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Diffstat (limited to 'target/linux/amazon-2.6/files/drivers/char/amazon_wdt.c')
-rw-r--r--target/linux/amazon-2.6/files/drivers/char/amazon_wdt.c261
1 files changed, 261 insertions, 0 deletions
diff --git a/target/linux/amazon-2.6/files/drivers/char/amazon_wdt.c b/target/linux/amazon-2.6/files/drivers/char/amazon_wdt.c
new file mode 100644
index 0000000000..c6a90f07b2
--- /dev/null
+++ b/target/linux/amazon-2.6/files/drivers/char/amazon_wdt.c
@@ -0,0 +1,261 @@
+/*
+ * Infineon AP DC COM Amazon WDT driver
+ * Copyright 2004 Wu Qi Ming <gokimi@msn.com>
+ * All rights reserved
+ */
+#if defined(MODVERSIONS)
+#include <linux/modversions.h>
+#endif
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/timer.h>
+#include <linux/fs.h>
+#include <linux/errno.h>
+#include <linux/proc_fs.h>
+#include <linux/stat.h>
+#include <linux/tty.h>
+#include <linux/selection.h>
+#include <linux/kmod.h>
+#include <linux/vmalloc.h>
+#include <linux/kdev_t.h>
+#include <linux/ioctl.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/amazon/amazon.h>
+#include <asm/amazon/amazon_wdt.h>
+
+#define AMAZON_WDT_EMSG(fmt, args...) printk( "%s: " fmt, __FUNCTION__ , ##args)
+
+extern unsigned int amazon_get_fpi_hz(void);
+
+/* forward declarations for _fops */
+static ssize_t wdt_read(struct file *file, char *buf, size_t count, loff_t *offset);
+static ssize_t wdt_write(struct file *file, const char *buf, size_t count, loff_t *offset);
+static int wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
+static int wdt_open(struct inode *inode, struct file *file);
+static int wdt_release(struct inode *inode, struct file *file);
+static int wdt_proc_read(char *buf, char **start, off_t offset,int count, int *eof, void *data);
+
+
+static struct file_operations wdt_fops = {
+ read:wdt_read,
+ write:wdt_write,
+ ioctl:wdt_ioctl,
+ open:wdt_open,
+ release:wdt_release,
+};
+
+/* data */
+static struct wdt_dev *amazon_wdt_dev;
+static struct proc_dir_entry* amazon_wdt_dir;
+static int occupied=0;
+
+
+/* Brief: enable WDT
+ * Parameter:
+ timeout: time interval for WDT
+ * Return:
+ 0 OK
+ EINVAL
+ * Describes:
+ 1. Password Access
+ 2. Modify Access (change ENDINIT => 0)
+ 3. Change WDT_CON1 (enable WDT)
+ 4. Password Access again
+ 5. Modify Access (change ENDINIT => 1)
+ */
+int wdt_enable(int timeout)
+{
+ u32 hard_psw,ffpi;
+ int reload_value, divider=0;
+
+ ffpi = amazon_get_fpi_hz();
+
+ divider = 1;
+ if((reload_value=65536-timeout*ffpi/256)<0){
+ divider = 0;
+ reload_value=65536-timeout*ffpi/16384;
+ }
+ if (reload_value < 0){
+ AMAZON_WDT_EMSG("timeout too large %d\n", timeout);
+ return -EINVAL;
+ }
+
+ AMAZON_WDT_EMSG("timeout:%d reload_value: %8x\n", timeout, reload_value);
+
+ hard_psw=(AMAZON_WDT_REG32(AMAZON_WDT_CON0)&0xffffff01)+(AMAZON_WDT_REG32(AMAZON_WDT_CON1)&0xc)+ 0xf0;
+ AMAZON_WDT_REG32(AMAZON_WDT_CON0)=hard_psw;
+ wmb();
+
+ AMAZON_WDT_REG32(AMAZON_WDT_CON0)=(hard_psw&0xff00)+(reload_value<<16)+0xf2;
+ wmb();
+
+ AMAZON_WDT_REG32(AMAZON_WDT_CON1)=divider<<2;
+ wmb();
+
+ hard_psw=(AMAZON_WDT_REG32(AMAZON_WDT_CON0)&0xffffff01)+(AMAZON_WDT_REG32(AMAZON_WDT_CON1)&0xc)+ 0xf0;
+ AMAZON_WDT_REG32(AMAZON_WDT_CON0)=hard_psw;
+
+ wmb();
+ AMAZON_WDT_REG32(AMAZON_WDT_CON0)=(AMAZON_WDT_REG32(AMAZON_WDT_CON0)&0xffffff00)+0xf3;
+ wmb();
+ return 0;
+}
+
+/* Brief: Disable/stop WDT
+ */
+void wdt_disable(void)
+{
+ u32 hard_psw=0;
+
+ hard_psw=(AMAZON_WDT_REG32(AMAZON_WDT_CON0)&0xffffff01)+(AMAZON_WDT_REG32(AMAZON_WDT_CON1)&0xc)+ 0xf0;
+ AMAZON_WDT_REG32(AMAZON_WDT_CON0)=hard_psw;
