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v3.15
  1/*
  2 * OMAP2 Power Management Routines
  3 *
  4 * Copyright (C) 2005 Texas Instruments, Inc.
  5 * Copyright (C) 2006-2008 Nokia Corporation
  6 *
  7 * Written by:
  8 * Richard Woodruff <r-woodruff2@ti.com>
  9 * Tony Lindgren
 10 * Juha Yrjola
 11 * Amit Kucheria <amit.kucheria@nokia.com>
 12 * Igor Stoppa <igor.stoppa@nokia.com>
 13 *
 14 * Based on pm.c for omap1
 15 *
 16 * This program is free software; you can redistribute it and/or modify
 17 * it under the terms of the GNU General Public License version 2 as
 18 * published by the Free Software Foundation.
 19 */
 20
 21#include <linux/suspend.h>
 22#include <linux/sched.h>
 23#include <linux/proc_fs.h>
 24#include <linux/interrupt.h>
 25#include <linux/sysfs.h>
 26#include <linux/module.h>
 27#include <linux/delay.h>
 
 28#include <linux/clk-provider.h>
 29#include <linux/irq.h>
 30#include <linux/time.h>
 31#include <linux/gpio.h>
 32#include <linux/platform_data/gpio-omap.h>
 33
 34#include <asm/fncpy.h>
 35
 36#include <asm/mach/time.h>
 37#include <asm/mach/irq.h>
 38#include <asm/mach-types.h>
 39#include <asm/system_misc.h>
 40
 41#include <linux/omap-dma.h>
 42
 43#include "soc.h"
 44#include "common.h"
 45#include "clock.h"
 46#include "prm2xxx.h"
 47#include "prm-regbits-24xx.h"
 48#include "cm2xxx.h"
 49#include "cm-regbits-24xx.h"
 50#include "sdrc.h"
 51#include "sram.h"
 52#include "pm.h"
 53#include "control.h"
 54#include "powerdomain.h"
 55#include "clockdomain.h"
 56
 57static void (*omap2_sram_suspend)(u32 dllctrl, void __iomem *sdrc_dlla_ctrl,
 58				  void __iomem *sdrc_power);
 59
 60static struct powerdomain *mpu_pwrdm, *core_pwrdm;
 61static struct clockdomain *dsp_clkdm, *mpu_clkdm, *wkup_clkdm, *gfx_clkdm;
 62
 63static struct clk *osc_ck, *emul_ck;
 64
 65static int omap2_enter_full_retention(void)
 66{
 67	u32 l;
 68
 69	/* There is 1 reference hold for all children of the oscillator
 70	 * clock, the following will remove it. If no one else uses the
 71	 * oscillator itself it will be disabled if/when we enter retention
 72	 * mode.
 73	 */
 74	clk_disable(osc_ck);
 75
 76	/* Clear old wake-up events */
 77	/* REVISIT: These write to reserved bits? */
 78	omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
 79	omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
 80	omap2_prm_write_mod_reg(0xffffffff, WKUP_MOD, PM_WKST);
 81
 82	pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_RET);
 83	pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
 84
 85	/* Workaround to kill USB */
 86	l = omap_ctrl_readl(OMAP2_CONTROL_DEVCONF0) | OMAP24XX_USBSTANDBYCTRL;
 87	omap_ctrl_writel(l, OMAP2_CONTROL_DEVCONF0);
 88
 89	omap2_gpio_prepare_for_idle(0);
 90
 91	/* One last check for pending IRQs to avoid extra latency due
 92	 * to sleeping unnecessarily. */
 93	if (omap_irq_pending())
 94		goto no_sleep;
 95
 96	/* Jump to SRAM suspend code */
 97	omap2_sram_suspend(sdrc_read_reg(SDRC_DLLA_CTRL),
 98			   OMAP_SDRC_REGADDR(SDRC_DLLA_CTRL),
 99			   OMAP_SDRC_REGADDR(SDRC_POWER));
100
101no_sleep:
102	omap2_gpio_resume_after_idle();
103
104	clk_enable(osc_ck);
105
