arch/arm/mach-omap1/pm.c - kernel/msm-4.19 - Gitiles

 /*
  * linux/arch/arm/mach-omap1/pm.c
  *
  * OMAP Power Management Routines
  *
  * Original code for the SA11x0:
  * Copyright (c) 2001 Cliff Brake <cbrake@accelent.com>
  *
  * Modified for the PXA250 by Nicolas Pitre:
  * Copyright (c) 2002 Monta Vista Software, Inc.
  *
  * Modified for the OMAP1510 by David Singleton:
  * Copyright (c) 2002 Monta Vista Software, Inc.
  *
  * Cleanup 2004 for OMAP1510/1610 by Dirk Behme <dirk.behme@de.bosch.com>
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License as published by the
  * Free Software Foundation; either version 2 of the License, or (at your
  * option) any later version.
  *
  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
  * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
  * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  * You should have received a copy of the GNU General Public License along
  * with this program; if not, write to the Free Software Foundation, Inc.,
  * 675 Mass Ave, Cambridge, MA 02139, USA.
  */

 #include <linux/suspend.h>
 #include <linux/sched.h>
 #include <linux/proc_fs.h>
 #include <linux/interrupt.h>
 #include <linux/sysfs.h>
 #include <linux/module.h>
 #include <linux/io.h>

 #include <asm/irq.h>
 #include <asm/atomic.h>
 #include <asm/mach/time.h>
 #include <asm/mach/irq.h>

 #include <mach/cpu.h>
 #include <mach/irqs.h>
 #include <mach/clock.h>
 #include <mach/sram.h>
 #include <mach/tc.h>
 #include <mach/mux.h>
 #include <mach/dma.h>
 #include <mach/dmtimer.h>

 #include "pm.h"

 static unsigned int arm_sleep_save[ARM_SLEEP_SAVE_SIZE];
 static unsigned short dsp_sleep_save[DSP_SLEEP_SAVE_SIZE];
 static unsigned short ulpd_sleep_save[ULPD_SLEEP_SAVE_SIZE];
 static unsigned int mpui730_sleep_save[MPUI730_SLEEP_SAVE_SIZE];
 static unsigned int mpui1510_sleep_save[MPUI1510_SLEEP_SAVE_SIZE];
 static unsigned int mpui1610_sleep_save[MPUI1610_SLEEP_SAVE_SIZE];

 #ifdef CONFIG_OMAP_32K_TIMER

 static unsigned short enable_dyn_sleep = 1;

 static ssize_t idle_show(struct kobject *kobj, struct kobj_attribute *attr,
 			 char *buf)
 {
 	return sprintf(buf, "%hu\n", enable_dyn_sleep);
 }

 static ssize_t idle_store(struct kobject *kobj, struct kobj_attribute *attr,
 			  const char * buf, size_t n)
 {
 	unsigned short value;
 	if (sscanf(buf, "%hu", &value) != 1 ||
 	    (value != 0 && value != 1)) {
 		printk(KERN_ERR "idle_sleep_store: Invalid value\n");
 		return -EINVAL;
 	}
 	enable_dyn_sleep = value;
 	return n;
 }

 static struct kobj_attribute sleep_while_idle_attr =
 	__ATTR(sleep_while_idle, 0644, idle_show, idle_store);

 #endif

 static void (*omap_sram_suspend)(unsigned long r0, unsigned long r1) = NULL;

 /*
  * Let's power down on idle, but only if we are really
  * idle, because once we start down the path of
  * going idle we continue to do idle even if we get
  * a clock tick interrupt . .
  */
 void omap1_pm_idle(void)
 {
 	extern __u32 arm_idlect1_mask;
 	__u32 use_idlect1 = arm_idlect1_mask;
 	int do_sleep = 0;

 	local_irq_disable();
 	local_fiq_disable();
 	if (need_resched()) {
 		local_fiq_enable();
 		local_irq_enable();
 		return;
 	}

 #ifdef CONFIG_OMAP_MPU_TIMER
 #warning Enable 32kHz OS timer in order to allow sleep states in idle
 	use_idlect1 = use_idlect1 & ~(1 << 9);
 #else

 	while (enable_dyn_sleep) {

 #ifdef CONFIG_CBUS_TAHVO_USB
 		extern int vbus_active;
 		/* Clock requirements? */
 		if (vbus_active)
 			break;
 #endif
 		do_sleep = 1;
 		break;
 	}

 #endif

 #ifdef CONFIG_OMAP_DM_TIMER
 	use_idlect1 = omap_dm_timer_modify_idlect_mask(use_idlect1);
 #endif

 	if (omap_dma_running())
 		use_idlect1 &= ~(1 << 6);

 	/* We should be able to remove the do_sleep variable and multiple
 	 * tests above as soon as drivers, timer and DMA code have been fixed.
 	 * Even the sleep block count should become obsolete. */
 	if ((use_idlect1 != ~0) || !do_sleep) {

 		__u32 saved_idlect1 = omap_readl(ARM_IDLECT1);
 		if (cpu_is_omap15xx())
 			use_idlect1 &= OMAP1510_BIG_SLEEP_REQUEST;
 		else
 			use_idlect1 &= OMAP1610_IDLECT1_SLEEP_VAL;
 		omap_writel(use_idlect1, ARM_IDLECT1);
 		__asm__ volatile ("mcr	p15, 0, r0, c7, c0, 4");
 		omap_writel(saved_idlect1, ARM_IDLECT1);

 		local_fiq_enable();
 		local_irq_enable();
 		return;
 	}
 	omap_sram_suspend(omap_readl(ARM_IDLECT1),
 			  omap_readl(ARM_IDLECT2));

 	local_fiq_enable();
 	local_irq_enable();
 }

 /*
  * Configuration of the wakeup event is board specific. For the
  * moment we put it into this helper function. Later it may move
  * to board specific files.
  */
 static void omap_pm_wakeup_setup(void)
 {
 	u32 level1_wake = 0;
 	u32 level2_wake = OMAP_IRQ_BIT(INT_UART2);

 	/*
 	 * Turn off all interrupts except GPIO bank 1, L1-2nd level cascade,
 	 * and the L2 wakeup interrupts: keypad and UART2. Note that the
 	 * drivers must still separately call omap_set_gpio_wakeup() to
 	 * wake up to a GPIO interrupt.
 	 */
 	if (cpu_is_omap7xx())
 		level1_wake = OMAP_IRQ_BIT(INT_7XX_GPIO_BANK1) |
 			OMAP_IRQ_BIT(INT_7XX_IH2_IRQ);
 	else if (cpu_is_omap15xx())
 		level1_wake = OMAP_IRQ_BIT(INT_GPIO_BANK1) |
 			OMAP_IRQ_BIT(INT_1510_IH2_IRQ);
 	else if (cpu_is_omap16xx())
 		level1_wake = OMAP_IRQ_BIT(INT_GPIO_BANK1) |
 			OMAP_IRQ_BIT(INT_1610_IH2_IRQ);

 	omap_writel(~level1_wake, OMAP_IH1_MIR);

 	if (cpu_is_omap7xx()) {
 		omap_writel(~level2_wake, OMAP_IH2_0_MIR);
 		omap_writel(~(OMAP_IRQ_BIT(INT_7XX_WAKE_UP_REQ) |
 				OMAP_IRQ_BIT(INT_7XX_MPUIO_KEYPAD)),
 				OMAP_IH2_1_MIR);
 	} else if (cpu_is_omap15xx()) {
 		level2_wake |= OMAP_IRQ_BIT(INT_KEYBOARD);
 		omap_writel(~level2_wake,  OMAP_IH2_MIR);
 	} else if (cpu_is_omap16xx()) {
 		level2_wake |= OMAP_IRQ_BIT(INT_KEYBOARD);
 		omap_writel(~level2_wake, OMAP_IH2_0_MIR);

