xref: /freebsd/sys/dev/acpica/acpi_ec.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1 /*-
2  * Copyright (c) 2003-2007 Nate Lawson
3  * Copyright (c) 2000 Michael Smith
4  * Copyright (c) 2000 BSDi
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 #include "opt_acpi.h"
31 #include <sys/param.h>
32 #include <sys/kernel.h>
33 #include <sys/ktr.h>
34 #include <sys/bus.h>
35 #include <sys/lock.h>
36 #include <sys/malloc.h>
37 #include <sys/module.h>
38 #include <sys/sx.h>
39 
40 #include <machine/bus.h>
41 #include <machine/resource.h>
42 #include <sys/rman.h>
43 
44 #include <contrib/dev/acpica/include/acpi.h>
45 #include <contrib/dev/acpica/include/accommon.h>
46 
47 #include <dev/acpica/acpivar.h>
48 
49 /* Hooks for the ACPI CA debugging infrastructure */
50 #define _COMPONENT	ACPI_EC
51 ACPI_MODULE_NAME("EC")
52 
53 /*
54  * EC_COMMAND:
55  * -----------
56  */
57 typedef UINT8				EC_COMMAND;
58 
59 #define EC_COMMAND_UNKNOWN		((EC_COMMAND) 0x00)
60 #define EC_COMMAND_READ			((EC_COMMAND) 0x80)
61 #define EC_COMMAND_WRITE		((EC_COMMAND) 0x81)
62 #define EC_COMMAND_BURST_ENABLE		((EC_COMMAND) 0x82)
63 #define EC_COMMAND_BURST_DISABLE	((EC_COMMAND) 0x83)
64 #define EC_COMMAND_QUERY		((EC_COMMAND) 0x84)
65 
66 /*
67  * EC_STATUS:
68  * ----------
69  * The encoding of the EC status register is illustrated below.
70  * Note that a set bit (1) indicates the property is TRUE
71  * (e.g. if bit 0 is set then the output buffer is full).
72  * +-+-+-+-+-+-+-+-+
73  * |7|6|5|4|3|2|1|0|
74  * +-+-+-+-+-+-+-+-+
75  *  | | | | | | | |
76  *  | | | | | | | +- Output Buffer Full?
77  *  | | | | | | +--- Input Buffer Full?
78  *  | | | | | +----- <reserved>
79  *  | | | | +------- Data Register is Command Byte?
80  *  | | | +--------- Burst Mode Enabled?
81  *  | | +----------- SCI Event?
82  *  | +------------- SMI Event?
83  *  +--------------- <reserved>
84  *
85  */
86 typedef UINT8				EC_STATUS;
87 
88 #define EC_FLAG_OUTPUT_BUFFER		((EC_STATUS) 0x01)
89 #define EC_FLAG_INPUT_BUFFER		((EC_STATUS) 0x02)
90 #define EC_FLAG_DATA_IS_CMD		((EC_STATUS) 0x08)
91 #define EC_FLAG_BURST_MODE		((EC_STATUS) 0x10)
92 
93 /*
94  * EC_EVENT:
95  * ---------
96  */
97 typedef UINT8				EC_EVENT;
98 
99 #define EC_EVENT_UNKNOWN		((EC_EVENT) 0x00)
100 #define EC_EVENT_OUTPUT_BUFFER_FULL	((EC_EVENT) 0x01)
101 #define EC_EVENT_INPUT_BUFFER_EMPTY	((EC_EVENT) 0x02)
102 #define EC_EVENT_SCI			((EC_EVENT) 0x20)
103 #define EC_EVENT_SMI			((EC_EVENT) 0x40)
104 
105 /* Data byte returned after burst enable indicating it was successful. */
106 #define EC_BURST_ACK			0x90
107 
108 /*
109  * Register access primitives
110  */
111 #define EC_GET_DATA(sc)							\
112 	bus_space_read_1((sc)->ec_data_tag, (sc)->ec_data_handle, 0)
113 
114 #define EC_SET_DATA(sc, v)						\
115 	bus_space_write_1((sc)->ec_data_tag, (sc)->ec_data_handle, 0, (v))
116 
117 #define EC_GET_CSR(sc)							\
118 	bus_space_read_1((sc)->ec_csr_tag, (sc)->ec_csr_handle, 0)
119 
120 #define EC_SET_CSR(sc, v)						\
121 	bus_space_write_1((sc)->ec_csr_tag, (sc)->ec_csr_handle, 0, (v))
122 
123 /* Additional params to pass from the probe routine */
124 struct acpi_ec_params {
125     int		glk;
126     int		gpe_bit;
127     ACPI_HANDLE	gpe_handle;
128     int		uid;
129 };
130 
131 /*
132  * Driver softc.
133  */
134 struct acpi_ec_softc {
135     device_t		ec_dev;
136     ACPI_HANDLE		ec_handle;
137     int			ec_uid;
138     ACPI_HANDLE		ec_gpehandle;
139     UINT8		ec_gpebit;
140 
141     int			ec_data_rid;
142     struct resource	*ec_data_res;
143     bus_space_tag_t	ec_data_tag;
144     bus_space_handle_t	ec_data_handle;
145 
146     int			ec_csr_rid;
147     struct resource	*ec_csr_res;
148     bus_space_tag_t	ec_csr_tag;
149     bus_space_handle_t	ec_csr_handle;
150 
151     int			ec_glk;
152     int			ec_glkhandle;
153     int			ec_burstactive;
154     int			ec_sci_pend;
155     volatile u_int	ec_gencount;
156     int			ec_suspending;
157 };
158 
159 /*
160  * XXX njl
161  * I couldn't find it in the spec but other implementations also use a
162  * value of 1 ms for the time to acquire global lock.
