xref: /freebsd/sys/powerpc/cpufreq/mpc85xx_jog.c (revision 8df8b2d3e51d1b816201d8a1fe8bc29fe192e562)
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 
92 	{0, 0}
93 };
94 
95 static driver_t mpc85xx_jog_driver = {
96 	"jog",
97 	mpc85xx_jog_methods,
98 	sizeof(struct mpc85xx_jog_softc)
99 };
100 
101 static devclass_t mpc85xx_jog_devclass;
102 DRIVER_MODULE(mpc85xx_jog, cpu, mpc85xx_jog_driver, mpc85xx_jog_devclass, 0, 0);
103 
104 struct mpc85xx_constraints {
105 	int threshold; /* Threshold frequency, in MHz, for setting CORE_SPD bit. */
106 	int min_mult;  /* Minimum PLL multiplier. */
107 };
108 
109 static struct mpc85xx_constraints mpc8536_constraints = {
110 	800,
111 	3
112 };
113 
114 static struct mpc85xx_constraints p1022_constraints = {
115 	500,
116 	2
117 };
118 
119 static struct ofw_compat_data jog_compat[] = {
120     {"fsl,mpc8536-guts", (uintptr_t)&mpc8536_constraints},
121     {"fsl,p1022-guts", (uintptr_t)&p1022_constraints},
122     {NULL, 0}
123 };
124 
125 static struct ofw_compat_data *
126 mpc85xx_jog_devcompat()
127 {
128 	phandle_t node;
129 	int i;
130 
131 	node = OF_finddevice("/soc");
132 	if (node == -1)
133 		return (NULL);
134 
135 	for (i = 0; jog_compat[i].ocd_str != NULL; i++)
136 		if (ofw_bus_find_compatible(node, jog_compat[i].ocd_str) > 0)
137 			break;
138 
139 	if (jog_compat[i].ocd_str == NULL)
140 		return (NULL);
141 
142 	return (&jog_compat[i]);
143 }
144 
145 static void
146 mpc85xx_jog_identify(driver_t *driver, device_t parent)
147 {
148 	struct ofw_compat_data *compat;
149 
150 	/* Make sure we're not being doubly invoked. */
151 	if (device_find_child(parent, "mpc85xx_jog", -1) != NULL)
152 		return;
153 
154 	compat = mpc85xx_jog_devcompat();
155 	if (compat == NULL)
156 		return;
157 
158 	/*
159 	 * We attach a child for every CPU since settings need to
160 	 * be performed on every CPU in the SMP case.
161 	 */
162 	if (BUS_ADD_CHILD(parent, 10, "jog", -1) == NULL)
163 		device_printf(parent, "add jog child failed\n");
164 }
165 
166 static int
167 mpc85xx_jog_probe(device_t dev)
168 {
169 	struct ofw_compat_data *compat;
170 
171 	compat = mpc85xx_jog_devcompat();
172 	if (compat == NULL || compat->ocd_str == NULL)
173 		return (ENXIO);
174 
175 	device_set_desc(dev, "Freescale CPU Jogger");
176 	return (0);
177 }
178 
179 static int
180 mpc85xx_jog_attach(device_t dev)
181 {
182 	struct ofw_compat_data *compat;
183 	struct mpc85xx_jog_softc *sc;
184 	struct mpc85xx_constraints *constraints;
185 	phandle_t cpu;
186 	uint32_t reg;
187 
188 	sc = device_get_softc(dev);
189 	sc->dev = dev;
190 
191 	compat = mpc85xx_jog_devcompat();
192 	constraints = (struct mpc85xx_constraints *)compat->ocd_data;
193 	cpu = ofw_bus_get_node(device_get_parent(dev));
194 
195 	if (cpu <= 0) {
196 		device_printf(dev,"No CPU device tree node!\n");
197 		return (ENXIO);
198 	}
199 
200 	OF_getencprop(cpu, "reg", &sc->cpu, sizeof(sc->cpu));
201 
202 	reg = ccsr_read4(GUTS_PORPLLSR);
203 
204 	/*
205 	 * Assume power-on PLL is the highest PLL config supported on the
206 	 * board.
