xref: /freebsd/sys/dev/acpica/acpi_ec.c (revision 1f474190)
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 __FBSDID("$FreeBSD$");
31 
32 #include "opt_acpi.h"
33 #include <sys/param.h>
34 #include <sys/kernel.h>
35 #include <sys/ktr.h>
36 #include <sys/bus.h>
37 #include <sys/lock.h>
38 #include <sys/malloc.h>
39 #include <sys/module.h>
40 #include <sys/sx.h>
41 
42 #include <machine/bus.h>
43 #include <machine/resource.h>
44 #include <sys/rman.h>
45 
46 #include <contrib/dev/acpica/include/acpi.h>
47 #include <contrib/dev/acpica/include/accommon.h>
48 
49 #include <dev/acpica/acpivar.h>
50 
51 /* Hooks for the ACPI CA debugging infrastructure */
52 #define _COMPONENT	ACPI_EC
53 ACPI_MODULE_NAME("EC")
54 
55 /*
56  * EC_COMMAND:
57  * -----------
58  */
59 typedef UINT8				EC_COMMAND;
60 
61 #define EC_COMMAND_UNKNOWN		((EC_COMMAND) 0x00)
62 #define EC_COMMAND_READ			((EC_COMMAND) 0x80)
63 #define EC_COMMAND_WRITE		((EC_COMMAND) 0x81)
64 #define EC_COMMAND_BURST_ENABLE		((EC_COMMAND) 0x82)
65 #define EC_COMMAND_BURST_DISABLE	((EC_COMMAND) 0x83)
66 #define EC_COMMAND_QUERY		((EC_COMMAND) 0x84)
67 
68 /*
69  * EC_STATUS:
70  * ----------
71  * The encoding of the EC status register is illustrated below.
72  * Note that a set bit (1) indicates the property is TRUE
73  * (e.g. if bit 0 is set then the output buffer is full).
74  * +-+-+-+-+-+-+-+-+
75  * |7|6|5|4|3|2|1|0|
76  * +-+-+-+-+-+-+-+-+
77  *  | | | | | | | |
78  *  | | | | | | | +- Output Buffer Full?
79  *  | | | | | | +--- Input Buffer Full?
80  *  | | | | | +----- <reserved>
81  *  | | | | +------- Data Register is Command Byte?
82  *  | | | +--------- Burst Mode Enabled?
83  *  | | +----------- SCI Event?
84  *  | +------------- SMI Event?
85  *  +--------------- <reserved>
86  *
87  */
88 typedef UINT8				EC_STATUS;
89 
90 #define EC_FLAG_OUTPUT_BUFFER		((EC_STATUS) 0x01)
91 #define EC_FLAG_INPUT_BUFFER		((EC_STATUS) 0x02)
92 #define EC_FLAG_DATA_IS_CMD		((EC_STATUS) 0x08)
93 #define EC_FLAG_BURST_MODE		((EC_STATUS) 0x10)
94 
95 /*
96  * EC_EVENT:
97  * ---------
98  */
99 typedef UINT8				EC_EVENT;
100 
101 #define EC_EVENT_UNKNOWN		((EC_EVENT) 0x00)
102 #define EC_EVENT_OUTPUT_BUFFER_FULL	((EC_EVENT) 0x01)
103 #define EC_EVENT_INPUT_BUFFER_EMPTY	((EC_EVENT) 0x02)
104 #define EC_EVENT_SCI			((EC_EVENT) 0x20)
105 #define EC_EVENT_SMI			((EC_EVENT) 0x40)
106 
107 /* Data byte returned after burst enable indicating it was successful. */
108 #define EC_BURST_ACK			0x90
109 
110 /*
111  * Register access primitives
112  */
113 #define EC_GET_DATA(sc)							\
114 	bus_space_read_1((sc)->ec_data_tag, (sc)->ec_data_handle, 0)
115 
116 #define EC_SET_DATA(sc, v)						\
117 	bus_space_write_1((sc)->ec_data_tag, (sc)->ec_data_handle, 0, (v))
118 
119 #define EC_GET_CSR(sc)							\
120 	bus_space_read_1((sc)->ec_csr_tag, (sc)->ec_csr_handle, 0)
121 
122 #define EC_SET_CSR(sc, v)						\
123 	bus_space_write_1((sc)->ec_csr_tag, (sc)->ec_csr_handle, 0, (v))
124 
125 /* Additional params to pass from the probe routine */
126 struct acpi_ec_params {
127     int		glk;
128     int		gpe_bit;
129     ACPI_HANDLE	gpe_handle;
130     int		uid;
131 };
132 
133 /*
134  * Driver softc.
135  */
136 struct acpi_ec_softc {
137     device_t		ec_dev;
138     ACPI_HANDLE		ec_handle;
139     int			ec_uid;
140     ACPI_HANDLE		ec_gpehandle;
141     UINT8		ec_gpebit;
142 
143     int			ec_data_rid;
144     struct resource	*ec_data_res;
145     bus_space_tag_t	ec_data_tag;
146     bus_space_handle_t	ec_data_handle;
147 
148     int			ec_csr_rid;
149     struct resource	*ec_csr_res;
150     bus_space_tag_t	ec_csr_tag;
151     bus_space_handle_t	ec_csr_handle;
152 
153     int			ec_glk;
154     int			ec_glkhandle;
155     int			ec_burstactive;
156     int			ec_sci_pend;
157     volatile u_int	ec_gencount;
158     int			ec_suspending;
159 };
160 
161 /*
162  * XXX njl
163  * I couldn't find it in the spec but other implementations also use a
164  * value of 1 ms for the time to acquire global lock.