163  */
164 #define EC_LOCK_TIMEOUT	1000
165 
166 /* Default delay in microseconds between each run of the status polling loop. */
167 #define EC_POLL_DELAY	50
168 
169 /* Total time in ms spent waiting for a response from EC. */
170 #define EC_TIMEOUT	750
171 
172 #define EVENT_READY(event, status)			\
173 	(((event) == EC_EVENT_OUTPUT_BUFFER_FULL &&	\
174 	 ((status) & EC_FLAG_OUTPUT_BUFFER) != 0) ||	\
175 	 ((event) == EC_EVENT_INPUT_BUFFER_EMPTY && 	\
176 	 ((status) & EC_FLAG_INPUT_BUFFER) == 0))
177 
178 ACPI_SERIAL_DECL(ec, "ACPI embedded controller");
179 
180 static SYSCTL_NODE(_debug_acpi, OID_AUTO, ec,
181     CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
182     "EC debugging");
183 
184 static int	ec_burst_mode;
185 SYSCTL_INT(_debug_acpi_ec, OID_AUTO, burst, CTLFLAG_RWTUN, &ec_burst_mode, 0,
186     "Enable use of burst mode (faster for nearly all systems)");
187 static int	ec_polled_mode;
188 SYSCTL_INT(_debug_acpi_ec, OID_AUTO, polled, CTLFLAG_RWTUN, &ec_polled_mode, 0,
189     "Force use of polled mode (only if interrupt mode doesn't work)");
190 static int	ec_timeout = EC_TIMEOUT;
191 SYSCTL_INT(_debug_acpi_ec, OID_AUTO, timeout, CTLFLAG_RWTUN, &ec_timeout,
192     EC_TIMEOUT, "Total time spent waiting for a response (poll+sleep)");
193 
194 static ACPI_STATUS
195 EcLock(struct acpi_ec_softc *sc)
196 {
197     ACPI_STATUS	status;
198 
199     /* If _GLK is non-zero, acquire the global lock. */
200     status = AE_OK;
201     if (sc->ec_glk) {
202 	status = AcpiAcquireGlobalLock(EC_LOCK_TIMEOUT, &sc->ec_glkhandle);
203 	if (ACPI_FAILURE(status))
204 	    return (status);
205     }
206     ACPI_SERIAL_BEGIN(ec);
207     return (status);
208 }
209 
210 static void
211 EcUnlock(struct acpi_ec_softc *sc)
212 {
213     ACPI_SERIAL_END(ec);
214     if (sc->ec_glk)
215 	AcpiReleaseGlobalLock(sc->ec_glkhandle);
216 }
217 
218 static UINT32		EcGpeHandler(ACPI_HANDLE, UINT32, void *);
219 static ACPI_STATUS	EcSpaceSetup(ACPI_HANDLE Region, UINT32 Function,
220 				void *Context, void **return_Context);
221 static ACPI_STATUS	EcSpaceHandler(UINT32 Function,
222 				ACPI_PHYSICAL_ADDRESS Address,
223 				UINT32 Width, UINT64 *Value,
224 				void *Context, void *RegionContext);
225 static ACPI_STATUS	EcWaitEvent(struct acpi_ec_softc *sc, EC_EVENT Event,
226 				u_int gen_count);
227 static ACPI_STATUS	EcCommand(struct acpi_ec_softc *sc, EC_COMMAND cmd);
228 static ACPI_STATUS	EcRead(struct acpi_ec_softc *sc, UINT8 Address,
229 				UINT8 *Data);
230 static ACPI_STATUS	EcWrite(struct acpi_ec_softc *sc, UINT8 Address,
231 				UINT8 Data);
232 static int		acpi_ec_probe(device_t dev);
233 static int		acpi_ec_attach(device_t dev);
234 static int		acpi_ec_suspend(device_t dev);
235 static int		acpi_ec_resume(device_t dev);
236 static int		acpi_ec_shutdown(device_t dev);
237 static int		acpi_ec_read_method(device_t dev, u_int addr,
238 				UINT64 *val, int width);
239 static int		acpi_ec_write_method(device_t dev, u_int addr,
240 				UINT64 val, int width);
241 
242 static device_method_t acpi_ec_methods[] = {
243     /* Device interface */
244     DEVMETHOD(device_probe,	acpi_ec_probe),
245     DEVMETHOD(device_attach,	acpi_ec_attach),
246     DEVMETHOD(device_suspend,	acpi_ec_suspend),
247     DEVMETHOD(device_resume,	acpi_ec_resume),
248     DEVMETHOD(device_shutdown,	acpi_ec_shutdown),
249 
250     /* Embedded controller interface */
251     DEVMETHOD(acpi_ec_read,	acpi_ec_read_method),
252     DEVMETHOD(acpi_ec_write,	acpi_ec_write_method),
253 
254     DEVMETHOD_END
255 };
256 
257 static driver_t acpi_ec_driver = {
258     "acpi_ec",
259     acpi_ec_methods,
260     sizeof(struct acpi_ec_softc),
261 };
262 
263 DRIVER_MODULE(acpi_ec, acpi, acpi_ec_driver, 0, 0);
264 MODULE_DEPEND(acpi_ec, acpi, 1, 1, 1);
265 
266 /*
267  * Look for an ECDT and if we find one, set up default GPE and
268  * space handlers to catch attempts to access EC space before
269  * we have a real driver instance in place.
