| pm-arch3.patch | | arch/arm/mach-s3c2410 power management support | | Files affected: | arch/arm/mach-s3c2410/Kconfig | 27 27 + 0 - 0 ! | arch/arm/mach-s3c2410/Makefile | 4 4 + 0 - 0 ! | arch/arm/mach-s3c2410/pm.c | 583 583 + 0 - 0 ! | arch/arm/mach-s3c2410/pm.h | 36 36 + 0 - 0 ! | arch/arm/mach-s3c2410/sleep.S | 168 168 + 0 - 0 ! | 5 files changed, 818 insertions(+) | | Ben Dooks, Thu, 07 Oct 2004 15:13:30 +0100 diff -urN -X ../dontdiff linux-2.6.9-rc3-bk5-rmktimer/arch/arm/mach-s3c2410/Kconfig linux-2.6.9-rc3-bk5-rmktimer-pm1/arch/arm/mach-s3c2410/Kconfig --- linux-2.6.9-rc3-bk5-rmktimer/arch/arm/mach-s3c2410/Kconfig 2004-10-04 22:57:06.000000000 +0100 +++ linux-2.6.9-rc3-bk5-rmktimer-pm1/arch/arm/mach-s3c2410/Kconfig 2004-10-07 12:32:10.000000000 +0100 @@ -72,4 +72,31 @@ the CPU time doing so. +config S3C2410_PM_DEBUG + bool "S3C2410 PM Suspend debug" + depends on ARCH_S3C2410 && PM + help + Say Y here if you want verbose debugging from the PM Suspend and + Resume code. See `Documentation/arm/Samsing-S3C24XX/Suspend.txt` + for more information. + +config S3C2410_PM_CHECK + bool "S3C2410 PM Suspend Memory CRC" + depends on ARCH_S3C2410 && PM && CRC32 + help + Enable the PM code's memory area checksum over sleep. This option + will generate CRCs of all blocks of memory, and store them before + going to sleep. The blocks are then checked on resume for any + errors. + +config S3C2410_PM_CHECK_CHUNKSIZE + int "S3C2410 PM Suspend CRC Chunksize (KiB)" + depends on ARCH_S3C2410 && PM && S3C2410_PM_CHECK + default 64 + help + Set the chunksize in Kilobytes of the CRC for checking memory + corruption over suspend and resume. A smaller value will mean that + the CRC data block will take more memory, but wil identify any + faults with better precision. + endif diff -urN -X ../dontdiff linux-2.6.9-rc3-bk5-rmktimer/arch/arm/mach-s3c2410/Makefile linux-2.6.9-rc3-bk5-rmktimer-pm1/arch/arm/mach-s3c2410/Makefile --- linux-2.6.9-rc3-bk5-rmktimer/arch/arm/mach-s3c2410/Makefile 2004-10-05 15:02:52.000000000 +0100 +++ linux-2.6.9-rc3-bk5-rmktimer-pm1/arch/arm/mach-s3c2410/Makefile 2004-10-05 22:19:23.000000000 +0100 @@ -15,6 +15,10 @@ obj-$(CONFIG_CPU_S3C2410) += s3c2410.o obj-$(CONFIG_S3C2410_DMA) += dma.o +# Power Management support + +obj-$(CONFIG_PM) += pm.o sleep.o + # S3C2440 support obj-$(CONFIG_CPU_S3C2440) += s3c2440.o s3c2440-dsc.o diff -urN -X ../dontdiff linux-2.6.9-rc3-bk5-rmktimer/arch/arm/mach-s3c2410/pm.c linux-2.6.9-rc3-bk5-rmktimer-pm1/arch/arm/mach-s3c2410/pm.c --- linux-2.6.9-rc3-bk5-rmktimer/arch/arm/mach-s3c2410/pm.c 1970-01-01 01:00:00.000000000 +0100 +++ linux-2.6.9-rc3-bk5-rmktimer-pm1/arch/arm/mach-s3c2410/pm.c 2004-10-07 13:38:36.000000000 +0100 @@ -0,0 +1,583 @@ +/* linux/arch/arm/mach-s3c2410/pm.c + * + * Copyright (c) 2004 Simtec Electronics + * Ben Dooks + * + * 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 + * +*/ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include +#include +#include +#include + +#include + +#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: " + +/* sleep save info */ + +struct sleep_save { + unsigned long reg; + unsigned long val; +}; + +#define SAVE_ITEM(x) \ + { .reg = (x) } + +static struct sleep_save