 		/* INT_1610_WAKE_UP_REQ is needed for GPIO wakeup... */
 		omap_writel(~OMAP_IRQ_BIT(INT_1610_WAKE_UP_REQ),
 			    OMAP_IH2_1_MIR);
 		omap_writel(~0x0, OMAP_IH2_2_MIR);
 		omap_writel(~0x0, OMAP_IH2_3_MIR);
 	}

 	/*  New IRQ agreement, recalculate in cascade order */
 	omap_writel(1, OMAP_IH2_CONTROL);
 	omap_writel(1, OMAP_IH1_CONTROL);
 }

 #define EN_DSPCK	13	/* ARM_CKCTL */
 #define EN_APICK	6	/* ARM_IDLECT2 */
 #define DSP_EN		1	/* ARM_RSTCT1 */

 void omap1_pm_suspend(void)
 {
 	unsigned long arg0 = 0, arg1 = 0;

 	printk(KERN_INFO "PM: OMAP%x is trying to enter deep sleep...\n",
 		omap_rev());

 	omap_serial_wake_trigger(1);

 	if (!cpu_is_omap15xx())
 		omap_writew(0xffff, ULPD_SOFT_DISABLE_REQ_REG);

 	/*
 	 * Step 1: turn off interrupts (FIXME: NOTE: already disabled)
 	 */

 	local_irq_disable();
 	local_fiq_disable();

 	/*
 	 * Step 2: save registers
 	 *
 	 * The omap is a strange/beautiful device. The caches, memory
 	 * and register state are preserved across power saves.
 	 * We have to save and restore very little register state to
 	 * idle the omap.
          *
 	 * Save interrupt, MPUI, ARM and UPLD control registers.
 	 */

 	if (cpu_is_omap7xx()) {
 		MPUI730_SAVE(OMAP_IH1_MIR);
 		MPUI730_SAVE(OMAP_IH2_0_MIR);
 		MPUI730_SAVE(OMAP_IH2_1_MIR);
 		MPUI730_SAVE(MPUI_CTRL);
 		MPUI730_SAVE(MPUI_DSP_BOOT_CONFIG);
 		MPUI730_SAVE(MPUI_DSP_API_CONFIG);
 		MPUI730_SAVE(EMIFS_CONFIG);
 		MPUI730_SAVE(EMIFF_SDRAM_CONFIG);

 	} else if (cpu_is_omap15xx()) {
 		MPUI1510_SAVE(OMAP_IH1_MIR);
 		MPUI1510_SAVE(OMAP_IH2_MIR);
 		MPUI1510_SAVE(MPUI_CTRL);
 		MPUI1510_SAVE(MPUI_DSP_BOOT_CONFIG);
 		MPUI1510_SAVE(MPUI_DSP_API_CONFIG);
 		MPUI1510_SAVE(EMIFS_CONFIG);
 		MPUI1510_SAVE(EMIFF_SDRAM_CONFIG);
 	} else if (cpu_is_omap16xx()) {
 		MPUI1610_SAVE(OMAP_IH1_MIR);
 		MPUI1610_SAVE(OMAP_IH2_0_MIR);
 		MPUI1610_SAVE(OMAP_IH2_1_MIR);
 		MPUI1610_SAVE(OMAP_IH2_2_MIR);
 		MPUI1610_SAVE(OMAP_IH2_3_MIR);
 		MPUI1610_SAVE(MPUI_CTRL);
 		MPUI1610_SAVE(MPUI_DSP_BOOT_CONFIG);
 		MPUI1610_SAVE(MPUI_DSP_API_CONFIG);
 		MPUI1610_SAVE(EMIFS_CONFIG);
 		MPUI1610_SAVE(EMIFF_SDRAM_CONFIG);
 	}

 	ARM_SAVE(ARM_CKCTL);
 	ARM_SAVE(ARM_IDLECT1);
 	ARM_SAVE(ARM_IDLECT2);
 	if (!(cpu_is_omap15xx()))
 		ARM_SAVE(ARM_IDLECT3);
 	ARM_SAVE(ARM_EWUPCT);
 	ARM_SAVE(ARM_RSTCT1);
 	ARM_SAVE(ARM_RSTCT2);
 	ARM_SAVE(ARM_SYSST);
 	ULPD_SAVE(ULPD_CLOCK_CTRL);
 	ULPD_SAVE(ULPD_STATUS_REQ);

 	/* (Step 3 removed - we now allow deep sleep by default) */

 	/*
 	 * Step 4: OMAP DSP Shutdown
 	 */

 	/* stop DSP */
 	omap_writew(omap_readw(ARM_RSTCT1) & ~(1 << DSP_EN), ARM_RSTCT1);

 		/* shut down dsp_ck */
 	if (!cpu_is_omap7xx())
 		omap_writew(omap_readw(ARM_CKCTL) & ~(1 << EN_DSPCK), ARM_CKCTL);

 	/* temporarily enabling api_ck to access DSP registers */
 	omap_writew(omap_readw(ARM_IDLECT2) | 1 << EN_APICK, ARM_IDLECT2);

 	/* save DSP registers */
 	DSP_SAVE(DSP_IDLECT2);

 	/* Stop all DSP domain clocks */
 	__raw_writew(0, DSP_IDLECT2);

 	/*
 	 * Step 5: Wakeup Event Setup
 	 */

 	omap_pm_wakeup_setup();

 	/*
 	 * Step 6: ARM and Traffic controller shutdown
 	 */

 	/* disable ARM watchdog */
 	omap_writel(0x00F5, OMAP_WDT_TIMER_MODE);
 	omap_writel(0x00A0, OMAP_WDT_TIMER_MODE);

 	/*
 	 * Step 6b: ARM and Traffic controller shutdown
 	 *
 	 * Step 6 continues here. Prepare jump to power management
 	 * assembly code in internal SRAM.
 	 *
 	 * Since the omap_cpu_suspend routine has been copied to
 	 * SRAM, we'll do an indirect procedure call to it and pass the
 	 * contents of arm_idlect1 and arm_idlect2 so it can restore
 	 * them when it wakes up and it will return.
 	 */

 	arg0 = arm_sleep_save[ARM_SLEEP_SAVE_ARM_IDLECT1];
 	arg1 = arm_sleep_save[ARM_SLEEP_SAVE_ARM_IDLECT2];

 	/*
 	 * Step 6c: ARM and Traffic controller shutdown
 	 *
 	 * Jump to assembly code. The processor will stay there
 	 * until wake up.
 	 */
 	omap_sram_suspend(arg0, arg1);

 	/*
 	 * If we are here, processor is woken up!
 	 */

 	/*
 	 * Restore DSP clocks
 	 */

 	/* again temporarily enabling api_ck to access DSP registers */
 	omap_writew(omap_readw(ARM_IDLECT2) | 1 << EN_APICK, ARM_IDLECT2);

 	/* Restore DSP domain clocks */
 	DSP_RESTORE(DSP_IDLECT2);