270  *
271  * TODO: Some old Gateway laptops need us to fake up an ECDT or
272  * otherwise attach early so that _REG methods can run.
273  */
274 void
275 acpi_ec_ecdt_probe(device_t parent)
276 {
277     ACPI_TABLE_ECDT *ecdt;
278     ACPI_STATUS	     status;
279     device_t	     child;
280     ACPI_HANDLE	     h;
281     struct acpi_ec_params *params;
282 
283     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
284 
285     /* Find and validate the ECDT. */
286     status = AcpiGetTable(ACPI_SIG_ECDT, 1, (ACPI_TABLE_HEADER **)&ecdt);
287     if (ACPI_FAILURE(status) ||
288 	ecdt->Control.BitWidth != 8 ||
289 	ecdt->Data.BitWidth != 8) {
290 	return;
291     }
292 
293     /* Create the child device with the given unit number. */
294     child = BUS_ADD_CHILD(parent, 3, "acpi_ec", ecdt->Uid);
295     if (child == NULL) {
296 	printf("%s: can't add child\n", __func__);
297 	return;
298     }
299 
300     /* Find and save the ACPI handle for this device. */
301     status = AcpiGetHandle(NULL, ecdt->Id, &h);
302     if (ACPI_FAILURE(status)) {
303 	device_delete_child(parent, child);
304 	printf("%s: can't get handle\n", __func__);
305 	return;
306     }
307     acpi_set_handle(child, h);
308 
309     /* Set the data and CSR register addresses. */
310     bus_set_resource(child, SYS_RES_IOPORT, 0, ecdt->Data.Address,
311 	/*count*/1);
312     bus_set_resource(child, SYS_RES_IOPORT, 1, ecdt->Control.Address,
313 	/*count*/1);
314 
315     /*
316      * Store values for the probe/attach routines to use.  Store the
317      * ECDT GPE bit and set the global lock flag according to _GLK.
318      * Note that it is not perfectly correct to be evaluating a method
319      * before initializing devices, but in practice this function
320      * should be safe to call at this point.
321      */
322     params = malloc(sizeof(struct acpi_ec_params), M_TEMP, M_WAITOK | M_ZERO);
323     params->gpe_handle = NULL;
324     params->gpe_bit = ecdt->Gpe;
325     params->uid = ecdt->Uid;
326     acpi_GetInteger(h, "_GLK", &params->glk);
327     acpi_set_private(child, params);
328 
329     /* Finish the attach process. */
330     if (device_probe_and_attach(child) != 0)
331 	device_delete_child(parent, child);
332 }
333 
334 static int
335 acpi_ec_probe(device_t dev)
336 {
337     ACPI_BUFFER buf;
338     ACPI_HANDLE h;
339     ACPI_OBJECT *obj;
340     ACPI_STATUS status;
341     device_t	peer;
342     char	desc[64];
343     int		ecdt;
344     int		ret, rc;
345     struct acpi_ec_params *params;
346     static char *ec_ids[] = { "PNP0C09", NULL };
347 
348     ret = ENXIO;
349 
350     /* Check that this is a device and that EC is not disabled. */
351     if (acpi_get_type(dev) != ACPI_TYPE_DEVICE || acpi_disabled("ec"))
352 	return (ret);
353 
354     if (device_is_devclass_fixed(dev)) {
355 	/*
356 	 * If probed via ECDT, set description and continue. Otherwise, we can
357 	 * access the namespace and make sure this is not a duplicate probe.
358 	 */
359         ecdt = 1;
360         params = acpi_get_private(dev);
361 	if (params != NULL)
362 	    ret = 0;
363 
364 	goto out;
365     } else
366 	ecdt = 0;
367 
368     rc = ACPI_ID_PROBE(device_get_parent(dev), dev, ec_ids, NULL);
369     if (rc > 0)
370 	return (rc);
371 
372     params = malloc(sizeof(struct acpi_ec_params), M_TEMP, M_WAITOK | M_ZERO);
373 
374     buf.Pointer = NULL;
375     buf.Length = ACPI_ALLOCATE_BUFFER;
376     h = acpi_get_handle(dev);
377 
378     /*
379      * Read the unit ID to check for duplicate attach and the global lock value
380      * to see if we should acquire it when accessing the EC.
381      */
382     status = acpi_GetInteger(h, "_UID", &params->uid);
383     if (ACPI_FAILURE(status))
384 	params->uid = 0;
385 
386     /*
387      * Check for a duplicate probe. This can happen when a probe via ECDT
388      * succeeded already. If this is a duplicate, disable this device.
389      *
390      * NB: It would seem device_disable would be sufficient to not get
391      * duplicated devices, and ENXIO isn't needed, however, device_probe() only
392      * checks DF_ENABLED at the start and so disabling it here is too late to
393      * prevent device_attach() from being called.
