[ARM] 3605/1: AT91RM9200 Power Management (907d6deb) · Commits · 戴 / test

arch/arm/mach-at91rm9200/generic.h

+7 −0

Original line number	Diff line number	Diff line
		@@ -16,3 +16,10 @@ extern struct sys_timer at91rm9200_timer;
		extern void __init at91rm9200_map_io(void);

		extern int __init at91_clock_init(unsigned long main_clock);
		struct device;
		extern void __init at91_clock_associate(const char id, struct device dev, const char *func);

		/* Power Management */
		extern void at91_irq_suspend(void);
		extern void at91_irq_resume(void);

arch/arm/mach-at91rm9200/pm.c

0 → 100644

+225 −0

Original line number	Diff line number	Diff line
		/*
		* arch/arm/mach-at91rm9200/pm.c
		* AT91 Power Management
		*
		* Copyright (C) 2005 David Brownell
		*
		* 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.
		*/

		#include <linux/pm.h>
		#include <linux/sched.h>
		#include <linux/proc_fs.h>
		#include <linux/pm.h>
		#include <linux/interrupt.h>
		#include <linux/sysfs.h>
		#include <linux/module.h>
		#include <linux/platform_device.h>

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

		#include <asm/arch/gpio.h>

		#include "generic.h"


		static int at91_pm_valid_state(suspend_state_t state)
		{
		switch (state) {
		case PM_SUSPEND_ON:
		case PM_SUSPEND_STANDBY:
		case PM_SUSPEND_MEM:
		return 1;

		default:
		return 0;
		}
		}


		static suspend_state_t target_state;

		/*
		* Called after processes are frozen, but before we shutdown devices.
		*/
		static int at91_pm_prepare(suspend_state_t state)
		{
		target_state = state;
		return 0;
		}

		/*
		* Verify that all the clocks are correct before entering
		* slow-clock mode.
		*/
		static int at91_pm_verify_clocks(void)
		{
		unsigned long scsr;
		int i;

		scsr = at91_sys_read(AT91_PMC_SCSR);

		/* USB must not be using PLLB */
		if ((scsr & (AT91_PMC_UHP \| AT91_PMC_UDP)) != 0) {
		pr_debug("AT91: PM - Suspend-to-RAM with USB still active\n");
		return 0;
		}

		#ifdef CONFIG_AT91_PROGRAMMABLE_CLOCKS
		/* PCK0..PCK3 must be disabled, or configured to use clk32k */
		for (i = 0; i < 4; i++) {
		u32 css;

		if ((scsr & (AT91_PMC_PCK0 << i)) == 0)
		continue;

		css = at91_sys_read(AT91_PMC_PCKR(i)) & AT91_PMC_CSS;
		if (css != AT91_PMC_CSS_SLOW) {
		pr_debug("AT91: PM - Suspend-to-RAM with PCK%d src %d\n", i, css);
		return 0;
		}
		}
		#endif

		return 1;
		}

		/*
		* Call this from platform driver suspend() to see how deeply to suspend.
		* For example, some controllers (like OHCI) need one of the PLL clocks
		* in order to act as a wakeup source, and those are not available when
		* going into slow clock mode.
		*
		* REVISIT: generalize as clk_will_be_available(clk)? Other platforms have
		* the very same problem (but not using at91 main_clk), and it'd be better
		* to add one generic API rather than lots of platform-specific ones.
		*/
		int at91_suspend_entering_slow_clock(void)
		{
		return (target_state == PM_SUSPEND_MEM);
		}
		EXPORT_SYMBOL(at91_suspend_entering_slow_clock);


		static void (*slow_clock)(void);



		static int at91_pm_enter(suspend_state_t state)
		{
		at91_gpio_suspend();
		at91_irq_suspend();

		pr_debug("AT91: PM - wake mask %08x, pm state %d\n",
		/* remember all the always-wake irqs */
		(at91_sys_read(AT91_PMC_PCSR)
		\| (1 << AT91_ID_FIQ)
		\| (1 << AT91_ID_SYS)
		\| (1 << AT91_ID_IRQ0)
		\| (1 << AT91_ID_IRQ1)
		\| (1 << AT91_ID_IRQ2)
		\| (1 << AT91_ID_IRQ3)
		\| (1 << AT91_ID_IRQ4)
		\| (1 << AT91_ID_IRQ5)
		\| (1 << AT91_ID_IRQ6))
		& at91_sys_read(AT91_AIC_IMR),
		state);

		switch (state) {
		/*
		* Suspend-to-RAM is like STANDBY plus slow clock mode, so
		* drivers must suspend more deeply: only the master clock
		* controller may be using the main oscillator.
		*/
		case PM_SUSPEND_MEM:
		/*
		* Ensure that clocks are in a valid state.
		*/
		if (!at91_pm_verify_clocks())
		goto error;