 	/*
 	 * Restore ARM state, except ARM_IDLECT1/2 which omap_cpu_suspend did
 	 */

 	if (!(cpu_is_omap15xx()))
 		ARM_RESTORE(ARM_IDLECT3);
 	ARM_RESTORE(ARM_CKCTL);
 	ARM_RESTORE(ARM_EWUPCT);
 	ARM_RESTORE(ARM_RSTCT1);
 	ARM_RESTORE(ARM_RSTCT2);
 	ARM_RESTORE(ARM_SYSST);
 	ULPD_RESTORE(ULPD_CLOCK_CTRL);
 	ULPD_RESTORE(ULPD_STATUS_REQ);

 	if (cpu_is_omap7xx()) {
 		MPUI730_RESTORE(EMIFS_CONFIG);
 		MPUI730_RESTORE(EMIFF_SDRAM_CONFIG);
 		MPUI730_RESTORE(OMAP_IH1_MIR);
 		MPUI730_RESTORE(OMAP_IH2_0_MIR);
 		MPUI730_RESTORE(OMAP_IH2_1_MIR);
 	} else if (cpu_is_omap15xx()) {
 		MPUI1510_RESTORE(MPUI_CTRL);
 		MPUI1510_RESTORE(MPUI_DSP_BOOT_CONFIG);
 		MPUI1510_RESTORE(MPUI_DSP_API_CONFIG);
 		MPUI1510_RESTORE(EMIFS_CONFIG);
 		MPUI1510_RESTORE(EMIFF_SDRAM_CONFIG);
 		MPUI1510_RESTORE(OMAP_IH1_MIR);
 		MPUI1510_RESTORE(OMAP_IH2_MIR);
 	} else if (cpu_is_omap16xx()) {
 		MPUI1610_RESTORE(MPUI_CTRL);
 		MPUI1610_RESTORE(MPUI_DSP_BOOT_CONFIG);
 		MPUI1610_RESTORE(MPUI_DSP_API_CONFIG);
 		MPUI1610_RESTORE(EMIFS_CONFIG);
 		MPUI1610_RESTORE(EMIFF_SDRAM_CONFIG);

 		MPUI1610_RESTORE(OMAP_IH1_MIR);
 		MPUI1610_RESTORE(OMAP_IH2_0_MIR);
 		MPUI1610_RESTORE(OMAP_IH2_1_MIR);
 		MPUI1610_RESTORE(OMAP_IH2_2_MIR);
 		MPUI1610_RESTORE(OMAP_IH2_3_MIR);
 	}

 	if (!cpu_is_omap15xx())
 		omap_writew(0, ULPD_SOFT_DISABLE_REQ_REG);

 	/*
 	 * Re-enable interrupts
 	 */

 	local_irq_enable();
 	local_fiq_enable();

 	omap_serial_wake_trigger(0);

 	printk(KERN_INFO "PM: OMAP%x is re-starting from deep sleep...\n",
 		omap_rev());
 }

 #if defined(DEBUG) && defined(CONFIG_PROC_FS)
 static int g_read_completed;

 /*
  * Read system PM registers for debugging
  */
 static int omap_pm_read_proc(
 	char *page_buffer,
 	char **my_first_byte,
 	off_t virtual_start,
 	int length,
 	int *eof,
 	void *data)
 {
 	int my_buffer_offset = 0;
 	char * const my_base = page_buffer;

 	ARM_SAVE(ARM_CKCTL);
 	ARM_SAVE(ARM_IDLECT1);
 	ARM_SAVE(ARM_IDLECT2);
 	if (!(cpu_is_omap15xx()))
 		ARM_SAVE(ARM_IDLECT3);
 	ARM_SAVE(ARM_EWUPCT);
 	ARM_SAVE(ARM_RSTCT1);
 	ARM_SAVE(ARM_RSTCT2);
 	ARM_SAVE(ARM_SYSST);

 	ULPD_SAVE(ULPD_IT_STATUS);
 	ULPD_SAVE(ULPD_CLOCK_CTRL);
 	ULPD_SAVE(ULPD_SOFT_REQ);
 	ULPD_SAVE(ULPD_STATUS_REQ);
 	ULPD_SAVE(ULPD_DPLL_CTRL);
 	ULPD_SAVE(ULPD_POWER_CTRL);

 	if (cpu_is_omap7xx()) {
 		MPUI730_SAVE(MPUI_CTRL);
 		MPUI730_SAVE(MPUI_DSP_STATUS);
 		MPUI730_SAVE(MPUI_DSP_BOOT_CONFIG);
 		MPUI730_SAVE(MPUI_DSP_API_CONFIG);
 		MPUI730_SAVE(EMIFF_SDRAM_CONFIG);
 		MPUI730_SAVE(EMIFS_CONFIG);
 	} else if (cpu_is_omap15xx()) {
 		MPUI1510_SAVE(MPUI_CTRL);
 		MPUI1510_SAVE(MPUI_DSP_STATUS);
 		MPUI1510_SAVE(MPUI_DSP_BOOT_CONFIG);
 		MPUI1510_SAVE(MPUI_DSP_API_CONFIG);
 		MPUI1510_SAVE(EMIFF_SDRAM_CONFIG);
 		MPUI1510_SAVE(EMIFS_CONFIG);
 	} else if (cpu_is_omap16xx()) {
 		MPUI1610_SAVE(MPUI_CTRL);
 		MPUI1610_SAVE(MPUI_DSP_STATUS);
 		MPUI1610_SAVE(MPUI_DSP_BOOT_CONFIG);
 		MPUI1610_SAVE(MPUI_DSP_API_CONFIG);
 		MPUI1610_SAVE(EMIFF_SDRAM_CONFIG);
 		MPUI1610_SAVE(EMIFS_CONFIG);
 	}

 	if (virtual_start == 0) {
 		g_read_completed = 0;

 		my_buffer_offset += sprintf(my_base + my_buffer_offset,
 		   "ARM_CKCTL_REG:            0x%-8x     \n"
 		   "ARM_IDLECT1_REG:          0x%-8x     \n"
 		   "ARM_IDLECT2_REG:          0x%-8x     \n"
 		   "ARM_IDLECT3_REG:	      0x%-8x     \n"
 		   "ARM_EWUPCT_REG:           0x%-8x     \n"
 		   "ARM_RSTCT1_REG:           0x%-8x     \n"
 		   "ARM_RSTCT2_REG:           0x%-8x     \n"
 		   "ARM_SYSST_REG:            0x%-8x     \n"
 		   "ULPD_IT_STATUS_REG:       0x%-4x     \n"
 		   "ULPD_CLOCK_CTRL_REG:      0x%-4x     \n"
 		   "ULPD_SOFT_REQ_REG:        0x%-4x     \n"
 		   "ULPD_DPLL_CTRL_REG:       0x%-4x     \n"
 		   "ULPD_STATUS_REQ_REG:      0x%-4x     \n"
 		   "ULPD_POWER_CTRL_REG:      0x%-4x     \n",
 		   ARM_SHOW(ARM_CKCTL),
 		   ARM_SHOW(ARM_IDLECT1),
 		   ARM_SHOW(ARM_IDLECT2),
 		   ARM_SHOW(ARM_IDLECT3),
 		   ARM_SHOW(ARM_EWUPCT),
 		   ARM_SHOW(ARM_RSTCT1),
 		   ARM_SHOW(ARM_RSTCT2),
 		   ARM_SHOW(ARM_SYSST),
 		   ULPD_SHOW(ULPD_IT_STATUS),
 		   ULPD_SHOW(ULPD_CLOCK_CTRL),
 		   ULPD_SHOW(ULPD_SOFT_REQ),
 		   ULPD_SHOW(ULPD_DPLL_CTRL),
 		   ULPD_SHOW(ULPD_STATUS_REQ),
 		   ULPD_SHOW(ULPD_POWER_CTRL));