394      */
395     peer = devclass_get_device(device_get_devclass(dev), params->uid);
396     if (peer != NULL && device_is_alive(peer)) {
397 	device_disable(dev);
398 	goto out;
399     }
400 
401     status = acpi_GetInteger(h, "_GLK", &params->glk);
402     if (ACPI_FAILURE(status))
403 	params->glk = 0;
404 
405     /*
406      * Evaluate the _GPE method to find the GPE bit used by the EC to signal
407      * status (SCI).  If it's a package, it contains a reference and GPE bit,
408      * similar to _PRW.
409      */
410     status = AcpiEvaluateObject(h, "_GPE", NULL, &buf);
411     if (ACPI_FAILURE(status)) {
412 	device_printf(dev, "can't evaluate _GPE - %s\n", AcpiFormatException(status));
413 	goto out;
414     }
415 
416     obj = (ACPI_OBJECT *)buf.Pointer;
417     if (obj == NULL)
418 	goto out;
419 
420     switch (obj->Type) {
421     case ACPI_TYPE_INTEGER:
422 	params->gpe_handle = NULL;
423 	params->gpe_bit = obj->Integer.Value;
424 	break;
425     case ACPI_TYPE_PACKAGE:
426 	if (!ACPI_PKG_VALID(obj, 2))
427 	    goto out;
428 	params->gpe_handle = acpi_GetReference(NULL, &obj->Package.Elements[0]);
429 	if (params->gpe_handle == NULL ||
430 	    acpi_PkgInt32(obj, 1, &params->gpe_bit) != 0)
431 		goto out;
432 	break;
433     default:
434 	device_printf(dev, "_GPE has invalid type %d\n", obj->Type);
435 	goto out;
436     }
437 
438     /* Store the values we got from the namespace for attach. */
439     acpi_set_private(dev, params);
440 
441     if (buf.Pointer)
442 	AcpiOsFree(buf.Pointer);
443 
444     ret = rc;
445 out:
446     if (ret <= 0) {
447 	snprintf(desc, sizeof(desc), "Embedded Controller: GPE %#x%s%s",
448 		 params->gpe_bit, (params->glk) ? ", GLK" : "",
449 		 ecdt ? ", ECDT" : "");
450 	device_set_desc_copy(dev, desc);
451     } else
452 	free(params, M_TEMP);
453 
454     return (ret);
455 }
456 
457 static int
458 acpi_ec_attach(device_t dev)
459 {
460     struct acpi_ec_softc	*sc;
461     struct acpi_ec_params	*params;
462     ACPI_STATUS			Status;
463 
464     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
465 
466     /* Fetch/initialize softc (assumes softc is pre-zeroed). */
467     sc = device_get_softc(dev);
468     params = acpi_get_private(dev);
469     sc->ec_dev = dev;
470     sc->ec_handle = acpi_get_handle(dev);
471 
472     /* Retrieve previously probed values via device ivars. */
473     sc->ec_glk = params->glk;
474     sc->ec_gpebit = params->gpe_bit;
475     sc->ec_gpehandle = params->gpe_handle;
476     sc->ec_uid = params->uid;
477     sc->ec_suspending = FALSE;
478     acpi_set_private(dev, NULL);
479     free(params, M_TEMP);
480 
481     /* Attach bus resources for data and command/status ports. */
482     sc->ec_data_rid = 0;
483     sc->ec_data_res = bus_alloc_resource_any(sc->ec_dev, SYS_RES_IOPORT,
484 			&sc->ec_data_rid, RF_ACTIVE);
485     if (sc->ec_data_res == NULL) {
486 	device_printf(dev, "can't allocate data port\n");
487 	goto error;
488     }
489     sc->ec_data_tag = rman_get_bustag(sc->ec_data_res);
490     sc->ec_data_handle = rman_get_bushandle(sc->ec_data_res);
491 
492     sc->ec_csr_rid = 1;
493     sc->ec_csr_res = bus_alloc_resource_any(sc->ec_dev, SYS_RES_IOPORT,
494 			&sc->ec_csr_rid, RF_ACTIVE);
495     if (sc->ec_csr_res == NULL) {
496 	device_printf(dev, "can't allocate command/status port\n");
497 	goto error;
498     }
499     sc->ec_csr_tag = rman_get_bustag(sc->ec_csr_res);
500     sc->ec_csr_handle = rman_get_bushandle(sc->ec_csr_res);
501 
502     /*
503      * Install a handler for this EC's GPE bit.  We want edge-triggered
504      * behavior.
