xref: /freebsd/sys/dev/acpica/acpi_ec.c (revision 2a3e3873a1e4cd958f2b0f85d3b10cfa40575d30)
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/bus.h>
36 #include <sys/lock.h>
37 #include <sys/malloc.h>
38 #include <sys/module.h>
39 #include <sys/sx.h>
40 
41 #include <machine/bus.h>
42 #include <machine/resource.h>
43 #include <sys/rman.h>
44 
45 #include <contrib/dev/acpica/include/acpi.h>
46 #include <contrib/dev/acpica/include/accommon.h>
47 
48 #include <dev/acpica/acpivar.h>
49 
50 /* Hooks for the ACPI CA debugging infrastructure */
51 #define _COMPONENT	ACPI_EC
52 ACPI_MODULE_NAME("EC")
53 
54 /*
55  * EC_COMMAND:
56  * -----------
57  */
58 typedef UINT8				EC_COMMAND;
59 
60 #define EC_COMMAND_UNKNOWN		((EC_COMMAND) 0x00)
61 #define EC_COMMAND_READ			((EC_COMMAND) 0x80)
62 #define EC_COMMAND_WRITE		((EC_COMMAND) 0x81)
63 #define EC_COMMAND_BURST_ENABLE		((EC_COMMAND) 0x82)
64 #define EC_COMMAND_BURST_DISABLE	((EC_COMMAND) 0x83)
65 #define EC_COMMAND_QUERY		((EC_COMMAND) 0x84)
66 
67 /*
68  * EC_STATUS:
69  * ----------
70  * The encoding of the EC status register is illustrated below.
71  * Note that a set bit (1) indicates the property is TRUE
72  * (e.g. if bit 0 is set then the output buffer is full).
73  * +-+-+-+-+-+-+-+-+
74  * |7|6|5|4|3|2|1|0|
75  * +-+-+-+-+-+-+-+-+
76  *  | | | | | | | |
77  *  | | | | | | | +- Output Buffer Full?
78  *  | | | | | | +--- Input Buffer Full?
79  *  | | | | | +----- <reserved>
80  *  | | | | +------- Data Register is Command Byte?
81  *  | | | +--------- Burst Mode Enabled?
82  *  | | +----------- SCI Event?
83  *  | +------------- SMI Event?
84  *  +--------------- <reserved>
85  *
86  */
87 typedef UINT8				EC_STATUS;
88 
89 #define EC_FLAG_OUTPUT_BUFFER		((EC_STATUS) 0x01)
90 #define EC_FLAG_INPUT_BUFFER		((EC_STATUS) 0x02)
91 #define EC_FLAG_DATA_IS_CMD		((EC_STATUS) 0x08)
92 #define EC_FLAG_BURST_MODE		((EC_STATUS) 0x10)
93 
94 /*
95  * EC_EVENT:
96  * ---------
97  */
98 typedef UINT8				EC_EVENT;
99 
100 #define EC_EVENT_UNKNOWN		((EC_EVENT) 0x00)
101 #define EC_EVENT_OUTPUT_BUFFER_FULL	((EC_EVENT) 0x01)
102 #define EC_EVENT_INPUT_BUFFER_EMPTY	((EC_EVENT) 0x02)
103 #define EC_EVENT_SCI			((EC_EVENT) 0x20)
104 #define EC_EVENT_SMI			((EC_EVENT) 0x40)
105 
106 /* Data byte returned after burst enable indicating it was successful. */
107 #define EC_BURST_ACK			0x90
108 
109 /*
110  * Register access primitives
111  */
112 #define EC_GET_DATA(sc)							\
113 	bus_space_read_1((sc)->ec_data_tag, (sc)->ec_data_handle, 0)
114 
115 #define EC_SET_DATA(sc, v)						\
116 	bus_space_write_1((sc)->ec_data_tag, (sc)->ec_data_handle, 0, (v))
117 
118 #define EC_GET_CSR(sc)							\
119 	bus_space_read_1((sc)->ec_csr_tag, (sc)->ec_csr_handle, 0)
120 
121 #define EC_SET_CSR(sc, v)						\
122 	bus_space_write_1((sc)->ec_csr_tag, (sc)->ec_csr_handle, 0, (v))
123 
124 /* Additional params to pass from the probe routine */
125 struct acpi_ec_params {
126     int		glk;
127     int		gpe_bit;
128     ACPI_HANDLE	gpe_handle;
129     int		uid;
130 };
131 
132 /*
133  * Driver softc.
