xref: /openbmc/linux/arch/arm/mach-omap2/pm.c (revision 95e9fd10)
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 
20 #include <asm/system_misc.h>
21 
22 #include <plat/omap-pm.h>
23 #include <plat/omap_device.h>
24 #include "common.h"
25 
26 #include "prcm-common.h"
27 #include "voltage.h"
28 #include "powerdomain.h"
29 #include "clockdomain.h"
30 #include "pm.h"
31 #include "twl-common.h"
32 
33 static struct omap_device_pm_latency *pm_lats;
34 
35 /*
36  * omap_pm_suspend: points to a function that does the SoC-specific
37  * suspend work
38  */
39 int (*omap_pm_suspend)(void);
40 
41 static int __init _init_omap_device(char *name)
42 {
43 	struct omap_hwmod *oh;
44 	struct platform_device *pdev;
45 
46 	oh = omap_hwmod_lookup(name);
47 	if (WARN(!oh, "%s: could not find omap_hwmod for %s\n",
48 		 __func__, name))
49 		return -ENODEV;
50 
51 	pdev = omap_device_build(oh->name, 0, oh, NULL, 0, pm_lats, 0, false);
52 	if (WARN(IS_ERR(pdev), "%s: could not build omap_device for %s\n",
53 		 __func__, name))
54 		return -ENODEV;
55 
56 	return 0;
57 }
58 
59 /*
60  * Build omap_devices for processors and bus.
61  */
62 static void __init omap2_init_processor_devices(void)
63 {
64 	_init_omap_device("mpu");
65 	if (omap3_has_iva())
66 		_init_omap_device("iva");
67 
68 	if (cpu_is_omap44xx()) {
69 		_init_omap_device("l3_main_1");
70 		_init_omap_device("dsp");
71 		_init_omap_device("iva");
72 	} else {
73 		_init_omap_device("l3_main");
74 	}
75 }
76 
77 /* Types of sleep_switch used in omap_set_pwrdm_state */
78 #define FORCEWAKEUP_SWITCH	0
79 #define LOWPOWERSTATE_SWITCH	1
80 
81 int __init omap_pm_clkdms_setup(struct clockdomain *clkdm, void *unused)
82 {
83 	if (clkdm->flags & CLKDM_CAN_ENABLE_AUTO)
84 		clkdm_allow_idle(clkdm);
85 	else if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP &&
86 		 atomic_read(&clkdm->usecount) == 0)
87 		clkdm_sleep(clkdm);
88 	return 0;
89 }
90 
91 /*
92  * This sets pwrdm state (other than mpu & core. Currently only ON &
93  * RET are supported.
94  */
95 int omap_set_pwrdm_state(struct powerdomain *pwrdm, u32 pwrst)
96 {
97 	u8 curr_pwrst, next_pwrst;
98 	int sleep_switch = -1, ret = 0, hwsup = 0;
99 
100 	if (!pwrdm || IS_ERR(pwrdm))
101 		return -EINVAL;
102 
103 	while (!(pwrdm->pwrsts & (1 << pwrst))) {
104 		if (pwrst == PWRDM_POWER_OFF)
105 			return ret;
106 		pwrst--;
107 	}
108 
109 	next_pwrst = pwrdm_read_next_pwrst(pwrdm);
110 	if (next_pwrst == pwrst)
111 		return ret;
112 
113 	curr_pwrst = pwrdm_read_pwrst(pwrdm);
114 	if (curr_pwrst < PWRDM_POWER_ON) {
115 		if ((curr_pwrst > pwrst) &&
116 			(pwrdm->flags & PWRDM_HAS_LOWPOWERSTATECHANGE)) {
117 			sleep_switch = LOWPOWERSTATE_SWITCH;
118 		} else {
119 			hwsup = clkdm_in_hwsup(pwrdm->pwrdm_clkdms[0]);
120 			clkdm_wakeup(pwrdm->pwrdm_clkdms[0]);
121 			sleep_switch = FORCEWAKEUP_SWITCH;
122 		}
123 	}
124 
125 	ret = pwrdm_set_next_pwrst(pwrdm, pwrst);
126 	if (ret)
127 		pr_err("%s: unable to set power state of powerdomain: %s\n",
128 		       __func__, pwrdm->name);
129 
130 	switch (sleep_switch) {
131 	case FORCEWAKEUP_SWITCH:
132 		if (hwsup)
133 			clkdm_allow_idle(pwrdm->pwrdm_clkdms[0]);
134 		else
135 			clkdm_sleep(pwrdm->pwrdm_clkdms[0]);
136 		break;
137 	case LOWPOWERSTATE_SWITCH:
138 		pwrdm_set_lowpwrstchange(pwrdm);
139 		pwrdm_wait_transition(pwrdm);
140 		pwrdm_state_switch(pwrdm);
141 		break;
142 	}
143 
144 	return ret;
145 }
146 
147 
148 
149 /*
150  * This API is to be called during init to set the various voltage
151  * domains to the voltage as per the opp table. Typically we boot up
152  * at the nominal voltage. So this function finds out the rate of
153  * the clock associated with the voltage domain, finds out the correct
154  * opp entry and sets the voltage domain to the voltage specified
155  * in the opp entry
156  */
157 static int __init omap2_set_init_voltage(char *vdd_name, char *clk_name,
158 					 const char *oh_name)
