xref: /openbmc/linux/arch/arm/mach-omap2/pm.c (revision cbdf59ad)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * pm.c - Common OMAP2+ power management-related code
4  *
5  * Copyright (C) 2010 Texas Instruments, Inc.
6  * Copyright (C) 2010 Nokia Corporation
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <linux/io.h>
12 #include <linux/err.h>
13 #include <linux/pm_opp.h>
14 #include <linux/export.h>
15 #include <linux/suspend.h>
16 #include <linux/clk.h>
17 #include <linux/cpu.h>
18 
19 #include <asm/system_misc.h>
20 
21 #include "omap_device.h"
22 #include "common.h"
23 
24 #include "soc.h"
25 #include "prcm-common.h"
26 #include "voltage.h"
27 #include "powerdomain.h"
28 #include "clockdomain.h"
29 #include "pm.h"
30 
31 #ifdef CONFIG_SUSPEND
32 /*
33  * omap_pm_suspend: points to a function that does the SoC-specific
34  * suspend work
35  */
36 static int (*omap_pm_suspend)(void);
37 #endif
38 
39 #ifdef CONFIG_PM
40 /**
41  * struct omap2_oscillator - Describe the board main oscillator latencies
42  * @startup_time: oscillator startup latency
43  * @shutdown_time: oscillator shutdown latency
44  */
45 struct omap2_oscillator {
46 	u32 startup_time;
47 	u32 shutdown_time;
48 };
49 
50 static struct omap2_oscillator oscillator = {
51 	.startup_time = ULONG_MAX,
52 	.shutdown_time = ULONG_MAX,
53 };
54 
55 void omap_pm_setup_oscillator(u32 tstart, u32 tshut)
56 {
57 	oscillator.startup_time = tstart;
58 	oscillator.shutdown_time = tshut;
59 }
60 
61 void omap_pm_get_oscillator(u32 *tstart, u32 *tshut)
62 {
63 	if (!tstart || !tshut)
64 		return;
65 
66 	*tstart = oscillator.startup_time;
67 	*tshut = oscillator.shutdown_time;
68 }
69 #endif
70 
71 int omap_pm_clkdms_setup(struct clockdomain *clkdm, void *unused)
72 {
73 	clkdm_allow_idle(clkdm);
74 	return 0;
75 }
76 
77 /*
78  * This API is to be called during init to set the various voltage
79  * domains to the voltage as per the opp table. Typically we boot up
80  * at the nominal voltage. So this function finds out the rate of
81  * the clock associated with the voltage domain, finds out the correct
82  * opp entry and sets the voltage domain to the voltage specified
83  * in the opp entry
84  */
85 static int __init omap2_set_init_voltage(char *vdd_name, char *clk_name,
86 					 const char *oh_name)
87 {
88 	struct voltagedomain *voltdm;
89 	struct clk *clk;
90 	struct dev_pm_opp *opp;
91 	unsigned long freq, bootup_volt;
92 	struct device *dev;
93 
94 	if (!vdd_name || !clk_name || !oh_name) {
95 		pr_err("%s: invalid parameters\n", __func__);
96 		goto exit;
97 	}
98 
99 	if (!strncmp(oh_name, "mpu", 3))
100 		/*
101 		 * All current OMAPs share voltage rail and clock
102 		 * source, so CPU0 is used to represent the MPU-SS.
