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/*
* Low level serial I/O routines.
*/
#include <asm/asm.h>
#include <linux/errno.h>
#include <asm/current.h>
#include <asm/mipsregs.h>
#include <asm/regdef.h>
#include <asm/stackframe.h>
#include <asm/isadep.h>
#include <asm/unistd.h>
#define SERIAL_BASE 0xbd000020
#define SERB_DLABLO 0
#define SERB_DLABHI 1
#define SERB_FIFO 2
#define SERB_DATA 0
#define SERB_LCR 3
#define SERB_MCR 4
#define SERB_CMD 5
#define SERA_DLABLO 0x08
#define SERA_DLABHI 0x09
#define SERA_DATA 0x08
#define SERA_LCR 0x0B
#define SERA_MCR 0x0C
#define SERA_CMD 0x0D
#define TX_BUSY 0x20
/*
* To calculate divisor for different baud rates:
* divisor = 3686400/(baud rate x 16), where 3686400 is our
* 3.6864MHz clock input.
*/
/*
* routine to initialize the serial DUART. Channel A only
*/
.set noreorder
.global init_serial
.ent init_serial
init_serial:
li a0,SERIAL_BASE
#if 0
# init channel A
li t0,0x0083
sb t0,SERA_LCR(a0) # set DLAB
# li t0,24 # 9600 baud
li t0,2 # 115200 baud
sb t0,SERA_DLABLO(a0) # set divisor
li t0,0
sb t0,SERA_DLABHI(a0)
li t0,0x0003 # 8 data bits
sb t0,SERA_LCR(a0)
#endif
#if 1
# init channel B
li t0,0x0083
sb t0,SERB_LCR(a0) # set DLAB
li t0,24
sb t0,SERB_DLABLO(a0) # set divisor for 115200 baud
li t0,0
sb t0,SERB_DLABHI(a0)
li t0,0x0003 # 8 data bits
sb t0,SERB_LCR(a0)
li t0,0 # no fifo
sb t0,SERB_FIFO(a0)
#endif
li a0, 0xB4000000
li t0, 0x002fffff
sw t0, 0x464(a0)
jr ra
nop
.size init_serial, . - init_serial;
.end init_serial
.set reorder
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