xref: /freebsd/sys/powerpc/cpufreq/mpc85xx_jog.c (revision f7c32ed617858bcd22f8d1b03199099d50125721)
1 /*-
2  * Copyright (c) 2017 Justin Hibbits
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
19  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
20  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
21  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
22  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/cpu.h>
34 #include <sys/kernel.h>
35 #include <sys/module.h>
36 #include <sys/smp.h>
37 
38 #include <dev/ofw/ofw_bus.h>
39 #include <dev/ofw/ofw_bus_subr.h>
40 
41 #include <machine/cpu.h>
42 
43 #include <powerpc/mpc85xx/mpc85xx.h>
44 
45 #include "cpufreq_if.h"
46 
47 /* No worries about uint32_t math overflow in here, because the highest
48  * multiplier supported is 4, and the highest speed part is still well below
49  * 2GHz.
50  */
51 
52 #define	GUTS_PORPLLSR		(CCSRBAR_VA + 0xe0000)
53 #define	GUTS_PMJCR		(CCSRBAR_VA + 0xe007c)
54 #define	  PMJCR_RATIO_M		  0x3f
55 #define	  PMJCR_CORE_MULT(x,y)	  ((x) << (16 + ((y) * 8)))
56 #define	  PMJCR_GET_CORE_MULT(x,y)	  (((x) >> (16 + ((y) * 8))) & 0x3f)
57 #define	GUTS_POWMGTCSR		(CCSRBAR_VA + 0xe0080)
58 #define	  POWMGTCSR_JOG		  0x00200000
59 #define	  POWMGTCSR_INT_MASK	  0x00000f00
60 
61 #define	MHZ	1000000
62 
63 struct mpc85xx_jog_softc {
64 	device_t dev;
65 	int	cpu;
66 	int	low;
67 	int	high;
68 	int	min_freq;
69 };
70 
71 static struct ofw_compat_data *mpc85xx_jog_devcompat(void);
72 static void	mpc85xx_jog_identify(driver_t *driver, device_t parent);
73 static int	mpc85xx_jog_probe(device_t dev);
74 static int	mpc85xx_jog_attach(device_t dev);
75 static int	mpc85xx_jog_settings(device_t dev, struct cf_setting *sets, int *count);
76 static int	mpc85xx_jog_set(device_t dev, const struct cf_setting *set);
77 static int	mpc85xx_jog_get(device_t dev, struct cf_setting *set);
78 static int	mpc85xx_jog_type(device_t dev, int *type);
79 
80 static device_method_t mpc85xx_jog_methods[] = {
81 	/* Device interface */
82 	DEVMETHOD(device_identify,	mpc85xx_jog_identify),
83 	DEVMETHOD(device_probe,		mpc85xx_jog_probe),
84 	DEVMETHOD(device_attach,	mpc85xx_jog_attach),
85 
86 	/* cpufreq interface */
87 	DEVMETHOD(cpufreq_drv_set,	mpc85xx_jog_set),
88 	DEVMETHOD(cpufreq_drv_get,	mpc85xx_jog_get),
89 	DEVMETHOD(cpufreq_drv_type,	mpc85xx_jog_type),
90 	DEVMETHOD(cpufreq_drv_settings,	mpc85xx_jog_settings),
91 	{0, 0}
92 };
93 
94 static driver_t mpc85xx_jog_driver = {
95 	"jog",
96 	mpc85xx_jog_methods,
97 	sizeof(struct mpc85xx_jog_softc)
98 };
99 
100 static devclass_t mpc85xx_jog_devclass;
101 DRIVER_MODULE(mpc85xx_jog, cpu, mpc85xx_jog_driver, mpc85xx_jog_devclass, 0, 0);