134  */
135 struct acpi_ec_softc {
136     device_t		ec_dev;
137     ACPI_HANDLE		ec_handle;
138     int			ec_uid;
139     ACPI_HANDLE		ec_gpehandle;
140     UINT8		ec_gpebit;
141 
142     int			ec_data_rid;
143     struct resource	*ec_data_res;
144     bus_space_tag_t	ec_data_tag;
145     bus_space_handle_t	ec_data_handle;
146 
147     int			ec_csr_rid;
148     struct resource	*ec_csr_res;
149     bus_space_tag_t	ec_csr_tag;
150     bus_space_handle_t	ec_csr_handle;
151 
152     int			ec_glk;
153     int			ec_glkhandle;
154     int			ec_burstactive;
155     int			ec_sci_pend;
156     volatile u_int	ec_gencount;
157     int			ec_suspending;
158 };
159 
160 /*
161  * XXX njl
162  * I couldn't find it in the spec but other implementations also use a
163  * value of 1 ms for the time to acquire global lock.
164  */
165 #define EC_LOCK_TIMEOUT	1000
166 
167 /* Default delay in microseconds between each run of the status polling loop. */
168 #define EC_POLL_DELAY	50
169 
170 /* Total time in ms spent waiting for a response from EC. */
171 #define EC_TIMEOUT	750
172 
173 #define EVENT_READY(event, status)			\
174 	(((event) == EC_EVENT_OUTPUT_BUFFER_FULL &&	\
175 	 ((status) & EC_FLAG_OUTPUT_BUFFER) != 0) ||	\
176 	 ((event) == EC_EVENT_INPUT_BUFFER_EMPTY && 	\
177 	 ((status) & EC_FLAG_INPUT_BUFFER) == 0))
178 
179 ACPI_SERIAL_DECL(ec, "ACPI embedded controller");
180 
181 static SYSCTL_NODE(_debug_acpi, OID_AUTO, ec, CTLFLAG_RD, NULL, "EC debugging");
182 
183 static int	ec_burst_mode;
184 TUNABLE_INT("debug.acpi.ec.burst", &ec_burst_mode);
185 SYSCTL_INT(_debug_acpi_ec, OID_AUTO, burst, CTLFLAG_RW, &ec_burst_mode, 0,
186     "Enable use of burst mode (faster for nearly all systems)");
187 static int	ec_polled_mode;
188 TUNABLE_INT("debug.acpi.ec.polled", &ec_polled_mode);
189 SYSCTL_INT(_debug_acpi_ec, OID_AUTO, polled, CTLFLAG_RW, &ec_polled_mode, 0,
190     "Force use of polled mode (only if interrupt mode doesn't work)");
191 static int	ec_timeout = EC_TIMEOUT;
192 TUNABLE_INT("debug.acpi.ec.timeout", &ec_timeout);
193 SYSCTL_INT(_debug_acpi_ec, OID_AUTO, timeout, CTLFLAG_RW, &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;
348     struct acpi_ec_params *params;
349     static char *ec_ids[] = { "PNP0C09", NULL };
350 
351     /* Check that this is a device and that EC is not disabled. */
352     if (acpi_get_type(dev) != ACPI_TYPE_DEVICE || acpi_disabled("ec"))
353 	return (ENXIO);
354 
355     /*
356      * If probed via ECDT, set description and continue.  Otherwise,
357      * we can access the namespace and make sure this is not a
358      * duplicate probe.
359      */
360     ret = ENXIO;
361     ecdt = 0;
362     buf.Pointer = NULL;
363     buf.Length = ACPI_ALLOCATE_BUFFER;
364     params = acpi_get_private(dev);
365     if (params != NULL) {
366 	ecdt = 1;
367 	ret = 0;
368     } else if (ACPI_ID_PROBE(device_get_parent(dev), dev, ec_ids)) {
369 	params = malloc(sizeof(struct acpi_ec_params), M_TEMP,
370 			M_WAITOK | M_ZERO);
371 	h = acpi_get_handle(dev);
372 
373 	/*
374 	 * Read the unit ID to check for duplicate attach and the
375 	 * global lock value to see if we should acquire it when
376 	 * accessing the EC.
