sc);
240static void	glxiic_set_state_locked(struct glxiic_softc *sc,
241    glxiic_state_t state);
242static int	glxiic_handle_slave_match_locked(struct glxiic_softc *sc,
243    uint8_t status);
244static void	glxiic_intr(void *arg);
245
246static int	glxiic_reset(device_t dev, u_char speed, u_char addr,
247    u_char *oldaddr);
248static int	glxiic_transfer(device_t dev, struct iic_msg *msgs,
249    uint32_t nmsgs);
250
251static void	glxiic_smb_map_interrupt(int irq);
252static void 	glxiic_gpio_enable(struct glxiic_softc *sc);
253static void 	glxiic_gpio_disable(struct glxiic_softc *sc);
254static void	glxiic_smb_enable(struct glxiic_softc *sc, uint8_t speed,
255    uint8_t addr);
256static void	glxiic_smb_disable(struct glxiic_softc *sc);
257
258static device_method_t glxiic_methods[] = {
259	DEVMETHOD(device_identify,	glxiic_identify),
260	DEVMETHOD(device_probe,		glxiic_probe),
261	DEVMETHOD(device_attach,	glxiic_attach),
262	DEVMETHOD(device_detach,	glxiic_detach),
263
264	DEVMETHOD(iicbus_reset,		glxiic_reset),
265	DEVMETHOD(iicbus_transfer,	glxiic_transfer),
266	DEVMETHOD(iicbus_callback,	iicbus_null_callback),
267
268	{ 0, 0 }
269};
270
271static driver_t glxiic_driver = {
272	"glxiic",
273	glxiic_methods,
274	sizeof(struct glxiic_softc),
275};
276
277static devclass_t glxiic_devclass;
278
279DRIVER_MODULE(glxiic, isab, glxiic_driver, glxiic_devclass, 0, 0);
280DRIVER_MODULE(iicbus, glxiic, iicbus_driver, iicbus_devclass, 0, 0);
281MODULE_DEPEND(glxiic, iicbus, 1, 1, 1);
282
283static void
284glxiic_identify(driver_t *driver, device_t parent)
285{
286
287	/* Prevent child from being added more than once. */
288	if (device_find_child(parent, driver->name, -1) != NULL)
289		return;
290
291	if (pci_get_devid(parent) == GLXIIC_CS5536_DEV_ID) {
292		if (device_add_child(parent, driver->name, -1) == NULL)
293			device_printf(parent, "Could not add glxiic child\n");
294	}
295}
296
297static int
298glxiic_probe(device_t dev)
299{
300
301	if (resource_disabled("glxiic", device_get_unit(dev)))
302		return (ENXIO);
303
304	device_set_desc(dev, "AMD Geode CS5536 SMBus controller");
305
306	return (BUS_PROBE_DEFAULT);
307}
308
309static int
310glxiic_attach(device_t dev)
311{
312	struct glxiic_softc *sc;
313	struct sysctl_ctx_list *ctx;
314	struct sysctl_oid *tree;
315	int error, irq, unit;
316	uint32_t irq_map;
317	char tn[32];
318
319	sc = device_get_softc(dev);
320	sc->dev = dev;
321	sc->state = GLXIIC_STATE_IDLE;
322	error = 0;
323
324	GLXIIC_LOCK_INIT(sc);
325	callout_init_mtx(&sc->callout, &sc->mtx, 0);
326
327	sc->smb_rid = PCIR_BAR(0);
328	sc->smb_res = bus_alloc_resource_any(dev, SYS_RES_IOPORT, &sc->smb_rid,
329	    RF_ACTIVE);
330	if (sc->smb_res == NULL) {
331		device_printf(dev, "Could not allocate SMBus I/O port\n");
332		error = ENXIO;
333		goto out;
334	}
335
