xref: /illumos-gate/usr/src/uts/sun4u/io/pmc.c (revision f3041bfa)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*
27  * Driver for the Power Management Controller (logical unit 8) of the
28  * PC87317 SuperI/O chip. The PMC contains the hardware watchdog timer.
29  */
30 
31 #include <sys/types.h>
32 #include <sys/time.h>
33 #include <sys/cmn_err.h>
34 #include <sys/param.h>
35 #include <sys/modctl.h>
36 #include <sys/conf.h>
37 #include <sys/stat.h>
38 #include <sys/clock.h>
39 #include <sys/reboot.h>
40 #include <sys/ddi.h>
41 #include <sys/sunddi.h>
42 #include <sys/file.h>
43 #include <sys/note.h>
44 
45 #ifdef	DEBUG
46 int pmc_debug_flag = 0;
47 #define	DPRINTF(ARGLIST) if (pmc_debug_flag) printf ARGLIST;
48 #else
49 #define	DPRINTF(ARGLIST)
50 #endif /* DEBUG */
51 
52 /* Driver soft state structure */
53 typedef struct pmc {
54 	dev_info_t		*dip;
55 	ddi_acc_handle_t	pmc_handle;
56 } pmc_t;
57 
58 static void *pmc_soft_state;
59 static int instance = -1;
60 
61 /* dev_ops and cb_ops entry point function declarations */
62 static int pmc_attach(dev_info_t *, ddi_attach_cmd_t);
63 static int pmc_detach(dev_info_t *, ddi_detach_cmd_t);
64 static int pmc_getinfo(dev_info_t *, ddi_info_cmd_t, void *, void **);
65 
66 /* hardware watchdog parameters */
67 static uint_t pmc_set_watchdog_timer(uint_t);
68 static uint_t pmc_clear_watchdog_timer(void);
69 
70 extern volatile uint8_t	*v_pmc_addr_reg;
71 extern volatile uint8_t	*v_pmc_data_reg;
72 extern int		watchdog_enable;
73 extern int		watchdog_available;
74 extern int		watchdog_activated;
75 extern int		boothowto;
76 extern uint_t		watchdog_timeout_seconds;
77 
78 /*
79  * Power Management Registers and values
80  */
81 #define	PMC_WDTO	0x05	/* Watchdog Time Out */
82 #define	PMC_CLEAR_WDTO	0x00
83 
84 struct cb_ops pmc_cb_ops = {
85 	nodev,
86 	nodev,
87 	nodev,
88 	nodev,
89 	nodev,			/* dump */
90 	nodev,
91 	nodev,
92 	nodev,
93 	nodev,			/* devmap */
94 	nodev,
95 	nodev,
96 	nochpoll,
97 	ddi_prop_op,
98 	NULL,			/* for STREAMS drivers */
99 	D_NEW | D_MP,		/* driver compatibility flag */
100 	CB_REV,
101 	nodev,
102 	nodev
103 };
104 
105 static struct dev_ops pmc_dev_ops = {
106 	DEVO_REV,			/* driver build version */
107 	0,				/* device reference count */
108 	pmc_getinfo,
109 	nulldev,
110 	nulldev,			/* probe */
111 	pmc_attach,
112 	pmc_detach,
113 	nulldev,			/* reset */
114 	&pmc_cb_ops,
115 	(struct bus_ops *)NULL,
116 	nulldev				/* power */
117 };
118 
119 /* module configuration stuff */
120 extern struct mod_ops mod_driverops;
121 static struct modldrv modldrv = {
122 	&mod_driverops,
123 	"pmc driver",
124 	&pmc_dev_ops
125 };
126 static struct modlinkage modlinkage = {
127 	MODREV_1,
128 	&modldrv,
129 	0
130 };
131 
132 
133 int
134 _init(void)
135 {
136 	int e;
137 
138 	e = ddi_soft_state_init(&pmc_soft_state, sizeof (pmc_t), 1);
139 	if (e != 0) {
140 		DPRINTF(("_init: ddi_soft_state_init failed\n"));
141 		return (e);
142 	}
143 
144 	e = mod_install(&modlinkage);
145 	if (e != 0) {
146 		DPRINTF(("_init: mod_install failed\n"));
147 		ddi_soft_state_fini(&pmc_soft_state);
148 		return (e);
149 	}
150 
151 	if (v_pmc_addr_reg != NULL) {
152 		tod_ops.tod_set_watchdog_timer = pmc_set_watchdog_timer;
153 		tod_ops.tod_clear_watchdog_timer = pmc_clear_watchdog_timer;
154 
155 		/*
156 		 * See if the user has enabled the watchdog timer, and if
157 		 * it's available.