165  */
166 #define EC_LOCK_TIMEOUT	1000
167 
168 /* Default delay in microseconds between each run of the status polling loop. */
169 #define EC_POLL_DELAY	50
170 
171 /* Total time in ms spent waiting for a response from EC. */
172 #define EC_TIMEOUT	750
173 
174 #define EVENT_READY(event, status)			\
175 	(((event) == EC_EVENT_OUTPUT_BUFFER_FULL &&	\
176 	 ((status) & EC_FLAG_OUTPUT_BUFFER) != 0) ||	\
177 	 ((event) == EC_EVENT_INPUT_BUFFER_EMPTY && 	\
178 	 ((status) & EC_FLAG_INPUT_BUFFER) == 0))
179 
180 ACPI_SERIAL_DECL(ec, "ACPI embedded controller");
181 
182 static SYSCTL_NODE(_debug_acpi, OID_AUTO, ec,
183     CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
184     "EC debugging");
185 
186 static int	ec_burst_mode;
187 SYSCTL_INT(_debug_acpi_ec, OID_AUTO, burst, CTLFLAG_RWTUN, &ec_burst_mode, 0,
188     "Enable use of burst mode (faster for nearly all systems)");
189 static int	ec_polled_mode;
190 SYSCTL_INT(_debug_acpi_ec, OID_AUTO, polled, CTLFLAG_RWTUN, &ec_polled_mode, 0,
191     "Force use of polled mode (only if interrupt mode doesn't work)");
192 static int	ec_timeout = EC_TIMEOUT;
193 SYSCTL_INT(_debug_acpi_ec, OID_AUTO, timeout, CTLFLAG_RWTUN, &ec_timeout,
194     EC_TIMEOUT, "Total time spent waiting for a response (poll+sleep)");
195 
196 static ACPI_STATUS
197 EcLock(struct acpi_ec_softc *sc)
198 {
199     ACPI_STATUS	status;
200 
201     /* If _GLK is non-zero, acquire the global lock. */
202     status = AE_OK;
203     if (sc->ec_glk) {
204 	status = AcpiAcquireGlobalLock(EC_LOCK_TIMEOUT, &sc->ec_glkhandle);
205 	if (ACPI_FAILURE(status))
206 	    return (status);
207     }
208     ACPI_SERIAL_BEGIN(ec);
209     return (status);
210 }
211 
212 static void
213 EcUnlock(struct acpi_ec_softc *sc)
214 {
215     ACPI_SERIAL_END(ec);
216     if (sc->ec_glk)
217 	AcpiReleaseGlobalLock(sc->ec_glkhandle);
218 }
219 
220 static UINT32		EcGpeHandler(ACPI_HANDLE, UINT32, void *);
221 static ACPI_STATUS	EcSpaceSetup(ACPI_HANDLE Region, UINT32 Function,
222 				void *Context, void **return_Context);
223 static ACPI_STATUS	EcSpaceHandler(UINT32 Function,
224 				ACPI_PHYSICAL_ADDRESS Address,
225 				UINT32 Width, UINT64 *Value,
226 				void *Context, void *RegionContext);
227 static ACPI_STATUS	EcWaitEvent(struct acpi_ec_softc *sc, EC_EVENT Event,
228 				u_int gen_count);
229 static ACPI_STATUS	EcCommand(struct acpi_ec_softc *sc, EC_COMMAND cmd);
230 static ACPI_STATUS	EcRead(struct acpi_ec_softc *sc, UINT8 Address,
231 				UINT8 *Data);
232 static ACPI_STATUS	EcWrite(struct acpi_ec_softc *sc, UINT8 Address,
233 				UINT8 Data);
234 static int		acpi_ec_probe(device_t dev);
235 static int		acpi_ec_attach(device_t dev);
236 static int		acpi_ec_suspend(device_t dev);
237 static int		acpi_ec_resume(device_t dev);
238 static int		acpi_ec_shutdown(device_t dev);
239 static int		acpi_ec_read_method(device_t dev, u_int addr,
240 				UINT64 *val, int width);
241 static int		acpi_ec_write_method(device_t dev, u_int addr,
242 				UINT64 val, int width);
243 
244 static device_method_t acpi_ec_methods[] = {
245     /* Device interface */
246     DEVMETHOD(device_probe,	acpi_ec_probe),
247     DEVMETHOD(device_attach,	acpi_ec_attach),
248     DEVMETHOD(device_suspend,	acpi_ec_suspend),
249     DEVMETHOD(device_resume,	acpi_ec_resume),
250     DEVMETHOD(device_shutdown,	acpi_ec_shutdown),
251 
252     /* Embedded controller interface */
253     DEVMETHOD(acpi_ec_read,	acpi_ec_read_method),
254     DEVMETHOD(acpi_ec_write,	acpi_ec_write_method),
255 
256     DEVMETHOD_END
257 };
258 
259 static driver_t acpi_ec_driver = {
260     "acpi_ec",
261     acpi_ec_methods,
262     sizeof(struct acpi_ec_softc),
263 };
264 
265 static devclass_t acpi_ec_devclass;
266 DRIVER_MODULE(acpi_ec, acpi, acpi_ec_driver, acpi_ec_devclass, 0, 0);
267 MODULE_DEPEND(acpi_ec, acpi, 1, 1, 1);
268 
269 /*
270  * Look for an ECDT and if we find one, set up default GPE and
271  * space handlers to catch attempts to access EC space before
272  * we have a real driver instance in place.
