xref: /openbmc/linux/arch/arm/mach-omap2/pm.c (revision 9cdb81c7)
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 <plat/omap-pm.h>
21 #include <plat/omap_device.h>
22 #include "common.h"
23 
24 #include "prcm-common.h"
25 #include "voltage.h"
26 #include "powerdomain.h"
27 #include "clockdomain.h"
28 #include "pm.h"
29 #include "twl-common.h"
30 
31 static struct omap_device_pm_latency *pm_lats;
32 
33 /*
34  * omap_pm_suspend: points to a function that does the SoC-specific
35  * suspend work
36  */
37 int (*omap_pm_suspend)(void);
38 
39 static int __init _init_omap_device(char *name)
40 {
41 	struct omap_hwmod *oh;
42 	struct platform_device *pdev;
43 
44 	oh = omap_hwmod_lookup(name);
45 	if (WARN(!oh, "%s: could not find omap_hwmod for %s\n",
46 		 __func__, name))
47 		return -ENODEV;
48 
49 	pdev = omap_device_build(oh->name, 0, oh, NULL, 0, pm_lats, 0, false);
50 	if (WARN(IS_ERR(pdev), "%s: could not build omap_device for %s\n",
51 		 __func__, name))
52 		return -ENODEV;
53 
54 	return 0;
55 }
56 
57 /*
58  * Build omap_devices for processors and bus.
59  */
60 static void __init omap2_init_processor_devices(void)
61 {
62 	_init_omap_device("mpu");
63 	if (omap3_has_iva())
64 		_init_omap_device("iva");
65 
66 	if (cpu_is_omap44xx()) {
67 		_init_omap_device("l3_main_1");
68 		_init_omap_device("dsp");
69 		_init_omap_device("iva");
70 	} else {
71 		_init_omap_device("l3_main");
72 	}
73 }
74 
75 /* Types of sleep_switch used in omap_set_pwrdm_state */
76 #define FORCEWAKEUP_SWITCH	0
77 #define LOWPOWERSTATE_SWITCH	1
78 
79 int __init omap_pm_clkdms_setup(struct clockdomain *clkdm, void *unused)
80 {
81 	if (clkdm->flags & CLKDM_CAN_ENABLE_AUTO)
82 		clkdm_allow_idle(clkdm);
83 	else if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP &&
84 		 atomic_read(&clkdm->usecount) == 0)
85 		clkdm_sleep(clkdm);
86 	return 0;
87 }
88 
89 /*
90  * This sets pwrdm state (other than mpu & core. Currently only ON &
91  * RET are supported.
92  */
93 int omap_set_pwrdm_state(struct powerdomain *pwrdm, u32 pwrst)
94 {
95 	u8 curr_pwrst, next_pwrst;
96 	int sleep_switch = -1, ret = 0, hwsup = 0;
97 
98 	if (!pwrdm || IS_ERR(pwrdm))
99 		return -EINVAL;
100 
101 	while (!(pwrdm->pwrsts & (1 << pwrst))) {
102 		if (pwrst == PWRDM_POWER_OFF)
103 			return ret;
104 		pwrst--;
105 	}
106 
107 	next_pwrst = pwrdm_read_next_pwrst(pwrdm);
108 	if (next_pwrst == pwrst)
109 		return ret;
110 
111 	curr_pwrst = pwrdm_read_pwrst(pwrdm);
112 	if (curr_pwrst < PWRDM_POWER_ON) {
113 		if ((curr_pwrst > pwrst) &&
114 			(pwrdm->flags & PWRDM_HAS_LOWPOWERSTATECHANGE)) {
115 			sleep_switch = LOWPOWERSTATE_SWITCH;
116 		} else {
117 			hwsup = clkdm_in_hwsup(pwrdm->pwrdm_clkdms[0]);
118 			clkdm_wakeup(pwrdm->pwrdm_clkdms[0]);
119 			sleep_switch = FORCEWAKEUP_SWITCH;
120 		}
121 	}
122 
123 	ret = pwrdm_set_next_pwrst(pwrdm, pwrst);
124 	if (ret)
125 		pr_err("%s: unable to set power state of powerdomain: %s\n",
126 		       __func__, pwrdm->name);
127 
128 	switch (sleep_switch) {
129 	case FORCEWAKEUP_SWITCH:
130 		if (hwsup)
131 			clkdm_allow_idle(pwrdm->pwrdm_clkdms[0]);
132 		else
133 			clkdm_sleep(pwrdm->pwrdm_clkdms[0]);
134 		break;
135 	case LOWPOWERSTATE_SWITCH:
136 		pwrdm_set_lowpwrstchange(pwrdm);
137 		pwrdm_wait_transition(pwrdm);
138 		pwrdm_state_switch(pwrdm);
139 		break;
140 	}
141 
142 	return ret;
143 }
144 
145 
146 
147 /*
148  * This API is to be called during init to set the various voltage
149  * domains to the voltage as per the opp table. Typically we boot up
150  * at the nominal voltage. So this function finds out the rate of
151  * the clock associated with the voltage domain, finds out the correct
152  * opp entry and sets the voltage domain to the voltage specified
153  * in the opp entry
154  */
155 static int __init omap2_set_init_voltage(char *vdd_name, char *clk_name,
156 					 const char *oh_name)
157 {
158 	struct voltagedomain *voltdm;
