xref: /openbmc/linux/arch/arm/mach-omap2/pm.c (revision 05bcf503)
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 <plat/omap-pm.h>
24 #include <plat/omap_device.h>
25 #include "common.h"
26 
27 #include "prcm-common.h"
28 #include "voltage.h"
29 #include "powerdomain.h"
30 #include "clockdomain.h"
31 #include "pm.h"
32 #include "twl-common.h"
33 
34 static struct omap_device_pm_latency *pm_lats;
35 
36 /*
37  * omap_pm_suspend: points to a function that does the SoC-specific
38  * suspend work
39  */
40 int (*omap_pm_suspend)(void);
41 
42 static int __init _init_omap_device(char *name)
43 {
44 	struct omap_hwmod *oh;
45 	struct platform_device *pdev;
46 
47 	oh = omap_hwmod_lookup(name);
48 	if (WARN(!oh, "%s: could not find omap_hwmod for %s\n",
49 		 __func__, name))
50 		return -ENODEV;
51 
52 	pdev = omap_device_build(oh->name, 0, oh, NULL, 0, pm_lats, 0, false);
53 	if (WARN(IS_ERR(pdev), "%s: could not build omap_device for %s\n",
54 		 __func__, name))
55 		return -ENODEV;
56 
57 	return 0;
58 }
59 
60 /*
61  * Build omap_devices for processors and bus.
62  */
63 static void __init omap2_init_processor_devices(void)
64 {
65 	_init_omap_device("mpu");
66 	if (omap3_has_iva())
67 		_init_omap_device("iva");
68 
69 	if (cpu_is_omap44xx()) {
70 		_init_omap_device("l3_main_1");
71 		_init_omap_device("dsp");
72 		_init_omap_device("iva");
73 	} else {
74 		_init_omap_device("l3_main");
75 	}
76 }
77 
78 /* Types of sleep_switch used in omap_set_pwrdm_state */
79 #define FORCEWAKEUP_SWITCH	0
80 #define LOWPOWERSTATE_SWITCH	1
81 
82 int __init omap_pm_clkdms_setup(struct clockdomain *clkdm, void *unused)
83 {
84 	if ((clkdm->flags & CLKDM_CAN_ENABLE_AUTO) &&
85 	    !(clkdm->flags & CLKDM_MISSING_IDLE_REPORTING))
86 		clkdm_allow_idle(clkdm);
87 	else if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP &&
88 		 atomic_read(&clkdm->usecount) == 0)
89 		clkdm_sleep(clkdm);
90 	return 0;
91 }
92 
93 /*
94  * This sets pwrdm state (other than mpu & core. Currently only ON &
95  * RET are supported.
96  */
97 int omap_set_pwrdm_state(struct powerdomain *pwrdm, u32 pwrst)
98 {
99 	u8 curr_pwrst, next_pwrst;
100 	int sleep_switch = -1, ret = 0, hwsup = 0;
101 
102 	if (!pwrdm || IS_ERR(pwrdm))
103 		return -EINVAL;
104 
105 	while (!(pwrdm->pwrsts & (1 << pwrst))) {
106 		if (pwrst == PWRDM_POWER_OFF)
107 			return ret;
108 		pwrst--;
109 	}
110 
111 	next_pwrst = pwrdm_read_next_pwrst(pwrdm);
112 	if (next_pwrst == pwrst)
113 		return ret;
114 
115 	curr_pwrst = pwrdm_read_pwrst(pwrdm);
116 	if (curr_pwrst < PWRDM_POWER_ON) {
117 		if ((curr_pwrst > pwrst) &&
118 			(pwrdm->flags & PWRDM_HAS_LOWPOWERSTATECHANGE)) {
119 			sleep_switch = LOWPOWERSTATE_SWITCH;
120 		} else {
121 			hwsup = clkdm_in_hwsup(pwrdm->pwrdm_clkdms[0]);
122 			clkdm_wakeup(pwrdm->pwrdm_clkdms[0]);
123 			sleep_switch = FORCEWAKEUP_SWITCH;
124 		}
125 	}
126 
127 	ret = pwrdm_set_next_pwrst(pwrdm, pwrst);
128 	if (ret)
129 		pr_err("%s: unable to set power state of powerdomain: %s\n",
130 		       __func__, pwrdm->name);
131 
132 	switch (sleep_switch) {
133 	case FORCEWAKEUP_SWITCH:
134 		if (hwsup)
135 			clkdm_allow_idle(pwrdm->pwrdm_clkdms[0]);
136 		else
137 			clkdm_sleep(pwrdm->pwrdm_clkdms[0]);
138 		break;
139 	case LOWPOWERSTATE_SWITCH:
140 		pwrdm_set_lowpwrstchange(pwrdm);
141 		pwrdm_wait_transition(pwrdm);
142 		pwrdm_state_switch(pwrdm);
143 		break;
144 	}
145 
146 	return ret;
147 }
148 
149 
150 
151 /*
152  * This API is to be called during init to set the various voltage
153  * domains to the voltage as per the opp table. Typically we boot up
154  * at the nominal voltage. So this function finds out the rate of
155  * the clock associated with the voltage domain, finds out the correct
156  * opp entry and sets the voltage domain to the voltage specified
157  * in the opp entry
158  */
159 static int __init omap2_set_init_voltage(char *vdd_name, char *clk_name,
160 					 const char *oh_name)
161 {
162 	struct voltagedomain *voltdm;
163 	struct clk *clk;
164 	struct opp *opp;
165 	unsigned long freq, bootup_volt;
166 	struct device *dev;
167 
168 	if (!vdd_name || !clk_name || !oh_name) {
169 		pr_err("%s: invalid parameters\n", __func__);
170 		goto exit;
171 	}
172 
173 	if (!strncmp(oh_name, "mpu", 3))
174 		/*
175 		 * All current OMAPs share voltage rail and clock
176 		 * source, so CPU0 is used to represent the MPU-SS.