377 	 */
378 	status = acpi_GetInteger(h, "_UID", &params->uid);
379 	if (ACPI_FAILURE(status))
380 	    params->uid = 0;
381 	status = acpi_GetInteger(h, "_GLK", &params->glk);
382 	if (ACPI_FAILURE(status))
383 	    params->glk = 0;
384 
385 	/*
386 	 * Evaluate the _GPE method to find the GPE bit used by the EC to
387 	 * signal status (SCI).  If it's a package, it contains a reference
388 	 * and GPE bit, similar to _PRW.
389 	 */
390 	status = AcpiEvaluateObject(h, "_GPE", NULL, &buf);
391 	if (ACPI_FAILURE(status)) {
392 	    device_printf(dev, "can't evaluate _GPE - %s\n",
393 			  AcpiFormatException(status));
394 	    goto out;
395 	}
396 	obj = (ACPI_OBJECT *)buf.Pointer;
397 	if (obj == NULL)
398 	    goto out;
399 
400 	switch (obj->Type) {
401 	case ACPI_TYPE_INTEGER:
402 	    params->gpe_handle = NULL;
403 	    params->gpe_bit = obj->Integer.Value;
404 	    break;
405 	case ACPI_TYPE_PACKAGE:
406 	    if (!ACPI_PKG_VALID(obj, 2))
407 		goto out;
408 	    params->gpe_handle =
409 		acpi_GetReference(NULL, &obj->Package.Elements[0]);
410 	    if (params->gpe_handle == NULL ||
411 		acpi_PkgInt32(obj, 1, &params->gpe_bit) != 0)
412 		goto out;
413 	    break;
414 	default:
415 	    device_printf(dev, "_GPE has invalid type %d\n", obj->Type);
416 	    goto out;
417 	}
418 
419 	/* Store the values we got from the namespace for attach. */
420 	acpi_set_private(dev, params);
421 
422 	/*
423 	 * Check for a duplicate probe.  This can happen when a probe
424 	 * via ECDT succeeded already.  If this is a duplicate, disable
425 	 * this device.
426 	 */
427 	peer = devclass_get_device(acpi_ec_devclass, params->uid);
428 	if (peer == NULL || !device_is_alive(peer))
429 	    ret = 0;
430 	else
431 	    device_disable(dev);
432     }
433 
434 out:
435     if (ret == 0) {
436 	snprintf(desc, sizeof(desc), "Embedded Controller: GPE %#x%s%s",
437 		 params->gpe_bit, (params->glk) ? ", GLK" : "",
438 		 ecdt ? ", ECDT" : "");
439 	device_set_desc_copy(dev, desc);
440     }
441 
442     if (ret > 0 && params)
443 	free(params, M_TEMP);
444     if (buf.Pointer)
445 	AcpiOsFree(buf.Pointer);
446     return (ret);
447 }
448 
449 static int
450 acpi_ec_attach(device_t dev)
451 {
452     struct acpi_ec_softc	*sc;
453     struct acpi_ec_params	*params;
454     ACPI_STATUS			Status;
455 
456     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
457 
458     /* Fetch/initialize softc (assumes softc is pre-zeroed). */
459     sc = device_get_softc(dev);
460     params = acpi_get_private(dev);
461     sc->ec_dev = dev;
462     sc->ec_handle = acpi_get_handle(dev);
463 
464     /* Retrieve previously probed values via device ivars. */
465     sc->ec_glk = params->glk;
466     sc->ec_gpebit = params->gpe_bit;
467     sc->ec_gpehandle = params->gpe_handle;
468     sc->ec_uid = params->uid;
469     sc->ec_suspending = FALSE;
470     acpi_set_private(dev, NULL);
471     free(params, M_TEMP);
472 
473     /* Attach bus resources for data and command/status ports. */
474     sc->ec_data_rid = 0;
475     sc->ec_data_res = bus_alloc_resource_any(sc->ec_dev, SYS_RES_IOPORT,
476 			&sc->ec_data_rid, RF_ACTIVE);
477     if (sc->ec_data_res == NULL) {
478 	device_printf(dev, "can't allocate data port\n");
479 	goto error;
480     }
481     sc->ec_data_tag = rman_get_bustag(sc->ec_data_res);
482     sc->ec_data_handle = rman_get_bushandle(sc->ec_data_res);
483 
484     sc->ec_csr_rid = 1;
485     sc->ec_csr_res = bus_alloc_resource_any(sc->ec_dev, SYS_RES_IOPORT,
486 			&sc->ec_csr_rid, RF_ACTIVE);
487     if (sc->ec_csr_res == NULL) {
488 	device_printf(dev, "can't allocate command/status port\n");
489 	goto error;
490     }
491     sc->ec_csr_tag = rman_get_bustag(sc->ec_csr_res);
492     sc->ec_csr_handle = rman_get_bushandle(sc->ec_csr_res);
493 
494     /*
495      * Install a handler for this EC's GPE bit.  We want edge-triggered
496      * behavior.