		/*
		* Enter slow clock mode by switching over to clk32k and
		* turning off the main oscillator; reverse on wakeup.
		*/
		if (slow_clock) {
		slow_clock();
		break;
		} else {
		/* DEVELOPMENT ONLY */
		pr_info("AT91: PM - no slow clock mode yet ...\n");
		/* FALLTHROUGH leaving master clock alone */
		}

		/*
		* STANDBY mode has all drivers suspended; ignores irqs not
		* marked as 'wakeup' event sources; and reduces DRAM power.
		* But otherwise it's identical to PM_SUSPEND_ON: cpu idle, and
		* nothing fancy done with main or cpu clocks.
		*/
		case PM_SUSPEND_STANDBY:
		/*
		* NOTE: the Wait-for-Interrupt instruction needs to be
		* in icache so the SDRAM stays in self-refresh mode until
		* the wakeup IRQ occurs.
		*/
		asm("b 1f; .align 5; 1:");
		asm("mcr p15, 0, r0, c7, c10, 4"); /* drain write buffer */
		at91_sys_write(AT91_SDRAMC_SRR, 1); /* self-refresh mode */
		/* fall though to next state */

		case PM_SUSPEND_ON:
		asm("mcr p15, 0, r0, c7, c0, 4"); /* wait for interrupt */
		break;

		default:
		pr_debug("AT91: PM - bogus suspend state %d\n", state);
		goto error;
		}

		pr_debug("AT91: PM - wakeup %08x\n",
		at91_sys_read(AT91_AIC_IPR) & at91_sys_read(AT91_AIC_IMR));

		error:
		target_state = PM_SUSPEND_ON;
		at91_irq_resume();
		at91_gpio_resume();
		return 0;
		}


		static struct pm_ops at91_pm_ops ={
		.pm_disk_mode = 0,
		.valid = at91_pm_valid_state,
		.prepare = at91_pm_prepare,
		.enter = at91_pm_enter,
		};

		static int __init at91_pm_init(void)
		{
		printk("AT91: Power Management\n");

		#ifdef CONFIG_AT91_PM_SLOW_CLOCK
		/* REVISIT allocations of SRAM should be dynamically managed.
		* FIQ handlers and other components will want SRAM/TCM too...
		*/
		slow_clock = (void ) (AT91_VA_BASE_SRAM + (3 SZ_4K));
		memcpy(slow_clock, at91rm9200_slow_clock, at91rm9200_slow_clock_sz);
		#endif

		/* Disable SDRAM low-power mode. Cannot be used with self-refresh. */
		at91_sys_write(AT91_SDRAMC_LPR, 0);

		pm_set_ops(&at91_pm_ops);

		return 0;
		}
		arch_initcall(at91_pm_init);

include/asm-arm/arch-at91rm9200/gpio.h

+5 −0

Original line number	Diff line number	Diff line
		@@ -13,6 +13,8 @@
		#ifndef __ASM_ARCH_AT91RM9200_GPIO_H
		#define __ASM_ARCH_AT91RM9200_GPIO_H

		#include <asm/irq.h>

		#define PIN_BASE NR_AIC_IRQS

		#define PQFP_GPIO_BANKS 3 /* PQFP package has 3 banks */
		@@ -188,6 +190,9 @@ extern int at91_set_multi_drive(unsigned pin, int is_on);
		/* callable at any time */
		extern int at91_set_gpio_value(unsigned pin, int value);
		extern int at91_get_gpio_value(unsigned pin);

		extern void at91_gpio_suspend(void);
		extern void at91_gpio_resume(void);
		#endif

		#endif

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