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/*
* Architecture dependent definitions
* for NEC uPD4990A serial I/O real-time clock.
*
* Copyright 2001 TAKAI Kousuke <tak@kmc.kyoto-u.ac.jp>
* Kyoto University Microcomputer Club (KMC).
*
* References:
* uPD4990A serial I/O real-time clock users' manual (Japanese)
* No. S12828JJ4V0UM00 (4th revision), NEC Corporation, 1999.
*/
#ifndef _ASM_I386_uPD4990A_H
#define _ASM_I386_uPD4990A_H
#include <asm/io.h>
#define UPD4990A_IO (0x0020)
#define UPD4990A_IO_DATAOUT (0x0033)
#define UPD4990A_OUTPUT_DATA_CLK(data, clk) \
outb((((data) & 1) << 5) | (((clk) & 1) << 4) \
| UPD4990A_PAR_SERIAL_MODE, UPD4990A_IO)
#define UPD4990A_OUTPUT_CLK(clk) UPD4990A_OUTPUT_DATA_CLK(0, (clk))
#define UPD4990A_OUTPUT_STROBE(stb) \
outb(((stb) << 3) | UPD4990A_PAR_SERIAL_MODE, UPD4990A_IO)
/*
* Note: udelay() is *not* usable for UPD4990A_DELAY because
* the Linux kernel reads uPD4990A to set up system clock
* before calibrating delay...
*/
#define UPD4990A_DELAY(usec) \
do { \
if (__builtin_constant_p((usec)) && (usec) < 5) \
__asm__ (".rept %c1\n\toutb %%al,%0\n\t.endr" \
: : "N" (0x5F), \
"i" (((usec) * 10 + 5) / 6)); \
else { \
int _count = ((usec) * 10 + 5) / 6; \
__asm__ volatile ("1: outb %%al,%1\n\tloop 1b" \
: "=c" (_count) \
: "N" (0x5F), "0" (_count)); \
} \
} while (0)
/* Caller should ignore all bits except bit0 */
#define UPD4990A_READ_DATA() inb(UPD4990A_IO_DATAOUT)
#endif