336	sc->gpio_rid = PCIR_BAR(1);
337	sc->gpio_res = bus_alloc_resource_any(dev, SYS_RES_IOPORT,
338	    &sc->gpio_rid, RF_SHAREABLE | RF_ACTIVE);
339	if (sc->gpio_res == NULL) {
340		device_printf(dev, "Could not allocate GPIO I/O port\n");
341		error = ENXIO;
342		goto out;
343	}
344
345	/* Ensure the controller is not enabled by firmware. */
346	glxiic_smb_disable(sc);
347
348	/* Read the existing IRQ map. */
349	irq_map = rdmsr(GLXIIC_MSR_PIC_YSEL_HIGH);
350	sc->old_irq = GLXIIC_MAP_TO_SMB_IRQ(irq_map);
351
352	unit = device_get_unit(dev);
353	if (resource_int_value("glxiic", unit, "irq", &irq) == 0) {
354		if (irq < 1 || irq > 15) {
355			device_printf(dev, "Bad value %d for glxiic.%d.irq\n",
356			    irq, unit);
357			error = ENXIO;
358			goto out;
359		}
360
361		if (bootverbose)
362			device_printf(dev, "Using irq %d set by hint\n", irq);
363	} else if (sc->old_irq != 0) {
364		if (bootverbose)
365			device_printf(dev, "Using irq %d set by firmware\n",
366			    irq);
367		irq = sc->old_irq;
368	} else {
369		device_printf(dev, "No irq mapped by firmware");
370		printf(" and no glxiic.%d.irq hint provided\n", unit);
371		error = ENXIO;
372		goto out;
373	}
374
375	/* Map the SMBus interrupt to the requested legacy IRQ. */
376	glxiic_smb_map_interrupt(irq);
377
378	sc->irq_rid = 0;
379	sc->irq_res = bus_alloc_resource(dev, SYS_RES_IRQ, &sc->irq_rid,
380	    irq, irq, 1, RF_SHAREABLE | RF_ACTIVE);
381	if (sc->irq_res == NULL) {
382		device_printf(dev, "Could not allocate IRQ %d\n", irq);
383		error = ENXIO;
384		goto out;
385	}
386
387	error = bus_setup_intr(dev, sc->irq_res, INTR_TYPE_MISC | INTR_MPSAFE,
388	    NULL, glxiic_intr, sc, &(sc->irq_handler));
389	if (error != 0) {
390		device_printf(dev, "Could not setup IRQ handler\n");
391		error = ENXIO;
392		goto out;
393	}
394
395	if ((sc->iicbus = device_add_child(dev, "iicbus", -1)) == NULL) {
396		device_printf(dev, "Could not allocate iicbus instance\n");
397		error = ENXIO;
398		goto out;
399	}
400
401	ctx = device_get_sysctl_ctx(dev);
402	tree = device_get_sysctl_tree(dev);
403
404	sc->timeout = GLXIIC_DEFAULT_TIMEOUT;
405	snprintf(tn, sizeof(tn), "dev.glxiic.%d.timeout", unit);
406	TUNABLE_INT_FETCH(tn, &sc->timeout);
407	SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
408	    "timeout", CTLFLAG_RW | CTLFLAG_TUN, &sc->timeout, 0,
409	    "activity timeout in ms");
410
411	glxiic_gpio_enable(sc);
412	glxiic_smb_enable(sc, IIC_FASTEST, 0);
413
414	error = bus_generic_attach(dev);
415	if (error != 0) {
416		device_printf(dev, "Could not probe and attach children\n");
417		error = ENXIO;
418	}
419out:
420	if (error != 0) {
421		callout_drain(&sc->callout);
422
423		if (sc->iicbus != NULL)
424			device_delete_child(dev, sc->iicbus);
425		if (sc->smb_res != NULL) {
426			glxiic_smb_disable(sc);