497      */
498     ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "attaching GPE handler\n"));
499     Status = AcpiInstallGpeHandler(sc->ec_gpehandle, sc->ec_gpebit,
500 		ACPI_GPE_EDGE_TRIGGERED, EcGpeHandler, sc);
501     if (ACPI_FAILURE(Status)) {
502 	device_printf(dev, "can't install GPE handler for %s - %s\n",
503 		      acpi_name(sc->ec_handle), AcpiFormatException(Status));
504 	goto error;
505     }
506 
507     /*
508      * Install address space handler
509      */
510     ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "attaching address space handler\n"));
511     Status = AcpiInstallAddressSpaceHandler(sc->ec_handle, ACPI_ADR_SPACE_EC,
512 		&EcSpaceHandler, &EcSpaceSetup, sc);
513     if (ACPI_FAILURE(Status)) {
514 	device_printf(dev, "can't install address space handler for %s - %s\n",
515 		      acpi_name(sc->ec_handle), AcpiFormatException(Status));
516 	goto error;
517     }
518 
519     /* Enable runtime GPEs for the handler. */
520     Status = AcpiEnableGpe(sc->ec_gpehandle, sc->ec_gpebit);
521     if (ACPI_FAILURE(Status)) {
522 	device_printf(dev, "AcpiEnableGpe failed: %s\n",
523 		      AcpiFormatException(Status));
524 	goto error;
525     }
526 
527     ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "acpi_ec_attach complete\n"));
528     return (0);
529 
530 error:
531     AcpiRemoveGpeHandler(sc->ec_gpehandle, sc->ec_gpebit, EcGpeHandler);
532     AcpiRemoveAddressSpaceHandler(sc->ec_handle, ACPI_ADR_SPACE_EC,
533 	EcSpaceHandler);
534     if (sc->ec_csr_res)
535 	bus_release_resource(sc->ec_dev, SYS_RES_IOPORT, sc->ec_csr_rid,
536 			     sc->ec_csr_res);
537     if (sc->ec_data_res)
538 	bus_release_resource(sc->ec_dev, SYS_RES_IOPORT, sc->ec_data_rid,
539 			     sc->ec_data_res);
540     return (ENXIO);
541 }
542 
543 static int
544 acpi_ec_suspend(device_t dev)
545 {
546     struct acpi_ec_softc	*sc;
547 
548     sc = device_get_softc(dev);
549     sc->ec_suspending = TRUE;
550     return (0);
551 }
552 
553 static int
554 acpi_ec_resume(device_t dev)
555 {
556     struct acpi_ec_softc	*sc;
557 
558     sc = device_get_softc(dev);
559     sc->ec_suspending = FALSE;
560     return (0);
561 }
562 
563 static int
564 acpi_ec_shutdown(device_t dev)
565 {
566     struct acpi_ec_softc	*sc;
567 
568     /* Disable the GPE so we don't get EC events during shutdown. */
569     sc = device_get_softc(dev);
570     AcpiDisableGpe(sc->ec_gpehandle, sc->ec_gpebit);
571     return (0);
572 }
573 
574 /* Methods to allow other devices (e.g., smbat) to read/write EC space. */
575 static int
576 acpi_ec_read_method(device_t dev, u_int addr, UINT64 *val, int width)
577 {
578     struct acpi_ec_softc *sc;
579     ACPI_STATUS status;
580 
581     sc = device_get_softc(dev);
582     status = EcSpaceHandler(ACPI_READ, addr, width * 8, val, sc, NULL);
583     if (ACPI_FAILURE(status))
584 	return (ENXIO);
585     return (0);
586 }
587 
588 static int
589 acpi_ec_write_method(device_t dev, u_int addr, UINT64 val, int width)
590 {
591     struct acpi_ec_softc *sc;
592     ACPI_STATUS status;
593 
594     sc = device_get_softc(dev);
595     status = EcSpaceHandler(ACPI_WRITE, addr, width * 8, &val, sc, NULL);
596     if (ACPI_FAILURE(status))
597 	return (ENXIO);
598     return (0);
599 }
600 
601 static ACPI_STATUS
602 EcCheckStatus(struct acpi_ec_softc *sc, const char *msg, EC_EVENT event)
603 {