273  *
274  * TODO: Some old Gateway laptops need us to fake up an ECDT or
275  * otherwise attach early so that _REG methods can run.
276  */
277 void
278 acpi_ec_ecdt_probe(device_t parent)
279 {
280     ACPI_TABLE_ECDT *ecdt;
281     ACPI_STATUS	     status;
282     device_t	     child;
283     ACPI_HANDLE	     h;
284     struct acpi_ec_params *params;
285 
286     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
287 
288     /* Find and validate the ECDT. */
289     status = AcpiGetTable(ACPI_SIG_ECDT, 1, (ACPI_TABLE_HEADER **)&ecdt);
290     if (ACPI_FAILURE(status) ||
291 	ecdt->Control.BitWidth != 8 ||
292 	ecdt->Data.BitWidth != 8) {
293 	return;
294     }
295 
296     /* Create the child device with the given unit number. */
297     child = BUS_ADD_CHILD(parent, 3, "acpi_ec", ecdt->Uid);
298     if (child == NULL) {
299 	printf("%s: can't add child\n", __func__);
300 	return;
301     }
302 
303     /* Find and save the ACPI handle for this device. */
304     status = AcpiGetHandle(NULL, ecdt->Id, &h);
305     if (ACPI_FAILURE(status)) {
306 	device_delete_child(parent, child);
307 	printf("%s: can't get handle\n", __func__);
308 	return;
309     }
310     acpi_set_handle(child, h);
311 
312     /* Set the data and CSR register addresses. */
313     bus_set_resource(child, SYS_RES_IOPORT, 0, ecdt->Data.Address,
314 	/*count*/1);
315     bus_set_resource(child, SYS_RES_IOPORT, 1, ecdt->Control.Address,
316 	/*count*/1);
317 
318     /*
319      * Store values for the probe/attach routines to use.  Store the
320      * ECDT GPE bit and set the global lock flag according to _GLK.
321      * Note that it is not perfectly correct to be evaluating a method
322      * before initializing devices, but in practice this function
323      * should be safe to call at this point.
324      */
325     params = malloc(sizeof(struct acpi_ec_params), M_TEMP, M_WAITOK | M_ZERO);
326     params->gpe_handle = NULL;
327     params->gpe_bit = ecdt->Gpe;
328     params->uid = ecdt->Uid;
329     acpi_GetInteger(h, "_GLK", &params->glk);
330     acpi_set_private(child, params);
331 
332     /* Finish the attach process. */
333     if (device_probe_and_attach(child) != 0)
334 	device_delete_child(parent, child);
335 }
336 
337 static int
338 acpi_ec_probe(device_t dev)
339 {
340     ACPI_BUFFER buf;
341     ACPI_HANDLE h;
342     ACPI_OBJECT *obj;
343     ACPI_STATUS status;
344     device_t	peer;
345     char	desc[64];
346     int		ecdt;
347     int		ret, rc;
348     struct acpi_ec_params *params;
349     static char *ec_ids[] = { "PNP0C09", NULL };
350 
351     ret = ENXIO;
352 
353     /* Check that this is a device and that EC is not disabled. */
354     if (acpi_get_type(dev) != ACPI_TYPE_DEVICE || acpi_disabled("ec"))
355 	return (ret);
356 
357     if (device_is_devclass_fixed(dev)) {
358 	/*
359 	 * If probed via ECDT, set description and continue. Otherwise, we can
360 	 * access the namespace and make sure this is not a duplicate probe.
361 	 */
362         ecdt = 1;
363         params = acpi_get_private(dev);
364 	if (params != NULL)
365 	    ret = 0;
366 
367 	goto out;
368     } else
369 	ecdt = 0;
370 
371     rc = ACPI_ID_PROBE(device_get_parent(dev), dev, ec_ids, NULL);
372     if (rc > 0)
373 	return (rc);
374 
375     params = malloc(sizeof(struct acpi_ec_params), M_TEMP, M_WAITOK | M_ZERO);
376 
377     buf.Pointer = NULL;
378     buf.Length = ACPI_ALLOCATE_BUFFER;
379     h = acpi_get_handle(dev);
380 
381     /*
382      * Read the unit ID to check for duplicate attach and the global lock value
383      * to see if we should acquire it when accessing the EC.
384      */
385     status = acpi_GetInteger(h, "_UID", &params->uid);
386     if (ACPI_FAILURE(status))
387 	params->uid = 0;
388 
389     /*
390      * Check for a duplicate probe. This can happen when a probe via ECDT
391      * succeeded already. If this is a duplicate, disable this device.
392      *
393      * NB: It would seem device_disable would be sufficient to not get
394      * duplicated devices, and ENXIO isn't needed, however, device_probe() only
395      * checks DF_ENABLED at the start and so disabling it here is too late to
396      * prevent device_attach() from being called.
