xref: /linux/arch/arm/mach-omap2/pm.c (revision 856e7c4b619af622d56b3b454f7bec32a170ac99)
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/clk.h>
20 #include <linux/cpu.h>
21 
22 #include <asm/system_misc.h>
23 
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 
34 #ifdef CONFIG_SUSPEND
35 /*
36  * omap_pm_suspend: points to a function that does the SoC-specific
37  * suspend work
38  */
39 static int (*omap_pm_suspend)(void);
40 #endif
41 
42 #ifdef CONFIG_PM
43 /**
44  * struct omap2_oscillator - Describe the board main oscillator latencies
45  * @startup_time: oscillator startup latency
46  * @shutdown_time: oscillator shutdown latency
47  */
48 struct omap2_oscillator {
49 	u32 startup_time;
50 	u32 shutdown_time;
51 };
52 
53 static struct omap2_oscillator oscillator = {
54 	.startup_time = ULONG_MAX,
55 	.shutdown_time = ULONG_MAX,
56 };
57 
58 void omap_pm_setup_oscillator(u32 tstart, u32 tshut)
59 {
60 	oscillator.startup_time = tstart;
61 	oscillator.shutdown_time = tshut;
62 }
63 
64 void omap_pm_get_oscillator(u32 *tstart, u32 *tshut)
65 {
66 	if (!tstart || !tshut)
67 		return;
68 
69 	*tstart = oscillator.startup_time;
70 	*tshut = oscillator.shutdown_time;
71 }
72 #endif
73 
74 int omap_pm_clkdms_setup(struct clockdomain *clkdm, void *unused)
75 {
76 	clkdm_allow_idle(clkdm);
77 	return 0;
78 }
79 
80 /*
81  * This API is to be called during init to set the various voltage
82  * domains to the voltage as per the opp table. Typically we boot up
83  * at the nominal voltage. So this function finds out the rate of
84  * the clock associated with the voltage domain, finds out the correct
85  * opp entry and sets the voltage domain to the voltage specified
86  * in the opp entry
87  */
88 static int __init omap2_set_init_voltage(char *vdd_name, char *clk_name,
89 					 const char *oh_name)
90 {
91 	struct voltagedomain *voltdm;
92 	struct clk *clk;
93 	struct dev_pm_opp *opp;
94 	unsigned long freq, bootup_volt;
95 	struct device *dev;
96 
97 	if (!vdd_name || !clk_name || !oh_name) {
98 		pr_err("%s: invalid parameters\n", __func__);
99 		goto exit;
100 	}
101 
102 	if (!strncmp(oh_name, "mpu", 3))
103 		/*
104 		 * All current OMAPs share voltage rail and clock
105 		 * source, so CPU0 is used to represent the MPU-SS.
106 		 */
107 		dev = get_cpu_device(0);
108 	else
109 		dev = omap_device_get_by_hwmod_name(oh_name);
110 
111 	if (IS_ERR(dev)) {
112 		pr_err("%s: Unable to get dev pointer for hwmod %s\n",
113 			__func__, oh_name);
114 		goto exit;
115 	}
116 
117 	voltdm = voltdm_lookup(vdd_name);
118 	if (!voltdm) {
119 		pr_err("%s: unable to get vdd pointer for vdd_%s\n",
120 			__func__, vdd_name);
121 		goto exit;
122 	}
123 
124 	clk =  clk_get(NULL, clk_name);
125 	if (IS_ERR(clk)) {
126 		pr_err("%s: unable to get clk %s\n", __func__, clk_name);
127 		goto exit;
128 	}
129 
130 	freq = clk_get_rate(clk);
131 	clk_put(clk);
132 
133 	opp = dev_pm_opp_find_freq_ceil(dev, &freq);
134 	if (IS_ERR(opp)) {
135 		pr_err("%s: unable to find boot up OPP for vdd_%s\n",
