xref: /OK3568_Linux_fs/u-boot/drivers/watchdog/xilinx_tb_wdt.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * Copyright (c) 2011-2013 Xilinx Inc.
3*4882a593Smuzhiyun  *
4*4882a593Smuzhiyun  * SPDX-License-Identifier:	GPL-2.0+
5*4882a593Smuzhiyun  */
6*4882a593Smuzhiyun 
7*4882a593Smuzhiyun #include <common.h>
8*4882a593Smuzhiyun #include <asm/io.h>
9*4882a593Smuzhiyun #include <asm/microblaze_intc.h>
10*4882a593Smuzhiyun #include <asm/processor.h>
11*4882a593Smuzhiyun #include <watchdog.h>
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #define XWT_CSR0_WRS_MASK	0x00000008 /* Reset status Mask */
14*4882a593Smuzhiyun #define XWT_CSR0_WDS_MASK	0x00000004 /* Timer state Mask */
15*4882a593Smuzhiyun #define XWT_CSR0_EWDT1_MASK	0x00000002 /* Enable bit 1 Mask*/
16*4882a593Smuzhiyun #define XWT_CSRX_EWDT2_MASK	0x00000001 /* Enable bit 2 Mask */
17*4882a593Smuzhiyun 
18*4882a593Smuzhiyun struct watchdog_regs {
19*4882a593Smuzhiyun 	u32 twcsr0; /* 0x0 */
20*4882a593Smuzhiyun 	u32 twcsr1; /* 0x4 */
21*4882a593Smuzhiyun 	u32 tbr; /* 0x8 */
22*4882a593Smuzhiyun };
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun static struct watchdog_regs *watchdog_base =
25*4882a593Smuzhiyun 			(struct watchdog_regs *)CONFIG_WATCHDOG_BASEADDR;
26*4882a593Smuzhiyun 
hw_watchdog_reset(void)27*4882a593Smuzhiyun void hw_watchdog_reset(void)
28*4882a593Smuzhiyun {
29*4882a593Smuzhiyun 	u32 reg;
30*4882a593Smuzhiyun 
31*4882a593Smuzhiyun 	/* Read the current contents of TCSR0 */
32*4882a593Smuzhiyun 	reg = readl(&watchdog_base->twcsr0);
33*4882a593Smuzhiyun 
34*4882a593Smuzhiyun 	/* Clear the watchdog WDS bit */
35*4882a593Smuzhiyun 	if (reg & (XWT_CSR0_EWDT1_MASK | XWT_CSRX_EWDT2_MASK))
36*4882a593Smuzhiyun 		writel(reg | XWT_CSR0_WDS_MASK, &watchdog_base->twcsr0);
37*4882a593Smuzhiyun }
38*4882a593Smuzhiyun 
hw_watchdog_disable(void)39*4882a593Smuzhiyun void hw_watchdog_disable(void)
40*4882a593Smuzhiyun {
41*4882a593Smuzhiyun 	u32 reg;
42*4882a593Smuzhiyun 
43*4882a593Smuzhiyun 	/* Read the current contents of TCSR0 */
44*4882a593Smuzhiyun 	reg = readl(&watchdog_base->twcsr0);
45*4882a593Smuzhiyun 
46*4882a593Smuzhiyun 	writel(reg & ~XWT_CSR0_EWDT1_MASK, &watchdog_base->twcsr0);
47*4882a593Smuzhiyun 	writel(~XWT_CSRX_EWDT2_MASK, &watchdog_base->twcsr1);
48*4882a593Smuzhiyun 
49*4882a593Smuzhiyun 	puts("Watchdog disabled!\n");
50*4882a593Smuzhiyun }
51*4882a593Smuzhiyun 
hw_watchdog_isr(void * arg)52*4882a593Smuzhiyun static void hw_watchdog_isr(void *arg)
53*4882a593Smuzhiyun {
54*4882a593Smuzhiyun 	hw_watchdog_reset();
55*4882a593Smuzhiyun }
56*4882a593Smuzhiyun 
hw_watchdog_init(void)57*4882a593Smuzhiyun void hw_watchdog_init(void)
58*4882a593Smuzhiyun {
59*4882a593Smuzhiyun 	int ret;
60*4882a593Smuzhiyun 
61*4882a593Smuzhiyun 	writel((XWT_CSR0_WRS_MASK | XWT_CSR0_WDS_MASK | XWT_CSR0_EWDT1_MASK),
62*4882a593Smuzhiyun 	       &watchdog_base->twcsr0);
63*4882a593Smuzhiyun 	writel(XWT_CSRX_EWDT2_MASK, &watchdog_base->twcsr1);
64*4882a593Smuzhiyun 
65*4882a593Smuzhiyun 	ret = install_interrupt_handler(CONFIG_WATCHDOG_IRQ,
66*4882a593Smuzhiyun 						hw_watchdog_isr, NULL);
67*4882a593Smuzhiyun 	if (ret)
68*4882a593Smuzhiyun 		puts("Watchdog IRQ registration failed.");
69*4882a593Smuzhiyun }
70