604     ACPI_STATUS status;
605     EC_STATUS ec_status;
606 
607     status = AE_NO_HARDWARE_RESPONSE;
608     ec_status = EC_GET_CSR(sc);
609     if (sc->ec_burstactive && !(ec_status & EC_FLAG_BURST_MODE)) {
610 	CTR1(KTR_ACPI, "ec burst disabled in waitevent (%s)", msg);
611 	sc->ec_burstactive = FALSE;
612     }
613     if (EVENT_READY(event, ec_status)) {
614 	CTR2(KTR_ACPI, "ec %s wait ready, status %#x", msg, ec_status);
615 	status = AE_OK;
616     }
617     return (status);
618 }
619 
620 static void
621 EcGpeQueryHandler(void *Context)
622 {
623     struct acpi_ec_softc	*sc = (struct acpi_ec_softc *)Context;
624     UINT8			Data;
625     ACPI_STATUS			Status;
626     int				retry, sci_enqueued;
627     char			qxx[5];
628 
629     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
630     KASSERT(Context != NULL, ("EcGpeQueryHandler called with NULL"));
631 
632     /* Serialize user access with EcSpaceHandler(). */
633     Status = EcLock(sc);
634     if (ACPI_FAILURE(Status)) {
635 	device_printf(sc->ec_dev, "GpeQuery lock error: %s\n",
636 	    AcpiFormatException(Status));
637 	return;
638     }
639 
640     /*
641      * Send a query command to the EC to find out which _Qxx call it
642      * wants to make.  This command clears the SCI bit and also the
643      * interrupt source since we are edge-triggered.  To prevent the GPE
644      * that may arise from running the query from causing another query
645      * to be queued, we clear the pending flag only after running it.
646      */
647     sci_enqueued = sc->ec_sci_pend;
648     for (retry = 0; retry < 2; retry++) {
649 	Status = EcCommand(sc, EC_COMMAND_QUERY);
650 	if (ACPI_SUCCESS(Status))
651 	    break;
652 	if (ACPI_SUCCESS(EcCheckStatus(sc, "retr_check",
653 	    EC_EVENT_INPUT_BUFFER_EMPTY)))
654 	    continue;
655 	else
656 	    break;
657     }
658     sc->ec_sci_pend = FALSE;
659     if (ACPI_FAILURE(Status)) {
660 	EcUnlock(sc);
661 	device_printf(sc->ec_dev, "GPE query failed: %s\n",
662 	    AcpiFormatException(Status));
663 	return;
664     }
665     Data = EC_GET_DATA(sc);
666 
667     /*
668      * We have to unlock before running the _Qxx method below since that
669      * method may attempt to read/write from EC address space, causing
670      * recursive acquisition of the lock.
671      */
672     EcUnlock(sc);
673 
674     /* Ignore the value for "no outstanding event". (13.3.5) */
675     CTR2(KTR_ACPI, "ec query ok,%s running _Q%02X", Data ? "" : " not", Data);
676     if (Data == 0)
677 	return;
678 
679     /* Evaluate _Qxx to respond to the controller. */
680     snprintf(qxx, sizeof(qxx), "_Q%02X", Data);
681     AcpiUtStrupr(qxx);
682     Status = AcpiEvaluateObject(sc->ec_handle, qxx, NULL, NULL);
683     if (ACPI_FAILURE(Status) && Status != AE_NOT_FOUND) {
684 	device_printf(sc->ec_dev, "evaluation of query method %s failed: %s\n",
685 	    qxx, AcpiFormatException(Status));
686     }
687 
688     /* Reenable runtime GPE if its execution was deferred. */
689     if (sci_enqueued) {
690 	Status = AcpiFinishGpe(sc->ec_gpehandle, sc->ec_gpebit);
691 	if (ACPI_FAILURE(Status))
692 	    device_printf(sc->ec_dev, "reenabling runtime GPE failed: %s\n",
693 		AcpiFormatException(Status));
694     }
695 }
696 
697 /*
698  * The GPE handler is called when IBE/OBF or SCI events occur.  We are
699  * called from an unknown lock context.
