xref: /openbmc/linux/arch/arm/mach-omap2/pm.c (revision d0b73b48)
1 /*
2  * pm.c - Common OMAP2+ power management-related code
3  *
4  * Copyright (C) 2010 Texas Instruments, Inc.
5  * Copyright (C) 2010 Nokia Corporation
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/init.h>
14 #include <linux/io.h>
15 #include <linux/err.h>
16 #include <linux/opp.h>
17 #include <linux/export.h>
18 #include <linux/suspend.h>
19 #include <linux/cpu.h>
20 
21 #include <asm/system_misc.h>
22 
23 #include "omap-pm.h"
24 #include "omap_device.h"
25 #include "common.h"
26 
27 #include "soc.h"
28 #include "prcm-common.h"
29 #include "voltage.h"
30 #include "powerdomain.h"
31 #include "clockdomain.h"
32 #include "pm.h"
33 #include "twl-common.h"
34 
35 static struct omap_device_pm_latency *pm_lats;
36 
37 /*
38  * omap_pm_suspend: points to a function that does the SoC-specific
39  * suspend work
40  */
41 int (*omap_pm_suspend)(void);
42 
43 #ifdef CONFIG_PM
44 /**
45  * struct omap2_oscillator - Describe the board main oscillator latencies
46  * @startup_time: oscillator startup latency
47  * @shutdown_time: oscillator shutdown latency
48  */
49 struct omap2_oscillator {
50 	u32 startup_time;
51 	u32 shutdown_time;
52 };
53 
54 static struct omap2_oscillator oscillator = {
55 	.startup_time = ULONG_MAX,
56 	.shutdown_time = ULONG_MAX,
57 };
58 
59 void omap_pm_setup_oscillator(u32 tstart, u32 tshut)
60 {
61 	oscillator.startup_time = tstart;
62 	oscillator.shutdown_time = tshut;
63 }
64 
65 void omap_pm_get_oscillator(u32 *tstart, u32 *tshut)
66 {
67 	if (!tstart || !tshut)
68 		return;
69 
70 	*tstart = oscillator.startup_time;
71 	*tshut = oscillator.shutdown_time;
72 }
73 #endif
74 
75 static int __init _init_omap_device(char *name)
76 {
77 	struct omap_hwmod *oh;
78 	struct platform_device *pdev;
79 
80 	oh = omap_hwmod_lookup(name);
81 	if (WARN(!oh, "%s: could not find omap_hwmod for %s\n",
82 		 __func__, name))
83 		return -ENODEV;
84 
85 	pdev = omap_device_build(oh->name, 0, oh, NULL, 0, pm_lats, 0, false);
86 	if (WARN(IS_ERR(pdev), "%s: could not build omap_device for %s\n",
87 		 __func__, name))
88 		return -ENODEV;
89 
90 	return 0;
91 }
92 
93 /*
94  * Build omap_devices for processors and bus.
95  */
96 static void __init omap2_init_processor_devices(void)
97 {
98 	_init_omap_device("mpu");
99 	if (omap3_has_iva())
100 		_init_omap_device("iva");
101 
102 	if (cpu_is_omap44xx()) {
103 		_init_omap_device("l3_main_1");
104 		_init_omap_device("dsp");
105 		_init_omap_device("iva");
106 	} else {
107 		_init_omap_device("l3_main");
108 	}
109 }
110 
111 /* Types of sleep_switch used in omap_set_pwrdm_state */
112 #define FORCEWAKEUP_SWITCH	0
113 #define LOWPOWERSTATE_SWITCH	1
114 
115 int __init omap_pm_clkdms_setup(struct clockdomain *clkdm, void *unused)
116 {
117 	if ((clkdm->flags & CLKDM_CAN_ENABLE_AUTO) &&
118 	    !(clkdm->flags & CLKDM_MISSING_IDLE_REPORTING))
119 		clkdm_allow_idle(clkdm);
120 	else if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP &&
121 		 atomic_read(&clkdm->usecount) == 0)
122 		clkdm_sleep(clkdm);
123 	return 0;
124 }
125 
126 /*
127  * This sets pwrdm state (other than mpu & core. Currently only ON &
128  * RET are supported.