397      */
398     peer = devclass_get_device(acpi_ec_devclass, params->uid);
399     if (peer != NULL && device_is_alive(peer)) {
400 	device_disable(dev);
401 	goto out;
402     }
403 
404     status = acpi_GetInteger(h, "_GLK", &params->glk);
405     if (ACPI_FAILURE(status))
406 	params->glk = 0;
407 
408     /*
409      * Evaluate the _GPE method to find the GPE bit used by the EC to signal
410      * status (SCI).  If it's a package, it contains a reference and GPE bit,
411      * similar to _PRW.
412      */
413     status = AcpiEvaluateObject(h, "_GPE", NULL, &buf);
414     if (ACPI_FAILURE(status)) {
415 	device_printf(dev, "can't evaluate _GPE - %s\n", AcpiFormatException(status));
416 	goto out;
417     }
418 
419     obj = (ACPI_OBJECT *)buf.Pointer;
420     if (obj == NULL)
421 	goto out;
422 
423     switch (obj->Type) {
424     case ACPI_TYPE_INTEGER:
425 	params->gpe_handle = NULL;
426 	params->gpe_bit = obj->Integer.Value;
427 	break;
428     case ACPI_TYPE_PACKAGE:
429 	if (!ACPI_PKG_VALID(obj, 2))
430 	    goto out;
431 	params->gpe_handle = acpi_GetReference(NULL, &obj->Package.Elements[0]);
432 	if (params->gpe_handle == NULL ||
433 	    acpi_PkgInt32(obj, 1, &params->gpe_bit) != 0)
434 		goto out;
435 	break;
436     default:
437 	device_printf(dev, "_GPE has invalid type %d\n", obj->Type);
438 	goto out;
439     }
440 
441     /* Store the values we got from the namespace for attach. */
442     acpi_set_private(dev, params);
443 
444     if (buf.Pointer)
445 	AcpiOsFree(buf.Pointer);
446 
447     ret = rc;
448 out:
449     if (ret <= 0) {
450 	snprintf(desc, sizeof(desc), "Embedded Controller: GPE %#x%s%s",
451 		 params->gpe_bit, (params->glk) ? ", GLK" : "",
452 		 ecdt ? ", ECDT" : "");
453 	device_set_desc_copy(dev, desc);
454     } else
455 	free(params, M_TEMP);
456 
457     return (ret);
458 }
459 
460 static int
461 acpi_ec_attach(device_t dev)
462 {
463     struct acpi_ec_softc	*sc;
464     struct acpi_ec_params	*params;
465     ACPI_STATUS			Status;
466 
467     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
468 
469     /* Fetch/initialize softc (assumes softc is pre-zeroed). */
470     sc = device_get_softc(dev);
471     params = acpi_get_private(dev);
472     sc->ec_dev = dev;
473     sc->ec_handle = acpi_get_handle(dev);
474 
475     /* Retrieve previously probed values via device ivars. */
476     sc->ec_glk = params->glk;
477     sc->ec_gpebit = params->gpe_bit;
478     sc->ec_gpehandle = params->gpe_handle;
479     sc->ec_uid = params->uid;
480     sc->ec_suspending = FALSE;
481     acpi_set_private(dev, NULL);
482     free(params, M_TEMP);
483 
484     /* Attach bus resources for data and command/status ports. */
485     sc->ec_data_rid = 0;
486     sc->ec_data_res = bus_alloc_resource_any(sc->ec_dev, SYS_RES_IOPORT,
487 			&sc->ec_data_rid, RF_ACTIVE);
488     if (sc->ec_data_res == NULL) {
489 	device_printf(dev, "can't allocate data port\n");
490 	goto error;
491     }
492     sc->ec_data_tag = rman_get_bustag(sc->ec_data_res);
493     sc->ec_data_handle = rman_get_bushandle(sc->ec_data_res);
494 
495     sc->ec_csr_rid = 1;
496     sc->ec_csr_res = bus_alloc_resource_any(sc->ec_dev, SYS_RES_IOPORT,
497 			&sc->ec_csr_rid, RF_ACTIVE);
498     if (sc->ec_csr_res == NULL) {
499 	device_printf(dev, "can't allocate command/status port\n");
500 	goto error;
501     }
502     sc->ec_csr_tag = rman_get_bustag(sc->ec_csr_res);
503     sc->ec_csr_handle = rman_get_bushandle(sc->ec_csr_res);
504 
505     /*
506      * Install a handler for this EC's GPE bit.  We want edge-triggered
507      * behavior.