102 
103 struct mpc85xx_constraints {
104 	int threshold; /* Threshold frequency, in MHz, for setting CORE_SPD bit. */
105 	int min_mult;  /* Minimum PLL multiplier. */
106 };
107 
108 static struct mpc85xx_constraints mpc8536_constraints = {
109 	800,
110 	3
111 };
112 
113 static struct mpc85xx_constraints p1022_constraints = {
114 	500,
115 	2
116 };
117 
118 static struct ofw_compat_data jog_compat[] = {
119     {"fsl,mpc8536-guts", (uintptr_t)&mpc8536_constraints},
120     {"fsl,p1022-guts", (uintptr_t)&p1022_constraints},
121     {NULL, 0}
122 };
123 
124 static struct ofw_compat_data *
125 mpc85xx_jog_devcompat()
126 {
127 	phandle_t node;
128 	int i;
129 
130 	node = OF_finddevice("/soc");
131 	if (node == -1)
132 		return (NULL);
133 
134 	for (i = 0; jog_compat[i].ocd_str != NULL; i++)
135 		if (ofw_bus_find_compatible(node, jog_compat[i].ocd_str) > 0)
136 			break;
137 
138 	if (jog_compat[i].ocd_str == NULL)
139 		return (NULL);
140 
141 	return (&jog_compat[i]);
142 }
143 
144 static void
145 mpc85xx_jog_identify(driver_t *driver, device_t parent)
146 {
147 	struct ofw_compat_data *compat;
148 
149 	/* Make sure we're not being doubly invoked. */
150 	if (device_find_child(parent, "mpc85xx_jog", -1) != NULL)
151 		return;
152 
153 	compat = mpc85xx_jog_devcompat();
154 	if (compat == NULL)
155 		return;
156 
157 	/*
158 	 * We attach a child for every CPU since settings need to
159 	 * be performed on every CPU in the SMP case.
160 	 */
161 	if (BUS_ADD_CHILD(parent, 10, "jog", -1) == NULL)
162 		device_printf(parent, "add jog child failed\n");
163 }
164 
165 static int
166 mpc85xx_jog_probe(device_t dev)
167 {
168 	struct ofw_compat_data *compat;
169 
170 	compat = mpc85xx_jog_devcompat();
171 	if (compat == NULL || compat->ocd_str == NULL)
172 		return (ENXIO);
173 
174 	device_set_desc(dev, "Freescale CPU Jogger");
175 	return (0);
176 }
177 
178 static int
179 mpc85xx_jog_attach(device_t dev)
180 {
181 	struct ofw_compat_data *compat;
182 	struct mpc85xx_jog_softc *sc;
183 	struct mpc85xx_constraints *constraints;
184 	phandle_t cpu;
185 	uint32_t reg;
186 
187 	sc = device_get_softc(dev);
188 	sc->dev = dev;
189 
190 	compat = mpc85xx_jog_devcompat();
191 	constraints = (struct mpc85xx_constraints *)compat->ocd_data;
192 	cpu = ofw_bus_get_node(device_get_parent(dev));
193 
194 	if (cpu <= 0) {
195 		device_printf(dev,"No CPU device tree node!\n");
196 		return (ENXIO);
197 	}
198 
199 	OF_getencprop(cpu, "reg", &sc->cpu, sizeof(sc->cpu));
200 
201 	reg = ccsr_read4(GUTS_PORPLLSR);
202 
203 	/*
204 	 * Assume power-on PLL is the highest PLL config supported on the
205 	 * board.
