v4.19.13 snapshot.
diff --git a/arch/sparc/kernel/pmc.c b/arch/sparc/kernel/pmc.c
new file mode 100644
index 0000000..b5c1eb3
--- /dev/null
+++ b/arch/sparc/kernel/pmc.c
@@ -0,0 +1,100 @@
+// SPDX-License-Identifier: GPL-2.0
+/* pmc - Driver implementation for power management functions
+ * of Power Management Controller (PMC) on SPARCstation-Voyager.
+ *
+ * Copyright (c) 2002 Eric Brower (ebrower@usa.net)
+ */
+
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/pm.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/module.h>
+
+#include <asm/io.h>
+#include <asm/oplib.h>
+#include <linux/uaccess.h>
+#include <asm/auxio.h>
+#include <asm/processor.h>
+
+/* Debug
+ *
+ * #define PMC_DEBUG_LED
+ * #define PMC_NO_IDLE
+ */
+
+#define PMC_OBPNAME "SUNW,pmc"
+#define PMC_DEVNAME "pmc"
+
+#define PMC_IDLE_REG 0x00
+#define PMC_IDLE_ON 0x01
+
+static u8 __iomem *regs;
+
+#define pmc_readb(offs) (sbus_readb(regs+offs))
+#define pmc_writeb(val, offs) (sbus_writeb(val, regs+offs))
+
+/*
+ * CPU idle callback function
+ * See .../arch/sparc/kernel/process.c
+ */
+static void pmc_swift_idle(void)
+{
+#ifdef PMC_DEBUG_LED
+ set_auxio(0x00, AUXIO_LED);
+#endif
+
+ pmc_writeb(pmc_readb(PMC_IDLE_REG) | PMC_IDLE_ON, PMC_IDLE_REG);
+
+#ifdef PMC_DEBUG_LED
+ set_auxio(AUXIO_LED, 0x00);
+#endif
+}
+
+static int pmc_probe(struct platform_device *op)
+{
+ regs = of_ioremap(&op->resource[0], 0,
+ resource_size(&op->resource[0]), PMC_OBPNAME);
+ if (!regs) {
+ printk(KERN_ERR "%s: unable to map registers\n", PMC_DEVNAME);
+ return -ENODEV;
+ }
+
+#ifndef PMC_NO_IDLE
+ /* Assign power management IDLE handler */
+ sparc_idle = pmc_swift_idle;
+#endif
+
+ printk(KERN_INFO "%s: power management initialized\n", PMC_DEVNAME);
+ return 0;
+}
+
+static const struct of_device_id pmc_match[] = {
+ {
+ .name = PMC_OBPNAME,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, pmc_match);
+
+static struct platform_driver pmc_driver = {
+ .driver = {
+ .name = "pmc",
+ .of_match_table = pmc_match,
+ },
+ .probe = pmc_probe,
+};
+
+static int __init pmc_init(void)
+{
+ return platform_driver_register(&pmc_driver);
+}
+
+/* This driver is not critical to the boot process
+ * and is easiest to ioremap when SBus is already
+ * initialized, so we install ourselves thusly:
+ */
+__initcall(pmc_init);