xref: /freebsd/sys/arm/ti/ti_scm.c (revision 09d325677d53a12c79a43664ff29871e92247629)
1 /*
2  * Copyright (c) 2010
3  *	Ben Gray <ben.r.gray@gmail.com>.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by Ben Gray.
17  * 4. The name of the company nor the name of the author may be used to
18  *    endorse or promote products derived from this software without specific
19  *    prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY BEN GRAY ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL BEN GRAY BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
25  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
26  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
27  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
28  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
29  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
30  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 /**
34  *	SCM - System Control Module
35  *
36  *	Hopefully in the end this module will contain a bunch of utility functions
37  *	for configuring and querying the general system control registers, but for
38  *	now it only does pin(pad) multiplexing.
39  *
40  *	This is different from the GPIO module in that it is used to configure the
41  *	pins between modules not just GPIO input/output.
42  *
43  *	This file contains the generic top level driver, however it relies on chip
44  *	specific settings and therefore expects an array of ti_scm_padconf structs
45  *	call ti_padconf_devmap to be located somewhere in the kernel.
46  *
47  */
48 #include <sys/cdefs.h>
49 __FBSDID("$FreeBSD$");
50 
51 #include <sys/param.h>
52 #include <sys/systm.h>
53 #include <sys/kernel.h>
54 #include <sys/module.h>
55 #include <sys/bus.h>
56 #include <sys/resource.h>
57 #include <sys/rman.h>
58 #include <sys/lock.h>
59 #include <sys/mutex.h>
60 
61 #include <machine/bus.h>
62 #include <machine/cpu.h>
63 #include <machine/cpufunc.h>
64 #include <machine/resource.h>
65 
66 #include <dev/fdt/fdt_common.h>
67 #include <dev/ofw/openfirm.h>
68 #include <dev/ofw/ofw_bus.h>
69 #include <dev/ofw/ofw_bus_subr.h>
70 
71 #include "ti_scm.h"
72 
73 static struct resource_spec ti_scm_res_spec[] = {
74 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },	/* Control memory window */
75 	{ -1, 0 }
76 };
77 
78 static struct ti_scm_softc *ti_scm_sc;
79 
80 #define	ti_scm_read_2(sc, reg)		\
81     bus_space_read_2((sc)->sc_bst, (sc)->sc_bsh, (reg))
82 #define	ti_scm_write_2(sc, reg, val)		\
83     bus_space_write_2((sc)->sc_bst, (sc)->sc_bsh, (reg), (val))
84 #define	ti_scm_read_4(sc, reg)		\
85     bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg))
86 #define	ti_scm_write_4(sc, reg, val)		\
87     bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val))
88 
89 
90 /**
91  *	ti_padconf_devmap - Array of pins, should be defined one per SoC
92  *
93  *	This array is typically defined in one of the targeted *_scm_pinumx.c
94  *	files and is specific to the given SoC platform. Each entry in the array
95  *	corresponds to an individual pin.
96  */
97 extern const struct ti_scm_device ti_scm_dev;
98 
99 
100 /**
101  *	ti_scm_padconf_from_name - searches the list of pads and returns entry
102  *	                             with matching ball name.
103  *	@ballname: the name of the ball
104  *
105  *	RETURNS:
106  *	A pointer to the matching padconf or NULL if the ball wasn't found.
107  */
108 static const struct ti_scm_padconf*
109 ti_scm_padconf_from_name(const char *ballname)
110 {
111 	const struct ti_scm_padconf *padconf;
112 
113 	padconf = ti_scm_dev.padconf;
114 	while (padconf->ballname != NULL) {
115 		if (strcmp(ballname, padconf->ballname) == 0)
116 			return(padconf);
117 		padconf++;
118 	}
119 
120 	return (NULL);
121 }
122 
123 /**
124  *	ti_scm_padconf_set_internal - sets the muxmode and state for a pad/pin
125  *	@padconf: pointer to the pad structure
126  *	@muxmode: the name of the mode to use for the pin, i.e. "uart1_rx"
127  *	@state: the state to put the pad/pin in, i.e. PADCONF_PIN_???
128  *
129  *
130  *	LOCKING:
131  *	Internally locks it's own context.