+ wmb();
+
+ AMAZON_WDT_REG32(AMAZON_WDT_CON0)=(AMAZON_WDT_REG32(AMAZON_WDT_CON0)&0xffffff00)+0xf2;
+ wmb();
+
+ AMAZON_WDT_REG32(AMAZON_WDT_CON1)|=8;
+ wmb();
+
+ hard_psw=(AMAZON_WDT_REG32(AMAZON_WDT_CON0)&0xffffff01)+(AMAZON_WDT_REG32(AMAZON_WDT_CON1)&0xc)+ 0xf0;
+ AMAZON_WDT_REG32(AMAZON_WDT_CON0)=hard_psw;
+ wmb();
+
+ AMAZON_WDT_REG32(AMAZON_WDT_CON0)=(AMAZON_WDT_REG32(AMAZON_WDT_CON0)&0xffffff00)+0xf3;
+ wmb();
+
+ return;
+}
+
+static int wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
+{
+ int result=0;
+ static int timeout=-1;
+
+ switch(cmd){
+ case AMAZON_WDT_IOC_START:
+ AMAZON_WDT_DMSG("enable watch dog timer!\n");
+ if ( copy_from_user((void*)&timeout, (void*)arg, sizeof (int)) ){
+ AMAZON_WDT_EMSG("invalid argument\n");
+ result=-EINVAL;
+ }else{
+ if ((result = wdt_enable(timeout)) < 0){
+ timeout = -1;
+ }
+ }
+ break;
+ case AMAZON_WDT_IOC_STOP:
+ AMAZON_WDT_DMSG("disable watch dog timer\n");
+ timeout = -1;
+ wdt_disable();
+
+ break;
+ case AMAZON_WDT_IOC_PING:
+ if (timeout <0 ){
+ result = -EIO;
+ }else{
+ result = wdt_enable(timeout);
+ }
+ }
+ return result;
+}
+
+static ssize_t wdt_read(struct file *file, char *buf, size_t count, loff_t *offset)
+{
+ return 0;
+}
+
+static ssize_t wdt_write(struct file *file, const char *buf, size_t count, loff_t *offset)
+{
+ return count;
+}
+
+static int wdt_open(struct inode *inode, struct file *file)
+{
+ AMAZON_WDT_DMSG("wdt_open\n");
+
+ if (occupied == 1) return -EBUSY;
+ occupied = 1;
+
+ return 0;
+}
+
+static int wdt_release(struct inode *inode, struct file *file)
+{
+ AMAZON_WDT_DMSG("wdt_release\n");
+
+ occupied = 0;
+ return 0;
+}
+
+
+int wdt_register_proc_read(char *buf, char **start, off_t offset,
+ int count, int *eof, void *data)
+{
+ int len=0;
+ printk("wdt_registers:\n");
+ len+=sprintf(buf+len,"NMISR: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_WDT_NMISR));
+ len+=sprintf(buf+len,"RST_REQ: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_RST_REQ));
+ len+=sprintf(buf+len,"RST_SR: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_RST_SR));
+ len+=sprintf(buf+len,"WDT_CON0: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_WDT_CON0));
+ len+=sprintf(buf+len,"WDT_CON1: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_WDT_CON1));
+ len+=sprintf(buf+len,"WDT_SR: 0x%08x\n",AMAZON_WDT_REG32(AMAZON_WDT_SR));
+ *eof = 1;
+ return len;
+}
+
+
+int __init amazon_wdt_init_module(void)
+{
+ int result=0;
+
+ amazon_wdt_dev = (wdt_dev*)kmalloc(sizeof(wdt_dev),GFP_KERNEL);
+ if (amazon_wdt_dev == NULL){
+ return -ENOMEM;
+ }
+ memset(amazon_wdt_dev,0,sizeof(wdt_dev));
+
+ amazon_wdt_dev->major=result;
+ strcpy(amazon_wdt_dev->name,"wdt");
+
+ result = register_chrdev(0,amazon_wdt_dev->name,&wdt_fops);
+ if (result < 0) {
+ AMAZON_WDT_EMSG("cannot register device\n");
+ kfree(amazon_wdt_dev);
+ return result;
+ }
+
+ amazon_wdt_dir=proc_mkdir("amazon_wdt",NULL);
+ create_proc_read_entry("wdt_register",
+ 0,
+ amazon_wdt_dir,
+ wdt_register_proc_read,
+ NULL);
+
+ occupied=0;
+ return 0;
+}
+
+void amazon_wdt_cleanup_module(void)
+{
+ unregister_chrdev(amazon_wdt_dev->major,amazon_wdt_dev->name);
+ kfree(amazon_wdt_dev);
+ remove_proc_entry("wdt_register",amazon_wdt_dir);
+ remove_proc_entry("amazon_wdt",NULL);
+ AMAZON_WDT_DMSG("unloaded\n");
+ return;
+}
+
+MODULE_LICENSE ("GPL");
+MODULE_AUTHOR("Infineon IFAP DC COM");
+MODULE_DESCRIPTION("AMAZON WDT driver");
+
+module_init(amazon_wdt_init_module);
+module_exit(amazon_wdt_cleanup_module);
+
generated by cgit v1.2.3 (git 2.25.1) at 2025-01-27 11:15:00 +0000