129  */
130 int omap_set_pwrdm_state(struct powerdomain *pwrdm, u32 pwrst)
131 {
132 	u8 curr_pwrst, next_pwrst;
133 	int sleep_switch = -1, ret = 0, hwsup = 0;
134 
135 	if (!pwrdm || IS_ERR(pwrdm))
136 		return -EINVAL;
137 
138 	while (!(pwrdm->pwrsts & (1 << pwrst))) {
139 		if (pwrst == PWRDM_POWER_OFF)
140 			return ret;
141 		pwrst--;
142 	}
143 
144 	next_pwrst = pwrdm_read_next_pwrst(pwrdm);
145 	if (next_pwrst == pwrst)
146 		return ret;
147 
148 	curr_pwrst = pwrdm_read_pwrst(pwrdm);
149 	if (curr_pwrst < PWRDM_POWER_ON) {
150 		if ((curr_pwrst > pwrst) &&
151 			(pwrdm->flags & PWRDM_HAS_LOWPOWERSTATECHANGE)) {
152 			sleep_switch = LOWPOWERSTATE_SWITCH;
153 		} else {
154 			hwsup = clkdm_in_hwsup(pwrdm->pwrdm_clkdms[0]);
155 			clkdm_wakeup(pwrdm->pwrdm_clkdms[0]);
156 			sleep_switch = FORCEWAKEUP_SWITCH;
157 		}
158 	}
159 
160 	ret = pwrdm_set_next_pwrst(pwrdm, pwrst);
161 	if (ret)
162 		pr_err("%s: unable to set power state of powerdomain: %s\n",
163 		       __func__, pwrdm->name);
164 
165 	switch (sleep_switch) {
166 	case FORCEWAKEUP_SWITCH:
167 		if (hwsup)
168 			clkdm_allow_idle(pwrdm->pwrdm_clkdms[0]);
169 		else
170 			clkdm_sleep(pwrdm->pwrdm_clkdms[0]);
171 		break;
172 	case LOWPOWERSTATE_SWITCH:
173 		pwrdm_set_lowpwrstchange(pwrdm);
174 		pwrdm_wait_transition(pwrdm);
175 		pwrdm_state_switch(pwrdm);
176 		break;
177 	}
178 
179 	return ret;
180 }
181 
182 
183 
184 /*
185  * This API is to be called during init to set the various voltage
186  * domains to the voltage as per the opp table. Typically we boot up
187  * at the nominal voltage. So this function finds out the rate of
188  * the clock associated with the voltage domain, finds out the correct
189  * opp entry and sets the voltage domain to the voltage specified
190  * in the opp entry
191  */
192 static int __init omap2_set_init_voltage(char *vdd_name, char *clk_name,
193 					 const char *oh_name)
194 {
195 	struct voltagedomain *voltdm;
196 	struct clk *clk;
197 	struct opp *opp;
198 	unsigned long freq, bootup_volt;
199 	struct device *dev;
200 
201 	if (!vdd_name || !clk_name || !oh_name) {
202 		pr_err("%s: invalid parameters\n", __func__);
203 		goto exit;
204 	}
205 
206 	if (!strncmp(oh_name, "mpu", 3))
207 		/*
208 		 * All current OMAPs share voltage rail and clock
209 		 * source, so CPU0 is used to represent the MPU-SS.