700  */
701 static UINT32
702 EcGpeHandler(ACPI_HANDLE GpeDevice, UINT32 GpeNumber, void *Context)
703 {
704     struct acpi_ec_softc *sc = Context;
705     ACPI_STATUS		       Status;
706     EC_STATUS		       EcStatus;
707 
708     KASSERT(Context != NULL, ("EcGpeHandler called with NULL"));
709     CTR0(KTR_ACPI, "ec gpe handler start");
710 
711     /*
712      * Notify EcWaitEvent() that the status register is now fresh.  If we
713      * didn't do this, it wouldn't be possible to distinguish an old IBE
714      * from a new one, for example when doing a write transaction (writing
715      * address and then data values.)
716      */
717     atomic_add_int(&sc->ec_gencount, 1);
718     wakeup(sc);
719 
720     /*
721      * If the EC_SCI bit of the status register is set, queue a query handler.
722      * It will run the query and _Qxx method later, under the lock.
723      */
724     EcStatus = EC_GET_CSR(sc);
725     if ((EcStatus & EC_EVENT_SCI) && !sc->ec_sci_pend) {
726 	CTR0(KTR_ACPI, "ec gpe queueing query handler");
727 	Status = AcpiOsExecute(OSL_GPE_HANDLER, EcGpeQueryHandler, Context);
728 	if (ACPI_SUCCESS(Status)) {
729 	    sc->ec_sci_pend = TRUE;
730 	    return (0);
731 	} else
732 	    printf("EcGpeHandler: queuing GPE query handler failed\n");
733     }
734     return (ACPI_REENABLE_GPE);
735 }
736 
737 static ACPI_STATUS
738 EcSpaceSetup(ACPI_HANDLE Region, UINT32 Function, void *Context,
739 	     void **RegionContext)
740 {
741 
742     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
743 
744     /*
745      * If deactivating a region, always set the output to NULL.  Otherwise,
746      * just pass the context through.
747      */
748     if (Function == ACPI_REGION_DEACTIVATE)
749 	*RegionContext = NULL;
750     else
751 	*RegionContext = Context;
752 
753     return_ACPI_STATUS (AE_OK);
754 }
755 
756 static ACPI_STATUS
757 EcSpaceHandler(UINT32 Function, ACPI_PHYSICAL_ADDRESS Address, UINT32 Width,
758 	       UINT64 *Value, void *Context, void *RegionContext)
759 {
760     struct acpi_ec_softc	*sc = (struct acpi_ec_softc *)Context;
761     ACPI_PHYSICAL_ADDRESS	EcAddr;
762     UINT8			*EcData;
763     ACPI_STATUS			Status;
764 
765     ACPI_FUNCTION_TRACE_U32((char *)(uintptr_t)__func__, (UINT32)Address);
766 
767     if (Function != ACPI_READ && Function != ACPI_WRITE)
768 	return_ACPI_STATUS (AE_BAD_PARAMETER);
769     if (Width % 8 != 0 || Value == NULL || Context == NULL)
770 	return_ACPI_STATUS (AE_BAD_PARAMETER);
771     if (Address + Width / 8 > 256)
772 	return_ACPI_STATUS (AE_BAD_ADDRESS);
773 
774     /*
775      * If booting, check if we need to run the query handler.  If so, we
776      * we call it directly here since our thread taskq is not active yet.
