v4.19.13 snapshot.
diff --git a/arch/arm/mach-s3c64xx/irq-pm.c b/arch/arm/mach-s3c64xx/irq-pm.c
new file mode 100644
index 0000000..31b2211
--- /dev/null
+++ b/arch/arm/mach-s3c64xx/irq-pm.c
@@ -0,0 +1,119 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright 2008 Openmoko, Inc.
+// Copyright 2008 Simtec Electronics
+//      Ben Dooks <ben@simtec.co.uk>
+//      http://armlinux.simtec.co.uk/
+//
+// S3C64XX - Interrupt handling Power Management
+
+/*
+ * NOTE: Code in this file is not used when booting with Device Tree support.
+ */
+
+#include <linux/kernel.h>
+#include <linux/syscore_ops.h>
+#include <linux/interrupt.h>
+#include <linux/serial_core.h>
+#include <linux/serial_s3c.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/of.h>
+
+#include <mach/map.h>
+
+#include <mach/regs-gpio.h>
+#include <plat/cpu.h>
+#include <plat/pm.h>
+
+/* We handled all the IRQ types in this code, to save having to make several
+ * small files to handle each different type separately. Having the EINT_GRP
+ * code here shouldn't be as much bloat as the IRQ table space needed when
+ * they are enabled. The added benefit is we ensure that these registers are
+ * in the same state as we suspended.
+ */
+
+static struct sleep_save irq_save[] = {
+	SAVE_ITEM(S3C64XX_PRIORITY),
+	SAVE_ITEM(S3C64XX_EINT0CON0),
+	SAVE_ITEM(S3C64XX_EINT0CON1),
+	SAVE_ITEM(S3C64XX_EINT0FLTCON0),
+	SAVE_ITEM(S3C64XX_EINT0FLTCON1),
+	SAVE_ITEM(S3C64XX_EINT0FLTCON2),
+	SAVE_ITEM(S3C64XX_EINT0FLTCON3),
+	SAVE_ITEM(S3C64XX_EINT0MASK),
+};
+
+static struct irq_grp_save {
+	u32	fltcon;
+	u32	con;
+	u32	mask;
+} eint_grp_save[5];
+
+#ifndef CONFIG_SERIAL_SAMSUNG_UARTS
+#define SERIAL_SAMSUNG_UARTS 0
+#else
+#define	SERIAL_SAMSUNG_UARTS CONFIG_SERIAL_SAMSUNG_UARTS
+#endif
+
+static u32 irq_uart_mask[SERIAL_SAMSUNG_UARTS];
+
+static int s3c64xx_irq_pm_suspend(void)
+{
+	struct irq_grp_save *grp = eint_grp_save;
+	int i;
+
+	S3C_PMDBG("%s: suspending IRQs\n", __func__);
+
+	s3c_pm_do_save(irq_save, ARRAY_SIZE(irq_save));
+
+	for (i = 0; i < SERIAL_SAMSUNG_UARTS; i++)
+		irq_uart_mask[i] = __raw_readl(S3C_VA_UARTx(i) + S3C64XX_UINTM);
+
+	for (i = 0; i < ARRAY_SIZE(eint_grp_save); i++, grp++) {
+		grp->con = __raw_readl(S3C64XX_EINT12CON + (i * 4));
+		grp->mask = __raw_readl(S3C64XX_EINT12MASK + (i * 4));
+		grp->fltcon = __raw_readl(S3C64XX_EINT12FLTCON + (i * 4));
+	}
+
+	return 0;
+}
+
+static void s3c64xx_irq_pm_resume(void)
+{
+	struct irq_grp_save *grp = eint_grp_save;
+	int i;
+
+	S3C_PMDBG("%s: resuming IRQs\n", __func__);
+
+	s3c_pm_do_restore(irq_save, ARRAY_SIZE(irq_save));
+
+	for (i = 0; i < SERIAL_SAMSUNG_UARTS; i++)
+		__raw_writel(irq_uart_mask[i], S3C_VA_UARTx(i) + S3C64XX_UINTM);
+
+	for (i = 0; i < ARRAY_SIZE(eint_grp_save); i++, grp++) {
+		__raw_writel(grp->con, S3C64XX_EINT12CON + (i * 4));
+		__raw_writel(grp->mask, S3C64XX_EINT12MASK + (i * 4));
+		__raw_writel(grp->fltcon, S3C64XX_EINT12FLTCON + (i * 4));
+	}
+
+	S3C_PMDBG("%s: IRQ configuration restored\n", __func__);
+}
+
+static struct syscore_ops s3c64xx_irq_syscore_ops = {
+	.suspend = s3c64xx_irq_pm_suspend,
+	.resume	 = s3c64xx_irq_pm_resume,
+};
+
+static __init int s3c64xx_syscore_init(void)
+{
+	/* Appropriate drivers (pinctrl, uart) handle this when using DT. */
+	if (of_have_populated_dt() || !soc_is_s3c64xx())
+		return 0;
+
+	register_syscore_ops(&s3c64xx_irq_syscore_ops);
+
+	return 0;
+}
+
+core_initcall(s3c64xx_syscore_init);