 		if (cpu_is_omap7xx()) {
 			my_buffer_offset += sprintf(my_base + my_buffer_offset,
 			   "MPUI730_CTRL_REG	     0x%-8x \n"
 			   "MPUI730_DSP_STATUS_REG:      0x%-8x \n"
 			   "MPUI730_DSP_BOOT_CONFIG_REG: 0x%-8x \n"
 			   "MPUI730_DSP_API_CONFIG_REG:  0x%-8x \n"
 			   "MPUI730_SDRAM_CONFIG_REG:    0x%-8x \n"
 			   "MPUI730_EMIFS_CONFIG_REG:    0x%-8x \n",
 			   MPUI730_SHOW(MPUI_CTRL),
 			   MPUI730_SHOW(MPUI_DSP_STATUS),
 			   MPUI730_SHOW(MPUI_DSP_BOOT_CONFIG),
 			   MPUI730_SHOW(MPUI_DSP_API_CONFIG),
 			   MPUI730_SHOW(EMIFF_SDRAM_CONFIG),
 			   MPUI730_SHOW(EMIFS_CONFIG));
 		} else if (cpu_is_omap15xx()) {
 			my_buffer_offset += sprintf(my_base + my_buffer_offset,
 			   "MPUI1510_CTRL_REG             0x%-8x \n"
 			   "MPUI1510_DSP_STATUS_REG:      0x%-8x \n"
 			   "MPUI1510_DSP_BOOT_CONFIG_REG: 0x%-8x \n"
 			   "MPUI1510_DSP_API_CONFIG_REG:  0x%-8x \n"
 			   "MPUI1510_SDRAM_CONFIG_REG:    0x%-8x \n"
 			   "MPUI1510_EMIFS_CONFIG_REG:    0x%-8x \n",
 			   MPUI1510_SHOW(MPUI_CTRL),
 			   MPUI1510_SHOW(MPUI_DSP_STATUS),
 			   MPUI1510_SHOW(MPUI_DSP_BOOT_CONFIG),
 			   MPUI1510_SHOW(MPUI_DSP_API_CONFIG),
 			   MPUI1510_SHOW(EMIFF_SDRAM_CONFIG),
 			   MPUI1510_SHOW(EMIFS_CONFIG));
 		} else if (cpu_is_omap16xx()) {
 			my_buffer_offset += sprintf(my_base + my_buffer_offset,
 			   "MPUI1610_CTRL_REG             0x%-8x \n"
 			   "MPUI1610_DSP_STATUS_REG:      0x%-8x \n"
 			   "MPUI1610_DSP_BOOT_CONFIG_REG: 0x%-8x \n"
 			   "MPUI1610_DSP_API_CONFIG_REG:  0x%-8x \n"
 			   "MPUI1610_SDRAM_CONFIG_REG:    0x%-8x \n"
 			   "MPUI1610_EMIFS_CONFIG_REG:    0x%-8x \n",
 			   MPUI1610_SHOW(MPUI_CTRL),
 			   MPUI1610_SHOW(MPUI_DSP_STATUS),
 			   MPUI1610_SHOW(MPUI_DSP_BOOT_CONFIG),
 			   MPUI1610_SHOW(MPUI_DSP_API_CONFIG),
 			   MPUI1610_SHOW(EMIFF_SDRAM_CONFIG),
 			   MPUI1610_SHOW(EMIFS_CONFIG));
 		}

 		g_read_completed++;
 	} else if (g_read_completed >= 1) {
 		 *eof = 1;
 		 return 0;
 	}
 	g_read_completed++;

 	*my_first_byte = page_buffer;
 	return  my_buffer_offset;
 }

 static void omap_pm_init_proc(void)
 {
 	struct proc_dir_entry *entry;

 	entry = create_proc_read_entry("driver/omap_pm",
 				       S_IWUSR | S_IRUGO, NULL,
 				       omap_pm_read_proc, NULL);
 }

 #endif /* DEBUG && CONFIG_PROC_FS */

 static void (*saved_idle)(void) = NULL;

 /*
  *	omap_pm_prepare - Do preliminary suspend work.
  *
  */
 static int omap_pm_prepare(void)
 {
 	/* We cannot sleep in idle until we have resumed */
 	saved_idle = pm_idle;
 	pm_idle = NULL;

 	return 0;
 }


 /*
  *	omap_pm_enter - Actually enter a sleep state.
  *	@state:		State we're entering.
  *
  */

 static int omap_pm_enter(suspend_state_t state)
 {
 	switch (state)
 	{
 	case PM_SUSPEND_STANDBY:
 	case PM_SUSPEND_MEM:
 		omap1_pm_suspend();
 		break;
 	default:
 		return -EINVAL;
 	}

 	return 0;
 }


 /**
  *	omap_pm_finish - Finish up suspend sequence.
  *
  *	This is called after we wake back up (or if entering the sleep state
  *	failed).
  */

 static void omap_pm_finish(void)
 {
 	pm_idle = saved_idle;
 }


 static irqreturn_t omap_wakeup_interrupt(int irq, void *dev)
 {
 	return IRQ_HANDLED;
 }

 static struct irqaction omap_wakeup_irq = {
 	.name		= "peripheral wakeup",
 	.flags		= IRQF_DISABLED,
 	.handler	= omap_wakeup_interrupt
 };


 static struct platform_suspend_ops omap_pm_ops ={
 	.prepare	= omap_pm_prepare,
 	.enter		= omap_pm_enter,
 	.finish		= omap_pm_finish,
 	.valid		= suspend_valid_only_mem,
 };

 static int __init omap_pm_init(void)
 {

 #ifdef CONFIG_OMAP_32K_TIMER
 	int error;
 #endif

 	printk("Power Management for TI OMAP.\n");

 	/*
 	 * We copy the assembler sleep/wakeup routines to SRAM.
 	 * These routines need to be in SRAM as that's the only
 	 * memory the MPU can see when it wakes up.
 	 */
 	if (cpu_is_omap7xx()) {
 		omap_sram_suspend = omap_sram_push(omap730_cpu_suspend,
 						   omap730_cpu_suspend_sz);
 	} else if (cpu_is_omap15xx()) {
 		omap_sram_suspend = omap_sram_push(omap1510_cpu_suspend,
 						   omap1510_cpu_suspend_sz);
 	} else if (cpu_is_omap16xx()) {
 		omap_sram_suspend = omap_sram_push(omap1610_cpu_suspend,
 						   omap1610_cpu_suspend_sz);
 	}

 	if (omap_sram_suspend == NULL) {
 		printk(KERN_ERR "PM not initialized: Missing SRAM support\n");
 		return -ENODEV;
 	}

 	pm_idle = omap1_pm_idle;

 	if (cpu_is_omap7xx())
 		setup_irq(INT_7XX_WAKE_UP_REQ, &omap_wakeup_irq);
 	else if (cpu_is_omap16xx())
 		setup_irq(INT_1610_WAKE_UP_REQ, &omap_wakeup_irq);

 	/* Program new power ramp-up time
 	 * (0 for most boards since we don't lower voltage when in deep sleep)
 	 */
 	omap_writew(ULPD_SETUP_ANALOG_CELL_3_VAL, ULPD_SETUP_ANALOG_CELL_3);

 	/* Setup ULPD POWER_CTRL_REG - enter deep sleep whenever possible */
 	omap_writew(ULPD_POWER_CTRL_REG_VAL, ULPD_POWER_CTRL);

 	/* Configure IDLECT3 */
 	if (cpu_is_omap7xx())
 		omap_writel(OMAP730_IDLECT3_VAL, OMAP730_IDLECT3);
 	else if (cpu_is_omap16xx())
 		omap_writel(OMAP1610_IDLECT3_VAL, OMAP1610_IDLECT3);

 	suspend_set_ops(&omap_pm_ops);

