pm.c

h内核

/* linux/arch/arm/mach-s3c2410/pm.c
 *
 * Copyright (c) 2004 Simtec Electronics
 *	Ben Dooks <[e-mail]>
 *
 * S3C2410 Power Manager (Suspend-To-RAM) support
 *
 * See Documentation/arm/Samsung-S3C24XX/Suspend.txt for more information
 *
 * 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 program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Parts based on arch/arm/mach-pxa/pm.c
 *
 * Thanks to Dimitry Andric for debugging
*/

#include <linux/config.h>
#include <linux/init.h>
#include <linux/suspend.h>
#include <linux/errno.h>
#include <linux/time.h>
#include <linux/interrupt.h>
#include <linux/crc32.h>
#include <linux/ioport.h>
#include <linux/delay.h>

#include <asm/hardware.h>
#include <asm/io.h>

#include <asm/arch/regs-serial.h>
#include <asm/arch/regs-clock.h>
#include <asm/arch/regs-gpio.h>
#include <asm/arch/regs-mem.h>
#include <asm/arch/regs-irq.h>

#include <asm/mach/time.h>

#include "pm.h"

/* for external use */

unsigned long s3c_pm_flags;

/* cache functions from arch/arm/mm/proc-arm920.S */

extern void arm920_flush_kern_cache_all(void);

#define PFX "s3c24xx-pm: "

static struct sleep_save core_save[] = {
	SAVE_ITEM(S3C2410_LOCKTIME),
	SAVE_ITEM(S3C2410_CLKCON),

	/* we restore the timings here, with the proviso that the board
	 * brings the system up in an slower, or equal frequency setting
	 * to the original system.
	 *
	 * if we cannot guarantee this, then things are going to go very
	 * wrong here, as we modify the refresh and both pll settings.
	 */

	SAVE_ITEM(S3C2410_BWSCON),
	SAVE_ITEM(S3C2410_BANKCON0),
	SAVE_ITEM(S3C2410_BANKCON1),
	SAVE_ITEM(S3C2410_BANKCON2),
	SAVE_ITEM(S3C2410_BANKCON3),
	SAVE_ITEM(S3C2410_BANKCON4),
	SAVE_ITEM(S3C2410_BANKCON5),

	SAVE_ITEM(S3C2410_CLKDIVN),
	SAVE_ITEM(S3C2410_MPLLCON),
	SAVE_ITEM(S3C2410_UPLLCON),
	SAVE_ITEM(S3C2410_CLKSLOW),
	SAVE_ITEM(S3C2410_REFRESH),
};

/* this lot should be really saved by the IRQ code */
static struct sleep_save irq_save[] = {
	SAVE_ITEM(S3C2410_EXTINT0),
	SAVE_ITEM(S3C2410_EXTINT1),
	SAVE_ITEM(S3C2410_EXTINT2),
	SAVE_ITEM(S3C2410_EINFLT0),
	SAVE_ITEM(S3C2410_EINFLT1),
	SAVE_ITEM(S3C2410_EINFLT2),
	SAVE_ITEM(S3C2410_EINFLT3),
	SAVE_ITEM(S3C2410_EINTMASK),
	SAVE_ITEM(S3C2410_INTMSK)
};

static struct sleep_save gpio_save[] = {
	SAVE_ITEM(S3C2410_GPACON),
	SAVE_ITEM(S3C2410_GPADAT),

	SAVE_ITEM(S3C2410_GPBCON),
	SAVE_ITEM(S3C2410_GPBDAT),
	SAVE_ITEM(S3C2410_GPBUP),

	SAVE_ITEM(S3C2410_GPCCON),
	SAVE_ITEM(S3C2410_GPCDAT),
	SAVE_ITEM(S3C2410_GPCUP),

	SAVE_ITEM(S3C2410_GPDCON),
	SAVE_ITEM(S3C2410_GPDDAT),
	SAVE_ITEM(S3C2410_GPDUP),

	SAVE_ITEM(S3C2410_GPECON),
	SAVE_ITEM(S3C2410_GPEDAT),
	SAVE_ITEM(S3C2410_GPEUP),

	SAVE_ITEM(S3C2410_GPFCON),
	SAVE_ITEM(S3C2410_GPFDAT),
	SAVE_ITEM(S3C2410_GPFUP),

	SAVE_ITEM(S3C2410_GPGCON),
	SAVE_ITEM(S3C2410_GPGDAT),
	SAVE_ITEM(S3C2410_GPGUP),

	SAVE_ITEM(S3C2410_GPHCON),
	SAVE_ITEM(S3C2410_GPHDAT),
	SAVE_ITEM(S3C2410_GPHUP),

	SAVE_ITEM(S3C2410_DCLKCON),
};

#ifdef CONFIG_S3C2410_PM_DEBUG

#define SAVE_UART(va) \
	SAVE_ITEM((va) + S3C2410_ULCON), \
	SAVE_ITEM((va) + S3C2410_UCON), \
	SAVE_ITEM((va) + S3C2410_UFCON), \
	SAVE_ITEM((va) + S3C2410_UMCON), \
	SAVE_ITEM((va) + S3C2410_UBRDIV)

static struct sleep_save uart_save[] = {
	SAVE_UART(S3C2410_VA_UART0),
	SAVE_UART(S3C2410_VA_UART1),
	SAVE_UART(S3C2410_VA_UART2),
};