158 		 */
159 		if (watchdog_enable) {
160 			if (!watchdog_available) {
161 				cmn_err(CE_WARN, "pmc: Hardware watchdog "
162 					"unavailable");
163 			} else if (boothowto & RB_DEBUG) {
164 				watchdog_available = 0;
165 				cmn_err(CE_WARN, "pmc: kernel debugger "
166 					"detected: hardware watchdog disabled");
167 			}
168 		}
169 	}
170 	return (e);
171 }
172 
173 int
174 _fini(void)
175 {
176 	int e;
177 
178 	if (v_pmc_addr_reg != NULL)
179 		return (DDI_FAILURE);
180 	else {
181 		e = mod_remove(&modlinkage);
182 		if (e != 0)
183 			return (e);
184 
185 		ddi_soft_state_fini(&pmc_soft_state);
186 		return (DDI_SUCCESS);
187 	}
188 }
189 
190 
191 int
192 _info(struct modinfo *modinfop)
193 {
194 	return (mod_info(&modlinkage, modinfop));
195 }
196 
197 static int
198 pmc_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd, void *arg, void **result)
199 {
200 	_NOTE(ARGUNUSED(dip))
201 
202 	pmc_t	*pmcp;
203 	int	instance;
204 
205 	switch (cmd) {
206 	case DDI_INFO_DEVT2DEVINFO:
207 		instance = getminor((dev_t)arg);
208 		pmcp = (pmc_t *)ddi_get_soft_state(pmc_soft_state, instance);
209 		if (pmcp == NULL) {
210 			*result = (void *)NULL;
211 			return (DDI_FAILURE);
212 		}
213 		*result = (void *)pmcp->dip;
214 		return (DDI_SUCCESS);
215 
216 	case DDI_INFO_DEVT2INSTANCE:
217 		*result = (void *)(uintptr_t)getminor((dev_t)arg);
218 		return (DDI_SUCCESS);
219 
220 	default:
221 		return (DDI_FAILURE);
222 	}
223 }
224 
225 
226 static int
227 pmc_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
228 {
229 	pmc_t	*pmcp;
230 	uint_t	wd_timout;
231 
232 	switch (cmd) {
233 	case DDI_ATTACH:
234 		break;
235 	case DDI_RESUME:
236 		if (v_pmc_addr_reg != NULL && watchdog_enable) {
237 			int ret = 0;
238 			wd_timout = watchdog_timeout_seconds;
239 			mutex_enter(&tod_lock);
240 			ret = tod_ops.tod_set_watchdog_timer(wd_timout);
241 			mutex_exit(&tod_lock);
242 			if (ret == 0)
243 				return (DDI_FAILURE);
244 		}
245 		return (DDI_SUCCESS);
246 	default:
247 		return (DDI_FAILURE);
248 	}
249 
250 	if (instance != -1) {
251 		DPRINTF(("pmc_attach: Another instance is already attached."));
252 		return (DDI_FAILURE);
253 	}
254 
255 	instance = ddi_get_instance(dip);
256 
257 	if (ddi_soft_state_zalloc(pmc_soft_state, instance) != DDI_SUCCESS) {
258 		DPRINTF(("pmc_attach: Failed to allocate soft state."));
259 		return (DDI_FAILURE);
260 	}
261 
262 	pmcp = (pmc_t *)ddi_get_soft_state(pmc_soft_state, instance);
263 	pmcp->dip = dip;
264 
265 	return (DDI_SUCCESS);
266 }
267 
268 static int
269 pmc_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
270 {
271 	_NOTE(ARGUNUSED(dip))
272 
273 	pmc_t	*pmcp;
274 
275 	switch (cmd) {
276 	case DDI_DETACH:
277 		/* allow detach if no hardware watchdog */
278 		if (v_pmc_addr_reg == NULL || !watchdog_activated) {
279 			pmcp = (pmc_t *)ddi_get_soft_state(pmc_soft_state,
280 				instance);
281 			if (pmcp == NULL)
282 				return (ENXIO);
283 			ddi_soft_state_free(pmc_soft_state, instance);
284 			return (DDI_SUCCESS);
285 		} else
286 			return (DDI_FAILURE);
287 	case DDI_SUSPEND:
288 		if (v_pmc_addr_reg != NULL && watchdog_activated) {
289 			mutex_enter(&tod_lock);
290 			(void) tod_ops.tod_clear_watchdog_timer();
291 			mutex_exit(&tod_lock);
292 		}
293 		return (DDI_SUCCESS);
294 	default:
295 		return (DDI_FAILURE);
296 	}
297 
298 }
299 
300 /*
301  * Set the hardware watchdog timer; returning what we set it to.
302  */
303 static uint_t
304 pmc_set_watchdog_timer(uint_t timeoutval)
305 {
306 	uint_t timeoutval_minutes;
307 	ASSERT(MUTEX_HELD(&tod_lock));
308 
309 	/* sanity checks */
310 	if (watchdog_enable == 0 || watchdog_available == 0 ||
311 	    timeoutval == 0)
312 		return (0);
313 
314 	/*
315 	 * Historically the timer has been counted out in seconds.
316 	 * The PC87317 counts the timeout in minutes. The default
317 	 * timeout is 10 seconds; the least we can do is one minute.
318 	 */
319 	timeoutval_minutes = (timeoutval + 59) / 60;
320 	if (timeoutval_minutes > UINT8_MAX)
321 		return (0);
322 
323 	*v_pmc_addr_reg = (uint8_t)PMC_WDTO;
324 	*v_pmc_data_reg = (uint8_t)timeoutval_minutes;
325 	watchdog_activated = 1;
326 
327 	/* we'll still return seconds */
328 	return (timeoutval_minutes * 60);
329 }
330 
331 /*
332  * Clear the hardware watchdog timer; returning what it was set to.
333  */
334 static uint_t
335 pmc_clear_watchdog_timer(void)
336 {
337 	uint_t	wd_timeout;
338 
339 	ASSERT(MUTEX_HELD(&tod_lock));
340 	if (watchdog_activated == 0)
341 		return (0);
342 
343 	*v_pmc_addr_reg = (uint8_t)PMC_WDTO;
344 	wd_timeout = (uint_t)*v_pmc_data_reg;
345 	*v_pmc_data_reg = (uint8_t)PMC_CLEAR_WDTO;
346 	watchdog_activated = 0;
347 
348 	/* return seconds */
349 	return (wd_timeout * 60);
350 }
351