106	/* clear CORE wake-up events */
107	omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
108	omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
109
110	/* wakeup domain events - bit 1: GPT1, bit5 GPIO */
111	omap2_prm_clear_mod_reg_bits(0x4 | 0x1, WKUP_MOD, PM_WKST);
112
113	/* MPU domain wake events */
114	l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
115	if (l & 0x01)
116		omap2_prm_write_mod_reg(0x01, OCP_MOD,
117				  OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
118	if (l & 0x20)
119		omap2_prm_write_mod_reg(0x20, OCP_MOD,
120				  OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
121
122	/* Mask future PRCM-to-MPU interrupts */
123	omap2_prm_write_mod_reg(0x0, OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
124
125	pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
126	pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_ON);
127
128	return 0;
129}
130
131static int sti_console_enabled;
132
133static int omap2_allow_mpu_retention(void)
134{
135	if (!omap2xxx_cm_mpu_retention_allowed())
136		return 0;
137	if (sti_console_enabled)
138		return 0;
139
140	return 1;
141}
142
143static void omap2_enter_mpu_retention(void)
144{
145	const int zero = 0;
146
147	/* The peripherals seem not to be able to wake up the MPU when
148	 * it is in retention mode. */
149	if (omap2_allow_mpu_retention()) {
150		/* REVISIT: These write to reserved bits? */
151		omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
152		omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
153		omap2_prm_write_mod_reg(0xffffffff, WKUP_MOD, PM_WKST);
154
155		/* Try to enter MPU retention */
156		pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
157
158	} else {
159		/* Block MPU retention */
160		pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
161	}
162
163	/* WFI */
164	asm("mcr p15, 0, %0, c7, c0, 4" : : "r" (zero) : "memory", "cc");
165
166	pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
167}
168
169static int omap2_can_sleep(void)
170{
171	if (omap2xxx_cm_fclks_active())
172		return 0;
173	if (__clk_is_enabled(osc_ck))
174		return 0;
175	if (omap_dma_running())
176		return 0;
177
178	return 1;
179}
180
181static void omap2_pm_idle(void)
182{
183	if (!omap2_can_sleep()) {
184		if (omap_irq_pending())
185			return;
186		omap2_enter_mpu_retention();
187		return;
188	}
189
190	if (omap_irq_pending())
191		return;
192
193	omap2_enter_full_retention();
194}
195
196static void __init prcm_setup_regs(void)
197{
198	int i, num_mem_banks;
199	struct powerdomain *pwrdm;
200
201	/*
202	 * Enable autoidle
203	 * XXX This should be handled by hwmod code or PRCM init code
204	 */
205	omap2_prm_write_mod_reg(OMAP24XX_AUTOIDLE_MASK, OCP_MOD,
206			  OMAP2_PRCM_SYSCONFIG_OFFSET);
207
208	/*
209	 * Set CORE powerdomain memory banks to retain their contents
210	 * during RETENTION
211	 */
212	num_mem_banks = pwrdm_get_mem_bank_count(core_pwrdm);
213	for (i = 0; i < num_mem_banks; i++)
214		pwrdm_set_mem_retst(core_pwrdm, i, PWRDM_POWER_RET);
215
216	pwrdm_set_logic_retst(core_pwrdm, PWRDM_POWER_RET);
217
218	pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
219
220	/* Force-power down DSP, GFX powerdomains */
221