 #if defined(DEBUG) && defined(CONFIG_PROC_FS)
 	omap_pm_init_proc();
 #endif

 #ifdef CONFIG_OMAP_32K_TIMER
 	error = sysfs_create_file(power_kobj, &sleep_while_idle_attr.attr);
 	if (error)
 		printk(KERN_ERR "sysfs_create_file failed: %d\n", error);
 #endif

 	if (cpu_is_omap16xx()) {
 		/* configure LOW_PWR pin */
 		omap_cfg_reg(T20_1610_LOW_PWR);
 	}

 	return 0;
 }
 __initcall(omap_pm_init);
	/*
	* linux/arch/arm/mach-omap1/pm.c
	*
	* OMAP Power Management Routines
	*
	* Original code for the SA11x0:
	* Copyright (c) 2001 Cliff Brake <cbrake@accelent.com>
	*
	* Modified for the PXA250 by Nicolas Pitre:
	* Copyright (c) 2002 Monta Vista Software, Inc.
	*
	* Modified for the OMAP1510 by David Singleton:
	* Copyright (c) 2002 Monta Vista Software, Inc.
	*
	* Cleanup 2004 for OMAP1510/1610 by Dirk Behme <dirk.behme@de.bosch.com>
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License as published by the
	* Free Software Foundation; either version 2 of the License, or (at your
	* option) any later version.
	*
	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
	* NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
	* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
	* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*
	* You should have received a copy of the GNU General Public License along
	* with this program; if not, write to the Free Software Foundation, Inc.,
	* 675 Mass Ave, Cambridge, MA 02139, USA.
	*/

	#include <linux/suspend.h>
	#include <linux/sched.h>
	#include <linux/proc_fs.h>
	#include <linux/interrupt.h>
	#include <linux/sysfs.h>
	#include <linux/module.h>
	#include <linux/io.h>

	#include <asm/irq.h>
	#include <asm/atomic.h>
	#include <asm/mach/time.h>
	#include <asm/mach/irq.h>

	#include <mach/cpu.h>
	#include <mach/irqs.h>
	#include <mach/clock.h>
	#include <mach/sram.h>
	#include <mach/tc.h>
	#include <mach/mux.h>
	#include <mach/dma.h>
	#include <mach/dmtimer.h>

	#include "pm.h"

	static unsigned int arm_sleep_save[ARM_SLEEP_SAVE_SIZE];
	static unsigned short dsp_sleep_save[DSP_SLEEP_SAVE_SIZE];
	static unsigned short ulpd_sleep_save[ULPD_SLEEP_SAVE_SIZE];
	static unsigned int mpui730_sleep_save[MPUI730_SLEEP_SAVE_SIZE];
	static unsigned int mpui1510_sleep_save[MPUI1510_SLEEP_SAVE_SIZE];
	static unsigned int mpui1610_sleep_save[MPUI1610_SLEEP_SAVE_SIZE];

	#ifdef CONFIG_OMAP_32K_TIMER

	static unsigned short enable_dyn_sleep = 1;

	static ssize_t idle_show(struct kobject kobj, struct kobj_attribute attr,
	char *buf)
	{
	return sprintf(buf, "%hu\n", enable_dyn_sleep);
	}

	static ssize_t idle_store(struct kobject kobj, struct kobj_attribute attr,
	const char * buf, size_t n)
	{
	unsigned short value;
	if (sscanf(buf, "%hu", &value) != 1 \|\|
	(value != 0 && value != 1)) {
	printk(KERN_ERR "idle_sleep_store: Invalid value\n");
	return -EINVAL;
	}
	enable_dyn_sleep = value;
	return n;
	}

	static struct kobj_attribute sleep_while_idle_attr =
	__ATTR(sleep_while_idle, 0644, idle_show, idle_store);

	#endif

	static void (*omap_sram_suspend)(unsigned long r0, unsigned long r1) = NULL;

	/*
	* Let's power down on idle, but only if we are really
	* idle, because once we start down the path of
	* going idle we continue to do idle even if we get
	* a clock tick interrupt . .
	*/
	void omap1_pm_idle(void)
	{
	extern __u32 arm_idlect1_mask;
	__u32 use_idlect1 = arm_idlect1_mask;
	int do_sleep = 0;

	local_irq_disable();
	local_fiq_disable();
	if (need_resched()) {
	local_fiq_enable();
	local_irq_enable();
	return;
	}

	#ifdef CONFIG_OMAP_MPU_TIMER
	#warning Enable 32kHz OS timer in order to allow sleep states in idle
	use_idlect1 = use_idlect1 & ~(1 << 9);
	#else

	while (enable_dyn_sleep) {

	#ifdef CONFIG_CBUS_TAHVO_USB
	extern int vbus_active;
	/* Clock requirements? */
	if (vbus_active)
	break;
	#endif
	do_sleep = 1;
	break;
	}

	#endif

	#ifdef CONFIG_OMAP_DM_TIMER
	use_idlect1 = omap_dm_timer_modify_idlect_mask(use_idlect1);
	#endif

	if (omap_dma_running())
	use_idlect1 &= ~(1 << 6);

	/* We should be able to remove the do_sleep variable and multiple
	* tests above as soon as drivers, timer and DMA code have been fixed.
	* Even the sleep block count should become obsolete. */
	if ((use_idlect1 != ~0) \|\| !do_sleep) {

	__u32 saved_idlect1 = omap_readl(ARM_IDLECT1);
	if (cpu_is_omap15xx())
	use_idlect1 &= OMAP1510_BIG_SLEEP_REQUEST;
	else
	use_idlect1 &= OMAP1610_IDLECT1_SLEEP_VAL;
	omap_writel(use_idlect1, ARM_IDLECT1);
	__asm__ volatile ("mcr p15, 0, r0, c7, c0, 4");
	omap_writel(saved_idlect1, ARM_IDLECT1);

	local_fiq_enable();
	local_irq_enable();
	return;
	}
	omap_sram_suspend(omap_readl(ARM_IDLECT1),
	omap_readl(ARM_IDLECT2));

	local_fiq_enable();
	local_irq_enable();
	}

	/*
	* Configuration of the wakeup event is board specific. For the
	* moment we put it into this helper function. Later it may move
	* to board specific files.
	*/
	static void omap_pm_wakeup_setup(void)
	{
	u32 level1_wake = 0;
	u32 level2_wake = OMAP_IRQ_BIT(INT_UART2);

	/*
	* Turn off all interrupts except GPIO bank 1, L1-2nd level cascade,
	* and the L2 wakeup interrupts: keypad and UART2. Note that the
	* drivers must still separately call omap_set_gpio_wakeup() to
	* wake up to a GPIO interrupt.
	*/
	if (cpu_is_omap7xx())
	level1_wake = OMAP_IRQ_BIT(INT_7XX_GPIO_BANK1) \|
	OMAP_IRQ_BIT(INT_7XX_IH2_IRQ);
	else if (cpu_is_omap15xx())
	level1_wake = OMAP_IRQ_BIT(INT_GPIO_BANK1) \|
	OMAP_IRQ_BIT(INT_1510_IH2_IRQ);
	else if (cpu_is_omap16xx())
	level1_wake = OMAP_IRQ_BIT(INT_GPIO_BANK1) \|
	OMAP_IRQ_BIT(INT_1610_IH2_IRQ);

	omap_writel(~level1_wake, OMAP_IH1_MIR);

	if (cpu_is_omap7xx()) {
	omap_writel(~level2_wake, OMAP_IH2_0_MIR);
	omap_writel(~(OMAP_IRQ_BIT(INT_7XX_WAKE_UP_REQ) \|
	OMAP_IRQ_BIT(INT_7XX_MPUIO_KEYPAD)),
	OMAP_IH2_1_MIR);
	} else if (cpu_is_omap15xx()) {
	level2_wake \|= OMAP_IRQ_BIT(INT_KEYBOARD);
	omap_writel(~level2_wake, OMAP_IH2_MIR);
	} else if (cpu_is_omap16xx()) {
	level2_wake \|= OMAP_IRQ_BIT(INT_KEYBOARD);
	omap_writel(~level2_wake, OMAP_IH2_0_MIR);

