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-rw-r--r--arch/arm/mach-s3c/pm.c196
1 files changed, 196 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c/pm.c b/arch/arm/mach-s3c/pm.c
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index 0000000000..5698cbceaf
--- /dev/null
+++ b/arch/arm/mach-s3c/pm.c
@@ -0,0 +1,196 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright 2008 Openmoko, Inc.
+// Copyright 2004-2008 Simtec Electronics
+// Ben Dooks <ben@simtec.co.uk>
+// http://armlinux.simtec.co.uk/
+//
+// S3C common power management (suspend to ram) support.
+
+#include <linux/init.h>
+#include <linux/suspend.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/serial_s3c.h>
+#include <linux/io.h>
+
+#include <asm/cacheflush.h>
+#include <asm/suspend.h>
+
+#include "map.h"
+#include "regs-clock.h"
+#include "regs-irq.h"
+#include "irqs.h"
+
+#include <asm/irq.h>
+
+#include "cpu.h"
+#include "pm.h"
+#include "pm-core.h"
+
+/* for external use */
+
+unsigned long s3c_pm_flags;
+
+/* The IRQ ext-int code goes here, it is too small to currently bother
+ * with its own file. */
+
+unsigned long s3c_irqwake_intmask = 0xffffffffL;
+unsigned long s3c_irqwake_eintmask = 0xffffffffL;
+
+int s3c_irqext_wake(struct irq_data *data, unsigned int state)
+{
+ unsigned long bit = 1L << IRQ_EINT_BIT(data->irq);
+
+ if (!(s3c_irqwake_eintallow & bit))
+ return -ENOENT;
+
+ printk(KERN_INFO "wake %s for irq %d\n",
+ state ? "enabled" : "disabled", data->irq);
+
+ if (!state)
+ s3c_irqwake_eintmask |= bit;
+ else
+ s3c_irqwake_eintmask &= ~bit;
+
+ return 0;
+}
+
+void (*pm_cpu_prep)(void);
+int (*pm_cpu_sleep)(unsigned long);
+
+#define any_allowed(mask, allow) (((mask) & (allow)) != (allow))
+
+/* s3c_pm_enter
+ *
+ * central control for sleep/resume process
+*/
+
+static int s3c_pm_enter(suspend_state_t state)
+{
+ int ret;
+ /* ensure the debug is initialised (if enabled) */
+ s3c_pm_debug_init_uart();
+
+ S3C_PMDBG("%s(%d)\n", __func__, state);
+
+ if (pm_cpu_prep == NULL || pm_cpu_sleep == NULL) {
+ printk(KERN_ERR "%s: error: no cpu sleep function\n", __func__);
+ 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 (!of_have_populated_dt() &&
+ !any_allowed(s3c_irqwake_intmask, s3c_irqwake_intallow) &&
+ !any_allowed(s3c_irqwake_eintmask, s3c_irqwake_eintallow)) {
+ printk(KERN_ERR "%s: No wake-up sources!\n", __func__);
+ printk(KERN_ERR "%s: Aborting sleep\n", __func__);
+ return -EINVAL;
+ }
+
+ /* save all necessary core registers not covered by the drivers */
+
+ if (!of_have_populated_dt()) {
+ samsung_pm_save_gpios();
+ samsung_pm_saved_gpios();
+ }
+
+ s3c_pm_save_uarts(false);
+ s3c_pm_save_core();
+
+ /* set the irq configuration for wake */
+
+ s3c_pm_configure_extint();
+
+ S3C_PMDBG("sleep: irq wakeup masks: %08lx,%08lx\n",
+ s3c_irqwake_intmask, s3c_irqwake_eintmask);
+
+ s3c_pm_arch_prepare_irqs();
+
+ /* call cpu specific preparation */
+
+ pm_cpu_prep();
+
+ /* flush cache back to ram */
+
+ flush_cache_all();
+
+ s3c_pm_check_store();
+
+ /* send the cpu to sleep... */
+
+ s3c_pm_arch_stop_clocks();
+
+ /* this will also act as our return point from when
+ * we resume as it saves its own register state and restores it
+ * during the resume. */
+
+ ret = cpu_suspend(0, pm_cpu_sleep);
+ if (ret)
+ return ret;
+
+ /* restore the system state */
+
+ s3c_pm_restore_core();
+ s3c_pm_restore_uarts(false);
+
+ if (!of_have_populated_dt()) {
+ samsung_pm_restore_gpios();
+ s3c_pm_restored_gpios();
+ }
+
+ s3c_pm_debug_init_uart();
+
+ /* check what irq (if any) restored the system */
+
+ s3c_pm_arch_show_resume_irqs();
+
+ S3C_PMDBG("%s: post sleep, preparing to return\n", __func__);
+
+ s3c_pm_check_restore();
+
+ /* ok, let's return from sleep */
+
+ S3C_PMDBG("S3C PM Resume (post-restore)\n");
+ return 0;
+}
+
+static int s3c_pm_prepare(void)
+{
+ /* prepare check area if configured */
+
+ s3c_pm_check_prepare();
+ return 0;
+}
+
+static void s3c_pm_finish(void)
+{
+ s3c_pm_check_cleanup();
+}
+
+static const struct platform_suspend_ops s3c_pm_ops = {
+ .enter = s3c_pm_enter,
+ .prepare = s3c_pm_prepare,
+ .finish = s3c_pm_finish,
+ .valid = suspend_valid_only_mem,
+};
+
+/* s3c_pm_init
+ *
+ * Attach the power management functions. This should be called
+ * from the board specific initialisation if the board supports
+ * it.
+*/
+
+int __init s3c_pm_init(void)
+{
+ printk("S3C Power Management, Copyright 2004 Simtec Electronics\n");
+
+ suspend_set_ops(&s3c_pm_ops);
+ return 0;
+}