222	pwrdm = clkdm_get_pwrdm(dsp_clkdm);
223	pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
224
225	pwrdm = clkdm_get_pwrdm(gfx_clkdm);
226	pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
227
228	/* Enable hardware-supervised idle for all clkdms */
229	clkdm_for_each(omap_pm_clkdms_setup, NULL);
230	clkdm_add_wkdep(mpu_clkdm, wkup_clkdm);
231
232#ifdef CONFIG_SUSPEND
233	omap_pm_suspend = omap2_enter_full_retention;
234#endif
235
236	/* REVISIT: Configure number of 32 kHz clock cycles for sys_clk
237	 * stabilisation */
238	omap2_prm_write_mod_reg(15 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
239				OMAP2_PRCM_CLKSSETUP_OFFSET);
240
241	/* Configure automatic voltage transition */
242	omap2_prm_write_mod_reg(2 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
243				OMAP2_PRCM_VOLTSETUP_OFFSET);
244	omap2_prm_write_mod_reg(OMAP24XX_AUTO_EXTVOLT_MASK |
245				(0x1 << OMAP24XX_SETOFF_LEVEL_SHIFT) |
246				OMAP24XX_MEMRETCTRL_MASK |
247				(0x1 << OMAP24XX_SETRET_LEVEL_SHIFT) |
248				(0x0 << OMAP24XX_VOLT_LEVEL_SHIFT),
249				OMAP24XX_GR_MOD, OMAP2_PRCM_VOLTCTRL_OFFSET);
250
251	/* Enable wake-up events */
252	omap2_prm_write_mod_reg(OMAP24XX_EN_GPIOS_MASK | OMAP24XX_EN_GPT1_MASK,
253				WKUP_MOD, PM_WKEN);
 
 
 
 
254}
255
256int __init omap2_pm_init(void)
257{
258	u32 l;
259
260	printk(KERN_INFO "Power Management for OMAP2 initializing\n");
261	l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_REVISION_OFFSET);
262	printk(KERN_INFO "PRCM revision %d.%d\n", (l >> 4) & 0x0f, l & 0x0f);
263
264	/* Look up important powerdomains */
265
266	mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
267	if (!mpu_pwrdm)
268		pr_err("PM: mpu_pwrdm not found\n");
269
270	core_pwrdm = pwrdm_lookup("core_pwrdm");
271	if (!core_pwrdm)
272		pr_err("PM: core_pwrdm not found\n");
273
274	/* Look up important clockdomains */
275
276	mpu_clkdm = clkdm_lookup("mpu_clkdm");
277	if (!mpu_clkdm)
278		pr_err("PM: mpu_clkdm not found\n");
279
280	wkup_clkdm = clkdm_lookup("wkup_clkdm");
281	if (!wkup_clkdm)
282		pr_err("PM: wkup_clkdm not found\n");
283
284	dsp_clkdm = clkdm_lookup("dsp_clkdm");
285	if (!dsp_clkdm)
286		pr_err("PM: dsp_clkdm not found\n");
287
288	gfx_clkdm = clkdm_lookup("gfx_clkdm");
289	if (!gfx_clkdm)
290		pr_err("PM: gfx_clkdm not found\n");
291
292
293	osc_ck = clk_get(NULL, "osc_ck");
294	if (IS_ERR(osc_ck)) {
295		printk(KERN_ERR "could not get osc_ck\n");
296		return -ENODEV;
297	}
298
299	if (cpu_is_omap242x()) {
300		emul_ck = clk_get(NULL, "emul_ck");
301		if (IS_ERR(emul_ck)) {
302			printk(KERN_ERR "could not get emul_ck\n");
303			clk_put(osc_ck);
304			return -ENODEV;
305		}
306	}
307
308	prcm_setup_regs();
309
310	/*
311	 * We copy the assembler sleep/wakeup routines to SRAM.
312	 * These routines need to be in SRAM as that's the only
313	 * memory the MPU can see when it wakes up after the entire
314	 * chip enters idle.
315	 */
316	omap2_sram_suspend = omap_sram_push(omap24xx_cpu_suspend,
317					    omap24xx_cpu_suspend_sz);
318
319	arm_pm_idle = omap2_pm_idle;
320
321	return 0;
322}
v4.17
  1/*
  2 * OMAP2 Power Management Routines
  3 *
  4 * Copyright (C) 2005 Texas Instruments, Inc.
