linux/arch/sh/include/cpu-sh2/cpu/watchdog.h

67 lines
1.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0
*
* include/asm-sh/cpu-sh2/watchdog.h
*
* Copyright (C) 2002, 2003 Paul Mundt
*/
#ifndef __ASM_CPU_SH2_WATCHDOG_H
#define __ASM_CPU_SH2_WATCHDOG_H
/*
* More SH-2 brilliance .. its not good enough that we can't read
* and write the same sizes to WTCNT, now we have to read and write
* with different sizes at different addresses for WTCNT _and_ RSTCSR.
*
* At least on the bright side no one has managed to screw over WTCSR
* in this fashion .. yet.
*/
/* Register definitions */
#define WTCNT 0xfffffe80
#define WTCSR 0xfffffe80
#define RSTCSR 0xfffffe82
#define WTCNT_R (WTCNT + 1)
#define RSTCSR_R (RSTCSR + 1)
/* Bit definitions */
#define WTCSR_IOVF 0x80
#define WTCSR_WT 0x40
#define WTCSR_TME 0x20
#define WTCSR_RSTS 0x00
#define RSTCSR_RSTS 0x20
/**
* sh_wdt_read_rstcsr - Read from Reset Control/Status Register
*
* Reads back the RSTCSR value.
*/
static inline __u8 sh_wdt_read_rstcsr(void)
{
/*
* Same read/write brain-damage as for WTCNT here..
*/
return __raw_readb(RSTCSR_R);
}
/**
* sh_wdt_write_csr - Write to Reset Control/Status Register
*
* @val: Value to write
*
* Writes the given value @val to the lower byte of the control/status
* register. The upper byte is set manually on each write.
*/
static inline void sh_wdt_write_rstcsr(__u8 val)
{
/*
* Note: Due to the brain-damaged nature of this register,
* we can't presently touch the WOVF bit, since the upper byte
* has to be swapped for this. So just leave it alone..
*/
__raw_writeb((WTCNT_HIGH << 8) | (__u16)val, RSTCSR);
}
#endif /* __ASM_CPU_SH2_WATCHDOG_H */