206 	 */
207 	sc->high = PMJCR_GET_CORE_MULT(reg, sc->cpu);
208 	sc->min_freq = constraints->threshold;
209 	sc->low = constraints->min_mult;
210 
211 	cpufreq_register(dev);
212 	return (0);
213 }
214 
215 static int
216 mpc85xx_jog_settings(device_t dev, struct cf_setting *sets, int *count)
217 {
218 	struct mpc85xx_jog_softc *sc;
219 	uint32_t sysclk;
220 	int i;
221 
222 	sc = device_get_softc(dev);
223 	if (sets == NULL || count == NULL)
224 		return (EINVAL);
225 	if (*count < sc->high - 1)
226 		return (E2BIG);
227 
228 	sysclk = mpc85xx_get_system_clock();
229 	/* Return a list of valid settings for this driver. */
230 	memset(sets, CPUFREQ_VAL_UNKNOWN, sizeof(*sets) * sc->high);
231 
232 	for (i = sc->high; i >= sc->low; --i) {
233 		sets[sc->high - i].freq = sysclk * i / MHZ;
234 		sets[sc->high - i].dev = dev;
235 		sets[sc->high - i].spec[0] = i;
236 	}
237 	*count = sc->high - sc->low + 1;
238 
239 	return (0);
240 }
241 
242 struct jog_rv_args {
243 	int cpu;
244 	int mult;
245 	int slow;
246 	volatile int inprogress;
247 };
248 
249 static void
250 mpc85xx_jog_set_int(void *arg)
251 {
252 	struct jog_rv_args *args = arg;
253 	uint32_t reg;
254 
255 	if (PCPU_GET(cpuid) == args->cpu) {
256 		reg = ccsr_read4(GUTS_PMJCR);
257 		reg &= ~PMJCR_CORE_MULT(PMJCR_RATIO_M, args->cpu);
258 		reg |= PMJCR_CORE_MULT(args->mult, args->cpu);
259 		if (args->slow)
260 			reg &= ~(1 << (12 + args->cpu));
261 		else
262 			reg |= (1 << (12 + args->cpu));
263 
264 		ccsr_write4(GUTS_PMJCR, reg);
265 
266 		reg = ccsr_read4(GUTS_POWMGTCSR);
267 		reg |= POWMGTCSR_JOG | POWMGTCSR_INT_MASK;
268 		ccsr_write4(GUTS_POWMGTCSR, reg);
269 
270 		/* Wait for completion */
271 		do {
272 			DELAY(100);
273 			reg = ccsr_read4(GUTS_POWMGTCSR);
274 		} while (reg & POWMGTCSR_JOG);
275 
276 		reg = ccsr_read4(GUTS_POWMGTCSR);
277 		ccsr_write4(GUTS_POWMGTCSR, reg & ~POWMGTCSR_INT_MASK);
278 		ccsr_read4(GUTS_POWMGTCSR);
279 
280 		args->inprogress = 0;
281 	} else {
282 		while (args->inprogress)
283 			cpu_spinwait();
284 	}
285 }
286 
287 static int
288 mpc85xx_jog_set(device_t dev, const struct cf_setting *set)
289 {
290 	struct mpc85xx_jog_softc *sc;
291 	struct jog_rv_args args;
292 
293 	if (set == NULL)
294 		return (EINVAL);
295 
296 	sc = device_get_softc(dev);
297 
298 	args.slow = (set->freq <= sc->min_freq);
299 	args.mult = set->spec[0];
300 	args.cpu = PCPU_GET(cpuid);
301 	args.inprogress = 1;
302 	smp_rendezvous(smp_no_rendezvous_barrier, mpc85xx_jog_set_int,
303 	    smp_no_rendezvous_barrier, &args);
304 
305 	return (0);
306 }
307 
308 static int
309 mpc85xx_jog_get(device_t dev, struct cf_setting *set)
310 {
311 	struct mpc85xx_jog_softc *sc;
312 	uint32_t pmjcr;
313 	uint32_t freq;
314 
315 	if (set == NULL)
316 		return (EINVAL);
317 
318 	sc = device_get_softc(dev);
319 	memset(set, CPUFREQ_VAL_UNKNOWN, sizeof(*set));
320 
321 	pmjcr = ccsr_read4(GUTS_PORPLLSR);
322 	freq = PMJCR_GET_CORE_MULT(pmjcr, sc->cpu);
323 	freq *= mpc85xx_get_system_clock();
324 	freq /= MHZ;
325 
326 	set->freq = freq;
327 	set->dev = dev;
328 
329 	return (0);
330 }
331 
332 static int
333 mpc85xx_jog_type(device_t dev, int *type)
334 {
335 
336 	if (type == NULL)
337 		return (EINVAL);
338 
339 	*type = CPUFREQ_TYPE_ABSOLUTE;
340 	return (0);
341 }
342