159 {
160 	struct voltagedomain *voltdm;
161 	struct clk *clk;
162 	struct opp *opp;
163 	unsigned long freq, bootup_volt;
164 	struct device *dev;
165 
166 	if (!vdd_name || !clk_name || !oh_name) {
167 		pr_err("%s: invalid parameters\n", __func__);
168 		goto exit;
169 	}
170 
171 	dev = omap_device_get_by_hwmod_name(oh_name);
172 	if (IS_ERR(dev)) {
173 		pr_err("%s: Unable to get dev pointer for hwmod %s\n",
174 			__func__, oh_name);
175 		goto exit;
176 	}
177 
178 	voltdm = voltdm_lookup(vdd_name);
179 	if (IS_ERR(voltdm)) {
180 		pr_err("%s: unable to get vdd pointer for vdd_%s\n",
181 			__func__, vdd_name);
182 		goto exit;
183 	}
184 
185 	clk =  clk_get(NULL, clk_name);
186 	if (IS_ERR(clk)) {
187 		pr_err("%s: unable to get clk %s\n", __func__, clk_name);
188 		goto exit;
189 	}
190 
191 	freq = clk->rate;
192 	clk_put(clk);
193 
194 	rcu_read_lock();
195 	opp = opp_find_freq_ceil(dev, &freq);
196 	if (IS_ERR(opp)) {
197 		rcu_read_unlock();
198 		pr_err("%s: unable to find boot up OPP for vdd_%s\n",
199 			__func__, vdd_name);
200 		goto exit;
201 	}
202 
203 	bootup_volt = opp_get_voltage(opp);
204 	rcu_read_unlock();
205 	if (!bootup_volt) {
206 		pr_err("%s: unable to find voltage corresponding "
207 			"to the bootup OPP for vdd_%s\n", __func__, vdd_name);
208 		goto exit;
209 	}
210 
211 	voltdm_scale(voltdm, bootup_volt);
212 	return 0;
213 
214 exit:
215 	pr_err("%s: unable to set vdd_%s\n", __func__, vdd_name);
216 	return -EINVAL;
217 }
218 
219 #ifdef CONFIG_SUSPEND
220 static int omap_pm_enter(suspend_state_t suspend_state)
221 {
222 	int ret = 0;
223 
224 	if (!omap_pm_suspend)
225 		return -ENOENT; /* XXX doublecheck */
226 
227 	switch (suspend_state) {
228 	case PM_SUSPEND_STANDBY:
229 	case PM_SUSPEND_MEM:
230 		ret = omap_pm_suspend();
231 		break;
232 	default:
233 		ret = -EINVAL;
234 	}
235 
236 	return ret;
237 }
238 
239 static int omap_pm_begin(suspend_state_t state)
240 {
241 	disable_hlt();
242 	if (cpu_is_omap34xx())
243 		omap_prcm_irq_prepare();
244 	return 0;
245 }
246 
247 static void omap_pm_end(void)
248 {
249 	enable_hlt();
250 	return;
251 }
252 
253 static void omap_pm_finish(void)
254 {
255 	if (cpu_is_omap34xx())
256 		omap_prcm_irq_complete();
257 }
258 
259 static const struct platform_suspend_ops omap_pm_ops = {
260 	.begin		= omap_pm_begin,
261 	.end		= omap_pm_end,
262 	.enter		= omap_pm_enter,
263 	.finish		= omap_pm_finish,
264 	.valid		= suspend_valid_only_mem,
265 };
266 
267 #endif /* CONFIG_SUSPEND */
268 
269 static void __init omap3_init_voltages(void)
270 {
271 	if (!cpu_is_omap34xx())
272 		return;
273 
274 	omap2_set_init_voltage("mpu_iva", "dpll1_ck", "mpu");
275 	omap2_set_init_voltage("core", "l3_ick", "l3_main");
276 }
277 
278 static void __init omap4_init_voltages(void)
279 {
280 	if (!cpu_is_omap44xx())
281 		return;
282 
283 	omap2_set_init_voltage("mpu", "dpll_mpu_ck", "mpu");
284 	omap2_set_init_voltage("core", "l3_div_ck", "l3_main_1");
285 	omap2_set_init_voltage("iva", "dpll_iva_m5x2_ck", "iva");
286 }
287 
288 static int __init omap2_common_pm_init(void)
289 {
290 	if (!of_have_populated_dt())
291 		omap2_init_processor_devices();
292 	omap_pm_if_init();
293 
294 	return 0;
295 }
296 postcore_initcall(omap2_common_pm_init);
297 
298 int __init omap2_common_pm_late_init(void)
299 {
300 	/*
301 	 * In the case of DT, the PMIC and SR initialization will be done using
302 	 * a completely different mechanism.
303 	 * Disable this part if a DT blob is available.
304 	 */
305 	if (of_have_populated_dt())
306 		return 0;
307 
308 	/* Init the voltage layer */
309 	omap_pmic_late_init();
310 	omap_voltage_late_init();
311 
312 	/* Initialize the voltages */
313 	omap3_init_voltages();
314 	omap4_init_voltages();
315 
316 	/* Smartreflex device init */
317 	omap_devinit_smartreflex();
318 
319 #ifdef CONFIG_SUSPEND
320 	suspend_set_ops(&omap_pm_ops);
321 #endif
322 
323 	return 0;
324 }
325