505      */
506     ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "attaching GPE handler\n"));
507     Status = AcpiInstallGpeHandler(sc->ec_gpehandle, sc->ec_gpebit,
508 		ACPI_GPE_EDGE_TRIGGERED, EcGpeHandler, sc);
509     if (ACPI_FAILURE(Status)) {
510 	device_printf(dev, "can't install GPE handler for %s - %s\n",
511 		      acpi_name(sc->ec_handle), AcpiFormatException(Status));
512 	goto error;
513     }
514 
515     /*
516      * Install address space handler
517      */
518     ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "attaching address space handler\n"));
519     Status = AcpiInstallAddressSpaceHandler(sc->ec_handle, ACPI_ADR_SPACE_EC,
520 		&EcSpaceHandler, &EcSpaceSetup, sc);
521     if (ACPI_FAILURE(Status)) {
522 	device_printf(dev, "can't install address space handler for %s - %s\n",
523 		      acpi_name(sc->ec_handle), AcpiFormatException(Status));
524 	goto error;
525     }
526 
527     /* Enable runtime GPEs for the handler. */
528     Status = AcpiEnableGpe(sc->ec_gpehandle, sc->ec_gpebit);
529     if (ACPI_FAILURE(Status)) {
530 	device_printf(dev, "AcpiEnableGpe failed: %s\n",
531 		      AcpiFormatException(Status));
532 	goto error;
533     }
534 
535     ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "acpi_ec_attach complete\n"));
536     return (0);
537 
538 error:
539     AcpiRemoveGpeHandler(sc->ec_gpehandle, sc->ec_gpebit, EcGpeHandler);
540     AcpiRemoveAddressSpaceHandler(sc->ec_handle, ACPI_ADR_SPACE_EC,
541 	EcSpaceHandler);
542     if (sc->ec_csr_res)
543 	bus_release_resource(sc->ec_dev, SYS_RES_IOPORT, sc->ec_csr_rid,
544 			     sc->ec_csr_res);
545     if (sc->ec_data_res)
546 	bus_release_resource(sc->ec_dev, SYS_RES_IOPORT, sc->ec_data_rid,
547 			     sc->ec_data_res);
548     return (ENXIO);
549 }
550 
551 static int
552 acpi_ec_suspend(device_t dev)
553 {
554     struct acpi_ec_softc	*sc;
555 
556     sc = device_get_softc(dev);
557     sc->ec_suspending = TRUE;
558     return (0);
559 }
560 
561 static int
562 acpi_ec_resume(device_t dev)
563 {
564     struct acpi_ec_softc	*sc;
565 
566     sc = device_get_softc(dev);
567     sc->ec_suspending = FALSE;
568     return (0);
569 }
570 
571 static int
572 acpi_ec_shutdown(device_t dev)
573 {
574     struct acpi_ec_softc	*sc;
575 
576     /* Disable the GPE so we don't get EC events during shutdown. */
577     sc = device_get_softc(dev);
578     AcpiDisableGpe(sc->ec_gpehandle, sc->ec_gpebit);
579     return (0);
580 }
581 
582 /* Methods to allow other devices (e.g., smbat) to read/write EC space. */
583 static int
584 acpi_ec_read_method(device_t dev, u_int addr, UINT64 *val, int width)
585 {
586     struct acpi_ec_softc *sc;
587     ACPI_STATUS status;
588 
589     sc = device_get_softc(dev);
590     status = EcSpaceHandler(ACPI_READ, addr, width * 8, val, sc, NULL);
591     if (ACPI_FAILURE(status))
592 	return (ENXIO);
593     return (0);
594 }
595 
596 static int
597 acpi_ec_write_method(device_t dev, u_int addr, UINT64 val, int width)
598 {
599     struct acpi_ec_softc *sc;
600     ACPI_STATUS status;
601 
602     sc = device_get_softc(dev);
603     status = EcSpaceHandler(ACPI_WRITE, addr, width * 8, &val, sc, NULL);
604     if (ACPI_FAILURE(status))
605 	return (ENXIO);
606     return (0);
607 }
608 
609 static ACPI_STATUS
610 EcCheckStatus(struct acpi_ec_softc *sc, const char *msg, EC_EVENT event)
611 {
612     ACPI_STATUS status;
613     EC_STATUS ec_status;
614 
615     status = AE_NO_HARDWARE_RESPONSE;
616     ec_status = EC_GET_CSR(sc);
617     if (sc->ec_burstactive && !(ec_status & EC_FLAG_BURST_MODE)) {
618 	CTR1(KTR_ACPI, "ec burst disabled in waitevent (%s)", msg);
619 	sc->ec_burstactive = FALSE;
620     }
621     if (EVENT_READY(event, ec_status)) {
622 	CTR2(KTR_ACPI, "ec %s wait ready, status %#x", msg, ec_status);
623 	status = AE_OK;
624     }
625     return (status);
626 }
627 
628 static void
629 EcGpeQueryHandlerSub(struct acpi_ec_softc *sc)
630 {
631     UINT8			Data;
632     ACPI_STATUS			Status;
633     int				retry;
634     char			qxx[5];
635 
636     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
637 
638     /* Serialize user access with EcSpaceHandler(). */
639     Status = EcLock(sc);
640     if (ACPI_FAILURE(Status)) {
641 	device_printf(sc->ec_dev, "GpeQuery lock error: %s\n",
642 	    AcpiFormatException(Status));
643 	return;
644     }
645 
646     /*
647      * Send a query command to the EC to find out which _Qxx call it
648      * wants to make.  This command clears the SCI bit and also the
649      * interrupt source since we are edge-triggered.  To prevent the GPE
650      * that may arise from running the query from causing another query
651      * to be queued, we clear the pending flag only after running it.