427			bus_release_resource(dev, SYS_RES_IOPORT, sc->smb_rid,
428			    sc->smb_res);
429		}
430		if (sc->gpio_res != NULL) {
431			glxiic_gpio_disable(sc);
432			bus_release_resource(dev, SYS_RES_IOPORT, sc->gpio_rid,
433			    sc->gpio_res);
434		}
435		if (sc->irq_handler != NULL)
436			bus_teardown_intr(dev, sc->irq_res, sc->irq_handler);
437		if (sc->irq_res != NULL)
438			bus_release_resource(dev, SYS_RES_IRQ, sc->irq_rid,
439			    sc->irq_res);
440
441		/* Restore the old SMBus interrupt mapping. */
442		glxiic_smb_map_interrupt(sc->old_irq);
443
444		GLXIIC_LOCK_DESTROY(sc);
445	}
446
447	return (error);
448}
449
450static int
451glxiic_detach(device_t dev)
452{
453	struct glxiic_softc *sc;
454	int error;
455
456	sc = device_get_softc(dev);
457
458	error = bus_generic_detach(dev);
459	if (error != 0)
460		goto out;
461	if (sc->iicbus != NULL)
462		error = device_delete_child(dev, sc->iicbus);
463
464out:
465	callout_drain(&sc->callout);
466
467	if (sc->smb_res != NULL) {
468		glxiic_smb_disable(sc);
469		bus_release_resource(dev, SYS_RES_IOPORT, sc->smb_rid,
470		    sc->smb_res);
471	}
472	if (sc->gpio_res != NULL) {
473		glxiic_gpio_disable(sc);
474		bus_release_resource(dev, SYS_RES_IOPORT, sc->gpio_rid,
475		    sc->gpio_res);
476	}
477	if (sc->irq_handler != NULL)
478		bus_teardown_intr(dev, sc->irq_res, sc->irq_handler);
479	if (sc->irq_res != NULL)
480		bus_release_resource(dev, SYS_RES_IRQ, sc->irq_rid,
481		    sc->irq_res);
482
483	/* Restore the old SMBus interrupt mapping. */
484	glxiic_smb_map_interrupt(sc->old_irq);
485
486	GLXIIC_LOCK_DESTROY(sc);
487
488	return (error);
489}
490
491static uint8_t
492glxiic_read_status_locked(struct glxiic_softc *sc)
493{
494	uint8_t status;
495
496	GLXIIC_ASSERT_LOCKED(sc);
497
498	status = bus_read_1(sc->smb_res, GLXIIC_SMB_STS);
499
500	/* Clear all status flags except SDAST and STASTR after reading. */
501	bus_write_1(sc->smb_res, GLXIIC_SMB_STS, (GLXIIC_SMB_STS_SLVSTP_BIT |
502		GLXIIC_SMB_STS_BER_BIT | GLXIIC_SMB_STS_NEGACK_BIT |
503		GLXIIC_SMB_STS_NMATCH_BIT));
504
505	return (status);
506}
507
508static void
509glxiic_stop_locked(struct glxiic_softc *sc)
510{
511	uint8_t status, ctrl1;
512
513	GLXIIC_ASSERT_LOCKED(sc);
514
515	status = glxiic_read_status_locked(sc);
516
517	ctrl1 = bus_read_1(sc->smb_res, GLXIIC_SMB_CTRL1);
518	bus_write_1(sc->smb_res, GLXIIC_SMB_CTRL1,
519	    ctrl1 | GLXIIC_SMB_CTRL1_STOP_BIT);
520
521	/*
522	 * Perform a dummy read of SDA in master receive mode to clear
523	 * SDAST if set.
524	 */
525	if ((status & GLXIIC_SMB_STS_XMIT_BIT) == 0 &&
526	    (status & GLXIIC_SMB_STS_SDAST_BIT) != 0)
527	 	bus_read_1(sc->smb_res, GLXIIC_SMB_SDA);
528
529	/* Check stall after start bit and clear if needed */
530	if ((status & GLXIIC_SMB_STS_STASTR_BIT) != 0) {
531		bus_write_1(sc->smb_res, GLXIIC_SMB_STS,