777      */
778     if (cold || rebooting || sc->ec_suspending) {
779 	if ((EC_GET_CSR(sc) & EC_EVENT_SCI)) {
780 	    CTR0(KTR_ACPI, "ec running gpe handler directly");
781 	    EcGpeQueryHandler(sc);
782 	}
783     }
784 
785     /* Serialize with EcGpeQueryHandler() at transaction granularity. */
786     Status = EcLock(sc);
787     if (ACPI_FAILURE(Status))
788 	return_ACPI_STATUS (Status);
789 
790     /* If we can't start burst mode, continue anyway. */
791     Status = EcCommand(sc, EC_COMMAND_BURST_ENABLE);
792     if (ACPI_SUCCESS(Status)) {
793 	if (EC_GET_DATA(sc) == EC_BURST_ACK) {
794 	    CTR0(KTR_ACPI, "ec burst enabled");
795 	    sc->ec_burstactive = TRUE;
796 	}
797     }
798 
799     /* Perform the transaction(s), based on Width. */
800     EcAddr = Address;
801     EcData = (UINT8 *)Value;
802     if (Function == ACPI_READ)
803 	*Value = 0;
804     do {
805 	switch (Function) {
806 	case ACPI_READ:
807 	    Status = EcRead(sc, EcAddr, EcData);
808 	    break;
809 	case ACPI_WRITE:
810 	    Status = EcWrite(sc, EcAddr, *EcData);
811 	    break;
812 	}
813 	if (ACPI_FAILURE(Status))
814 	    break;
815 	EcAddr++;
816 	EcData++;
817     } while (EcAddr < Address + Width / 8);
818 
819     if (sc->ec_burstactive) {
820 	sc->ec_burstactive = FALSE;
821 	if (ACPI_SUCCESS(EcCommand(sc, EC_COMMAND_BURST_DISABLE)))
822 	    CTR0(KTR_ACPI, "ec disabled burst ok");
823     }
824 
825     EcUnlock(sc);
826     return_ACPI_STATUS (Status);
827 }
828 
829 static ACPI_STATUS
830 EcWaitEvent(struct acpi_ec_softc *sc, EC_EVENT Event, u_int gen_count)
831 {
832     static int	no_intr = 0;
833     ACPI_STATUS	Status;
834     int		count, i, need_poll, slp_ival;
835 
836     ACPI_SERIAL_ASSERT(ec);
837     Status = AE_NO_HARDWARE_RESPONSE;
838     need_poll = cold || rebooting || ec_polled_mode || sc->ec_suspending;
839 
840     /* Wait for event by polling or GPE (interrupt). */
841     if (need_poll) {
842 	count = (ec_timeout * 1000) / EC_POLL_DELAY;
843 	if (count == 0)
844 	    count = 1;
845 	DELAY(10);
846 	for (i = 0; i < count; i++) {
847 	    Status = EcCheckStatus(sc, "poll", Event);
848 	    if (ACPI_SUCCESS(Status))
849 		break;
850 	    DELAY(EC_POLL_DELAY);
851 	}
852     } else {
853 	slp_ival = hz / 1000;
854 	if (slp_ival != 0) {
855 	    count = ec_timeout;
856 	} else {
857 	    /* hz has less than 1 ms resolution so scale timeout. */
858 	    slp_ival = 1;
859 	    count = ec_timeout / (1000 / hz);
860 	}
861 
862 	/*
863 	 * Wait for the GPE to signal the status changed, checking the
864 	 * status register each time we get one.  It's possible to get a
865 	 * GPE for an event we're not interested in here (i.e., SCI for
866 	 * EC query).
867 	 */
868 	for (i = 0; i < count; i++) {
869 	    if (gen_count == sc->ec_gencount)
870 		tsleep(sc, 0, "ecgpe", slp_ival);
871 	    /*
872 	     * Record new generation count.  It's possible the GPE was
873 	     * just to notify us that a query is needed and we need to
874 	     * wait for a second GPE to signal the completion of the
875 	     * event we are actually waiting for.
876 	     */
877 	    Status = EcCheckStatus(sc, "sleep", Event);
878 	    if (ACPI_SUCCESS(Status)) {
879 		if (gen_count == sc->ec_gencount)
880 		    no_intr++;
881 		else
882 		    no_intr = 0;
883 		break;
884 	    }
885 	    gen_count = sc->ec_gencount;
886 	}
887 
888 	/*
889 	 * We finished waiting for the GPE and it never arrived.  Try to
890 	 * read the register once and trust whatever value we got.  This is
891 	 * the best we can do at this point.
892 	 */
893 	if (ACPI_FAILURE(Status))
894 	    Status = EcCheckStatus(sc, "sleep_end", Event);
895     }
896     if (!need_poll && no_intr > 10) {
897 	device_printf(sc->ec_dev,
898 	    "not getting interrupts, switched to polled mode\n");
899 	ec_polled_mode = 1;
900     }
901     if (ACPI_FAILURE(Status))
902 	    CTR0(KTR_ACPI, "error: ec wait timed out");
903     return (Status);
904 }
905 
906 static ACPI_STATUS
907 EcCommand(struct acpi_ec_softc *sc, EC_COMMAND cmd)
908 {
909     ACPI_STATUS	status;
910     EC_EVENT	event;
911     EC_STATUS	ec_status;
912     u_int	gen_count;
913 
914     ACPI_SERIAL_ASSERT(ec);
915 
916     /* Don't use burst mode if user disabled it. */
917     if (!ec_burst_mode && cmd == EC_COMMAND_BURST_ENABLE)
918 	return (AE_ERROR);
919 
920     /* Decide what to wait for based on command type. */
921     switch (cmd) {
922     case EC_COMMAND_READ:
923     case EC_COMMAND_WRITE:
924     case EC_COMMAND_BURST_DISABLE:
925 	event = EC_EVENT_INPUT_BUFFER_EMPTY;
926 	break;
927     case EC_COMMAND_QUERY:
928     case EC_COMMAND_BURST_ENABLE:
929 	event = EC_EVENT_OUTPUT_BUFFER_FULL;
930 	break;
931     default:
932 	device_printf(sc->ec_dev, "EcCommand: invalid command %#x\n", cmd);
933 	return (AE_BAD_PARAMETER);
934     }
935 
936     /*
937      * Ensure empty input buffer before issuing command.