210 		 */
211 		dev = get_cpu_device(0);
212 	else
213 		dev = omap_device_get_by_hwmod_name(oh_name);
214 
215 	if (IS_ERR(dev)) {
216 		pr_err("%s: Unable to get dev pointer for hwmod %s\n",
217 			__func__, oh_name);
218 		goto exit;
219 	}
220 
221 	voltdm = voltdm_lookup(vdd_name);
222 	if (!voltdm) {
223 		pr_err("%s: unable to get vdd pointer for vdd_%s\n",
224 			__func__, vdd_name);
225 		goto exit;
226 	}
227 
228 	clk =  clk_get(NULL, clk_name);
229 	if (IS_ERR(clk)) {
230 		pr_err("%s: unable to get clk %s\n", __func__, clk_name);
231 		goto exit;
232 	}
233 
234 	freq = clk_get_rate(clk);
235 	clk_put(clk);
236 
237 	rcu_read_lock();
238 	opp = opp_find_freq_ceil(dev, &freq);
239 	if (IS_ERR(opp)) {
240 		rcu_read_unlock();
241 		pr_err("%s: unable to find boot up OPP for vdd_%s\n",
242 			__func__, vdd_name);
243 		goto exit;
244 	}
245 
246 	bootup_volt = opp_get_voltage(opp);
247 	rcu_read_unlock();
248 	if (!bootup_volt) {
249 		pr_err("%s: unable to find voltage corresponding to the bootup OPP for vdd_%s\n",
250 		       __func__, vdd_name);
251 		goto exit;
252 	}
253 
254 	voltdm_scale(voltdm, bootup_volt);
255 	return 0;
256 
257 exit:
258 	pr_err("%s: unable to set vdd_%s\n", __func__, vdd_name);
259 	return -EINVAL;
260 }
261 
262 #ifdef CONFIG_SUSPEND
263 static int omap_pm_enter(suspend_state_t suspend_state)
264 {
265 	int ret = 0;
266 
267 	if (!omap_pm_suspend)
268 		return -ENOENT; /* XXX doublecheck */
269 
270 	switch (suspend_state) {
271 	case PM_SUSPEND_STANDBY:
272 	case PM_SUSPEND_MEM:
273 		ret = omap_pm_suspend();
274 		break;
275 	default:
276 		ret = -EINVAL;
277 	}
278 
279 	return ret;
280 }
281 
282 static int omap_pm_begin(suspend_state_t state)
283 {
284 	disable_hlt();
285 	if (cpu_is_omap34xx())
286 		omap_prcm_irq_prepare();
287 	return 0;
288 }
289 
290 static void omap_pm_end(void)
291 {
292 	enable_hlt();
293 	return;
294 }
295 
296 static void omap_pm_finish(void)
297 {
298 	if (cpu_is_omap34xx())
299 		omap_prcm_irq_complete();
300 }
301 
302 static const struct platform_suspend_ops omap_pm_ops = {
303 	.begin		= omap_pm_begin,
304 	.end		= omap_pm_end,
305 	.enter		= omap_pm_enter,
306 	.finish		= omap_pm_finish,
307 	.valid		= suspend_valid_only_mem,
308 };
309 
310 #endif /* CONFIG_SUSPEND */
311 
312 static void __init omap3_init_voltages(void)
313 {
314 	if (!cpu_is_omap34xx())
315 		return;
316 
317 	omap2_set_init_voltage("mpu_iva", "dpll1_ck", "mpu");
318 	omap2_set_init_voltage("core", "l3_ick", "l3_main");
319 }
320 
321 static void __init omap4_init_voltages(void)
322 {
323 	if (!cpu_is_omap44xx())
324 		return;
325 
326 	omap2_set_init_voltage("mpu", "dpll_mpu_ck", "mpu");
327 	omap2_set_init_voltage("core", "l3_div_ck", "l3_main_1");
328 	omap2_set_init_voltage("iva", "dpll_iva_m5x2_ck", "iva");
329 }
330 
331 static int __init omap2_common_pm_init(void)
332 {
333 	if (!of_have_populated_dt())
334 		omap2_init_processor_devices();
335 	omap_pm_if_init();
336 
337 	return 0;
338 }
339 postcore_initcall(omap2_common_pm_init);
340 
341 int __init omap2_common_pm_late_init(void)
342 {
343 	/*
344 	 * In the case of DT, the PMIC and SR initialization will be done using
345 	 * a completely different mechanism.
346 	 * Disable this part if a DT blob is available.
347 	 */
348 	if (of_have_populated_dt())
349 		return 0;
350 
351 	/* Init the voltage layer */
352 	omap_pmic_late_init();
353 	omap_voltage_late_init();
354 
355 	/* Initialize the voltages */
356 	omap3_init_voltages();
357 	omap4_init_voltages();
358 
359 	/* Smartreflex device init */
360 	omap_devinit_smartreflex();
361 
362 #ifdef CONFIG_SUSPEND
363 	suspend_set_ops(&omap_pm_ops);
364 #endif
365 
366 	return 0;
367 }
368