132  *
133  *	RETURNS:
134  *	0 on success.
135  *	EINVAL if pin requested is outside valid range or already in use.
136  */
137 static int
138 ti_scm_padconf_set_internal(struct ti_scm_softc *sc,
139     const struct ti_scm_padconf *padconf,
140     const char *muxmode, unsigned int state)
141 {
142 	unsigned int mode;
143 	uint16_t reg_val;
144 
145 	/* populate the new value for the PADCONF register */
146 	reg_val = (uint16_t)(state & ti_scm_dev.padconf_sate_mask);
147 
148 	/* find the new mode requested */
149 	for (mode = 0; mode < 8; mode++) {
150 		if ((padconf->muxmodes[mode] != NULL) &&
151 		    (strcmp(padconf->muxmodes[mode], muxmode) == 0)) {
152 			break;
153 		}
154 	}
155 
156 	/* couldn't find the mux mode */
157 	if (mode >= 8) {
158 		printf("Invalid mode \"%s\"\n", muxmode);
159 		return (EINVAL);
160 	}
161 
162 	/* set the mux mode */
163 	reg_val |= (uint16_t)(mode & ti_scm_dev.padconf_muxmode_mask);
164 
165 	if (bootverbose)
166 		device_printf(sc->sc_dev, "setting internal %x for %s\n",
167 		    reg_val, muxmode);
168 	/* write the register value (16-bit writes) */
169 	ti_scm_write_2(sc, padconf->reg_off, reg_val);
170 
171 	return (0);
172 }
173 
174 /**
175  *	ti_scm_padconf_set - sets the muxmode and state for a pad/pin
176  *	@padname: the name of the pad, i.e. "c12"
177  *	@muxmode: the name of the mode to use for the pin, i.e. "uart1_rx"
178  *	@state: the state to put the pad/pin in, i.e. PADCONF_PIN_???
179  *
180  *
181  *	LOCKING:
182  *	Internally locks it's own context.
183  *
184  *	RETURNS:
185  *	0 on success.
186  *	EINVAL if pin requested is outside valid range or already in use.
187  */
188 int
189 ti_scm_padconf_set(const char *padname, const char *muxmode, unsigned int state)
190 {
191 	const struct ti_scm_padconf *padconf;
192 
193 	if (!ti_scm_sc)
194 		return (ENXIO);
195 
196 	/* find the pin in the devmap */
197 	padconf = ti_scm_padconf_from_name(padname);
198 	if (padconf == NULL)
199 		return (EINVAL);
200 
201 	return (ti_scm_padconf_set_internal(ti_scm_sc, padconf, muxmode, state));
202 }
203 
204 /**
205  *	ti_scm_padconf_get - gets the muxmode and state for a pad/pin
206  *	@padname: the name of the pad, i.e. "c12"
207  *	@muxmode: upon return will contain the name of the muxmode of the pin
208  *	@state: upon return will contain the state of the pad/pin
209  *
210  *
211  *	LOCKING:
212  *	Internally locks it's own context.
213  *
214  *	RETURNS:
215  *	0 on success.
216  *	EINVAL if pin requested is outside valid range or already in use.
217  */
218 int
219 ti_scm_padconf_get(const char *padname, const char **muxmode,
220     unsigned int *state)
221 {
222 	const struct ti_scm_padconf *padconf;
223 	uint16_t reg_val;
224 
225 	if (!ti_scm_sc)
226 		return (ENXIO);
227 
228 	/* find the pin in the devmap */
229 	padconf = ti_scm_padconf_from_name(padname);
230 	if (padconf == NULL)
231 		return (EINVAL);
232 
233 	/* read the register value (16-bit reads) */
234 	reg_val = ti_scm_read_2(ti_scm_sc, padconf->reg_off);
235 
236 	/* save the state */
237 	if (state)
238 		*state = (reg_val & ti_scm_dev.padconf_sate_mask);
239 
240 	/* save the mode */
241 	if (muxmode)
242 		*muxmode = padconf->muxmodes[(reg_val & ti_scm_dev.padconf_muxmode_mask)];
243 
244 	return (0);
245 }
246 
247 /**
248  *	ti_scm_padconf_set_gpiomode - converts a pad to GPIO mode.