532		    GLXIIC_SMB_STS_STASTR_BIT);
533	}
534}
535
536static void
537glxiic_timeout(void *arg)
538{
539	struct glxiic_softc *sc;
540	uint8_t error;
541
542	sc = (struct glxiic_softc *)arg;
543
544	GLXIIC_DEBUG_LOG("timeout in state %d", sc->state);
545
546	if (glxiic_state_table[sc->state].master) {
547		sc->error = IIC_ETIMEOUT;
548		GLXIIC_WAKEUP(sc);
549	} else {
550		error = IIC_ETIMEOUT;
551		iicbus_intr(sc->iicbus, INTR_ERROR, &error);
552	}
553
554	glxiic_smb_disable(sc);
555	glxiic_smb_enable(sc, IIC_UNKNOWN, sc->addr);
556	glxiic_set_state_locked(sc, GLXIIC_STATE_IDLE);
557}
558
559static void
560glxiic_start_timeout_locked(struct glxiic_softc *sc)
561{
562
563	GLXIIC_ASSERT_LOCKED(sc);
564
565	callout_reset(&sc->callout, sc->timeout * 1000 / hz, glxiic_timeout,
566	    sc);
567}
568
569static void
570glxiic_set_state_locked(struct glxiic_softc *sc, glxiic_state_t state)
571{
572
573	GLXIIC_ASSERT_LOCKED(sc);
574
575	if (state == GLXIIC_STATE_IDLE)
576		callout_stop(&sc->callout);
577	else if (sc->timeout > 0)
578		glxiic_start_timeout_locked(sc);
579
580	sc->state = state;
581}
582
583static int
584glxiic_handle_slave_match_locked(struct glxiic_softc *sc, uint8_t status)
585{
586	uint8_t ctrl_sts, addr;
587
588	GLXIIC_ASSERT_LOCKED(sc);
589
590	ctrl_sts = bus_read_1(sc->smb_res, GLXIIC_SMB_CTRL_STS);
591
592	if ((ctrl_sts & GLXIIC_SMB_CTRL_STS_MATCH_BIT) != 0) {
593		if ((status & GLXIIC_SMB_STS_XMIT_BIT) != 0) {
594			addr = sc->addr | LSB;
595			glxiic_set_state_locked(sc,
596			    GLXIIC_STATE_SLAVE_TX);
597		} else {
598			addr = sc->addr & ~LSB;
599			glxiic_set_state_locked(sc,
600			    GLXIIC_STATE_SLAVE_RX);
601		}
602		iicbus_intr(sc->iicbus, INTR_START, &addr);
603	} else if ((ctrl_sts & GLXIIC_SMB_CTRL_STS_GCMTCH_BIT) != 0) {
604		addr = 0;
605		glxiic_set_state_locked(sc, GLXIIC_STATE_SLAVE_RX);
606		iicbus_intr(sc->iicbus, INTR_GENERAL, &addr);
607	} else {
608		GLXIIC_DEBUG_LOG("unknown slave match");
609		return (IIC_ESTATUS);
610	}
611
612	return (IIC_NOERR);
613}
614
615static int
616glxiic_state_idle_callback(struct glxiic_softc *sc, uint8_t status)
617{
618
619	GLXIIC_ASSERT_LOCKED(sc);
620
621	if ((status & GLXIIC_SMB_STS_BER_BIT) != 0) {
622		GLXIIC_DEBUG_LOG("bus error in idle");
623		return (IIC_EBUSERR);
624	}
625
626	if ((status & GLXIIC_SMB_STS_NMATCH_BIT) != 0) {
627		return (glxiic_handle_slave_match_locked(sc, status));
628	}
629
630	return (IIC_NOERR);
631}
632
633static int
634glxiic_state_slave_tx_callback(struct glxiic_softc *sc, uint8_t status)
635{
636	uint8_t data;
637
638	GLXIIC_ASSERT_LOCKED(sc);
639
640	if ((status & GLXIIC_SMB_STS_BER_BIT) != 0) {
641		GLXIIC_DEBUG_LOG("bus error in slave tx");
642		return (IIC_EBUSERR);
643	}
644
645	if ((status & GLXIIC_SMB_STS_SLVSTP_BIT) != 0) {
646		iicbus_intr(sc->iicbus, INTR_STOP, NULL);