/* debug
 *
 * we send the debug to printascii() to allow it to be seen if the
 * system never wakes up from the sleep
*/

extern void printascii(const char *);

static void pm_dbg(const char *fmt, ...)
{
	va_list va;
	char buff[256];

	va_start(va, fmt);
	vsprintf(buff, fmt, va);
	va_end(va);

	printascii(buff);
}

static void s3c2410_pm_debug_init(void)
{
	unsigned long tmp = __raw_readl(S3C2410_CLKCON);

	/* re-start uart clocks */
	tmp |= S3C2410_CLKCON_UART0;
	tmp |= S3C2410_CLKCON_UART1;
	tmp |= S3C2410_CLKCON_UART2;

	__raw_writel(tmp, S3C2410_CLKCON);
	udelay(10);
}

#define DBG(fmt...) pm_dbg(fmt)
#else
#define DBG(fmt...) printk(KERN_DEBUG fmt)

#define s3c2410_pm_debug_init() do { } while(0)

static struct sleep_save uart_save[] = {};
#endif

#if defined(CONFIG_S3C2410_PM_CHECK) && CONFIG_S3C2410_PM_CHECK_CHUNKSIZE != 0

/* suspend checking code...
 *
 * this next area does a set of crc checks over all the installed
 * memory, so the system can verify if the resume was ok.
 *
 * CONFIG_S3C2410_PM_CHECK_CHUNKSIZE defines the block-size for the CRC,
 * increasing it will mean that the area corrupted will be less easy to spot,
 * and reducing the size will cause the CRC save area to grow
*/

#define CHECK_CHUNKSIZE (CONFIG_S3C2410_PM_CHECK_CHUNKSIZE * 1024)

static u32 crc_size;	/* size needed for the crc block */
static u32 *crcs;	/* allocated over suspend/resume */

typedef u32 *(run_fn_t)(struct resource *ptr, u32 *arg);

/* s3c2410_pm_run_res
 *
 * go thorugh the given resource list, and look for system ram
*/

static void s3c2410_pm_run_res(struct resource *ptr, run_fn_t fn, u32 *arg)
{
	while (ptr != NULL) {
		if (ptr->child != NULL)
			s3c2410_pm_run_res(ptr->child, fn, arg);

		if ((ptr->flags & IORESOURCE_MEM) &&
		    strcmp(ptr->name, "System RAM") == 0) {
			DBG("Found system RAM at %08lx..%08lx\n",
			    ptr->start, ptr->end);
			arg = (fn)(ptr, arg);
		}

		ptr = ptr->sibling;
	}
}

static void s3c2410_pm_run_sysram(run_fn_t fn, u32 *arg)
{
	s3c2410_pm_run_res(&iomem_resource, fn, arg);
}

static u32 *s3c2410_pm_countram(struct resource *res, u32 *val)
{
	u32 size = (u32)(res->end - res->start)+1;

	size += CHECK_CHUNKSIZE-1;
	size /= CHECK_CHUNKSIZE;

	DBG("Area %08lx..%08lx, %d blocks\n", res->start, res->end, size);

	*val += size * sizeof(u32);
	return val;
}

/* s3c2410_pm_prepare_check
 *
 * prepare the necessary information for creating the CRCs. This
 * must be done before the final save, as it will require memory
 * allocating, and thus touching bits of the kernel we do not
 * know about.
*/

static void s3c2410_pm_check_prepare(void)
{
	crc_size = 0;

	s3c2410_pm_run_sysram(s3c2410_pm_countram, &crc_size);

	DBG("s3c2410_pm_prepare_check: %u checks needed\n", crc_size);

	crcs = kmalloc(crc_size+4, GFP_KERNEL);
	if (crcs == NULL)
		printk(KERN_ERR "Cannot allocated CRC save area\n");
}

static u32 *s3c2410_pm_makecheck(struct resource *res, u32 *val)
{
	unsigned long addr, left;

	for (addr = res->start; addr < res->end;
	     addr += CHECK_CHUNKSIZE) {
		left = res->end - addr;

		if (left > CHECK_CHUNKSIZE)
			left = CHECK_CHUNKSIZE;

		*val = crc32_le(~0, phys_to_virt(addr), left);
		val++;
	}

	return val;
}

/* s3c2410_pm_check_store
 *
 * compute the CRC values for the memory blocks before the final
 * sleep.
*/

static void s3c2410_pm_check_store(void)
{
	if (crcs != NULL)
		s3c2410_pm_run_sysram(s3c2410_pm_makecheck, crcs);
}

/* in_region
 *
 * return TRUE if the area defined by ptr..ptr+size contatins the
 * what..what+whatsz
*/

static inline int in_region(void *ptr, int size, void *what, size_t whatsz)
{
	if ((what+whatsz) < ptr)
		return 0;

	if (what > (ptr+size))
		return 0;

	return 1;
}

static u32 *s3c2410_pm_runcheck(struct resource *res, u32 *val)
{
	void *save_at = phys_to_virt(s3c2410_sleep_save_phys);
	unsigned long addr;
	unsigned long left;
	void *ptr;
	u32 calc;

	for (addr = res->start; addr < res->end;
	     addr += CHECK_CHUNKSIZE) {
		left = res->end - addr;

		if (left > CHECK_CHUNKSIZE)
			left = CHECK_CHUNKSIZE;