249  *	@gpio: the GPIO pin number (0-195)
250  *	@state: the state to put the pad/pin in, i.e. PADCONF_PIN_???
251  *
252  *
253  *
254  *	LOCKING:
255  *	Internally locks it's own context.
256  *
257  *	RETURNS:
258  *	0 on success.
259  *	EINVAL if pin requested is outside valid range or already in use.
260  */
261 int
262 ti_scm_padconf_set_gpiomode(uint32_t gpio, unsigned int state)
263 {
264 	const struct ti_scm_padconf *padconf;
265 	uint16_t reg_val;
266 
267 	if (!ti_scm_sc)
268 		return (ENXIO);
269 
270 	/* find the gpio pin in the padconf array */
271 	padconf = ti_scm_dev.padconf;
272 	while (padconf->ballname != NULL) {
273 		if (padconf->gpio_pin == gpio)
274 			break;
275 		padconf++;
276 	}
277 	if (padconf->ballname == NULL)
278 		return (EINVAL);
279 
280 	/* populate the new value for the PADCONF register */
281 	reg_val = (uint16_t)(state & ti_scm_dev.padconf_sate_mask);
282 
283 	/* set the mux mode */
284 	reg_val |= (uint16_t)(padconf->gpio_mode & ti_scm_dev.padconf_muxmode_mask);
285 
286 	/* write the register value (16-bit writes) */
287 	ti_scm_write_2(ti_scm_sc, padconf->reg_off, reg_val);
288 
289 	return (0);
290 }
291 
292 /**
293  *	ti_scm_padconf_get_gpiomode - gets the current GPIO mode of the pin
294  *	@gpio: the GPIO pin number (0-195)
295  *	@state: upon return will contain the state
296  *
297  *
298  *
299  *	LOCKING:
300  *	Internally locks it's own context.
301  *
302  *	RETURNS:
303  *	0 on success.
304  *	EINVAL if pin requested is outside valid range or not configured as GPIO.
305  */
306 int
307 ti_scm_padconf_get_gpiomode(uint32_t gpio, unsigned int *state)
308 {
309 	const struct ti_scm_padconf *padconf;
310 	uint16_t reg_val;
311 
312 	if (!ti_scm_sc)
313 		return (ENXIO);
314 
315 	/* find the gpio pin in the padconf array */
316 	padconf = ti_scm_dev.padconf;
317 	while (padconf->ballname != NULL) {
318 		if (padconf->gpio_pin == gpio)
319 			break;
320 		padconf++;
321 	}
322 	if (padconf->ballname == NULL)
323 		return (EINVAL);
324 
325 	/* read the current register settings */
326 	reg_val = ti_scm_read_2(ti_scm_sc, padconf->reg_off);
327 
328 	/* check to make sure the pins is configured as GPIO in the first state */
329 	if ((reg_val & ti_scm_dev.padconf_muxmode_mask) != padconf->gpio_mode)
330 		return (EINVAL);
331 
332 	/* read and store the reset of the state, i.e. pull-up, pull-down, etc */
333 	if (state)
334 		*state = (reg_val & ti_scm_dev.padconf_sate_mask);
335 
336 	return (0);
337 }
338 
339 /**
340  *	ti_scm_padconf_init_from_hints - processes the hints for padconf
341  *	@sc: the driver soft context
342  *
343  *
344  *
345  *	LOCKING:
346  *	Internally locks it's own context.
347  *
348  *	RETURNS:
349  *	0 on success.
350  *	EINVAL if pin requested is outside valid range or already in use.
