[ARM] S3C: Move plat-s3c24xx pm.c support into plat-s3c

Move parts of the core and debug suspend code into the
plat-s3c for use with the new s3c64xx code.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>

2 files changed, 238 insertions, 0 deletions

diff --git a/arch/arm/plat-s3c/include/plat/pm.h b/arch/arm/plat-s3c/include/plat/pm.h
index 95c2612d4976..42c75e6d2ba5 100644
--- a/arch/arm/plat-s3c/include/plat/pm.h
+++ b/arch/arm/plat-s3c/include/plat/pm.h
@@ -113,3 +113,30 @@ extern void s3c_pm_check_store(void);
 #define s3c_pm_check_restore() do { } while(0)
 #define s3c_pm_check_store()   do { } while(0)
 #endif
+
+/**
+ * s3c_pm_configure_extint() - ensure pins are correctly set for IRQ
+ *
+ * Setup all the necessary GPIO pins for waking the system on external
+ * interrupt.
+ */
+extern void s3c_pm_configure_extint(void);
+
+/**
+ * s3c_pm_restore_gpios() - restore the state of the gpios after sleep.
+ *
+ * Restore the state of the GPIO pins after sleep, which may involve ensuring
+ * that we do not glitch the state of the pins from that the bootloader's
+ * resume code has done.
+*/
+extern void s3c_pm_restore_gpios(void);
+
+/**
+ * s3c_pm_save_gpios() - save the state of the GPIOs for restoring after sleep.
+ *
+ * Save the GPIO states for resotration on resume. See s3c_pm_restore_gpios().
+ */
+extern void s3c_pm_save_gpios(void);
+
+extern void s3c_pm_save_core(void);
+extern void s3c_pm_restore_core(void);
diff --git a/arch/arm/plat-s3c/pm.c b/arch/arm/plat-s3c/pm.c
index 122e9b91a7f4..fea58bea973d 100644
--- a/arch/arm/plat-s3c/pm.c
+++ b/arch/arm/plat-s3c/pm.c
@@ -15,14 +15,32 @@
 #include <linux/init.h>
 #include <linux/suspend.h>
 #include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/serial_core.h>
 #include <linux/io.h>
 
+#include <asm/cacheflush.h>
+#include <mach/hardware.h>
+
+#include <plat/regs-serial.h>
+#include <mach/regs-clock.h>
+#include <mach/regs-gpio.h>
+#include <mach/regs-mem.h>
+#include <mach/regs-irq.h>
+
 #include <plat/pm.h>
+#include <plat/pm-core.h>
 
 /* for external use */
 
 unsigned long s3c_pm_flags;
 
+/* Debug code:
+ *
+ * This code supports debug output to the low level UARTs for use on
+ * resume before the console layer is available.
+*/
+
 #ifdef CONFIG_S3C2410_PM_DEBUG
 extern void printascii(const char *);
 
@@ -37,8 +55,51 @@ void s3c_pm_dbg(const char *fmt, ...)
 
 	printascii(buff);
 }
+
+static inline void s3c_pm_debug_init(void)
+{
+	/* restart uart clocks so we can use them to output */
+	s3c_pm_debug_init_uart();
+}
+
+#else
+#define s3c_pm_debug_init() do { } while(0)
+
 #endif /* CONFIG_S3C2410_PM_DEBUG */
 
+/* Save the UART configurations if we are configured for debug. */
+
+#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(S3C_VA_UART0),
+	SAVE_UART(S3C_VA_UART1),
+#ifndef CONFIG_CPU_S3C2400
+	SAVE_UART(S3C_VA_UART2),
+#endif
+};
+
+static void s3c_pm_save_uart(void)
+{
+	s3c_pm_do_save(uart_save, ARRAY_SIZE(uart_save));
+}
+
+static void s3c_pm_restore_uart(void)
+{
+	s3c_pm_do_restore(uart_save, ARRAY_SIZE(uart_save));
+}
+#else
+static void s3c_pm_save_uart(void) { }
+static void s3c_pm_restore_uart(void) { }
+#endif
+
 
 /* helper functions to save and restore register state */
 
@@ -95,3 +156,153 @@ void s3c_pm_do_restore_core(struct sleep_save *ptr, int count)
 	for (; count > 0; count--, ptr++)
 		__raw_writel(ptr->val, ptr->reg);
 }
+
+/* s3c2410_pm_show_resume_irqs
+ *
+ * print any IRQs asserted at resume time (ie, we woke from)
+*/
+static void s3c_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<<i)) {
+			S3C_PMDBG("IRQ %d asserted at resume\n", start+i);
+		}
+	}
+}
+
+
+void (*pm_cpu_prep)(void);
+void (*pm_cpu_sleep)(void);
+
+#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)
+{
+	unsigned long regs_save[16];
+
+	/* ensure the debug is initialised (if enabled) */
+
+	s3c_pm_debug_init();
+
+	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 (!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;
+	}
+
+	/* prepare check area if configured */
+
+	s3c_pm_check_prepare();
+
+	/* store the physical address of the register recovery block */
+
+	s3c_sleep_save_phys = virt_to_phys(regs_save);
+
+	S3C_PMDBG("s3c_sleep_save_phys=0x%08lx\n", s3c_sleep_save_phys);
+
+	/* save all necessary core registers not covered by the drivers */
+
+	s3c_pm_save_gpios();
+	s3c_pm_save_uart();
+	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();
+
+	/* s3c2410_cpu_save will also act as our return point from when
+	 * we resume as it saves its own register state, so use the return
+	 * code to differentiate return from save and return from sleep */
+
+	if (s3c2410_cpu_save(regs_save) == 0) {
+		flush_cache_all();
+		pm_cpu_sleep();
+	}
+
+	/* restore the cpu state using the kernel's cpu init code. */
+
+	cpu_init();
+
+	/* restore the system state */
+
+	s3c_pm_restore_core();
+	s3c_pm_restore_uart();
+	s3c_pm_restore_gpios();
+
+	s3c_pm_debug_init();
+
+	/* 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 struct platform_suspend_ops s3c_pm_ops = {
+	.enter		= s3c_pm_enter,
+	.valid		= suspend_valid_only_mem,
+};
+
+/* 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("S3C Power Management, Copyright 2004 Simtec Electronics\n");
+
+	suspend_set_ops(&s3c_pm_ops);
+	return 0;
+}