linux-sg2042/arch/arm/mach-pnx4008/pm.c

185 lines
4.1 KiB
C

/*
* arch/arm/mach-pnx4008/pm.c
*
* Power Management driver for PNX4008
*
* Authors: Vitaly Wool, Dmitry Chigirev <source@mvista.com>
*
* 2005 (c) MontaVista Software, Inc. This file is licensed under
* the terms of the GNU General Public License version 2. This program
* is licensed "as is" without any warranty of any kind, whether express
* or implied.
*/
#include <linux/pm.h>
#include <linux/rtc.h>
#include <linux/sched.h>
#include <linux/proc_fs.h>
#include <linux/pm.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <asm/io.h>
#include <asm/mach-types.h>
#include <asm/cacheflush.h>
#include <asm/arch/pm.h>
#include <asm/arch/clock.h>
#define SRAM_VA IO_ADDRESS(PNX4008_IRAM_BASE)
static void *saved_sram;
static struct clk *pll4_clk;
static inline void pnx4008_standby(void)
{
void (*pnx4008_cpu_standby_ptr) (void);
local_irq_disable();
local_fiq_disable();
clk_disable(pll4_clk);
/*saving portion of SRAM to be used by suspend function. */
memcpy(saved_sram, (void *)SRAM_VA, pnx4008_cpu_standby_sz);
/*make sure SRAM copy gets physically written into SDRAM.
SDRAM will be placed into self-refresh during power down */
flush_cache_all();
/*copy suspend function into SRAM */
memcpy((void *)SRAM_VA, pnx4008_cpu_standby, pnx4008_cpu_standby_sz);
/*do suspend */
pnx4008_cpu_standby_ptr = (void *)SRAM_VA;
pnx4008_cpu_standby_ptr();
/*restoring portion of SRAM that was used by suspend function */
memcpy((void *)SRAM_VA, saved_sram, pnx4008_cpu_standby_sz);
clk_enable(pll4_clk);
local_fiq_enable();
local_irq_enable();
}
static inline void pnx4008_suspend(void)
{
void (*pnx4008_cpu_suspend_ptr) (void);
local_irq_disable();
local_fiq_disable();
clk_disable(pll4_clk);
__raw_writel(0xffffffff, START_INT_RSR_REG(SE_PIN_BASE_INT));
__raw_writel(0xffffffff, START_INT_RSR_REG(SE_INT_BASE_INT));
/*saving portion of SRAM to be used by suspend function. */
memcpy(saved_sram, (void *)SRAM_VA, pnx4008_cpu_suspend_sz);
/*make sure SRAM copy gets physically written into SDRAM.
SDRAM will be placed into self-refresh during power down */
flush_cache_all();
/*copy suspend function into SRAM */
memcpy((void *)SRAM_VA, pnx4008_cpu_suspend, pnx4008_cpu_suspend_sz);
/*do suspend */
pnx4008_cpu_suspend_ptr = (void *)SRAM_VA;
pnx4008_cpu_suspend_ptr();
/*restoring portion of SRAM that was used by suspend function */
memcpy((void *)SRAM_VA, saved_sram, pnx4008_cpu_suspend_sz);
clk_enable(pll4_clk);
local_fiq_enable();
local_irq_enable();
}
static int pnx4008_pm_enter(suspend_state_t state)
{
switch (state) {
case PM_SUSPEND_STANDBY:
pnx4008_standby();
break;
case PM_SUSPEND_MEM:
pnx4008_suspend();
break;
case PM_SUSPEND_DISK:
return -ENOTSUPP;
default:
return -EINVAL;
}
return 0;
}
/*
* Called after processes are frozen, but before we shut down devices.
*/
static int pnx4008_pm_prepare(suspend_state_t state)
{
switch (state) {
case PM_SUSPEND_STANDBY:
case PM_SUSPEND_MEM:
break;
case PM_SUSPEND_DISK:
return -ENOTSUPP;
break;
default:
return -EINVAL;
break;
}
return 0;
}
/*
* Called after devices are re-setup, but before processes are thawed.
*/
static int pnx4008_pm_finish(suspend_state_t state)
{
return 0;
}
/*
* Set to PM_DISK_FIRMWARE so we can quickly veto suspend-to-disk.
*/
static struct pm_ops pnx4008_pm_ops = {
.prepare = pnx4008_pm_prepare,
.enter = pnx4008_pm_enter,
.finish = pnx4008_pm_finish,
};
static int __init pnx4008_pm_init(void)
{
u32 sram_size_to_allocate;
pll4_clk = clk_get(0, "ck_pll4");
if (IS_ERR(pll4_clk)) {
printk(KERN_ERR
"PM Suspend cannot acquire ARM(PLL4) clock control\n");
return PTR_ERR(pll4_clk);
}
if (pnx4008_cpu_standby_sz > pnx4008_cpu_suspend_sz)
sram_size_to_allocate = pnx4008_cpu_standby_sz;
else
sram_size_to_allocate = pnx4008_cpu_suspend_sz;
saved_sram = kmalloc(sram_size_to_allocate, GFP_ATOMIC);
if (!saved_sram) {
printk(KERN_ERR
"PM Suspend: cannot allocate memory to save portion of SRAM\n");
clk_put(pll4_clk);
return -ENOMEM;
}
pm_set_ops(&pnx4008_pm_ops);
return 0;
}
late_initcall(pnx4008_pm_init);