647		glxiic_set_state_locked(sc, GLXIIC_STATE_IDLE);
648		return (IIC_NOERR);
649	}
650
651	if ((status & GLXIIC_SMB_STS_NEGACK_BIT) != 0) {
652		iicbus_intr(sc->iicbus, INTR_NOACK, NULL);
653		return (IIC_NOERR);
654	}
655
656	if ((status & GLXIIC_SMB_STS_NMATCH_BIT) != 0) {
657		/* Handle repeated start in slave mode. */
658		return (glxiic_handle_slave_match_locked(sc, status));
659	}
660
661	if ((status & GLXIIC_SMB_STS_SDAST_BIT) == 0) {
662		GLXIIC_DEBUG_LOG("not awaiting data in slave tx");
663		return (IIC_ESTATUS);
664	}
665
666	iicbus_intr(sc->iicbus, INTR_TRANSMIT, &data);
667	bus_write_1(sc->smb_res, GLXIIC_SMB_SDA, data);
668
669	glxiic_start_timeout_locked(sc);
670
671	return (IIC_NOERR);
672}
673
674static int
675glxiic_state_slave_rx_callback(struct glxiic_softc *sc, uint8_t status)
676{
677	uint8_t data;
678
679	GLXIIC_ASSERT_LOCKED(sc);
680
681	if ((status & GLXIIC_SMB_STS_BER_BIT) != 0) {
682		GLXIIC_DEBUG_LOG("bus error in slave rx");
683		return (IIC_EBUSERR);
684	}
685
686	if ((status & GLXIIC_SMB_STS_SLVSTP_BIT) != 0) {
687		iicbus_intr(sc->iicbus, INTR_STOP, NULL);
688		glxiic_set_state_locked(sc, GLXIIC_STATE_IDLE);
689		return (IIC_NOERR);
690	}
691
692	if ((status & GLXIIC_SMB_STS_NMATCH_BIT) != 0) {
693		/* Handle repeated start in slave mode. */
694		return (glxiic_handle_slave_match_locked(sc, status));
695	}
696
697	if ((status & GLXIIC_SMB_STS_SDAST_BIT) == 0) {
698		GLXIIC_DEBUG_LOG("no pending data in slave rx");
699		return (IIC_ESTATUS);
700	}
701
702	data = bus_read_1(sc->smb_res, GLXIIC_SMB_SDA);
703	iicbus_intr(sc->iicbus, INTR_RECEIVE, &data);
704
705	glxiic_start_timeout_locked(sc);
706
707	return (IIC_NOERR);
708}
709
710static int
711glxiic_state_master_addr_callback(struct glxiic_softc *sc, uint8_t status)
712{
713	uint8_t slave;
714
715	GLXIIC_ASSERT_LOCKED(sc);
716
717	if ((status & GLXIIC_SMB_STS_BER_BIT) != 0) {
718		GLXIIC_DEBUG_LOG("bus error after master start");
719		return (IIC_EBUSERR);
720	}
721
722	if ((status & GLXIIC_SMB_STS_MASTER_BIT) == 0) {
723		GLXIIC_DEBUG_LOG("not bus master after master start");
724		return (IIC_ESTATUS);
725	}
726
727	if ((status & GLXIIC_SMB_STS_SDAST_BIT) == 0) {
728		GLXIIC_DEBUG_LOG("not awaiting address in master addr");
729		return (IIC_ESTATUS);
730	}
731
732	if ((sc->msg->flags & IIC_M_RD) != 0) {
733		slave = sc->msg->slave | LSB;
734		glxiic_set_state_locked(sc, GLXIIC_STATE_MASTER_RX);
735	} else {
736		slave = sc->msg->slave & ~LSB;
737		glxiic_set_state_locked(sc, GLXIIC_STATE_MASTER_TX);
738	}
739
740	sc->data = sc->msg->buf;
741	sc->ndata = sc->msg->len;
742
743	/* Handle address-only transfer. */
744	if (sc->ndata == 0)
745		glxiic_set_state_locked(sc, GLXIIC_STATE_MASTER_STOP);
746
747	bus_write_1(sc->smb_res, GLXIIC_SMB_SDA, slave);
748
749	return (IIC_NOERR);