207 	 */
208 	sc->high = PMJCR_GET_CORE_MULT(reg, sc->cpu);
209 	sc->min_freq = constraints->threshold;
210 	sc->low = constraints->min_mult;
211 
212 	cpufreq_register(dev);
213 	return (0);
214 }
215 
216 static int
217 mpc85xx_jog_settings(device_t dev, struct cf_setting *sets, int *count)
218 {
219 	struct mpc85xx_jog_softc *sc;
220 	uint32_t sysclk;
221 	int i;
222 
223 	sc = device_get_softc(dev);
224 	if (sets == NULL || count == NULL)
225 		return (EINVAL);
226 	if (*count < sc->high - 1)
227 		return (E2BIG);
228 
229 	sysclk = mpc85xx_get_system_clock();
230 	/* Return a list of valid settings for this driver. */
231 	memset(sets, CPUFREQ_VAL_UNKNOWN, sizeof(*sets) * sc->high);
232 
233 	for (i = sc->high; i >= sc->low; --i) {
234 		sets[sc->high - i].freq = sysclk * i / MHZ;
235 		sets[sc->high - i].dev = dev;
236 		sets[sc->high - i].spec[0] = i;
237 	}
238 	*count = sc->high - sc->low + 1;
239 
240 	return (0);
241 }
242 
243 struct jog_rv_args {
244 	int cpu;
245 	int mult;
246 	int slow;
247 	volatile int inprogress;
248 };
249 
250 static void
251 mpc85xx_jog_set_int(void *arg)
252 {
253 	struct jog_rv_args *args = arg;
254 	uint32_t reg;
255 
256 	if (PCPU_GET(cpuid) == args->cpu) {
257 		reg = ccsr_read4(GUTS_PMJCR);
258 		reg &= ~PMJCR_CORE_MULT(PMJCR_RATIO_M, args->cpu);
259 		reg |= PMJCR_CORE_MULT(args->mult, args->cpu);
260 		if (args->slow)
261 			reg &= ~(1 << (12 + args->cpu));
262 		else
263 			reg |= (1 << (12 + args->cpu));
264 
265 		ccsr_write4(GUTS_PMJCR, reg);
266 
267 		reg = ccsr_read4(GUTS_POWMGTCSR);
268 		reg |= POWMGTCSR_JOG | POWMGTCSR_INT_MASK;
269 		ccsr_write4(GUTS_POWMGTCSR, reg);
270 
271 		/* Wait for completion */
272 		do {
273 			DELAY(100);
274 			reg = ccsr_read4(GUTS_POWMGTCSR);
275 		} while (reg & POWMGTCSR_JOG);
276 
277 		reg = ccsr_read4(GUTS_POWMGTCSR);
278 		ccsr_write4(GUTS_POWMGTCSR, reg & ~POWMGTCSR_INT_MASK);
279 		ccsr_read4(GUTS_POWMGTCSR);
280 
281 		args->inprogress = 0;
282 	} else {
283 		while (args->inprogress)
284 			cpu_spinwait();
285 	}
286 }
287 
288 static int
289 mpc85xx_jog_set(device_t dev, const struct cf_setting *set)
290 {
291 	struct mpc85xx_jog_softc *sc;
292 	struct jog_rv_args args;
293 
294 	if (set == NULL)
295 		return (EINVAL);
296 
297 	sc = device_get_softc(dev);
298 
299 	args.slow = (set->freq <= sc->min_freq);
300 	args.mult = set->spec[0];
301 	args.cpu = PCPU_GET(cpuid);
302 	args.inprogress = 1;
303 	smp_rendezvous(smp_no_rendezvous_barrier, mpc85xx_jog_set_int,
304 	    smp_no_rendezvous_barrier, &args);
305 
306 	return (0);
307 }
308 
309 static int
310 mpc85xx_jog_get(device_t dev, struct cf_setting *set)
311 {
312 	struct mpc85xx_jog_softc *sc;
313 	uint32_t pmjcr;
314 	uint32_t freq;
315 
316 	if (set == NULL)
317 		return (EINVAL);
318 
319 	sc = device_get_softc(dev);
320 	memset(set, CPUFREQ_VAL_UNKNOWN, sizeof(*set));
321 
322 	pmjcr = ccsr_read4(GUTS_PORPLLSR);
323 	freq = PMJCR_GET_CORE_MULT(pmjcr, sc->cpu);
324 	freq *= mpc85xx_get_system_clock();
325 	freq /= MHZ;
326 
327 	set->freq = freq;
328 	set->dev = dev;
329 
330 	return (0);
331 }
332 
333 static int
334 mpc85xx_jog_type(device_t dev, int *type)
335 {
336 
337 	if (type == NULL)
338 		return (EINVAL);
339 
340 	*type = CPUFREQ_TYPE_ABSOLUTE;
341 	return (0);
342 }
343 
344