  5 * Copyright (C) 2006-2008 Nokia Corporation
  6 *
  7 * Written by:
  8 * Richard Woodruff <r-woodruff2@ti.com>
  9 * Tony Lindgren
 10 * Juha Yrjola
 11 * Amit Kucheria <amit.kucheria@nokia.com>
 12 * Igor Stoppa <igor.stoppa@nokia.com>
 13 *
 14 * Based on pm.c for omap1
 15 *
 16 * This program is free software; you can redistribute it and/or modify
 17 * it under the terms of the GNU General Public License version 2 as
 18 * published by the Free Software Foundation.
 19 */
 20
 21#include <linux/suspend.h>
 22#include <linux/sched.h>
 23#include <linux/proc_fs.h>
 24#include <linux/interrupt.h>
 25#include <linux/sysfs.h>
 26#include <linux/module.h>
 27#include <linux/delay.h>
 28#include <linux/clk.h>
 29#include <linux/clk-provider.h>
 30#include <linux/irq.h>
 31#include <linux/time.h>
 32#include <linux/gpio.h>
 33#include <linux/platform_data/gpio-omap.h>
 34
 35#include <asm/fncpy.h>
 36
 37#include <asm/mach/time.h>
 38#include <asm/mach/irq.h>
 39#include <asm/mach-types.h>
 40#include <asm/system_misc.h>
 41
 42#include <linux/omap-dma.h>
 43
 44#include "soc.h"
 45#include "common.h"
 46#include "clock.h"
 47#include "prm2xxx.h"
 48#include "prm-regbits-24xx.h"
 49#include "cm2xxx.h"
 50#include "cm-regbits-24xx.h"
 51#include "sdrc.h"
 52#include "sram.h"
 53#include "pm.h"
 54#include "control.h"
 55#include "powerdomain.h"
 56#include "clockdomain.h"
 57
 58static void (*omap2_sram_suspend)(u32 dllctrl, void __iomem *sdrc_dlla_ctrl,
 59				  void __iomem *sdrc_power);
 60
 61static struct powerdomain *mpu_pwrdm, *core_pwrdm;
 62static struct clockdomain *dsp_clkdm, *mpu_clkdm, *wkup_clkdm, *gfx_clkdm;
 63
 64static struct clk *osc_ck, *emul_ck;
 65
 66static int omap2_enter_full_retention(void)
 67{
 68	u32 l;
 69
 70	/* There is 1 reference hold for all children of the oscillator
 71	 * clock, the following will remove it. If no one else uses the
 72	 * oscillator itself it will be disabled if/when we enter retention
 73	 * mode.
 74	 */
 75	clk_disable(osc_ck);
 76
 77	/* Clear old wake-up events */
 78	/* REVISIT: These write to reserved bits? */
 79	omap_prm_clear_mod_irqs(CORE_MOD, PM_WKST1, ~0);
 80	omap_prm_clear_mod_irqs(CORE_MOD, OMAP24XX_PM_WKST2, ~0);
 81	omap_prm_clear_mod_irqs(WKUP_MOD, PM_WKST, ~0);
 82
 83	pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_RET);
 84	pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
 85
 86	/* Workaround to kill USB */
 87	l = omap_ctrl_readl(OMAP2_CONTROL_DEVCONF0) | OMAP24XX_USBSTANDBYCTRL;
 88	omap_ctrl_writel(l, OMAP2_CONTROL_DEVCONF0);
 89
 90	omap2_gpio_prepare_for_idle(0);
 91
 92	/* One last check for pending IRQs to avoid extra latency due
 93	 * to sleeping unnecessarily. */
 94	if (omap_irq_pending())
 95		goto no_sleep;
 96
 97	/* Jump to SRAM suspend code */
 98	omap2_sram_suspend(sdrc_read_reg(SDRC_DLLA_CTRL),
 99			   OMAP_SDRC_REGADDR(SDRC_DLLA_CTRL),
100			   OMAP_SDRC_REGADDR(SDRC_POWER));
101
102no_sleep:
103	omap2_gpio_resume_after_idle();
104
105	clk_enable(osc_ck);
106
107	/* clear CORE wake-up events */