750}
751
752static int
753glxiic_state_master_tx_callback(struct glxiic_softc *sc, uint8_t status)
754{
755
756	GLXIIC_ASSERT_LOCKED(sc);
757
758	if ((status & GLXIIC_SMB_STS_BER_BIT) != 0) {
759		GLXIIC_DEBUG_LOG("bus error in master tx");
760		return (IIC_EBUSERR);
761	}
762
763	if ((status & GLXIIC_SMB_STS_MASTER_BIT) == 0) {
764		GLXIIC_DEBUG_LOG("not bus master in master tx");
765		return (IIC_ESTATUS);
766	}
767
768	if ((status & GLXIIC_SMB_STS_NEGACK_BIT) != 0) {
769		GLXIIC_DEBUG_LOG("slave nack in master tx");
770		return (IIC_ENOACK);
771	}
772
773	if ((status & GLXIIC_SMB_STS_STASTR_BIT) != 0) {
774		bus_write_1(sc->smb_res, GLXIIC_SMB_STS,
775		    GLXIIC_SMB_STS_STASTR_BIT);
776	}
777
778	if ((status & GLXIIC_SMB_STS_SDAST_BIT) == 0) {
779		GLXIIC_DEBUG_LOG("not awaiting data in master tx");
780		return (IIC_ESTATUS);
781	}
782
783	bus_write_1(sc->smb_res, GLXIIC_SMB_SDA, *sc->data++);
784	if (--sc->ndata == 0)
785		glxiic_set_state_locked(sc, GLXIIC_STATE_MASTER_STOP);
786	else
787		glxiic_start_timeout_locked(sc);
788
789	return (IIC_NOERR);
790}
791
792static int
793glxiic_state_master_rx_callback(struct glxiic_softc *sc, uint8_t status)
794{
795	uint8_t ctrl1;
796
797	GLXIIC_ASSERT_LOCKED(sc);
798
799	if ((status & GLXIIC_SMB_STS_BER_BIT) != 0) {
800		GLXIIC_DEBUG_LOG("bus error in master rx");
801		return (IIC_EBUSERR);
802	}
803
804	if ((status & GLXIIC_SMB_STS_MASTER_BIT) == 0) {
805		GLXIIC_DEBUG_LOG("not bus master in master rx");
806		return (IIC_ESTATUS);
807	}
808
809	if ((status & GLXIIC_SMB_STS_NEGACK_BIT) != 0) {
810		GLXIIC_DEBUG_LOG("slave nack in rx");
811		return (IIC_ENOACK);
812	}
813
814	if (sc->ndata == 1) {
815		/* Last byte from slave, set NACK. */
816		ctrl1 = bus_read_1(sc->smb_res, GLXIIC_SMB_CTRL1);
817		bus_write_1(sc->smb_res, GLXIIC_SMB_CTRL1,
818		    ctrl1 | GLXIIC_SMB_CTRL1_ACK_BIT);
819	}
820
821	if ((status & GLXIIC_SMB_STS_STASTR_BIT) != 0) {
822		/* Bus is stalled, clear and wait for data. */
823		bus_write_1(sc->smb_res, GLXIIC_SMB_STS,
824		    GLXIIC_SMB_STS_STASTR_BIT);
825		return (IIC_NOERR);
826	}
827
828	if ((status & GLXIIC_SMB_STS_SDAST_BIT) == 0) {
829		GLXIIC_DEBUG_LOG("no pending data in master rx");
830		return (IIC_ESTATUS);
831	}
832
833	*sc->data++ = bus_read_1(sc->smb_res, GLXIIC_SMB_SDA);
834	if (--sc->ndata == 0) {
835		/* Proceed with stop on reading last byte. */
836		glxiic_set_state_locked(sc, GLXIIC_STATE_MASTER_STOP);
837		return (glxiic_state_table[sc->state].callback(sc, status));
838	}
839
840	glxiic_start_timeout_locked(sc);
841
842	return (IIC_NOERR);
843}
844
845static int
846glxiic_state_master_stop_callback(struct glxiic_softc *sc, uint8_t status)
847{
848	uint8_t ctrl1;
849
850	GLXIIC_ASSERT_LOCKED(sc);
851
852	if ((status & GLXIIC_SMB_STS_BER_BIT) != 0) {
853		GLXIIC_DEBUG_LOG("bus error in master stop");