	/* INT_1610_WAKE_UP_REQ is needed for GPIO wakeup... */
	omap_writel(~OMAP_IRQ_BIT(INT_1610_WAKE_UP_REQ),
	OMAP_IH2_1_MIR);
	omap_writel(~0x0, OMAP_IH2_2_MIR);
	omap_writel(~0x0, OMAP_IH2_3_MIR);
	}

	/* New IRQ agreement, recalculate in cascade order */
	omap_writel(1, OMAP_IH2_CONTROL);
	omap_writel(1, OMAP_IH1_CONTROL);
	}

	#define EN_DSPCK 13 /* ARM_CKCTL */
	#define EN_APICK 6 /* ARM_IDLECT2 */
	#define DSP_EN 1 /* ARM_RSTCT1 */

	void omap1_pm_suspend(void)
	{
	unsigned long arg0 = 0, arg1 = 0;

	printk(KERN_INFO "PM: OMAP%x is trying to enter deep sleep...\n",
	omap_rev());

	omap_serial_wake_trigger(1);

	if (!cpu_is_omap15xx())
	omap_writew(0xffff, ULPD_SOFT_DISABLE_REQ_REG);

	/*
	* Step 1: turn off interrupts (FIXME: NOTE: already disabled)
	*/

	local_irq_disable();
	local_fiq_disable();

	/*
	* Step 2: save registers
	*
	* The omap is a strange/beautiful device. The caches, memory
	* and register state are preserved across power saves.
	* We have to save and restore very little register state to
	* idle the omap.
	*
	* Save interrupt, MPUI, ARM and UPLD control registers.
	*/

	if (cpu_is_omap7xx()) {
	MPUI730_SAVE(OMAP_IH1_MIR);
	MPUI730_SAVE(OMAP_IH2_0_MIR);
	MPUI730_SAVE(OMAP_IH2_1_MIR);
	MPUI730_SAVE(MPUI_CTRL);
	MPUI730_SAVE(MPUI_DSP_BOOT_CONFIG);
	MPUI730_SAVE(MPUI_DSP_API_CONFIG);
	MPUI730_SAVE(EMIFS_CONFIG);
	MPUI730_SAVE(EMIFF_SDRAM_CONFIG);

	} else if (cpu_is_omap15xx()) {
	MPUI1510_SAVE(OMAP_IH1_MIR);
	MPUI1510_SAVE(OMAP_IH2_MIR);
	MPUI1510_SAVE(MPUI_CTRL);
	MPUI1510_SAVE(MPUI_DSP_BOOT_CONFIG);
	MPUI1510_SAVE(MPUI_DSP_API_CONFIG);
	MPUI1510_SAVE(EMIFS_CONFIG);
	MPUI1510_SAVE(EMIFF_SDRAM_CONFIG);
	} else if (cpu_is_omap16xx()) {
	MPUI1610_SAVE(OMAP_IH1_MIR);
	MPUI1610_SAVE(OMAP_IH2_0_MIR);
	MPUI1610_SAVE(OMAP_IH2_1_MIR);
	MPUI1610_SAVE(OMAP_IH2_2_MIR);
	MPUI1610_SAVE(OMAP_IH2_3_MIR);
	MPUI1610_SAVE(MPUI_CTRL);
	MPUI1610_SAVE(MPUI_DSP_BOOT_CONFIG);
	MPUI1610_SAVE(MPUI_DSP_API_CONFIG);
	MPUI1610_SAVE(EMIFS_CONFIG);
	MPUI1610_SAVE(EMIFF_SDRAM_CONFIG);
	}

	ARM_SAVE(ARM_CKCTL);
	ARM_SAVE(ARM_IDLECT1);
	ARM_SAVE(ARM_IDLECT2);
	if (!(cpu_is_omap15xx()))
	ARM_SAVE(ARM_IDLECT3);
	ARM_SAVE(ARM_EWUPCT);
	ARM_SAVE(ARM_RSTCT1);
	ARM_SAVE(ARM_RSTCT2);
	ARM_SAVE(ARM_SYSST);
	ULPD_SAVE(ULPD_CLOCK_CTRL);
	ULPD_SAVE(ULPD_STATUS_REQ);

	/* (Step 3 removed - we now allow deep sleep by default) */

	/*
	* Step 4: OMAP DSP Shutdown
	*/

	/* stop DSP */
	omap_writew(omap_readw(ARM_RSTCT1) & ~(1 << DSP_EN), ARM_RSTCT1);

	/* shut down dsp_ck */
	if (!cpu_is_omap7xx())
	omap_writew(omap_readw(ARM_CKCTL) & ~(1 << EN_DSPCK), ARM_CKCTL);

	/* temporarily enabling api_ck to access DSP registers */
	omap_writew(omap_readw(ARM_IDLECT2) \| 1 << EN_APICK, ARM_IDLECT2);

	/* save DSP registers */
	DSP_SAVE(DSP_IDLECT2);

	/* Stop all DSP domain clocks */
	__raw_writew(0, DSP_IDLECT2);

	/*
	* Step 5: Wakeup Event Setup
	*/

	omap_pm_wakeup_setup();

	/*
	* Step 6: ARM and Traffic controller shutdown
	*/

	/* disable ARM watchdog */
	omap_writel(0x00F5, OMAP_WDT_TIMER_MODE);
	omap_writel(0x00A0, OMAP_WDT_TIMER_MODE);

	/*
	* Step 6b: ARM and Traffic controller shutdown
	*
	* Step 6 continues here. Prepare jump to power management
	* assembly code in internal SRAM.
	*
	* Since the omap_cpu_suspend routine has been copied to
	* SRAM, we'll do an indirect procedure call to it and pass the
	* contents of arm_idlect1 and arm_idlect2 so it can restore
	* them when it wakes up and it will return.
	*/

	arg0 = arm_sleep_save[ARM_SLEEP_SAVE_ARM_IDLECT1];
	arg1 = arm_sleep_save[ARM_SLEEP_SAVE_ARM_IDLECT2];

	/*
	* Step 6c: ARM and Traffic controller shutdown
	*
	* Jump to assembly code. The processor will stay there
	* until wake up.
	*/
	omap_sram_suspend(arg0, arg1);

	/*
	* If we are here, processor is woken up!
	*/

	/*
	* Restore DSP clocks
	*/

	/* again temporarily enabling api_ck to access DSP registers */
	omap_writew(omap_readw(ARM_IDLECT2) \| 1 << EN_APICK, ARM_IDLECT2);

	/* Restore DSP domain clocks */
	DSP_RESTORE(DSP_IDLECT2);