108	omap_prm_clear_mod_irqs(CORE_MOD, PM_WKST1, ~0);
109	omap_prm_clear_mod_irqs(CORE_MOD, OMAP24XX_PM_WKST2, ~0);
110
111	/* wakeup domain events - bit 1: GPT1, bit5 GPIO */
112	omap_prm_clear_mod_irqs(WKUP_MOD, PM_WKST, 0x4 | 0x1);
113
114	/* MPU domain wake events */
115	omap_prm_clear_mod_irqs(OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET, 0x1);
 
 
 
 
 
 
116
117	omap_prm_clear_mod_irqs(OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET, 0x20);
 
118
119	pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
120	pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_ON);
121
122	return 0;
123}
124
125static int sti_console_enabled;
126
127static int omap2_allow_mpu_retention(void)
128{
129	if (!omap2xxx_cm_mpu_retention_allowed())
130		return 0;
131	if (sti_console_enabled)
132		return 0;
133
134	return 1;
135}
136
137static void omap2_enter_mpu_retention(void)
138{
139	const int zero = 0;
140
141	/* The peripherals seem not to be able to wake up the MPU when
142	 * it is in retention mode. */
143	if (omap2_allow_mpu_retention()) {
144		/* REVISIT: These write to reserved bits? */
145		omap_prm_clear_mod_irqs(CORE_MOD, PM_WKST1, ~0);
146		omap_prm_clear_mod_irqs(CORE_MOD, OMAP24XX_PM_WKST2, ~0);
147		omap_prm_clear_mod_irqs(WKUP_MOD, PM_WKST, ~0);
148
149		/* Try to enter MPU retention */
150		pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
151
152	} else {
153		/* Block MPU retention */
154		pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
155	}
156
157	/* WFI */
158	asm("mcr p15, 0, %0, c7, c0, 4" : : "r" (zero) : "memory", "cc");
159
160	pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
161}
162
163static int omap2_can_sleep(void)
164{
165	if (omap2xxx_cm_fclks_active())
166		return 0;
167	if (__clk_is_enabled(osc_ck))
168		return 0;
169	if (omap_dma_running())
170		return 0;
171
172	return 1;
173}
174
175static void omap2_pm_idle(void)
176{
177	if (!omap2_can_sleep()) {
178		if (omap_irq_pending())
179			return;
180		omap2_enter_mpu_retention();
181		return;
182	}
183
184	if (omap_irq_pending())
185		return;
186
187	omap2_enter_full_retention();
188}
189
190static void __init prcm_setup_regs(void)
191{
192	int i, num_mem_banks;
193	struct powerdomain *pwrdm;
194
195	/*
196	 * Enable autoidle
197	 * XXX This should be handled by hwmod code or PRCM init code
198	 */
199	omap2_prm_write_mod_reg(OMAP24XX_AUTOIDLE_MASK, OCP_MOD,
200			  OMAP2_PRCM_SYSCONFIG_OFFSET);
201
202	/*
203	 * Set CORE powerdomain memory banks to retain their contents
204	 * during RETENTION
205	 */
206	num_mem_banks = pwrdm_get_mem_bank_count(core_pwrdm);
207	for (i = 0; i < num_mem_banks; i++)
208		pwrdm_set_mem_retst(core_pwrdm, i, PWRDM_POWER_RET);
209
210	pwrdm_set_logic_retst(core_pwrdm, PWRDM_POWER_RET);
211
212	pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
213
214	/* Force-power down DSP, GFX powerdomains */
215
216	pwrdm = clkdm_get_pwrdm(dsp_clkdm);
217	pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
218
219	pwrdm = clkdm_get_pwrdm(gfx_clkdm);
