xref: /openbmc/linux/arch/arm/mach-omap2/pm.c (revision 7587eb18)
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/pm_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 #ifdef CONFIG_SUSPEND
36 /*
37  * omap_pm_suspend: points to a function that does the SoC-specific
38  * suspend work
39  */
40 static int (*omap_pm_suspend)(void);
41 #endif
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);
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 int __init omap_pm_clkdms_setup(struct clockdomain *clkdm, void *unused)
112 {
113 	/* XXX The usecount test is racy */
114 	if ((clkdm->flags & CLKDM_CAN_ENABLE_AUTO) &&
115 	    !(clkdm->flags & CLKDM_MISSING_IDLE_REPORTING))
116 		clkdm_allow_idle(clkdm);
117 	else if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP &&
118 		 clkdm->usecount == 0)
119 		clkdm_sleep(clkdm);
120 	return 0;
121 }
122 
123 /*
124  * This API is to be called during init to set the various voltage
125  * domains to the voltage as per the opp table. Typically we boot up
126  * at the nominal voltage. So this function finds out the rate of
127  * the clock associated with the voltage domain, finds out the correct
128  * opp entry and sets the voltage domain to the voltage specified
129  * in the opp entry
130  */
131 static int __init omap2_set_init_voltage(char *vdd_name, char *clk_name,
132 					 const char *oh_name)
133 {
134 	struct voltagedomain *voltdm;
135 	struct clk *clk;
136 	struct dev_pm_opp *opp;
137 	unsigned long freq, bootup_volt;
138 	struct device *dev;
139 
140 	if (!vdd_name || !clk_name || !oh_name) {
141 		pr_err("%s: invalid parameters\n", __func__);
142 		goto exit;
143 	}
144 
145 	if (!strncmp(oh_name, "mpu", 3))
146 		/*
147 		 * All current OMAPs share voltage rail and clock
148 		 * source, so CPU0 is used to represent the MPU-SS.
149 		 */
150 		dev = get_cpu_device(0);
151 	else
152 		dev = omap_device_get_by_hwmod_name(oh_name);
153 
154 	if (IS_ERR(dev)) {
155 		pr_err("%s: Unable to get dev pointer for hwmod %s\n",
156 			__func__, oh_name);
157 		goto exit;
158 	}
159 
160 	voltdm = voltdm_lookup(vdd_name);
161 	if (!voltdm) {
162 		pr_err("%s: unable to get vdd pointer for vdd_%s\n",
163 			__func__, vdd_name);
164 		goto exit;
165 	}
166 
167 	clk =  clk_get(NULL, clk_name);
168 	if (IS_ERR(clk)) {
169 		pr_err("%s: unable to get clk %s\n", __func__, clk_name);
170 		goto exit;
171 	}
172 
173 	freq = clk_get_rate(clk);
174 	clk_put(clk);
175 
176 	rcu_read_lock();
177 	opp = dev_pm_opp_find_freq_ceil(dev, &freq);
178 	if (IS_ERR(opp)) {
179 		rcu_read_unlock();
180 		pr_err("%s: unable to find boot up OPP for vdd_%s\n",
181 			__func__, vdd_name);
182 		goto exit;
183 	}
184 
185 	bootup_volt = dev_pm_opp_get_voltage(opp);
186 	rcu_read_unlock();
187 	if (!bootup_volt) {
188 		pr_err("%s: unable to find voltage corresponding to the bootup OPP for vdd_%s\n",
189 		       __func__, vdd_name);
190 		goto exit;
191 	}
192 
193 	voltdm_scale(voltdm, bootup_volt);
194 	return 0;
195 
196 exit:
197 	pr_err("%s: unable to set vdd_%s\n", __func__, vdd_name);
198 	return -EINVAL;
199 }
200 
201 #ifdef CONFIG_SUSPEND
202 static int omap_pm_enter(suspend_state_t suspend_state)
203 {
204 	int ret = 0;
205 
206 	if (!omap_pm_suspend)
207 		return -ENOENT; /* XXX doublecheck */
208 
209 	switch (suspend_state) {
210 	case PM_SUSPEND_STANDBY:
211 	case PM_SUSPEND_MEM:
212 		ret = omap_pm_suspend();
213 		break;
214 	default:
215 		ret = -EINVAL;
216 	}
217 
218 	return ret;
219 }
220 
221 static int omap_pm_begin(suspend_state_t state)
222 {
223 	cpu_idle_poll_ctrl(true);
224 	if (cpu_is_omap34xx())
225 		omap_prcm_irq_prepare();
226 	return 0;
227 }
228 
229 static void omap_pm_end(void)
230 {
231 	cpu_idle_poll_ctrl(false);
232 }
233 
234 static void omap_pm_finish(void)
235 {
236 	if (cpu_is_omap34xx())
237 		omap_prcm_irq_complete();
238 }
239 
240 static const struct platform_suspend_ops omap_pm_ops = {
241 	.begin		= omap_pm_begin,
242 	.end		= omap_pm_end,
243 	.enter		= omap_pm_enter,
244 	.finish		= omap_pm_finish,
245 	.valid		= suspend_valid_only_mem,
246 };
247 
248 /**
249  * omap_common_suspend_init - Set common suspend routines for OMAP SoCs
250  * @pm_suspend: function pointer to SoC specific suspend function
251  */
252 void omap_common_suspend_init(void *pm_suspend)
253 {
254 	omap_pm_suspend = pm_suspend;
255 	suspend_set_ops(&omap_pm_ops);
256 }
257 #endif /* CONFIG_SUSPEND */
258 
259 static void __init omap3_init_voltages(void)
260 {
261 	if (!cpu_is_omap34xx())
262 		return;
263 
264 	omap2_set_init_voltage("mpu_iva", "dpll1_ck", "mpu");
265 	omap2_set_init_voltage("core", "l3_ick", "l3_main");
266 }
267 
268 static void __init omap4_init_voltages(void)
269 {
270 	if (!cpu_is_omap44xx())
271 		return;
272 
273 	omap2_set_init_voltage("mpu", "dpll_mpu_ck", "mpu");
274 	omap2_set_init_voltage("core", "l3_div_ck", "l3_main_1");
275 	omap2_set_init_voltage("iva", "dpll_iva_m5x2_ck", "iva");
276 }
277 
278 static inline void omap_init_cpufreq(void)
279 {
280 	struct platform_device_info devinfo = { .name = "omap-cpufreq" };
281 
282 	if (!of_have_populated_dt())
283 		platform_device_register_full(&devinfo);
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 omap_postcore_initcall(omap2_common_pm_init);
295 
296 int __init omap2_common_pm_late_init(void)
297 {
298 	if (of_have_populated_dt()) {
299 		omap3_twl_init();
300 		omap4_twl_init();
301 	}
302 
303 	/* Init the voltage layer */
304 	omap_pmic_late_init();
305 	omap_voltage_late_init();
306 
307 	/* Initialize the voltages */
308 	omap3_init_voltages();
309 	omap4_init_voltages();
310 
311 	/* Smartreflex device init */
312 	omap_devinit_smartreflex();
313 
314 	/* cpufreq dummy device instantiation */
315 	omap_init_cpufreq();
316 
317 	return 0;
318 }
319