652      */
653     for (retry = 0; retry < 2; retry++) {
654 	Status = EcCommand(sc, EC_COMMAND_QUERY);
655 	if (ACPI_SUCCESS(Status))
656 	    break;
657 	if (ACPI_FAILURE(EcCheckStatus(sc, "retr_check",
658 	    EC_EVENT_INPUT_BUFFER_EMPTY)))
659 	    break;
660     }
661     if (ACPI_FAILURE(Status)) {
662 	EcUnlock(sc);
663 	device_printf(sc->ec_dev, "GPE query failed: %s\n",
664 	    AcpiFormatException(Status));
665 	return;
666     }
667     Data = EC_GET_DATA(sc);
668 
669     /*
670      * We have to unlock before running the _Qxx method below since that
671      * method may attempt to read/write from EC address space, causing
672      * recursive acquisition of the lock.
673      */
674     EcUnlock(sc);
675 
676     /* Ignore the value for "no outstanding event". (13.3.5) */
677     CTR2(KTR_ACPI, "ec query ok,%s running _Q%02X", Data ? "" : " not", Data);
678     if (Data == 0)
679 	return;
680 
681     /* Evaluate _Qxx to respond to the controller. */
682     snprintf(qxx, sizeof(qxx), "_Q%02X", Data);
683     AcpiUtStrupr(qxx);
684     Status = AcpiEvaluateObject(sc->ec_handle, qxx, NULL, NULL);
685     if (ACPI_FAILURE(Status) && Status != AE_NOT_FOUND) {
686 	device_printf(sc->ec_dev, "evaluation of query method %s failed: %s\n",
687 	    qxx, AcpiFormatException(Status));
688     }
689 }
690 
691 static void
692 EcGpeQueryHandler(void *Context)
693 {
694     struct acpi_ec_softc *sc = (struct acpi_ec_softc *)Context;
695     int pending;
696 
697     KASSERT(Context != NULL, ("EcGpeQueryHandler called with NULL"));
698 
699     do {
700 	/* Read the current pending count */
701 	pending = atomic_load_acq_int(&sc->ec_sci_pend);
702 
703 	/* Call GPE handler function */
704 	EcGpeQueryHandlerSub(sc);
705 
706 	/*
707 	 * Try to reset the pending count to zero. If this fails we
708 	 * know another GPE event has occurred while handling the
709 	 * current GPE event and need to loop.
710 	 */
711     } while (!atomic_cmpset_int(&sc->ec_sci_pend, pending, 0));
712 }
713 
714 /*
715  * The GPE handler is called when IBE/OBF or SCI events occur.  We are
716  * called from an unknown lock context.
717  */
718 static UINT32
719 EcGpeHandler(ACPI_HANDLE GpeDevice, UINT32 GpeNumber, void *Context)
720 {
721     struct acpi_ec_softc *sc = Context;
722     ACPI_STATUS		       Status;
723     EC_STATUS		       EcStatus;
724 
725     KASSERT(Context != NULL, ("EcGpeHandler called with NULL"));
726     CTR0(KTR_ACPI, "ec gpe handler start");
727 
728     /*
729      * Notify EcWaitEvent() that the status register is now fresh.  If we
730      * didn't do this, it wouldn't be possible to distinguish an old IBE
731      * from a new one, for example when doing a write transaction (writing
732      * address and then data values.)
733      */
734     atomic_add_int(&sc->ec_gencount, 1);
735     wakeup(sc);
736 
737     /*
738      * If the EC_SCI bit of the status register is set, queue a query handler.
739      * It will run the query and _Qxx method later, under the lock.
740      */
741     EcStatus = EC_GET_CSR(sc);
742     if ((EcStatus & EC_EVENT_SCI) &&
743 	atomic_fetchadd_int(&sc->ec_sci_pend, 1) == 0) {
744 	CTR0(KTR_ACPI, "ec gpe queueing query handler");
745 	Status = AcpiOsExecute(OSL_GPE_HANDLER, EcGpeQueryHandler, Context);
746 	if (ACPI_FAILURE(Status)) {
747 	    printf("EcGpeHandler: queuing GPE query handler failed\n");
748 	    atomic_store_rel_int(&sc->ec_sci_pend, 0);
749 	}
750     }
751     return (ACPI_REENABLE_GPE);
752 }
753 
754 static ACPI_STATUS
755 EcSpaceSetup(ACPI_HANDLE Region, UINT32 Function, void *Context,
756 	     void **RegionContext)
757 {
758 
759     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
760 
761     /*
762      * If deactivating a region, always set the output to NULL.  Otherwise,
763      * just pass the context through.
764      */
765     if (Function == ACPI_REGION_DEACTIVATE)
766 	*RegionContext = NULL;
767     else
768 	*RegionContext = Context;
769 
770     return_ACPI_STATUS (AE_OK);
771 }
772 
773 static ACPI_STATUS
774 EcSpaceHandler(UINT32 Function, ACPI_PHYSICAL_ADDRESS Address, UINT32 Width,
775 	       UINT64 *Value, void *Context, void *RegionContext)
776 {
777     struct acpi_ec_softc	*sc = (struct acpi_ec_softc *)Context;
778     ACPI_PHYSICAL_ADDRESS	EcAddr;
779     UINT8			*EcData;
780     ACPI_STATUS			Status;
781 
782     ACPI_FUNCTION_TRACE_U32((char *)(uintptr_t)__func__, (UINT32)Address);
783 
784     if (Function != ACPI_READ && Function != ACPI_WRITE)
785 	return_ACPI_STATUS (AE_BAD_PARAMETER);
786     if (Width % 8 != 0 || Value == NULL || Context == NULL)
787 	return_ACPI_STATUS (AE_BAD_PARAMETER);
788     if (Address + Width / 8 > 256)
789 	return_ACPI_STATUS (AE_BAD_ADDRESS);
790 
791     /*
792      * If booting, check if we need to run the query handler.  If so, we
793      * we call it directly here since our thread taskq is not active yet.