351  */
352 static int
353 ti_scm_padconf_init_from_fdt(struct ti_scm_softc *sc)
354 {
355 	const struct ti_scm_padconf *padconf;
356 	const struct ti_scm_padstate *padstates;
357 	int err;
358 	phandle_t node;
359 	int len;
360 	char *fdt_pad_config;
361 	int i;
362 	char *padname, *muxname, *padstate;
363 
364 	node = ofw_bus_get_node(sc->sc_dev);
365 	len = OF_getproplen(node, "scm-pad-config");
366         OF_getprop_alloc(node, "scm-pad-config", 1, (void **)&fdt_pad_config);
367 
368 	i = len;
369 	while (i > 0) {
370 		padname = fdt_pad_config;
371 		fdt_pad_config += strlen(padname) + 1;
372 		i -= strlen(padname) + 1;
373 		if (i <= 0)
374 			break;
375 
376 		muxname = fdt_pad_config;
377 		fdt_pad_config += strlen(muxname) + 1;
378 		i -= strlen(muxname) + 1;
379 		if (i <= 0)
380 			break;
381 
382 		padstate = fdt_pad_config;
383 		fdt_pad_config += strlen(padstate) + 1;
384 		i -= strlen(padstate) + 1;
385 		if (i < 0)
386 			break;
387 
388 		padconf = ti_scm_dev.padconf;
389 
390 		while (padconf->ballname != NULL) {
391 			if (strcmp(padconf->ballname, padname) == 0) {
392 				padstates = ti_scm_dev.padstate;
393 				err = 1;
394 				while (padstates->state != NULL) {
395 					if (strcmp(padstates->state, padstate) == 0) {
396 						err = ti_scm_padconf_set_internal(sc,
397 						    padconf, muxname, padstates->reg);
398 					}
399 					padstates++;
400 				}
401 				if (err)
402 					device_printf(sc->sc_dev,
403 					    "err: failed to configure "
404 					    "pin \"%s\" as \"%s\"\n",
405 					    padconf->ballname,
406 					    muxname);
407 			}
408 			padconf++;
409 		}
410 	}
411 	return (0);
412 }
413 
414 /*
415  * Device part of OMAP SCM driver
416  */
417 
418 static int
419 ti_scm_probe(device_t dev)
420 {
421 	if (!ofw_bus_is_compatible(dev, "ti,scm"))
422 		return (ENXIO);
423 
424 	device_set_desc(dev, "TI Control Module");
425 	return (BUS_PROBE_DEFAULT);
426 }
427 
428 /**
429  *	ti_scm_attach - attaches the timer to the simplebus
430  *	@dev: new device
431  *
432  *	Reserves memory and interrupt resources, stores the softc structure
433  *	globally and registers both the timecount and eventtimer objects.
434  *
435  *	RETURNS
436  *	Zero on sucess or ENXIO if an error occuried.
437  */
438 static int
439 ti_scm_attach(device_t dev)
440 {
441 	struct ti_scm_softc *sc = device_get_softc(dev);
442 
443 	if (ti_scm_sc)
444 		return (ENXIO);
445 
446 	sc->sc_dev = dev;
447 
448 	if (bus_alloc_resources(dev, ti_scm_res_spec, sc->sc_res)) {
449 		device_printf(dev, "could not allocate resources\n");
450 		return (ENXIO);
451 	}
452 
453 	/* Global timer interface */
454 	sc->sc_bst = rman_get_bustag(sc->sc_res[0]);
455 	sc->sc_bsh = rman_get_bushandle(sc->sc_res[0]);
456 
457 	ti_scm_sc = sc;
458 
459 	ti_scm_padconf_init_from_fdt(sc);
460 
461 	return (0);
462 }
463 
464 int
465 ti_scm_reg_read_4(uint32_t reg, uint32_t *val)
466 {
467 	if (!ti_scm_sc)
468 		return (ENXIO);
469 
470 	*val = ti_scm_read_4(ti_scm_sc, reg);
471 	return (0);
472 }
473 
474 int
475 ti_scm_reg_write_4(uint32_t reg, uint32_t val)
476 {
477 	if (!ti_scm_sc)
478 		return (ENXIO);
479 
480 	ti_scm_write_4(ti_scm_sc, reg, val);
481 	return (0);
482 }
483 
484 
485 static device_method_t ti_scm_methods[] = {
486 	DEVMETHOD(device_probe,		ti_scm_probe),
487 	DEVMETHOD(device_attach,	ti_scm_attach),
488 	{ 0, 0 }
489 };
490 
491 static driver_t ti_scm_driver = {
492 	"ti_scm",
493 	ti_scm_methods,
494 	sizeof(struct ti_scm_softc),
495 };
496 
497 static devclass_t ti_scm_devclass;
498 
499 DRIVER_MODULE(ti_scm, simplebus, ti_scm_driver, ti_scm_devclass, 0, 0);
500