508      */
509     ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "attaching GPE handler\n"));
510     Status = AcpiInstallGpeHandler(sc->ec_gpehandle, sc->ec_gpebit,
511 		ACPI_GPE_EDGE_TRIGGERED, EcGpeHandler, sc);
512     if (ACPI_FAILURE(Status)) {
513 	device_printf(dev, "can't install GPE handler for %s - %s\n",
514 		      acpi_name(sc->ec_handle), AcpiFormatException(Status));
515 	goto error;
516     }
517 
518     /*
519      * Install address space handler
520      */
521     ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "attaching address space handler\n"));
522     Status = AcpiInstallAddressSpaceHandler(sc->ec_handle, ACPI_ADR_SPACE_EC,
523 		&EcSpaceHandler, &EcSpaceSetup, sc);
524     if (ACPI_FAILURE(Status)) {
525 	device_printf(dev, "can't install address space handler for %s - %s\n",
526 		      acpi_name(sc->ec_handle), AcpiFormatException(Status));
527 	goto error;
528     }
529 
530     /* Enable runtime GPEs for the handler. */
531     Status = AcpiEnableGpe(sc->ec_gpehandle, sc->ec_gpebit);
532     if (ACPI_FAILURE(Status)) {
533 	device_printf(dev, "AcpiEnableGpe failed: %s\n",
534 		      AcpiFormatException(Status));
535 	goto error;
536     }
537 
538     ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "acpi_ec_attach complete\n"));
539     return (0);
540 
541 error:
542     AcpiRemoveGpeHandler(sc->ec_gpehandle, sc->ec_gpebit, EcGpeHandler);
543     AcpiRemoveAddressSpaceHandler(sc->ec_handle, ACPI_ADR_SPACE_EC,
544 	EcSpaceHandler);
545     if (sc->ec_csr_res)
546 	bus_release_resource(sc->ec_dev, SYS_RES_IOPORT, sc->ec_csr_rid,
547 			     sc->ec_csr_res);
548     if (sc->ec_data_res)
549 	bus_release_resource(sc->ec_dev, SYS_RES_IOPORT, sc->ec_data_rid,
550 			     sc->ec_data_res);
551     return (ENXIO);
552 }
553 
554 static int
555 acpi_ec_suspend(device_t dev)
556 {
557     struct acpi_ec_softc	*sc;
558 
559     sc = device_get_softc(dev);
560     sc->ec_suspending = TRUE;
561     return (0);
562 }
563 
564 static int
565 acpi_ec_resume(device_t dev)
566 {
567     struct acpi_ec_softc	*sc;
568 
569     sc = device_get_softc(dev);
570     sc->ec_suspending = FALSE;
571     return (0);
572 }
573 
574 static int
575 acpi_ec_shutdown(device_t dev)
576 {
577     struct acpi_ec_softc	*sc;
578 
579     /* Disable the GPE so we don't get EC events during shutdown. */
580     sc = device_get_softc(dev);
581     AcpiDisableGpe(sc->ec_gpehandle, sc->ec_gpebit);
582     return (0);
583 }
584 
585 /* Methods to allow other devices (e.g., smbat) to read/write EC space. */
586 static int
587 acpi_ec_read_method(device_t dev, u_int addr, UINT64 *val, int width)
588 {
589     struct acpi_ec_softc *sc;
590     ACPI_STATUS status;
591 
592     sc = device_get_softc(dev);
593     status = EcSpaceHandler(ACPI_READ, addr, width * 8, val, sc, NULL);
594     if (ACPI_FAILURE(status))
595 	return (ENXIO);
596     return (0);
597 }
598 
599 static int
600 acpi_ec_write_method(device_t dev, u_int addr, UINT64 val, int width)
601 {
602     struct acpi_ec_softc *sc;
603     ACPI_STATUS status;
604 
605     sc = device_get_softc(dev);
606     status = EcSpaceHandler(ACPI_WRITE, addr, width * 8, &val, sc, NULL);
607     if (ACPI_FAILURE(status))
608 	return (ENXIO);
609     return (0);
610 }
611 
612 static ACPI_STATUS
613 EcCheckStatus(struct acpi_ec_softc *sc, const char *msg, EC_EVENT event)
614 {
615     ACPI_STATUS status;
616     EC_STATUS ec_status;
617 
618     status = AE_NO_HARDWARE_RESPONSE;
619     ec_status = EC_GET_CSR(sc);
620     if (sc->ec_burstactive && !(ec_status & EC_FLAG_BURST_MODE)) {
621 	CTR1(KTR_ACPI, "ec burst disabled in waitevent (%s)", msg);
622 	sc->ec_burstactive = FALSE;
623     }
624     if (EVENT_READY(event, ec_status)) {
625 	CTR2(KTR_ACPI, "ec %s wait ready, status %#x", msg, ec_status);
626 	status = AE_OK;
627     }
628     return (status);
629 }
630 
631 static void
632 EcGpeQueryHandlerSub(struct acpi_ec_softc *sc)
633 {
634     UINT8			Data;
635     ACPI_STATUS			Status;
636     int				retry;
637     char			qxx[5];
638 
639     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
640 
641     /* Serialize user access with EcSpaceHandler(). */
642     Status = EcLock(sc);
643     if (ACPI_FAILURE(Status)) {
644 	device_printf(sc->ec_dev, "GpeQuery lock error: %s\n",
645 	    AcpiFormatException(Status));
646 	return;
647     }
648 
649     /*
650      * Send a query command to the EC to find out which _Qxx call it
651      * wants to make.  This command clears the SCI bit and also the
652      * interrupt source since we are edge-triggered.  To prevent the GPE
653      * that may arise from running the query from causing another query
654      * to be queued, we clear the pending flag only after running it.