794      */
795     if (cold || rebooting || sc->ec_suspending) {
796 	if ((EC_GET_CSR(sc) & EC_EVENT_SCI) &&
797 	    atomic_fetchadd_int(&sc->ec_sci_pend, 1) == 0) {
798 	    CTR0(KTR_ACPI, "ec running gpe handler directly");
799 	    EcGpeQueryHandler(sc);
800 	}
801     }
802 
803     /* Serialize with EcGpeQueryHandler() at transaction granularity. */
804     Status = EcLock(sc);
805     if (ACPI_FAILURE(Status))
806 	return_ACPI_STATUS (Status);
807 
808     /* If we can't start burst mode, continue anyway. */
809     Status = EcCommand(sc, EC_COMMAND_BURST_ENABLE);
810     if (ACPI_SUCCESS(Status)) {
811 	if (EC_GET_DATA(sc) == EC_BURST_ACK) {
812 	    CTR0(KTR_ACPI, "ec burst enabled");
813 	    sc->ec_burstactive = TRUE;
814 	}
815     }
816 
817     /* Perform the transaction(s), based on Width. */
818     EcAddr = Address;
819     EcData = (UINT8 *)Value;
820     if (Function == ACPI_READ)
821 	*Value = 0;
822     do {
823 	switch (Function) {
824 	case ACPI_READ:
825 	    Status = EcRead(sc, EcAddr, EcData);
826 	    break;
827 	case ACPI_WRITE:
828 	    Status = EcWrite(sc, EcAddr, *EcData);
829 	    break;
830 	}
831 	if (ACPI_FAILURE(Status))
832 	    break;
833 	EcAddr++;
834 	EcData++;
835     } while (EcAddr < Address + Width / 8);
836 
837     if (sc->ec_burstactive) {
838 	sc->ec_burstactive = FALSE;
839 	if (ACPI_SUCCESS(EcCommand(sc, EC_COMMAND_BURST_DISABLE)))
840 	    CTR0(KTR_ACPI, "ec disabled burst ok");
841     }
842 
843     EcUnlock(sc);
844     return_ACPI_STATUS (Status);
845 }
846 
847 static ACPI_STATUS
848 EcWaitEvent(struct acpi_ec_softc *sc, EC_EVENT Event, u_int gen_count)
849 {
850     static int	no_intr = 0;
851     ACPI_STATUS	Status;
852     int		count, i, need_poll, slp_ival;
853 
854     ACPI_SERIAL_ASSERT(ec);
855     Status = AE_NO_HARDWARE_RESPONSE;
856     need_poll = cold || rebooting || ec_polled_mode || sc->ec_suspending;
857 
858     /* Wait for event by polling or GPE (interrupt). */
859     if (need_poll) {
860 	count = (ec_timeout * 1000) / EC_POLL_DELAY;
861 	if (count == 0)
862 	    count = 1;
863 	DELAY(10);
864 	for (i = 0; i < count; i++) {
865 	    Status = EcCheckStatus(sc, "poll", Event);
866 	    if (ACPI_SUCCESS(Status))
867 		break;
868 	    DELAY(EC_POLL_DELAY);
869 	}
870     } else {
871 	slp_ival = hz / 1000;
872 	if (slp_ival != 0) {
873 	    count = ec_timeout;
874 	} else {
875 	    /* hz has less than 1 ms resolution so scale timeout. */
876 	    slp_ival = 1;
877 	    count = ec_timeout / (1000 / hz);
878 	}
879 
880 	/*
881 	 * Wait for the GPE to signal the status changed, checking the
882 	 * status register each time we get one.  It's possible to get a
883 	 * GPE for an event we're not interested in here (i.e., SCI for
884 	 * EC query).
885 	 */
886 	for (i = 0; i < count; i++) {
887 	    if (gen_count == sc->ec_gencount)
888 		tsleep(sc, 0, "ecgpe", slp_ival);
889 	    /*
890 	     * Record new generation count.  It's possible the GPE was
891 	     * just to notify us that a query is needed and we need to
892 	     * wait for a second GPE to signal the completion of the
893 	     * event we are actually waiting for.
894 	     */
895 	    Status = EcCheckStatus(sc, "sleep", Event);
896 	    if (ACPI_SUCCESS(Status)) {
897 		if (gen_count == sc->ec_gencount)
898 		    no_intr++;
899 		else
900 		    no_intr = 0;
901 		break;
902 	    }
903 	    gen_count = sc->ec_gencount;
904 	}
905 
906 	/*
907 	 * We finished waiting for the GPE and it never arrived.  Try to
908 	 * read the register once and trust whatever value we got.  This is
909 	 * the best we can do at this point.
