1 files changed, 234 insertions, 0 deletions

diff --git a/drivers/misc/hdpuftrs/hdpu_cpustate.c b/drivers/misc/hdpuftrs/hdpu_cpustate.c
new file mode 100644
index 000000000000..7501fab349e4
--- /dev/null
+++ b/drivers/misc/hdpuftrs/hdpu_cpustate.c
@@ -0,0 +1,234 @@
+/*
+ *      Sky CPU State Driver
+ *
+ *      Copyright (C) 2002 Brian Waite
+ *
+ *      This driver allows use of the CPU state bits
+ *      It exports the /dev/sky_cpustate and also
+ *      /proc/sky_cpustate pseudo-file for status information.
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/miscdevice.h>
+#include <linux/pci.h>
+#include <linux/proc_fs.h>
+#include <linux/device.h>
+#include <asm/uaccess.h>
+#include <linux/hdpu_features.h>
+
+#define SKY_CPUSTATE_VERSION            "1.1"
+
+static int hdpu_cpustate_probe(struct device *ddev);
+static int hdpu_cpustate_remove(struct device *ddev);
+
+struct cpustate_t cpustate;
+
+static int cpustate_get_ref(int excl)
+{
+
+        int retval = -EBUSY;
+
+        spin_lock(&cpustate.lock);
+
+        if (cpustate.excl)
+                goto out_busy;
+
+        if (excl) {
+                if (cpustate.open_count)
+                        goto out_busy;
+                cpustate.excl = 1;
+        }
+
+        cpustate.open_count++;
+        retval = 0;
+
+      out_busy:
+        spin_unlock(&cpustate.lock);
+        return retval;
+}
+
+static int cpustate_free_ref(void)
+{
+
+        spin_lock(&cpustate.lock);
+
+        cpustate.excl = 0;
+        cpustate.open_count--;
+
+        spin_unlock(&cpustate.lock);
+        return 0;
+}
+
+unsigned char cpustate_get_state(void)
+{
+
+        return cpustate.cached_val;
+}
+
+void cpustate_set_state(unsigned char new_state)
+{
+        unsigned int state = (new_state << 21);
+
+#ifdef DEBUG_CPUSTATE
+        printk("CPUSTATE -> 0x%x\n", new_state);
+#endif
+        spin_lock(&cpustate.lock);
+        cpustate.cached_val = new_state;
+        writel((0xff << 21), cpustate.clr_addr);
+        writel(state, cpustate.set_addr);
+        spin_unlock(&cpustate.lock);
+}
+
+/*
+ *      Now all the various file operations that we export.
+ */
+
+static ssize_t cpustate_read(struct file *file, char *buf,
+                             size_t count, loff_t * ppos)
+{
+        unsigned char data;
+
+        if (count < 0)
+                return -EFAULT;
+        if (count == 0)
+                return 0;
+
+        data = cpustate_get_state();
+        if (copy_to_user(buf, &data, sizeof(unsigned char)))
+                return -EFAULT;
+        return sizeof(unsigned char);
+}
+
+static ssize_t cpustate_write(struct file *file, const char *buf,
+                              size_t count, loff_t * ppos)
+{
+        unsigned char data;
+
+        if (count < 0)
+                return -EFAULT;
+
+        if (count == 0)
+                return 0;
+
+        if (copy_from_user((unsigned char *)&data, buf, sizeof(unsigned char)))
+                return -EFAULT;
+
+        cpustate_set_state(data);
+        return sizeof(unsigned char);
+}
+
+static int cpustate_open(struct inode *inode, struct file *file)
+{
+        return cpustate_get_ref((file->f_flags & O_EXCL));
+}
+
+static int cpustate_release(struct inode *inode, struct file *file)
+{
+        return cpustate_free_ref();
+}
+
+/*
+ *      Info exported via "/proc/sky_cpustate".
+ */
+static int cpustate_read_proc(char *page, char **start, off_t off,
+                              int count, int *eof, void *data)
+{
+        char *p = page;
+        int len = 0;
+
+        p += sprintf(p, "CPU State: %04x\n", cpustate_get_state());
+        len = p - page;
+
+        if (len <= off + count)
+                *eof = 1;
+        *start = page + off;
+        len -= off;
+        if (len > count)
+                len = count;
+        if (len < 0)
+                len = 0;
+        return len;
+}
+
+static struct device_driver hdpu_cpustate_driver = {
+        .name = HDPU_CPUSTATE_NAME,
+        .bus = &platform_bus_type,
+        .probe = hdpu_cpustate_probe,
+        .remove = hdpu_cpustate_remove,
+};
+
+/*
+ *      The various file operations we support.
+ */
+static struct file_operations cpustate_fops = {
+      owner:THIS_MODULE,
+      open:cpustate_open,
+      release:cpustate_release,
+      read:cpustate_read,
+      write:cpustate_write,
+      fasync:NULL,
+      poll:NULL,
+      ioctl:NULL,
+      llseek:no_llseek,
+
+};
+
+static struct miscdevice cpustate_dev = {
+        MISC_DYNAMIC_MINOR,
+        "sky_cpustate",
+        &cpustate_fops
+};
+
+static int hdpu_cpustate_probe(struct device *ddev)
+{
+        struct platform_device *pdev = to_platform_device(ddev);
+        struct resource *res;
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        cpustate.set_addr = (unsigned long *)res->start;
+        cpustate.clr_addr = (unsigned long *)res->end - 1;
+
+        misc_register(&cpustate_dev);
+        create_proc_read_entry("sky_cpustate", 0, 0, cpustate_read_proc, NULL);
+
+        printk(KERN_INFO "Sky CPU State Driver v" SKY_CPUSTATE_VERSION "\n");
+        return 0;
+}
+static int hdpu_cpustate_remove(struct device *ddev)
+{
+
+        cpustate.set_addr = 0;
+        cpustate.clr_addr = 0;
+
+        remove_proc_entry("sky_cpustate", NULL);
+        misc_deregister(&cpustate_dev);
+        return 0;
+
+}
+
+static int __init cpustate_init(void)
+{
+        int rc;
+        rc = driver_register(&hdpu_cpustate_driver);
+        return rc;
+}
+
+static void __exit cpustate_exit(void)
+{
+        driver_unregister(&hdpu_cpustate_driver);
+}
+
+module_init(cpustate_init);
+module_exit(cpustate_exit);
+
+MODULE_AUTHOR("Brian Waite");
+MODULE_LICENSE("GPL");