655      */
656     for (retry = 0; retry < 2; retry++) {
657 	Status = EcCommand(sc, EC_COMMAND_QUERY);
658 	if (ACPI_SUCCESS(Status))
659 	    break;
660 	if (ACPI_FAILURE(EcCheckStatus(sc, "retr_check",
661 	    EC_EVENT_INPUT_BUFFER_EMPTY)))
662 	    break;
663     }
664     if (ACPI_FAILURE(Status)) {
665 	EcUnlock(sc);
666 	device_printf(sc->ec_dev, "GPE query failed: %s\n",
667 	    AcpiFormatException(Status));
668 	return;
669     }
670     Data = EC_GET_DATA(sc);
671 
672     /*
673      * We have to unlock before running the _Qxx method below since that
674      * method may attempt to read/write from EC address space, causing
675      * recursive acquisition of the lock.
676      */
677     EcUnlock(sc);
678 
679     /* Ignore the value for "no outstanding event". (13.3.5) */
680     CTR2(KTR_ACPI, "ec query ok,%s running _Q%02X", Data ? "" : " not", Data);
681     if (Data == 0)
682 	return;
683 
684     /* Evaluate _Qxx to respond to the controller. */
685     snprintf(qxx, sizeof(qxx), "_Q%02X", Data);
686     AcpiUtStrupr(qxx);
687     Status = AcpiEvaluateObject(sc->ec_handle, qxx, NULL, NULL);
688     if (ACPI_FAILURE(Status) && Status != AE_NOT_FOUND) {
689 	device_printf(sc->ec_dev, "evaluation of query method %s failed: %s\n",
690 	    qxx, AcpiFormatException(Status));
691     }
692 }
693 
694 static void
695 EcGpeQueryHandler(void *Context)
696 {
697     struct acpi_ec_softc *sc = (struct acpi_ec_softc *)Context;
698     int pending;
699 
700     KASSERT(Context != NULL, ("EcGpeQueryHandler called with NULL"));
701 
702     do {
703 	/* Read the current pending count */
704 	pending = atomic_load_acq_int(&sc->ec_sci_pend);
705 
706 	/* Call GPE handler function */
707 	EcGpeQueryHandlerSub(sc);
708 
709 	/*
710 	 * Try to reset the pending count to zero. If this fails we
711 	 * know another GPE event has occurred while handling the
712 	 * current GPE event and need to loop.
713 	 */
714     } while (!atomic_cmpset_int(&sc->ec_sci_pend, pending, 0));
715 }
716 
717 /*
718  * The GPE handler is called when IBE/OBF or SCI events occur.  We are
719  * called from an unknown lock context.
720  */
721 static UINT32
722 EcGpeHandler(ACPI_HANDLE GpeDevice, UINT32 GpeNumber, void *Context)
723 {
724     struct acpi_ec_softc *sc = Context;
725     ACPI_STATUS		       Status;
726     EC_STATUS		       EcStatus;
727 
728     KASSERT(Context != NULL, ("EcGpeHandler called with NULL"));
729     CTR0(KTR_ACPI, "ec gpe handler start");
730 
731     /*
732      * Notify EcWaitEvent() that the status register is now fresh.  If we
733      * didn't do this, it wouldn't be possible to distinguish an old IBE
734      * from a new one, for example when doing a write transaction (writing
735      * address and then data values.)
736      */
737     atomic_add_int(&sc->ec_gencount, 1);
738     wakeup(sc);
739 
740     /*
741      * If the EC_SCI bit of the status register is set, queue a query handler.
742      * It will run the query and _Qxx method later, under the lock.
743      */
744     EcStatus = EC_GET_CSR(sc);
745     if ((EcStatus & EC_EVENT_SCI) &&
746 	atomic_fetchadd_int(&sc->ec_sci_pend, 1) == 0) {
747 	CTR0(KTR_ACPI, "ec gpe queueing query handler");
748 	Status = AcpiOsExecute(OSL_GPE_HANDLER, EcGpeQueryHandler, Context);
749 	if (ACPI_FAILURE(Status)) {
750 	    printf("EcGpeHandler: queuing GPE query handler failed\n");
751 	    atomic_store_rel_int(&sc->ec_sci_pend, 0);
752 	}
753     }
754     return (ACPI_REENABLE_GPE);
755 }
756 
757 static ACPI_STATUS
758 EcSpaceSetup(ACPI_HANDLE Region, UINT32 Function, void *Context,
759 	     void **RegionContext)
760 {
761 
762     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
763 
764     /*
765      * If deactivating a region, always set the output to NULL.  Otherwise,
766      * just pass the context through.
767      */
768     if (Function == ACPI_REGION_DEACTIVATE)
769 	*RegionContext = NULL;
770     else
771 	*RegionContext = Context;
772 
773     return_ACPI_STATUS (AE_OK);
774 }
775 
776 static ACPI_STATUS
777 EcSpaceHandler(UINT32 Function, ACPI_PHYSICAL_ADDRESS Address, UINT32 Width,
778 	       UINT64 *Value, void *Context, void *RegionContext)
779 {
780     struct acpi_ec_softc	*sc = (struct acpi_ec_softc *)Context;
781     ACPI_PHYSICAL_ADDRESS	EcAddr;
782     UINT8			*EcData;
783     ACPI_STATUS			Status;
784 
785     ACPI_FUNCTION_TRACE_U32((char *)(uintptr_t)__func__, (UINT32)Address);
786 
787     if (Function != ACPI_READ && Function != ACPI_WRITE)
788 	return_ACPI_STATUS (AE_BAD_PARAMETER);
789     if (Width % 8 != 0 || Value == NULL || Context == NULL)
790 	return_ACPI_STATUS (AE_BAD_PARAMETER);
791     if (Address + Width / 8 > 256)
792 	return_ACPI_STATUS (AE_BAD_ADDRESS);
793 
794     /*
795      * If booting, check if we need to run the query handler.  If so, we
796      * we call it directly here since our thread taskq is not active yet.