854		return (IIC_EBUSERR);
855	}
856
857	if ((status & GLXIIC_SMB_STS_MASTER_BIT) == 0) {
858		GLXIIC_DEBUG_LOG("not bus master in master stop");
859		return (IIC_ESTATUS);
860	}
861
862	if ((status & GLXIIC_SMB_STS_NEGACK_BIT) != 0) {
863		GLXIIC_DEBUG_LOG("slave nack in master stop");
864		return (IIC_ENOACK);
865	}
866
867	if (--sc->nmsgs > 0) {
868		/* Start transfer of next message. */
869		if ((sc->msg->flags & IIC_M_NOSTOP) == 0) {
870			glxiic_stop_locked(sc);
871		}
872
873		ctrl1 = bus_read_1(sc->smb_res, GLXIIC_SMB_CTRL1);
874		bus_write_1(sc->smb_res, GLXIIC_SMB_CTRL1,
875		    ctrl1 | GLXIIC_SMB_CTRL1_START_BIT);
876
877		glxiic_set_state_locked(sc, GLXIIC_STATE_MASTER_ADDR);
878		sc->msg++;
879	} else {
880		/* Last message. */
881		glxiic_stop_locked(sc);
882		glxiic_set_state_locked(sc, GLXIIC_STATE_IDLE);
883		sc->error = IIC_NOERR;
884		GLXIIC_WAKEUP(sc);
885	}
886
887	return (IIC_NOERR);
888}
889
890static void
891glxiic_intr(void *arg)
892{
893	struct glxiic_softc *sc;
894	int error;
895	uint8_t status, data;
896
897	sc = (struct glxiic_softc *)arg;
898
899	GLXIIC_LOCK(sc);
900
901	status = glxiic_read_status_locked(sc);
902
903	/* Check if this interrupt originated from the SMBus. */
904	if ((status &
905		~(GLXIIC_SMB_STS_MASTER_BIT | GLXIIC_SMB_STS_XMIT_BIT)) != 0) {
906
907		error = glxiic_state_table[sc->state].callback(sc, status);
908
909		if (error != IIC_NOERR) {
910			if (glxiic_state_table[sc->state].master) {
911				glxiic_stop_locked(sc);
912				glxiic_set_state_locked(sc, GLXIIC_STATE_IDLE);
913				sc->error = error;
914				GLXIIC_WAKEUP(sc);
915			} else {
916				data = error & 0xff;
917				iicbus_intr(sc->iicbus, INTR_ERROR, &data);
918				glxiic_set_state_locked(sc, GLXIIC_STATE_IDLE);
919			}
920		}
921	}
922
923	GLXIIC_UNLOCK(sc);
924}
925
926static int
927glxiic_reset(device_t dev, u_char speed, u_char addr, u_char *oldaddr)
928{
929	struct glxiic_softc *sc;
930
931	sc = device_get_softc(dev);
932
933	GLXIIC_LOCK(sc);
934
935	if (oldaddr != NULL)
936		*oldaddr = sc->addr;
937	sc->addr = addr;
938
939	/* A disable/enable cycle resets the controller. */
940	glxiic_smb_disable(sc);
941	glxiic_smb_enable(sc, speed, addr);
942
943	if (glxiic_state_table[sc->state].master) {
944		sc->error = IIC_ESTATUS;
945		GLXIIC_WAKEUP(sc);
946	}
947	glxiic_set_state_locked(sc, GLXIIC_STATE_IDLE);
948
949	GLXIIC_UNLOCK(sc);
950
951	return (IIC_NOERR);
952}
953
954static int
955glxiic_transfer(device_t dev, struct iic_msg *msgs, uint32_t nmsgs)
956{
957	struct glxiic_softc *sc;
958	int error;
959	uint8_t ctrl1;
960
961	sc = device_get_softc(dev);
962
963	GLXIIC_LOCK(sc);
964
965	if (sc->state != GLXIIC_STATE_IDLE) {
966		error = IIC_EBUSBSY;
967		goto out;
968	}
969
970	sc->msg = msgs;
971	sc->nmsgs = nmsgs;
