v4.19.13 snapshot.
diff --git a/arch/sparc/kernel/apc.c b/arch/sparc/kernel/apc.c
new file mode 100644
index 0000000..ecd05bc
--- /dev/null
+++ b/arch/sparc/kernel/apc.c
@@ -0,0 +1,196 @@
+// SPDX-License-Identifier: GPL-2.0
+/* apc - Driver implementation for power management functions
+ * of Aurora Personality Chip (APC) on SPARCstation-4/5 and
+ * derivatives.
+ *
+ * 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/miscdevice.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/apc.h>
+#include <asm/processor.h>
+
+/* Debugging
+ *
+ * #define APC_DEBUG_LED
+ */
+
+#define APC_MINOR MISC_DYNAMIC_MINOR
+#define APC_OBPNAME "power-management"
+#define APC_DEVNAME "apc"
+
+static u8 __iomem *regs;
+static int apc_no_idle = 0;
+
+#define apc_readb(offs) (sbus_readb(regs+offs))
+#define apc_writeb(val, offs) (sbus_writeb(val, regs+offs))
+
+/* Specify "apc=noidle" on the kernel command line to
+ * disable APC CPU standby support. Certain prototype
+ * systems (SPARCstation-Fox) do not play well with APC
+ * CPU idle, so disable this if your system has APC and
+ * crashes randomly.
+ */
+static int __init apc_setup(char *str)
+{
+ if(!strncmp(str, "noidle", strlen("noidle"))) {
+ apc_no_idle = 1;
+ return 1;
+ }
+ return 0;
+}
+__setup("apc=", apc_setup);
+
+/*
+ * CPU idle callback function
+ * See .../arch/sparc/kernel/process.c
+ */
+static void apc_swift_idle(void)
+{
+#ifdef APC_DEBUG_LED
+ set_auxio(0x00, AUXIO_LED);
+#endif
+
+ apc_writeb(apc_readb(APC_IDLE_REG) | APC_IDLE_ON, APC_IDLE_REG);
+
+#ifdef APC_DEBUG_LED
+ set_auxio(AUXIO_LED, 0x00);
+#endif
+}
+
+static inline void apc_free(struct platform_device *op)
+{
+ of_iounmap(&op->resource[0], regs, resource_size(&op->resource[0]));
+}
+
+static int apc_open(struct inode *inode, struct file *f)
+{
+ return 0;
+}
+
+static int apc_release(struct inode *inode, struct file *f)
+{
+ return 0;
+}
+
+static long apc_ioctl(struct file *f, unsigned int cmd, unsigned long __arg)
+{
+ __u8 inarg, __user *arg = (__u8 __user *) __arg;
+
+ switch (cmd) {
+ case APCIOCGFANCTL:
+ if (put_user(apc_readb(APC_FANCTL_REG) & APC_REGMASK, arg))
+ return -EFAULT;
+ break;
+
+ case APCIOCGCPWR:
+ if (put_user(apc_readb(APC_CPOWER_REG) & APC_REGMASK, arg))
+ return -EFAULT;
+ break;
+
+ case APCIOCGBPORT:
+ if (put_user(apc_readb(APC_BPORT_REG) & APC_BPMASK, arg))
+ return -EFAULT;
+ break;
+
+ case APCIOCSFANCTL:
+ if (get_user(inarg, arg))
+ return -EFAULT;
+ apc_writeb(inarg & APC_REGMASK, APC_FANCTL_REG);
+ break;
+
+ case APCIOCSCPWR:
+ if (get_user(inarg, arg))
+ return -EFAULT;
+ apc_writeb(inarg & APC_REGMASK, APC_CPOWER_REG);
+ break;
+
+ case APCIOCSBPORT:
+ if (get_user(inarg, arg))
+ return -EFAULT;
+ apc_writeb(inarg & APC_BPMASK, APC_BPORT_REG);
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static const struct file_operations apc_fops = {
+ .unlocked_ioctl = apc_ioctl,
+ .open = apc_open,
+ .release = apc_release,
+ .llseek = noop_llseek,
+};
+
+static struct miscdevice apc_miscdev = { APC_MINOR, APC_DEVNAME, &apc_fops };
+
+static int apc_probe(struct platform_device *op)
+{
+ int err;
+
+ regs = of_ioremap(&op->resource[0], 0,
+ resource_size(&op->resource[0]), APC_OBPNAME);
+ if (!regs) {
+ printk(KERN_ERR "%s: unable to map registers\n", APC_DEVNAME);
+ return -ENODEV;
+ }
+
+ err = misc_register(&apc_miscdev);
+ if (err) {
+ printk(KERN_ERR "%s: unable to register device\n", APC_DEVNAME);
+ apc_free(op);
+ return -ENODEV;
+ }
+
+ /* Assign power management IDLE handler */
+ if (!apc_no_idle)
+ sparc_idle = apc_swift_idle;
+
+ printk(KERN_INFO "%s: power management initialized%s\n",
+ APC_DEVNAME, apc_no_idle ? " (CPU idle disabled)" : "");
+
+ return 0;
+}
+
+static const struct of_device_id apc_match[] = {
+ {
+ .name = APC_OBPNAME,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, apc_match);
+
+static struct platform_driver apc_driver = {
+ .driver = {
+ .name = "apc",
+ .of_match_table = apc_match,
+ },
+ .probe = apc_probe,
+};
+
+static int __init apc_init(void)
+{
+ return platform_driver_register(&apc_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(apc_init);