core_save[] = { + SAVE_ITEM(S3C2410_LOCKTIME), + SAVE_ITEM(S3C2410_CLKCON) +}; + +/* this lot should be really saved by the IRQ code */ +static struct sleep_save irq_save[] = { + SAVE_ITEM(S3C2410_EINTMASK), + SAVE_ITEM(S3C2410_INTMSK), + SAVE_ITEM(S3C2410_EINFLT0), + SAVE_ITEM(S3C2410_EINFLT1), + SAVE_ITEM(S3C2410_EINFLT2), + SAVE_ITEM(S3C2410_EINFLT3) +}; + +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), +}; + +#ifdef CONFIG_S3C2410_PM_DEBUG +/* debug + * + */ + +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); +} + + +#define DBG(fmt...) pm_dbg(fmt) +#else +#define DBG(fmt...) printk(KERN_DEBUG fmt) +#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; + + ptr = phys_to_virt(addr); + + if (in_region(ptr, left, crcs, crc_size)) { + DBG("skipping %08lx, has crc block in\n", addr); + goto skip_check; + } + + if (in_region(ptr, left, save_at, 32*4 )) { + DBG("skipping %08lx, has save block in\n", addr); + goto skip_check; + } + + /* calculate and check the checksum */ + + calc = crc32_le(~0, ptr, left); + if (calc != *val) { + printk(KERN_ERR PFX "Restore CRC error at " + "%08lx (%08x vs %08x)\n", addr, calc, *val); + + DBG("Restore CRC error at %08lx (%08x vs %08x)\n", + addr, calc, *val); + } + + skip_check: + val++; + } + + return val; +} + +/* s3c2410_pm_check_restore + * + * check the CRCs after the restore event and free the memory used + * to hold them +*/ + +static void s3c2410_pm_check_restore(void) +{ + if (crcs != NULL) { + s3c2410_pm_run_sysram(s3c2410_pm_runcheck, crcs); + kfree(crcs); + crcs = NULL; + } +} + +#else +#define s3c2410_pm_check_prepare() do { } while(0) +#define s3c2410_pm_check_restore() do { } while(0) +#define s3c2410_pm_check_store() do { } while(0) +#endif + +/* helper functions to save and restore register state */ + +static void s3c2410_pm_do_save(struct sleep_save *ptr, int count) +{ + for (; count > 0; count--, ptr++) { + ptr->val = __raw_readl(ptr->reg); + DBG("saved %08x value %08x\n", ptr->reg, ptr->val); + } +} + + +static void s3c2410_pm_do_restore(struct sleep_save *ptr, int count) +{ + for (; count > 0; count--, ptr++) { + DBG("restore %08x (restore %08x, current %08x)\n", + ptr->reg, ptr->val, __raw_readl(ptr->reg)); + __raw_writel(ptr->val, ptr->reg); + } +} + +/* s3c2410_pm_show_resume_irqs + * + * print any IRQs asserted at resume time (ie, we woke from) +*/ + +static void s3c2410_pm_show_resume_irqs(int start, unsigned long which, + unsigned long mask) +{ + int i; + + which &= ~mask; + + for (i = 0; i <= 31; i++) { + if ((which) & (1L<>= S3C2410_GPIO_OFFSET(pin)*2; + + if (!irqstate) { + if (pinstate == 0x02) + DBG("Leaving IRQ %d (pin %d) enabled\n", irq, pin); + } else { + if (pinstate == 0x02) { + DBG("Disabling IRQ %d (pin %d)\n", irq, pin); + s3c2410_gpio_cfgpin(pin, 0x00); + } + } +} + +/* s3c2410_pm_configure_extint + * + * configure all external interrupt pins +*/ + +static void s3c2410_pm_configure_extint(void) +{ + int pin; + + /* for each of the external interrupts (EINT0..EINT15) we + * need to check wether it is an external interrupt source, + * and then configure it as an input if it is not + */ + + for (pin = S3C2410_GPF0; pin <= S3C2410_GPF7; pin++) { + s3c2410_pm_check_resume_pin(pin, pin - S3C2410_GPF0); + } + + for (pin = S3C2410_GPG0; pin <= S3C2410_GPG7; pin++) { + s3c2410_pm_check_resume_pin(pin, (pin - S3C2410_GPG0)+8); + } +} + +#define any_allowed(mask, allow) (((mask) & (allow)) != (allow)) + +/* s3c2410_pm_enter + * + * central control for sleep/resume process +*/ + +static int s3c2410_pm_enter(u32 state) +{ + unsigned long regs_save[16]; + unsigned long tmp; + + DBG("s3c2410_pm_enter(%d)\n", state); + + if (state != PM_SUSPEND_MEM) { + printk(KERN_ERR PFX "error: only PM_SUSPEND_MEM supported\n"); + return -EINVAL; + } + + /* check if we have anything to wake-up with... bad things seem + * to happen if you suspend with no wakeup (system will often + * require a full power-cycle) + */ + + if (!any_allowed(s3c_irqwake_intmask, s3c_irqwake_intallow) && + !any_allowed(s3c_irqwake_eintmask, s3c_irqwake_eintallow)) { + printk(KERN_ERR PFX "No sources enabled for wake-up!\n"); + printk(KERN_ERR PFX "Aborting sleep\n"); + return -EINVAL; + } + + /* prepare check area if configured */ + + s3c2410_pm_check_prepare(); + + /* store the physical address of the register recovery block */ + + s3c2410_sleep_save_phys = virt_to_phys(regs_save); + + DBG("s3c2410_sleep_save_phys=0x%08x\n", s3c2410_sleep_save_phys); + + /* ensure at least GESTATUS3 has the resume address */ + + __raw_writel(virt_to_phys(s3c2410_cpu_resume), S3C2410_GSTATUS3); + + DBG("GSTATUS3 0x%08lx\n", __raw_readl(S3C2410_GSTATUS3)); + DBG("GSTATUS4 0x%08lx\n", __raw_readl(S3C2410_GSTATUS4)); + + /* save all necessary core registers not covered by the drivers */ + + s3c2410_pm_do_save(gpio_save, ARRAY_SIZE(gpio_save)); + s3c2410_pm_do_save(irq_save, ARRAY_SIZE(irq_save)); + s3c2410_pm_do_save(core_save, ARRAY_SIZE(core_save)); + + /* set the irq configuration for wake */ + + s3c2410_pm_configure_extint(); + + DBG("sleep: irq wakeup masks: %08lx,%08lx\n", + s3c_irqwake_intmask, s3c_irqwake_eintmask); + + __raw_writel(s3c_irqwake_intmask, S3C2410_INTMSK); + __raw_writel(s3c_irqwake_eintmask, S3C2410_EINTMASK); + + /* ack any outstanding external interrupts before we go to sleep */ + + __raw_writel(S3C2410_EINTPEND, __raw_readl(S3C2410_EINTPEND)); + + /* flush cache back to ram */ + + arm920_flush_kern_cache_all(); + + s3c2410_pm_check_store(); + + // need to make some form of time-delta + + /* send the cpu to sleep... */ + + __raw_writel(0x00, S3C2410_CLKCON); /* turn off clocks over sleep */ + + s3c2410_cpu_suspend(regs_save); + + /* unset the return-from-sleep flag, to ensure reset */ + + tmp = __raw_readl(S3C2410_GSTATUS2); + tmp &= S3C2410_GSTATUs2_OFFRESET; + __raw_writel(tmp, S3C2410_GSTATUS2); + + /* check what irq (if any) restored the system */ + + DBG("post sleep: IRQs 0x%08lx, 0x%08lx\n", + __raw_readl(S3C2410_SRCPND), + __raw_readl(S3C2410_EINTPEND)); + + s3c2410_pm_show_resume_irqs(IRQ_EINT0, __raw_readl(S3C2410_SRCPND), + s3c_irqwake_intmask); + + s3c2410_pm_show_resume_irqs(IRQ_EINT4-4, __raw_readl(S3C2410_EINTPEND), + s3c_irqwake_eintmask); + + DBG("post sleep, restoring state...