177 		 */
178 		dev = get_cpu_device(0);
179 	else
180 		dev = omap_device_get_by_hwmod_name(oh_name);
181 
182 	if (IS_ERR(dev)) {
183 		pr_err("%s: Unable to get dev pointer for hwmod %s\n",
184 			__func__, oh_name);
185 		goto exit;
186 	}
187 
188 	voltdm = voltdm_lookup(vdd_name);
189 	if (!voltdm) {
190 		pr_err("%s: unable to get vdd pointer for vdd_%s\n",
191 			__func__, vdd_name);
192 		goto exit;
193 	}
194 
195 	clk =  clk_get(NULL, clk_name);
196 	if (IS_ERR(clk)) {
197 		pr_err("%s: unable to get clk %s\n", __func__, clk_name);
198 		goto exit;
199 	}
200 
201 	freq = clk_get_rate(clk);
202 	clk_put(clk);
203 
204 	rcu_read_lock();
205 	opp = opp_find_freq_ceil(dev, &freq);
206 	if (IS_ERR(opp)) {
207 		rcu_read_unlock();
208 		pr_err("%s: unable to find boot up OPP for vdd_%s\n",
209 			__func__, vdd_name);
210 		goto exit;
211 	}
212 
213 	bootup_volt = opp_get_voltage(opp);
214 	rcu_read_unlock();
215 	if (!bootup_volt) {
216 		pr_err("%s: unable to find voltage corresponding to the bootup OPP for vdd_%s\n",
217 		       __func__, vdd_name);
218 		goto exit;
219 	}
220 
221 	voltdm_scale(voltdm, bootup_volt);
222 	return 0;
223 
224 exit:
225 	pr_err("%s: unable to set vdd_%s\n", __func__, vdd_name);
226 	return -EINVAL;
227 }
228 
229 #ifdef CONFIG_SUSPEND
230 static int omap_pm_enter(suspend_state_t suspend_state)
231 {
232 	int ret = 0;
233 
234 	if (!omap_pm_suspend)
235 		return -ENOENT; /* XXX doublecheck */
236 
237 	switch (suspend_state) {
238 	case PM_SUSPEND_STANDBY:
239 	case PM_SUSPEND_MEM:
240 		ret = omap_pm_suspend();
241 		break;
242 	default:
243 		ret = -EINVAL;
244 	}
245 
246 	return ret;
247 }
248 
249 static int omap_pm_begin(suspend_state_t state)
250 {
251 	disable_hlt();
252 	if (cpu_is_omap34xx())
253 		omap_prcm_irq_prepare();
254 	return 0;
255 }
256 
257 static void omap_pm_end(void)
258 {
259 	enable_hlt();
260 	return;
261 }
262 
263 static void omap_pm_finish(void)
264 {
265 	if (cpu_is_omap34xx())
266 		omap_prcm_irq_complete();
267 }
268 
269 static const struct platform_suspend_ops omap_pm_ops = {
270 	.begin		= omap_pm_begin,
271 	.end		= omap_pm_end,
272 	.enter		= omap_pm_enter,
273 	.finish		= omap_pm_finish,
274 	.valid		= suspend_valid_only_mem,
275 };
276 
277 #endif /* CONFIG_SUSPEND */
278 
279 static void __init omap3_init_voltages(void)
280 {
281 	if (!cpu_is_omap34xx())
282 		return;
283 
284 	omap2_set_init_voltage("mpu_iva", "dpll1_ck", "mpu");
285 	omap2_set_init_voltage("core", "l3_ick", "l3_main");
286 }
287 
288 static void __init omap4_init_voltages(void)
289 {
290 	if (!cpu_is_omap44xx())
291 		return;
292 
293 	omap2_set_init_voltage("mpu", "dpll_mpu_ck", "mpu");
294 	omap2_set_init_voltage("core", "l3_div_ck", "l3_main_1");
295 	omap2_set_init_voltage("iva", "dpll_iva_m5x2_ck", "iva");
296 }
297 
298 static int __init omap2_common_pm_init(void)
299 {
300 	if (!of_have_populated_dt())
301 		omap2_init_processor_devices();
302 	omap_pm_if_init();
303 
304 	return 0;
305 }
306 postcore_initcall(omap2_common_pm_init);
307 
308 int __init omap2_common_pm_late_init(void)
309 {
310 	/*
311 	 * In the case of DT, the PMIC and SR initialization will be done using
312 	 * a completely different mechanism.
313 	 * Disable this part if a DT blob is available.
314 	 */
315 	if (of_have_populated_dt())
316 		return 0;
317 
318 	/* Init the voltage layer */
319 	omap_pmic_late_init();
320 	omap_voltage_late_init();
321 
322 	/* Initialize the voltages */
323 	omap3_init_voltages();
324 	omap4_init_voltages();
325 
326 	/* Smartreflex device init */
327 	omap_devinit_smartreflex();
328 
329 #ifdef CONFIG_SUSPEND
330 	suspend_set_ops(&omap_pm_ops);
331 #endif
332 
333 	return 0;
334 }
335