136 			__func__, vdd_name);
137 		goto exit;
138 	}
139 
140 	bootup_volt = dev_pm_opp_get_voltage(opp);
141 	dev_pm_opp_put(opp);
142 
143 	if (!bootup_volt) {
144 		pr_err("%s: unable to find voltage corresponding to the bootup OPP for vdd_%s\n",
145 		       __func__, vdd_name);
146 		goto exit;
147 	}
148 
149 	voltdm_scale(voltdm, bootup_volt);
150 	return 0;
151 
152 exit:
153 	pr_err("%s: unable to set vdd_%s\n", __func__, vdd_name);
154 	return -EINVAL;
155 }
156 
157 #ifdef CONFIG_SUSPEND
158 static int omap_pm_enter(suspend_state_t suspend_state)
159 {
160 	int ret = 0;
161 
162 	if (!omap_pm_suspend)
163 		return -ENOENT; /* XXX doublecheck */
164 
165 	switch (suspend_state) {
166 	case PM_SUSPEND_MEM:
167 		ret = omap_pm_suspend();
168 		break;
169 	default:
170 		ret = -EINVAL;
171 	}
172 
173 	return ret;
174 }
175 
176 static int omap_pm_begin(suspend_state_t state)
177 {
178 	cpu_idle_poll_ctrl(true);
179 	if (soc_is_omap34xx())
180 		omap_prcm_irq_prepare();
181 	return 0;
182 }
183 
184 static void omap_pm_end(void)
185 {
186 	cpu_idle_poll_ctrl(false);
187 }
188 
189 static void omap_pm_wake(void)
190 {
191 	if (soc_is_omap34xx())
192 		omap_prcm_irq_complete();
193 }
194 
195 static const struct platform_suspend_ops omap_pm_ops = {
196 	.begin		= omap_pm_begin,
197 	.end		= omap_pm_end,
198 	.enter		= omap_pm_enter,
199 	.wake		= omap_pm_wake,
200 	.valid		= suspend_valid_only_mem,
201 };
202 
203 /**
204  * omap_common_suspend_init - Set common suspend routines for OMAP SoCs
205  * @pm_suspend: function pointer to SoC specific suspend function
206  */
207 void omap_common_suspend_init(void *pm_suspend)
208 {
209 	omap_pm_suspend = pm_suspend;
210 	suspend_set_ops(&omap_pm_ops);
211 }
212 #endif /* CONFIG_SUSPEND */
213 
214 static void __init omap3_init_voltages(void)
215 {
216 	if (!soc_is_omap34xx())
217 		return;
218 
219 	omap2_set_init_voltage("mpu_iva", "dpll1_ck", "mpu");
220 	omap2_set_init_voltage("core", "l3_ick", "l3_main");
221 }
222 
223 static void __init omap4_init_voltages(void)
224 {
225 	if (!soc_is_omap44xx())
226 		return;
227 
228 	omap2_set_init_voltage("mpu", "dpll_mpu_ck", "mpu");
229 	omap2_set_init_voltage("core", "l3_div_ck", "l3_main_1");
230 	omap2_set_init_voltage("iva", "dpll_iva_m5x2_ck", "iva");
231 }
232 
233 int __maybe_unused omap_pm_nop_init(void)
234 {
235 	return 0;
236 }
237 
238 int (*omap_pm_soc_init)(void);
239 
240 int __init omap2_common_pm_late_init(void)
241 {
242 	int error;
243 
244 	if (!omap_pm_soc_init)
245 		return 0;
246 
247 	/* Init the voltage layer */
248 	omap3_twl_init();
249 	omap4_twl_init();
250 	omap_voltage_late_init();
251 
252 	/* Initialize the voltages */
253 	omap3_init_voltages();
254 	omap4_init_voltages();
255 
256 	/* Smartreflex device init */
257 	omap_devinit_smartreflex();
258 
259 	error = omap_pm_soc_init();
260 	if (error)
261 		pr_warn("%s: pm soc init failed: %i\n", __func__, error);
262 
263 	omap2_clk_enable_autoidle_all();
264 
265 	return 0;
266 }
267 omap_late_initcall(omap2_common_pm_late_init);
268