797      */
798     if (cold || rebooting || sc->ec_suspending) {
799 	if ((EC_GET_CSR(sc) & EC_EVENT_SCI) &&
800 	    atomic_fetchadd_int(&sc->ec_sci_pend, 1) == 0) {
801 	    CTR0(KTR_ACPI, "ec running gpe handler directly");
802 	    EcGpeQueryHandler(sc);
803 	}
804     }
805 
806     /* Serialize with EcGpeQueryHandler() at transaction granularity. */
807     Status = EcLock(sc);
808     if (ACPI_FAILURE(Status))
809 	return_ACPI_STATUS (Status);
810 
811     /* If we can't start burst mode, continue anyway. */
812     Status = EcCommand(sc, EC_COMMAND_BURST_ENABLE);
813     if (ACPI_SUCCESS(Status)) {
814 	if (EC_GET_DATA(sc) == EC_BURST_ACK) {
815 	    CTR0(KTR_ACPI, "ec burst enabled");
816 	    sc->ec_burstactive = TRUE;
817 	}
818     }
819 
820     /* Perform the transaction(s), based on Width. */
821     EcAddr = Address;
822     EcData = (UINT8 *)Value;
823     if (Function == ACPI_READ)
824 	*Value = 0;
825     do {
826 	switch (Function) {
827 	case ACPI_READ:
828 	    Status = EcRead(sc, EcAddr, EcData);
829 	    break;
830 	case ACPI_WRITE:
831 	    Status = EcWrite(sc, EcAddr, *EcData);
832 	    break;
833 	}
834 	if (ACPI_FAILURE(Status))
835 	    break;
836 	EcAddr++;
837 	EcData++;
838     } while (EcAddr < Address + Width / 8);
839 
840     if (sc->ec_burstactive) {
841 	sc->ec_burstactive = FALSE;
842 	if (ACPI_SUCCESS(EcCommand(sc, EC_COMMAND_BURST_DISABLE)))
843 	    CTR0(KTR_ACPI, "ec disabled burst ok");
844     }
845 
846     EcUnlock(sc);
847     return_ACPI_STATUS (Status);
848 }
849 
850 static ACPI_STATUS
851 EcWaitEvent(struct acpi_ec_softc *sc, EC_EVENT Event, u_int gen_count)
852 {
853     static int	no_intr = 0;
854     ACPI_STATUS	Status;
855     int		count, i, need_poll, slp_ival;
856 
857     ACPI_SERIAL_ASSERT(ec);
858     Status = AE_NO_HARDWARE_RESPONSE;
859     need_poll = cold || rebooting || ec_polled_mode || sc->ec_suspending;
860 
861     /* Wait for event by polling or GPE (interrupt). */
862     if (need_poll) {
863 	count = (ec_timeout * 1000) / EC_POLL_DELAY;
864 	if (count == 0)
865 	    count = 1;
866 	DELAY(10);
867 	for (i = 0; i < count; i++) {
868 	    Status = EcCheckStatus(sc, "poll", Event);
869 	    if (ACPI_SUCCESS(Status))
870 		break;
871 	    DELAY(EC_POLL_DELAY);
872 	}
873     } else {
874 	slp_ival = hz / 1000;
875 	if (slp_ival != 0) {
876 	    count = ec_timeout;
877 	} else {
878 	    /* hz has less than 1 ms resolution so scale timeout. */
879 	    slp_ival = 1;
880 	    count = ec_timeout / (1000 / hz);
881 	}
882 
883 	/*
884 	 * Wait for the GPE to signal the status changed, checking the
885 	 * status register each time we get one.  It's possible to get a
886 	 * GPE for an event we're not interested in here (i.e., SCI for
887 	 * EC query).
888 	 */
889 	for (i = 0; i < count; i++) {
890 	    if (gen_count == sc->ec_gencount)
891 		tsleep(sc, 0, "ecgpe", slp_ival);
892 	    /*
893 	     * Record new generation count.  It's possible the GPE was
894 	     * just to notify us that a query is needed and we need to
895 	     * wait for a second GPE to signal the completion of the
896 	     * event we are actually waiting for.
897 	     */
898 	    Status = EcCheckStatus(sc, "sleep", Event);
899 	    if (ACPI_SUCCESS(Status)) {
900 		if (gen_count == sc->ec_gencount)
901 		    no_intr++;
902 		else
903 		    no_intr = 0;
904 		break;
905 	    }
906 	    gen_count = sc->ec_gencount;
907 	}
908 
909 	/*
910 	 * We finished waiting for the GPE and it never arrived.  Try to
911 	 * read the register once and trust whatever value we got.  This is
912 	 * the best we can do at this point.