103 		 */
104 		dev = get_cpu_device(0);
105 	else
106 		dev = omap_device_get_by_hwmod_name(oh_name);
107 
108 	if (IS_ERR(dev)) {
109 		pr_err("%s: Unable to get dev pointer for hwmod %s\n",
110 			__func__, oh_name);
111 		goto exit;
112 	}
113 
114 	voltdm = voltdm_lookup(vdd_name);
115 	if (!voltdm) {
116 		pr_err("%s: unable to get vdd pointer for vdd_%s\n",
117 			__func__, vdd_name);
118 		goto exit;
119 	}
120 
121 	clk =  clk_get(NULL, clk_name);
122 	if (IS_ERR(clk)) {
123 		pr_err("%s: unable to get clk %s\n", __func__, clk_name);
124 		goto exit;
125 	}
126 
127 	freq = clk_get_rate(clk);
128 	clk_put(clk);
129 
130 	opp = dev_pm_opp_find_freq_ceil(dev, &freq);
131 	if (IS_ERR(opp)) {
132 		pr_err("%s: unable to find boot up OPP for vdd_%s\n",
133 			__func__, vdd_name);
134 		goto exit;
135 	}
136 
137 	bootup_volt = dev_pm_opp_get_voltage(opp);
138 	dev_pm_opp_put(opp);
139 
140 	if (!bootup_volt) {
141 		pr_err("%s: unable to find voltage corresponding to the bootup OPP for vdd_%s\n",
142 		       __func__, vdd_name);
143 		goto exit;
144 	}
145 
146 	voltdm_scale(voltdm, bootup_volt);
147 	return 0;
148 
149 exit:
150 	pr_err("%s: unable to set vdd_%s\n", __func__, vdd_name);
151 	return -EINVAL;
152 }
153 
154 #ifdef CONFIG_SUSPEND
155 static int omap_pm_enter(suspend_state_t suspend_state)
156 {
157 	int ret = 0;
158 
159 	if (!omap_pm_suspend)
160 		return -ENOENT; /* XXX doublecheck */
161 
162 	switch (suspend_state) {
163 	case PM_SUSPEND_MEM:
164 		ret = omap_pm_suspend();
165 		break;
166 	default:
167 		ret = -EINVAL;
168 	}
169 
170 	return ret;
171 }
172 
173 static int omap_pm_begin(suspend_state_t state)
174 {
175 	cpu_idle_poll_ctrl(true);
176 	if (soc_is_omap34xx())
177 		omap_prcm_irq_prepare();
178 	return 0;
179 }
180 
181 static void omap_pm_end(void)
182 {
183 	cpu_idle_poll_ctrl(false);
184 }
185 
186 static void omap_pm_wake(void)
187 {
188 	if (soc_is_omap34xx())
189 		omap_prcm_irq_complete();
190 }
191 
192 static const struct platform_suspend_ops omap_pm_ops = {
193 	.begin		= omap_pm_begin,
194 	.end		= omap_pm_end,
195 	.enter		= omap_pm_enter,
196 	.wake		= omap_pm_wake,
197 	.valid		= suspend_valid_only_mem,
198 };
199 
200 /**
201  * omap_common_suspend_init - Set common suspend routines for OMAP SoCs
202  * @pm_suspend: function pointer to SoC specific suspend function
203  */
204 void omap_common_suspend_init(void *pm_suspend)
205 {
206 	omap_pm_suspend = pm_suspend;
207 	suspend_set_ops(&omap_pm_ops);
208 }
209 #endif /* CONFIG_SUSPEND */
210 
211 static void __init omap3_init_voltages(void)
212 {
213 	if (!soc_is_omap34xx())
214 		return;
215 
216 	omap2_set_init_voltage("mpu_iva", "dpll1_ck", "mpu");
217 	omap2_set_init_voltage("core", "l3_ick", "l3_main");
218 }
219 
220 static void __init omap4_init_voltages(void)
221 {
222 	if (!soc_is_omap44xx())
223 		return;
224 
225 	omap2_set_init_voltage("mpu", "dpll_mpu_ck", "mpu");
226 	omap2_set_init_voltage("core", "l3_div_ck", "l3_main_1");
227 	omap2_set_init_voltage("iva", "dpll_iva_m5x2_ck", "iva");
228 }
229 
230 int __maybe_unused omap_pm_nop_init(void)
231 {
232 	return 0;
233 }
234 
235 int (*omap_pm_soc_init)(void);
236 
237 int __init omap2_common_pm_late_init(void)
238 {
239 	int error;
240 
241 	if (!omap_pm_soc_init)
242 		return 0;
243 
244 	/* Init the voltage layer */
245 	omap3_twl_init();
246 	omap4_twl_init();
247 	omap_voltage_late_init();
248 
249 	/* Initialize the voltages */
250 	omap3_init_voltages();
251 	omap4_init_voltages();
252 
253 	/* Smartreflex device init */
254 	omap_devinit_smartreflex();
255 
256 	error = omap_pm_soc_init();
257 	if (error)
258 		pr_warn("%s: pm soc init failed: %i\n", __func__, error);
259 
260 	omap2_clk_enable_autoidle_all();
261 
262 	return 0;
263 }
264 omap_late_initcall(omap2_common_pm_late_init);
265