972	glxiic_set_state_locked(sc, GLXIIC_STATE_MASTER_ADDR);
973
974	/* Set start bit and let glxiic_intr() handle the transfer. */
975	ctrl1 = bus_read_1(sc->smb_res, GLXIIC_SMB_CTRL1);
976	bus_write_1(sc->smb_res, GLXIIC_SMB_CTRL1,
977	    ctrl1 | GLXIIC_SMB_CTRL1_START_BIT);
978
979	GLXIIC_SLEEP(sc);
980	error = sc->error;
981out:
982	GLXIIC_UNLOCK(sc);
983
984	return (error);
985}
986
987static void
988glxiic_smb_map_interrupt(int irq)
989{
990	uint32_t irq_map;
991	int old_irq;
992
993	/* Protect the read-modify-write operation. */
994	critical_enter();
995
996	irq_map = rdmsr(GLXIIC_MSR_PIC_YSEL_HIGH);
997	old_irq = GLXIIC_MAP_TO_SMB_IRQ(irq_map);
998
999	if (irq != old_irq) {
1000		irq_map &= ~GLXIIC_SMB_IRQ_TO_MAP(old_irq);
1001		irq_map |= GLXIIC_SMB_IRQ_TO_MAP(irq);
1002		wrmsr(GLXIIC_MSR_PIC_YSEL_HIGH, irq_map);
1003	}
1004
1005	critical_exit();
1006}
1007
1008static void
1009glxiic_gpio_enable(struct glxiic_softc *sc)
1010{
1011
1012	bus_write_4(sc->gpio_res, GLXIIC_GPIOL_IN_AUX1_SEL,
1013	    GLXIIC_GPIO_14_15_ENABLE);
1014	bus_write_4(sc->gpio_res, GLXIIC_GPIOL_OUT_AUX1_SEL,
1015	    GLXIIC_GPIO_14_15_ENABLE);
1016}
1017
1018static void
1019glxiic_gpio_disable(struct glxiic_softc *sc)
1020{
1021
1022	bus_write_4(sc->gpio_res, GLXIIC_GPIOL_OUT_AUX1_SEL,
1023	    GLXIIC_GPIO_14_15_DISABLE);
1024	bus_write_4(sc->gpio_res, GLXIIC_GPIOL_IN_AUX1_SEL,
1025	    GLXIIC_GPIO_14_15_DISABLE);
1026}
1027
1028static void
1029glxiic_smb_enable(struct glxiic_softc *sc, uint8_t speed, uint8_t addr)
1030{
1031	uint8_t ctrl1;
1032
1033	ctrl1 = 0;
1034
1035	switch (speed) {
1036	case IIC_SLOW:
1037		sc->sclfrq = GLXIIC_SLOW;
1038		break;
1039	case IIC_FAST:
1040		sc->sclfrq = GLXIIC_FAST;
1041		break;
1042	case IIC_FASTEST:
1043		sc->sclfrq = GLXIIC_FASTEST;
1044		break;
1045	case IIC_UNKNOWN:
1046	default:
1047		/* Reuse last frequency. */
1048		break;
1049	}
1050
1051	/* Set bus speed and enable controller. */
1052	bus_write_2(sc->smb_res, GLXIIC_SMB_CTRL2,
1053	    GLXIIC_SCLFRQ(sc->sclfrq) | GLXIIC_SMB_CTRL2_EN_BIT);
1054
1055	if (addr != 0) {
1056		/* Enable new match and global call match interrupts. */
1057		ctrl1 |= GLXIIC_SMB_CTRL1_NMINTE_BIT |
1058			GLXIIC_SMB_CTRL1_GCMEN_BIT;
1059		bus_write_1(sc->smb_res, GLXIIC_SMB_ADDR,
1060		    GLXIIC_SMB_ADDR_SAEN_BIT | GLXIIC_SMBADDR(addr));
1061	} else {
1062		bus_write_1(sc->smb_res, GLXIIC_SMB_ADDR, 0);
1063	}
1064
1065	/* Enable stall after start and interrupt. */
1066	bus_write_1(sc->smb_res, GLXIIC_SMB_CTRL1,
1067	    ctrl1 | GLXIIC_SMB_CTRL1_STASTRE_BIT | GLXIIC_SMB_CTRL1_INTEN_BIT);
1068}
1069
1070static void
1071glxiic_smb_disable(struct glxiic_softc *sc)
1072{
1073	uint16_t sclfrq;
1074
1075	sclfrq = bus_read_2(sc->smb_res, GLXIIC_SMB_CTRL2);
1076	bus_write_2(sc->smb_res, GLXIIC_SMB_CTRL2,
1077	    sclfrq & ~GLXIIC_SMB_CTRL2_EN_BIT);
1078}
1079