910 	 */
911 	if (ACPI_FAILURE(Status))
912 	    Status = EcCheckStatus(sc, "sleep_end", Event);
913     }
914     if (!need_poll && no_intr > 10) {
915 	device_printf(sc->ec_dev,
916 	    "not getting interrupts, switched to polled mode\n");
917 	ec_polled_mode = 1;
918     }
919     if (ACPI_FAILURE(Status))
920 	    CTR0(KTR_ACPI, "error: ec wait timed out");
921     return (Status);
922 }
923 
924 static ACPI_STATUS
925 EcCommand(struct acpi_ec_softc *sc, EC_COMMAND cmd)
926 {
927     ACPI_STATUS	status;
928     EC_EVENT	event;
929     EC_STATUS	ec_status;
930     u_int	gen_count;
931 
932     ACPI_SERIAL_ASSERT(ec);
933 
934     /* Don't use burst mode if user disabled it. */
935     if (!ec_burst_mode && cmd == EC_COMMAND_BURST_ENABLE)
936 	return (AE_ERROR);
937 
938     /* Decide what to wait for based on command type. */
939     switch (cmd) {
940     case EC_COMMAND_READ:
941     case EC_COMMAND_WRITE:
942     case EC_COMMAND_BURST_DISABLE:
943 	event = EC_EVENT_INPUT_BUFFER_EMPTY;
944 	break;
945     case EC_COMMAND_QUERY:
946     case EC_COMMAND_BURST_ENABLE:
947 	event = EC_EVENT_OUTPUT_BUFFER_FULL;
948 	break;
949     default:
950 	device_printf(sc->ec_dev, "EcCommand: invalid command %#x\n", cmd);
951 	return (AE_BAD_PARAMETER);
952     }
953 
954     /*
955      * Ensure empty input buffer before issuing command.
956      * Use generation count of zero to force a quick check.
957      */
958     status = EcWaitEvent(sc, EC_EVENT_INPUT_BUFFER_EMPTY, 0);
959     if (ACPI_FAILURE(status))
960 	return (status);
961 
962     /* Run the command and wait for the chosen event. */
963     CTR1(KTR_ACPI, "ec running command %#x", cmd);
964     gen_count = sc->ec_gencount;
965     EC_SET_CSR(sc, cmd);
966     status = EcWaitEvent(sc, event, gen_count);
967     if (ACPI_SUCCESS(status)) {
968 	/* If we succeeded, burst flag should now be present. */
969 	if (cmd == EC_COMMAND_BURST_ENABLE) {
970 	    ec_status = EC_GET_CSR(sc);
971 	    if ((ec_status & EC_FLAG_BURST_MODE) == 0)
972 		status = AE_ERROR;
973 	}
974     } else
975 	device_printf(sc->ec_dev, "EcCommand: no response to %#x\n", cmd);
976     return (status);
977 }
978 
979 static ACPI_STATUS
980 EcRead(struct acpi_ec_softc *sc, UINT8 Address, UINT8 *Data)
981 {
982     ACPI_STATUS	status;
983     u_int gen_count;
984     int retry;
985 
986     ACPI_SERIAL_ASSERT(ec);
987     CTR1(KTR_ACPI, "ec read from %#x", Address);
988 
989     for (retry = 0; retry < 2; retry++) {
990 	status = EcCommand(sc, EC_COMMAND_READ);
991 	if (ACPI_FAILURE(status))
992 	    return (status);
993 
994 	gen_count = sc->ec_gencount;
995 	EC_SET_DATA(sc, Address);
996 	status = EcWaitEvent(sc, EC_EVENT_OUTPUT_BUFFER_FULL, gen_count);
997 	if (ACPI_SUCCESS(status)) {
998 	    *Data = EC_GET_DATA(sc);
999 	    return (AE_OK);
1000 	}
1001 	if (ACPI_FAILURE(EcCheckStatus(sc, "retr_check",
1002 	    EC_EVENT_INPUT_BUFFER_EMPTY)))
1003 	    break;
1004     }
1005     device_printf(sc->ec_dev, "EcRead: failed waiting to get data\n");
1006     return (status);
1007 }
1008 
1009 static ACPI_STATUS
1010 EcWrite(struct acpi_ec_softc *sc, UINT8 Address, UINT8 Data)
1011 {
1012     ACPI_STATUS	status;
1013     u_int gen_count;
1014 
1015     ACPI_SERIAL_ASSERT(ec);
1016     CTR2(KTR_ACPI, "ec write to %#x, data %#x", Address, Data);
1017 
1018     status = EcCommand(sc, EC_COMMAND_WRITE);
1019     if (ACPI_FAILURE(status))
1020 	return (status);
1021 
1022     gen_count = sc->ec_gencount;
1023     EC_SET_DATA(sc, Address);
1024     status = EcWaitEvent(sc, EC_EVENT_INPUT_BUFFER_EMPTY, gen_count);
1025     if (ACPI_FAILURE(status)) {
1026 	device_printf(sc->ec_dev, "EcWrite: failed waiting for sent address\n");
1027 	return (status);
1028     }
1029 
1030     gen_count = sc->ec_gencount;
1031     EC_SET_DATA(sc, Data);
1032     status = EcWaitEvent(sc, EC_EVENT_INPUT_BUFFER_EMPTY, gen_count);
1033     if (ACPI_FAILURE(status)) {
1034 	device_printf(sc->ec_dev, "EcWrite: failed waiting for sent data\n");
1035 	return (status);
1036     }
1037 
1038     return (AE_OK);
1039 }
1040