\n"); + + s3c2410_pm_do_restore(core_save, ARRAY_SIZE(core_save)); + s3c2410_pm_do_restore(gpio_save, ARRAY_SIZE(gpio_save)); + s3c2410_pm_do_restore(irq_save, ARRAY_SIZE(irq_save)); + + DBG("post sleep, preparing to return\n"); + + s3c2410_pm_check_restore(); + + /* ok, let's return from sleep */ + + DBG("S3C2410 PM Resume (post-restore)\n"); + return 0; +} + +/* + * Called after processes are frozen, but before we shut down devices. + */ +static int s3c2410_pm_prepare(u32 state) +{ + return 0; +} + +/* + * Called after devices are re-setup, but before processes are thawed. + */ +static int s3c2410_pm_finish(u32 state) +{ + return 0; +} + +/* + * Set to PM_DISK_FIRMWARE so we can quickly veto suspend-to-disk. + */ +static struct pm_ops s3c2410_pm_ops = { + .pm_disk_mode = PM_DISK_FIRMWARE, + .prepare = s3c2410_pm_prepare, + .enter = s3c2410_pm_enter, + .finish = s3c2410_pm_finish, +}; + +/* s3c2410_pm_init + * + * Attach the power management functions. This should be called + * from the board specific initialisation if the board supports + * it. +*/ + +int __init s3c2410_pm_init(void) +{ + printk("S3C2410 Power Management, (c) 2004 Simtec Electronics\n"); + + pm_set_ops(&s3c2410_pm_ops); + return 0; +} diff -urN -X ../dontdiff linux-2.6.9-rc3-bk5-rmktimer/arch/arm/mach-s3c2410/pm.h linux-2.6.9-rc3-bk5-rmktimer-pm1/arch/arm/mach-s3c2410/pm.h --- linux-2.6.9-rc3-bk5-rmktimer/arch/arm/mach-s3c2410/pm.h 1970-01-01 01:00:00.000000000 +0100 +++ linux-2.6.9-rc3-bk5-rmktimer-pm1/arch/arm/mach-s3c2410/pm.h 2004-10-07 13:35:00.000000000 +0100 @@ -0,0 +1,36 @@ +/* linux/arch/arm/mach-s3c2410/pm.h + * + * Copyright (c) 2004 Simtec Electronics + * Written by Ben Dooks, + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. +*/ + +/* s3c2410_pm_init + * + * called from board at initialisation time to setup the power + * management +*/ + +extern __init int s3c2410_pm_init(void); + +/* configuration for the IRQ mask over sleep */ +extern unsigned long s3c_irqwake_intmask; +extern unsigned long s3c_irqwake_eintmask; + +/* IRQ masks for IRQs allowed to go to sleep (see irq.c) */ +extern unsigned long s3c_irqwake_intallow; +extern unsigned long s3c_irqwake_eintallow; + +/* Flags for PM Control */ + +extern unsigned long s3c_pm_flags; + +/* from sleep.S */ + +extern void s3c2410_cpu_suspend(unsigned long *saveblk); +extern void s3c2410_cpu_resume(void); + +extern unsigned long s3c2410_sleep_save_phys; diff -urN -X ../dontdiff linux-2.6.9-rc3-bk5-rmktimer/arch/arm/mach-s3c2410/sleep.S linux-2.6.9-rc3-bk5-rmktimer-pm1/arch/arm/mach-s3c2410/sleep.S --- linux-2.6.9-rc3-bk5-rmktimer/arch/arm/mach-s3c2410/sleep.S 1970-01-01 01:00:00.000000000 +0100 +++ linux-2.6.9-rc3-bk5-rmktimer-pm1/arch/arm/mach-s3c2410/sleep.S 2004-10-05 23:51:39.000000000 +0100 @@ -0,0 +1,168 @@ +/* linux/arch/arm/mach-s3c2410/sleep.S + * + * Copyright (c) 2004 Simtec Electronics + * Ben Dooks + * + * S3C2410 Power Manager (Suspend-To-RAM) support + * + * Based on PXA/SA1100 sleep code by: + * Nicolas Pitre, (c) 2002 Monta Vista Software Inc + * Cliff Brake, (c) 2001 + * + * 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 +*/ + +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +#define CONFIG_DEBUG_RESUME + + .text + + /* s3c2410_cpu_suspend + * + * put the cpu into sleep mode + * + * entry: + * r0 = sleep save block + */ + +ENTRY(s3c2410_cpu_suspend) + stmfd sp!, { r4 - r12, lr } + + @@ store co-processor registers + + mrc p15, 0, r4, c15, c1, 0 @ CP access register + mrc p15, 0, r5, c13, c0, 0 @ PID + mrc p15, 0, r6, c3, c0, 0 @ Domain ID + mrc p15, 0, r7, c2, c0, 0 @ translation table base address + mrc p15, 0, r8, c2, c0, 0 @ auxiliary control register + mrc p15, 0, r9, c1, c0, 0 @ control register + + stmia r0, { r4 - r13 } + + @@ flush the caches to ensure everything is back out to + @@ SDRAM before the core powers down + + bl arm920_flush_kern_cache_all + + @@ prepare cpu to sleep + + ldr r4, =S3C2410_REFRESH + ldr r5, =S3C2410_MISCCR + ldr r6, =S3C2410_CLKCON + ldr r7, [ r4 ] @ get REFRESH (and ensure in TLB) + ldr r8, [ r5 ] @ get MISCCR (and ensure in TLB) + ldr r9, [ r6 ] @ get CLKCON (and ensure in TLB) + + orr r7, r7, #S3C2410_REFRESH_SELF @ SDRAM sleep command + orr r8, r8, #S3C2410_MISCCR_SDSLEEP @ SDRAM power-down signals + orr r9, r9, #S3C2410_CLKCON_POWER @ power down command + + teq pc, #0 @ first as a trial-run to load cache + bl s3c2410_do_sleep + teq r0, r0 @ now do it for real + b s3c2410_do_sleep @ + + @@ align next bit of code to cache line + .align 8 +s3c2410_do_sleep: + streq r7, [ r4 ] @ SDRAM sleep command + streq r8, [ r5 ] @ SDRAM power-down config + streq r9, [ r6 ] @ CPU sleep +1: beq 1b + mov pc, r14 + + @@ return to the caller, after having the MMU + @@ turned on, this restores the last bits from the + @@ stack +resume_with_mmu: + ldmfd sp!, { r4 - r12, pc } + + .ltorg + + @@ the next bits sit in the .data segment, even though they + @@ happen to be code... the s3c2410_sleep_save_phys needs to be + @@ accessed by the resume code before it can restore the MMU. + @@ This means that the variable has to be close enough for the + @@ code to read it... since the .text segment needs to be RO, + @@ the data segment can be the only place to put this code. + + .data + + .global s3c2410_sleep_save_phys +s3c2410_sleep_save_phys: + .word 0 + + /* s3c2410_cpu_resume + * + * resume code entry for bootloader to call + * + * we must put this code here in the data segment as we have no + * other way of restoring the stack pointer after sleep, and we + * must not write to the code segment (code is read-only) + */ + +ENTRY(s3c2410_cpu_resume) + mov r0, #PSR_I_BIT | PSR_F_BIT | MODE_SVC + msr cpsr_c, r0 + + @@ load UART to allow us to print the two characters for + @@ resume debug + + mov r2, #S3C2410_PA_UART & 0xff000000 + orr r2, r2, #S3C2410_PA_UART & 0xff000 + +#ifdef CONFIG_DEBUG_RESUME + mov r3, #'L' + strb r3, [ r2, #S3C2410_UTXH ] +1001: + ldrb r14, [ r3, #S3C2410_UTRSTAT ] + tst r14, #S3C2410_UTRSTAT_TXE + beq 1001b +#endif /* CONFIG_DEBUG_RESUME */ + + mov r1, #0 + mcr p15, 0, r1, c8, c7, 0 @@ invalidate I & D TLBs + mcr p15, 0, r1, c7, c7, 0 @@ invalidate I & D caches + + ldr r0, s3c2410_sleep_save_phys @ address of restore block + ldmia r0, { r4 - r13 } + + mcr p15, 0, r4, c15, c1, 0 @ CP access register + mcr p15, 0, r5, c13, c0, 0 @ PID + mcr p15, 0, r6, c3, c0, 0 @ Domain ID + mcr p15, 0, r7, c2, c0, 0 @ translation table base + mcr p15, 0, r8, c1, c1, 0 @ auxilliary control + +#ifdef CONFIG_DEBUG_RESUME + mov r3, #'R' + strb r3, [ r2, #S3C2410_UTXH ] +#endif + + ldr r2, =resume_with_mmu + mcr p15, 0, r9, c1, c0, 0 @ turn on MMU, etc + nop @ second-to-last before mmu + mov pc, r2 @ go back to virtual address + + .ltorg