	/*
	* Restore ARM state, except ARM_IDLECT1/2 which omap_cpu_suspend did
	*/

	if (!(cpu_is_omap15xx()))
	ARM_RESTORE(ARM_IDLECT3);
	ARM_RESTORE(ARM_CKCTL);
	ARM_RESTORE(ARM_EWUPCT);
	ARM_RESTORE(ARM_RSTCT1);
	ARM_RESTORE(ARM_RSTCT2);
	ARM_RESTORE(ARM_SYSST);
	ULPD_RESTORE(ULPD_CLOCK_CTRL);
	ULPD_RESTORE(ULPD_STATUS_REQ);

	if (cpu_is_omap7xx()) {
	MPUI730_RESTORE(EMIFS_CONFIG);
	MPUI730_RESTORE(EMIFF_SDRAM_CONFIG);
	MPUI730_RESTORE(OMAP_IH1_MIR);
	MPUI730_RESTORE(OMAP_IH2_0_MIR);
	MPUI730_RESTORE(OMAP_IH2_1_MIR);
	} else if (cpu_is_omap15xx()) {
	MPUI1510_RESTORE(MPUI_CTRL);
	MPUI1510_RESTORE(MPUI_DSP_BOOT_CONFIG);
	MPUI1510_RESTORE(MPUI_DSP_API_CONFIG);
	MPUI1510_RESTORE(EMIFS_CONFIG);
	MPUI1510_RESTORE(EMIFF_SDRAM_CONFIG);
	MPUI1510_RESTORE(OMAP_IH1_MIR);
	MPUI1510_RESTORE(OMAP_IH2_MIR);
	} else if (cpu_is_omap16xx()) {
	MPUI1610_RESTORE(MPUI_CTRL);
	MPUI1610_RESTORE(MPUI_DSP_BOOT_CONFIG);
	MPUI1610_RESTORE(MPUI_DSP_API_CONFIG);
	MPUI1610_RESTORE(EMIFS_CONFIG);
	MPUI1610_RESTORE(EMIFF_SDRAM_CONFIG);

	MPUI1610_RESTORE(OMAP_IH1_MIR);
	MPUI1610_RESTORE(OMAP_IH2_0_MIR);
	MPUI1610_RESTORE(OMAP_IH2_1_MIR);
	MPUI1610_RESTORE(OMAP_IH2_2_MIR);
	MPUI1610_RESTORE(OMAP_IH2_3_MIR);
	}

	if (!cpu_is_omap15xx())
	omap_writew(0, ULPD_SOFT_DISABLE_REQ_REG);

	/*
	* Re-enable interrupts
	*/

	local_irq_enable();
	local_fiq_enable();

	omap_serial_wake_trigger(0);

	printk(KERN_INFO "PM: OMAP%x is re-starting from deep sleep...\n",
	omap_rev());
	}

	#if defined(DEBUG) && defined(CONFIG_PROC_FS)
	static int g_read_completed;

	/*
	* Read system PM registers for debugging
	*/
	static int omap_pm_read_proc(
	char *page_buffer,
	char **my_first_byte,
	off_t virtual_start,
	int length,
	int *eof,
	void *data)
	{
	int my_buffer_offset = 0;
	char * const my_base = page_buffer;

	ARM_SAVE(ARM_CKCTL);
	ARM_SAVE(ARM_IDLECT1);
	ARM_SAVE(ARM_IDLECT2);
	if (!(cpu_is_omap15xx()))
	ARM_SAVE(ARM_IDLECT3);
	ARM_SAVE(ARM_EWUPCT);
	ARM_SAVE(ARM_RSTCT1);
	ARM_SAVE(ARM_RSTCT2);
	ARM_SAVE(ARM_SYSST);

	ULPD_SAVE(ULPD_IT_STATUS);
	ULPD_SAVE(ULPD_CLOCK_CTRL);
	ULPD_SAVE(ULPD_SOFT_REQ);
	ULPD_SAVE(ULPD_STATUS_REQ);
	ULPD_SAVE(ULPD_DPLL_CTRL);
	ULPD_SAVE(ULPD_POWER_CTRL);

	if (cpu_is_omap7xx()) {
	MPUI730_SAVE(MPUI_CTRL);
	MPUI730_SAVE(MPUI_DSP_STATUS);
	MPUI730_SAVE(MPUI_DSP_BOOT_CONFIG);
	MPUI730_SAVE(MPUI_DSP_API_CONFIG);
	MPUI730_SAVE(EMIFF_SDRAM_CONFIG);
	MPUI730_SAVE(EMIFS_CONFIG);
	} else if (cpu_is_omap15xx()) {
	MPUI1510_SAVE(MPUI_CTRL);
	MPUI1510_SAVE(MPUI_DSP_STATUS);
	MPUI1510_SAVE(MPUI_DSP_BOOT_CONFIG);
	MPUI1510_SAVE(MPUI_DSP_API_CONFIG);
	MPUI1510_SAVE(EMIFF_SDRAM_CONFIG);
	MPUI1510_SAVE(EMIFS_CONFIG);
	} else if (cpu_is_omap16xx()) {
	MPUI1610_SAVE(MPUI_CTRL);
	MPUI1610_SAVE(MPUI_DSP_STATUS);
	MPUI1610_SAVE(MPUI_DSP_BOOT_CONFIG);
	MPUI1610_SAVE(MPUI_DSP_API_CONFIG);
	MPUI1610_SAVE(EMIFF_SDRAM_CONFIG);
	MPUI1610_SAVE(EMIFS_CONFIG);
	}

	if (virtual_start == 0) {
	g_read_completed = 0;

	my_buffer_offset += sprintf(my_base + my_buffer_offset,
	"ARM_CKCTL_REG: 0x%-8x \n"
	"ARM_IDLECT1_REG: 0x%-8x \n"
	"ARM_IDLECT2_REG: 0x%-8x \n"
	"ARM_IDLECT3_REG: 0x%-8x \n"
	"ARM_EWUPCT_REG: 0x%-8x \n"
	"ARM_RSTCT1_REG: 0x%-8x \n"
	"ARM_RSTCT2_REG: 0x%-8x \n"
	"ARM_SYSST_REG: 0x%-8x \n"
	"ULPD_IT_STATUS_REG: 0x%-4x \n"
	"ULPD_CLOCK_CTRL_REG: 0x%-4x \n"
	"ULPD_SOFT_REQ_REG: 0x%-4x \n"
	"ULPD_DPLL_CTRL_REG: 0x%-4x \n"
	"ULPD_STATUS_REQ_REG: 0x%-4x \n"
	"ULPD_POWER_CTRL_REG: 0x%-4x \n",
	ARM_SHOW(ARM_CKCTL),
	ARM_SHOW(ARM_IDLECT1),
	ARM_SHOW(ARM_IDLECT2),
	ARM_SHOW(ARM_IDLECT3),
	ARM_SHOW(ARM_EWUPCT),
	ARM_SHOW(ARM_RSTCT1),
	ARM_SHOW(ARM_RSTCT2),
	ARM_SHOW(ARM_SYSST),
	ULPD_SHOW(ULPD_IT_STATUS),
	ULPD_SHOW(ULPD_CLOCK_CTRL),
	ULPD_SHOW(ULPD_SOFT_REQ),
	ULPD_SHOW(ULPD_DPLL_CTRL),
	ULPD_SHOW(ULPD_STATUS_REQ),
	ULPD_SHOW(ULPD_POWER_CTRL));