913 	 */
914 	if (ACPI_FAILURE(Status))
915 	    Status = EcCheckStatus(sc, "sleep_end", Event);
916     }
917     if (!need_poll && no_intr > 10) {
918 	device_printf(sc->ec_dev,
919 	    "not getting interrupts, switched to polled mode\n");
920 	ec_polled_mode = 1;
921     }
922     if (ACPI_FAILURE(Status))
923 	    CTR0(KTR_ACPI, "error: ec wait timed out");
924     return (Status);
925 }
926 
927 static ACPI_STATUS
928 EcCommand(struct acpi_ec_softc *sc, EC_COMMAND cmd)
929 {
930     ACPI_STATUS	status;
931     EC_EVENT	event;
932     EC_STATUS	ec_status;
933     u_int	gen_count;
934 
935     ACPI_SERIAL_ASSERT(ec);
936 
937     /* Don't use burst mode if user disabled it. */
938     if (!ec_burst_mode && cmd == EC_COMMAND_BURST_ENABLE)
939 	return (AE_ERROR);
940 
941     /* Decide what to wait for based on command type. */
942     switch (cmd) {
943     case EC_COMMAND_READ:
944     case EC_COMMAND_WRITE:
945     case EC_COMMAND_BURST_DISABLE:
946 	event = EC_EVENT_INPUT_BUFFER_EMPTY;
947 	break;
948     case EC_COMMAND_QUERY:
949     case EC_COMMAND_BURST_ENABLE:
950 	event = EC_EVENT_OUTPUT_BUFFER_FULL;
951 	break;
952     default:
953 	device_printf(sc->ec_dev, "EcCommand: invalid command %#x\n", cmd);
954 	return (AE_BAD_PARAMETER);
955     }
956 
957     /*
958      * Ensure empty input buffer before issuing command.
959      * Use generation count of zero to force a quick check.
960      */
961     status = EcWaitEvent(sc, EC_EVENT_INPUT_BUFFER_EMPTY, 0);
962     if (ACPI_FAILURE(status))
963 	return (status);
964 
965     /* Run the command and wait for the chosen event. */
966     CTR1(KTR_ACPI, "ec running command %#x", cmd);
967     gen_count = sc->ec_gencount;
968     EC_SET_CSR(sc, cmd);
969     status = EcWaitEvent(sc, event, gen_count);
970     if (ACPI_SUCCESS(status)) {
971 	/* If we succeeded, burst flag should now be present. */
972 	if (cmd == EC_COMMAND_BURST_ENABLE) {
973 	    ec_status = EC_GET_CSR(sc);
974 	    if ((ec_status & EC_FLAG_BURST_MODE) == 0)
975 		status = AE_ERROR;
976 	}
977     } else
978 	device_printf(sc->ec_dev, "EcCommand: no response to %#x\n", cmd);
979     return (status);
980 }
981 
982 static ACPI_STATUS
983 EcRead(struct acpi_ec_softc *sc, UINT8 Address, UINT8 *Data)
984 {
985     ACPI_STATUS	status;
986     u_int gen_count;
987     int retry;
988 
989     ACPI_SERIAL_ASSERT(ec);
990     CTR1(KTR_ACPI, "ec read from %#x", Address);
991 
992     for (retry = 0; retry < 2; retry++) {
993 	status = EcCommand(sc, EC_COMMAND_READ);
994 	if (ACPI_FAILURE(status))
995 	    return (status);
996 
997 	gen_count = sc->ec_gencount;
998 	EC_SET_DATA(sc, Address);
999 	status = EcWaitEvent(sc, EC_EVENT_OUTPUT_BUFFER_FULL, gen_count);
1000 	if (ACPI_SUCCESS(status)) {
1001 	    *Data = EC_GET_DATA(sc);
1002 	    return (AE_OK);
1003 	}
1004 	if (ACPI_FAILURE(EcCheckStatus(sc, "retr_check",
1005 	    EC_EVENT_INPUT_BUFFER_EMPTY)))
1006 	    break;
1007     }
1008     device_printf(sc->ec_dev, "EcRead: failed waiting to get data\n");
1009     return (status);
1010 }
1011 
1012 static ACPI_STATUS
1013 EcWrite(struct acpi_ec_softc *sc, UINT8 Address, UINT8 Data)
1014 {
1015     ACPI_STATUS	status;
1016     u_int gen_count;
1017 
1018     ACPI_SERIAL_ASSERT(ec);
1019     CTR2(KTR_ACPI, "ec write to %#x, data %#x", Address, Data);
1020 
1021     status = EcCommand(sc, EC_COMMAND_WRITE);
1022     if (ACPI_FAILURE(status))
1023 	return (status);
1024 
1025     gen_count = sc->ec_gencount;
1026     EC_SET_DATA(sc, Address);
1027     status = EcWaitEvent(sc, EC_EVENT_INPUT_BUFFER_EMPTY, gen_count);
1028     if (ACPI_FAILURE(status)) {
1029 	device_printf(sc->ec_dev, "EcWrite: failed waiting for sent address\n");
1030 	return (status);
1031     }
1032 
1033     gen_count = sc->ec_gencount;
1034     EC_SET_DATA(sc, Data);
1035     status = EcWaitEvent(sc, EC_EVENT_INPUT_BUFFER_EMPTY, gen_count);
1036     if (ACPI_FAILURE(status)) {
1037 	device_printf(sc->ec_dev, "EcWrite: failed waiting for sent data\n");
1038 	return (status);
1039     }
1040 
1041     return (AE_OK);
1042 }
1043