159 	struct clk *clk;
160 	struct opp *opp;
161 	unsigned long freq, bootup_volt;
162 	struct device *dev;
163 
164 	if (!vdd_name || !clk_name || !oh_name) {
165 		pr_err("%s: invalid parameters\n", __func__);
166 		goto exit;
167 	}
168 
169 	dev = omap_device_get_by_hwmod_name(oh_name);
170 	if (IS_ERR(dev)) {
171 		pr_err("%s: Unable to get dev pointer for hwmod %s\n",
172 			__func__, oh_name);
173 		goto exit;
174 	}
175 
176 	voltdm = voltdm_lookup(vdd_name);
177 	if (IS_ERR(voltdm)) {
178 		pr_err("%s: unable to get vdd pointer for vdd_%s\n",
179 			__func__, vdd_name);
180 		goto exit;
181 	}
182 
183 	clk =  clk_get(NULL, clk_name);
184 	if (IS_ERR(clk)) {
185 		pr_err("%s: unable to get clk %s\n", __func__, clk_name);
186 		goto exit;
187 	}
188 
189 	freq = clk->rate;
190 	clk_put(clk);
191 
192 	rcu_read_lock();
193 	opp = opp_find_freq_ceil(dev, &freq);
194 	if (IS_ERR(opp)) {
195 		rcu_read_unlock();
196 		pr_err("%s: unable to find boot up OPP for vdd_%s\n",
197 			__func__, vdd_name);
198 		goto exit;
199 	}
200 
201 	bootup_volt = opp_get_voltage(opp);
202 	rcu_read_unlock();
203 	if (!bootup_volt) {
204 		pr_err("%s: unable to find voltage corresponding "
205 			"to the bootup OPP for vdd_%s\n", __func__, vdd_name);
206 		goto exit;
207 	}
208 
209 	voltdm_scale(voltdm, bootup_volt);
210 	return 0;
211 
212 exit:
213 	pr_err("%s: unable to set vdd_%s\n", __func__, vdd_name);
214 	return -EINVAL;
215 }
216 
217 #ifdef CONFIG_SUSPEND
218 static int omap_pm_enter(suspend_state_t suspend_state)
219 {
220 	int ret = 0;
221 
222 	if (!omap_pm_suspend)
223 		return -ENOENT; /* XXX doublecheck */
224 
225 	switch (suspend_state) {
226 	case PM_SUSPEND_STANDBY:
227 	case PM_SUSPEND_MEM:
228 		ret = omap_pm_suspend();
229 		break;
230 	default:
231 		ret = -EINVAL;
232 	}
233 
234 	return ret;
235 }
236 
237 static int omap_pm_begin(suspend_state_t state)
238 {
239 	disable_hlt();
240 	if (cpu_is_omap34xx())
241 		omap_prcm_irq_prepare();
242 	return 0;
243 }
244 
245 static void omap_pm_end(void)
246 {
247 	enable_hlt();
248 	return;
249 }
250 
251 static void omap_pm_finish(void)
252 {
253 	if (cpu_is_omap34xx())
254 		omap_prcm_irq_complete();
255 }
256 
257 static const struct platform_suspend_ops omap_pm_ops = {
258 	.begin		= omap_pm_begin,
259 	.end		= omap_pm_end,
260 	.enter		= omap_pm_enter,
261 	.finish		= omap_pm_finish,
262 	.valid		= suspend_valid_only_mem,
263 };
264 
265 #endif /* CONFIG_SUSPEND */
266 
267 static void __init omap3_init_voltages(void)
268 {
269 	if (!cpu_is_omap34xx())
270 		return;
271 
272 	omap2_set_init_voltage("mpu_iva", "dpll1_ck", "mpu");
273 	omap2_set_init_voltage("core", "l3_ick", "l3_main");
274 }
275 
276 static void __init omap4_init_voltages(void)
277 {
278 	if (!cpu_is_omap44xx())
279 		return;
280 
281 	omap2_set_init_voltage("mpu", "dpll_mpu_ck", "mpu");
282 	omap2_set_init_voltage("core", "l3_div_ck", "l3_main_1");
283 	omap2_set_init_voltage("iva", "dpll_iva_m5x2_ck", "iva");
284 }
285 
286 static int __init omap2_common_pm_init(void)
287 {
288 	if (!of_have_populated_dt())
289 		omap2_init_processor_devices();
290 	omap_pm_if_init();
291 
292 	return 0;
293 }
294 postcore_initcall(omap2_common_pm_init);
295 
296 static int __init omap2_common_pm_late_init(void)
297 {
298 	/*
299 	 * In the case of DT, the PMIC and SR initialization will be done using
300 	 * a completely different mechanism.
301 	 * Disable this part if a DT blob is available.
302 	 */
303 	if (of_have_populated_dt())
304 		return 0;
305 
306 	/* Init the voltage layer */
307 	omap_pmic_late_init();
308 	omap_voltage_late_init();
309 
310 	/* Initialize the voltages */
311 	omap3_init_voltages();
312 	omap4_init_voltages();
313 
314 	/* Smartreflex device init */
315 	omap_devinit_smartreflex();
316 
317 #ifdef CONFIG_SUSPEND
318 	suspend_set_ops(&omap_pm_ops);
319 #endif
320 
321 	return 0;
322 }
323 late_initcall(omap2_common_pm_late_init);
324