938      * Use generation count of zero to force a quick check.
939      */
940     status = EcWaitEvent(sc, EC_EVENT_INPUT_BUFFER_EMPTY, 0);
941     if (ACPI_FAILURE(status))
942 	return (status);
943 
944     /* Run the command and wait for the chosen event. */
945     CTR1(KTR_ACPI, "ec running command %#x", cmd);
946     gen_count = sc->ec_gencount;
947     EC_SET_CSR(sc, cmd);
948     status = EcWaitEvent(sc, event, gen_count);
949     if (ACPI_SUCCESS(status)) {
950 	/* If we succeeded, burst flag should now be present. */
951 	if (cmd == EC_COMMAND_BURST_ENABLE) {
952 	    ec_status = EC_GET_CSR(sc);
953 	    if ((ec_status & EC_FLAG_BURST_MODE) == 0)
954 		status = AE_ERROR;
955 	}
956     } else
957 	device_printf(sc->ec_dev, "EcCommand: no response to %#x\n", cmd);
958     return (status);
959 }
960 
961 static ACPI_STATUS
962 EcRead(struct acpi_ec_softc *sc, UINT8 Address, UINT8 *Data)
963 {
964     ACPI_STATUS	status;
965     u_int gen_count;
966     int retry;
967 
968     ACPI_SERIAL_ASSERT(ec);
969     CTR1(KTR_ACPI, "ec read from %#x", Address);
970 
971     for (retry = 0; retry < 2; retry++) {
972 	status = EcCommand(sc, EC_COMMAND_READ);
973 	if (ACPI_FAILURE(status))
974 	    return (status);
975 
976 	gen_count = sc->ec_gencount;
977 	EC_SET_DATA(sc, Address);
978 	status = EcWaitEvent(sc, EC_EVENT_OUTPUT_BUFFER_FULL, gen_count);
979 	if (ACPI_FAILURE(status)) {
980 	    if (ACPI_SUCCESS(EcCheckStatus(sc, "retr_check",
981 		EC_EVENT_INPUT_BUFFER_EMPTY)))
982 		continue;
983 	    else
984 		break;
985 	}
986 	*Data = EC_GET_DATA(sc);
987 	return (AE_OK);
988     }
989     device_printf(sc->ec_dev, "EcRead: failed waiting to get data\n");
990     return (status);
991 }
992 
993 static ACPI_STATUS
994 EcWrite(struct acpi_ec_softc *sc, UINT8 Address, UINT8 Data)
995 {
996     ACPI_STATUS	status;
997     u_int gen_count;
998 
999     ACPI_SERIAL_ASSERT(ec);
1000     CTR2(KTR_ACPI, "ec write to %#x, data %#x", Address, Data);
1001 
1002     status = EcCommand(sc, EC_COMMAND_WRITE);
1003     if (ACPI_FAILURE(status))
1004 	return (status);
1005 
1006     gen_count = sc->ec_gencount;
1007     EC_SET_DATA(sc, Address);
1008     status = EcWaitEvent(sc, EC_EVENT_INPUT_BUFFER_EMPTY, gen_count);
1009     if (ACPI_FAILURE(status)) {
1010 	device_printf(sc->ec_dev, "EcWrite: failed waiting for sent address\n");
1011 	return (status);
1012     }
1013 
1014     gen_count = sc->ec_gencount;
1015     EC_SET_DATA(sc, Data);
1016     status = EcWaitEvent(sc, EC_EVENT_INPUT_BUFFER_EMPTY, gen_count);
1017     if (ACPI_FAILURE(status)) {
1018 	device_printf(sc->ec_dev, "EcWrite: failed waiting for sent data\n");
1019 	return (status);
1020     }
1021 
1022     return (AE_OK);
1023 }
1024