220	pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
221
222	/* Enable hardware-supervised idle for all clkdms */
223	clkdm_for_each(omap_pm_clkdms_setup, NULL);
224	clkdm_add_wkdep(mpu_clkdm, wkup_clkdm);
225
226	omap_common_suspend_init(omap2_enter_full_retention);
 
 
227
228	/* REVISIT: Configure number of 32 kHz clock cycles for sys_clk
229	 * stabilisation */
230	omap2_prm_write_mod_reg(15 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
231				OMAP2_PRCM_CLKSSETUP_OFFSET);
232
233	/* Configure automatic voltage transition */
234	omap2_prm_write_mod_reg(2 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
235				OMAP2_PRCM_VOLTSETUP_OFFSET);
236	omap2_prm_write_mod_reg(OMAP24XX_AUTO_EXTVOLT_MASK |
237				(0x1 << OMAP24XX_SETOFF_LEVEL_SHIFT) |
238				OMAP24XX_MEMRETCTRL_MASK |
239				(0x1 << OMAP24XX_SETRET_LEVEL_SHIFT) |
240				(0x0 << OMAP24XX_VOLT_LEVEL_SHIFT),
241				OMAP24XX_GR_MOD, OMAP2_PRCM_VOLTCTRL_OFFSET);
242
243	/* Enable wake-up events */
244	omap2_prm_write_mod_reg(OMAP24XX_EN_GPIOS_MASK | OMAP24XX_EN_GPT1_MASK,
245				WKUP_MOD, PM_WKEN);
246
247	/* Enable SYS_CLKEN control when all domains idle */
248	omap2_prm_set_mod_reg_bits(OMAP_AUTOEXTCLKMODE_MASK, OMAP24XX_GR_MOD,
249				   OMAP2_PRCM_CLKSRC_CTRL_OFFSET);
250}
251
252int __init omap2_pm_init(void)
253{
254	u32 l;
255
256	printk(KERN_INFO "Power Management for OMAP2 initializing\n");
257	l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_REVISION_OFFSET);
258	printk(KERN_INFO "PRCM revision %d.%d\n", (l >> 4) & 0x0f, l & 0x0f);
259
260	/* Look up important powerdomains */
261
262	mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
263	if (!mpu_pwrdm)
264		pr_err("PM: mpu_pwrdm not found\n");
265
266	core_pwrdm = pwrdm_lookup("core_pwrdm");
267	if (!core_pwrdm)
268		pr_err("PM: core_pwrdm not found\n");
269
270	/* Look up important clockdomains */
271
272	mpu_clkdm = clkdm_lookup("mpu_clkdm");
273	if (!mpu_clkdm)
274		pr_err("PM: mpu_clkdm not found\n");
275
276	wkup_clkdm = clkdm_lookup("wkup_clkdm");
277	if (!wkup_clkdm)
278		pr_err("PM: wkup_clkdm not found\n");
279
280	dsp_clkdm = clkdm_lookup("dsp_clkdm");
281	if (!dsp_clkdm)
282		pr_err("PM: dsp_clkdm not found\n");
283
284	gfx_clkdm = clkdm_lookup("gfx_clkdm");
285	if (!gfx_clkdm)
286		pr_err("PM: gfx_clkdm not found\n");
287
288
289	osc_ck = clk_get(NULL, "osc_ck");
290	if (IS_ERR(osc_ck)) {
291		printk(KERN_ERR "could not get osc_ck\n");
292		return -ENODEV;
293	}
294
295	if (cpu_is_omap242x()) {
296		emul_ck = clk_get(NULL, "emul_ck");
297		if (IS_ERR(emul_ck)) {
298			printk(KERN_ERR "could not get emul_ck\n");
299			clk_put(osc_ck);
300			return -ENODEV;
301		}
302	}
303
304	prcm_setup_regs();
305
306	/*
307	 * We copy the assembler sleep/wakeup routines to SRAM.
308	 * These routines need to be in SRAM as that's the only
309	 * memory the MPU can see when it wakes up after the entire
310	 * chip enters idle.
311	 */
312	omap2_sram_suspend = omap_sram_push(omap24xx_cpu_suspend,
313					    omap24xx_cpu_suspend_sz);
314
315	arm_pm_idle = omap2_pm_idle;
316
317	return 0;
318}