	if (cpu_is_omap7xx()) {
	my_buffer_offset += sprintf(my_base + my_buffer_offset,
	"MPUI730_CTRL_REG 0x%-8x \n"
	"MPUI730_DSP_STATUS_REG: 0x%-8x \n"
	"MPUI730_DSP_BOOT_CONFIG_REG: 0x%-8x \n"
	"MPUI730_DSP_API_CONFIG_REG: 0x%-8x \n"
	"MPUI730_SDRAM_CONFIG_REG: 0x%-8x \n"
	"MPUI730_EMIFS_CONFIG_REG: 0x%-8x \n",
	MPUI730_SHOW(MPUI_CTRL),
	MPUI730_SHOW(MPUI_DSP_STATUS),
	MPUI730_SHOW(MPUI_DSP_BOOT_CONFIG),
	MPUI730_SHOW(MPUI_DSP_API_CONFIG),
	MPUI730_SHOW(EMIFF_SDRAM_CONFIG),
	MPUI730_SHOW(EMIFS_CONFIG));
	} else if (cpu_is_omap15xx()) {
	my_buffer_offset += sprintf(my_base + my_buffer_offset,
	"MPUI1510_CTRL_REG 0x%-8x \n"
	"MPUI1510_DSP_STATUS_REG: 0x%-8x \n"
	"MPUI1510_DSP_BOOT_CONFIG_REG: 0x%-8x \n"
	"MPUI1510_DSP_API_CONFIG_REG: 0x%-8x \n"
	"MPUI1510_SDRAM_CONFIG_REG: 0x%-8x \n"
	"MPUI1510_EMIFS_CONFIG_REG: 0x%-8x \n",
	MPUI1510_SHOW(MPUI_CTRL),
	MPUI1510_SHOW(MPUI_DSP_STATUS),
	MPUI1510_SHOW(MPUI_DSP_BOOT_CONFIG),
	MPUI1510_SHOW(MPUI_DSP_API_CONFIG),
	MPUI1510_SHOW(EMIFF_SDRAM_CONFIG),
	MPUI1510_SHOW(EMIFS_CONFIG));
	} else if (cpu_is_omap16xx()) {
	my_buffer_offset += sprintf(my_base + my_buffer_offset,
	"MPUI1610_CTRL_REG 0x%-8x \n"
	"MPUI1610_DSP_STATUS_REG: 0x%-8x \n"
	"MPUI1610_DSP_BOOT_CONFIG_REG: 0x%-8x \n"
	"MPUI1610_DSP_API_CONFIG_REG: 0x%-8x \n"
	"MPUI1610_SDRAM_CONFIG_REG: 0x%-8x \n"
	"MPUI1610_EMIFS_CONFIG_REG: 0x%-8x \n",
	MPUI1610_SHOW(MPUI_CTRL),
	MPUI1610_SHOW(MPUI_DSP_STATUS),
	MPUI1610_SHOW(MPUI_DSP_BOOT_CONFIG),
	MPUI1610_SHOW(MPUI_DSP_API_CONFIG),
	MPUI1610_SHOW(EMIFF_SDRAM_CONFIG),
	MPUI1610_SHOW(EMIFS_CONFIG));
	}

	g_read_completed++;
	} else if (g_read_completed >= 1) {
	*eof = 1;
	return 0;
	}
	g_read_completed++;

	*my_first_byte = page_buffer;
	return my_buffer_offset;
	}

	static void omap_pm_init_proc(void)
	{
	struct proc_dir_entry *entry;

	entry = create_proc_read_entry("driver/omap_pm",
	S_IWUSR \| S_IRUGO, NULL,
	omap_pm_read_proc, NULL);
	}

	#endif /* DEBUG && CONFIG_PROC_FS */

	static void (*saved_idle)(void) = NULL;

	/*
	* omap_pm_prepare - Do preliminary suspend work.
	*
	*/
	static int omap_pm_prepare(void)
	{
	/* We cannot sleep in idle until we have resumed */
	saved_idle = pm_idle;
	pm_idle = NULL;

	return 0;
	}


	/*
	* omap_pm_enter - Actually enter a sleep state.
	* @state: State we're entering.
	*
	*/

	static int omap_pm_enter(suspend_state_t state)
	{
	switch (state)
	{
	case PM_SUSPEND_STANDBY:
	case PM_SUSPEND_MEM:
	omap1_pm_suspend();
	break;
	default:
	return -EINVAL;
	}

	return 0;
	}


	/**
	* omap_pm_finish - Finish up suspend sequence.
	*
	* This is called after we wake back up (or if entering the sleep state
	* failed).
	*/

	static void omap_pm_finish(void)
	{
	pm_idle = saved_idle;
	}


	static irqreturn_t omap_wakeup_interrupt(int irq, void *dev)
	{
	return IRQ_HANDLED;
	}

	static struct irqaction omap_wakeup_irq = {
	.name = "peripheral wakeup",
	.flags = IRQF_DISABLED,
	.handler = omap_wakeup_interrupt
	};



	static struct platform_suspend_ops omap_pm_ops ={
	.prepare = omap_pm_prepare,
	.enter = omap_pm_enter,
	.finish = omap_pm_finish,
	.valid = suspend_valid_only_mem,
	};

	static int __init omap_pm_init(void)
	{

	#ifdef CONFIG_OMAP_32K_TIMER
	int error;
	#endif

	printk("Power Management for TI OMAP.\n");

	/*
	* We copy the assembler sleep/wakeup routines to SRAM.
	* These routines need to be in SRAM as that's the only
	* memory the MPU can see when it wakes up.
	*/
	if (cpu_is_omap7xx()) {
	omap_sram_suspend = omap_sram_push(omap730_cpu_suspend,
	omap730_cpu_suspend_sz);
	} else if (cpu_is_omap15xx()) {
	omap_sram_suspend = omap_sram_push(omap1510_cpu_suspend,
	omap1510_cpu_suspend_sz);
	} else if (cpu_is_omap16xx()) {
	omap_sram_suspend = omap_sram_push(omap1610_cpu_suspend,
	omap1610_cpu_suspend_sz);
	}

	if (omap_sram_suspend == NULL) {
	printk(KERN_ERR "PM not initialized: Missing SRAM support\n");
	return -ENODEV;
	}

	pm_idle = omap1_pm_idle;

	if (cpu_is_omap7xx())
	setup_irq(INT_7XX_WAKE_UP_REQ, &omap_wakeup_irq);
	else if (cpu_is_omap16xx())
	setup_irq(INT_1610_WAKE_UP_REQ, &omap_wakeup_irq);

	/* Program new power ramp-up time
	* (0 for most boards since we don't lower voltage when in deep sleep)
	*/
	omap_writew(ULPD_SETUP_ANALOG_CELL_3_VAL, ULPD_SETUP_ANALOG_CELL_3);

	/* Setup ULPD POWER_CTRL_REG - enter deep sleep whenever possible */
	omap_writew(ULPD_POWER_CTRL_REG_VAL, ULPD_POWER_CTRL);

	/* Configure IDLECT3 */
	if (cpu_is_omap7xx())
	omap_writel(OMAP730_IDLECT3_VAL, OMAP730_IDLECT3);
	else if (cpu_is_omap16xx())
	omap_writel(OMAP1610_IDLECT3_VAL, OMAP1610_IDLECT3);

	suspend_set_ops(&omap_pm_ops);

	#if defined(DEBUG) && defined(CONFIG_PROC_FS)
	omap_pm_init_proc();
	#endif

	#ifdef CONFIG_OMAP_32K_TIMER
	error = sysfs_create_file(power_kobj, &sleep_while_idle_attr.attr);
	if (error)
	printk(KERN_ERR "sysfs_create_file failed: %d\n", error);
	#endif

	if (cpu_is_omap16xx()) {
	/* configure LOW_PWR pin */
	omap_cfg_reg(T20_1610_LOW_PWR);
	}

	return 0;
	}
	__initcall(omap_pm_init);