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#include <part/fallback_boot.h>
/* Base Address */
#ifndef TTYS0_BASE
#define TTYS0_BASE 0x3f8
#endif
/* Baud Rate */
#ifndef TTYS0_BAUD
#define TTYS0_BAUD 115200
#endif
#if ((115200%TTYS0_BAUD) != 0)
#error Bad ttys0 baud rate
#endif
/* Baud Rate Divisor */
#define TTYS0_DIV (115200/TTYS0_BAUD)
#define TTYS0_DIV_LO (TTYS0_DIV&0xFF)
#define TTYS0_DIV_HI ((TTYS0_DIV >> 8)&0xFF)
/* Line Control Settings */
#ifndef TTYS0_LCS
/* Set 8bit, 1 stop bit, no parity */
#define TTYS0_LCS 0x3
#endif
/* Data */
#define TTYS0_RBR (TTYS0_BASE+0x00)
/* Control */
#define TTYS0_TBR TTYS0_RBR
#define TTYS0_IER (TTYS0_BASE+0x01)
#define TTYS0_IIR (TTYS0_BASE+0x02)
#define TTYS0_FCR TTYS0_IIR
#define TTYS0_LCR (TTYS0_BASE+0x03)
#define TTYS0_MCR (TTYS0_BASE+0x04)
#define TTYS0_DLL TTYS0_RBR
#define TTYS0_DLM TTYS0_IER
/* Status */
#define TTYS0_LSR (TTYS0_BASE+0x05)
#define TTYS0_MSR (TTYS0_BASE+0x06)
#define TTYS0_SCR (TTYS0_BASE+0x07)
#if USE_OPTION_TABLE == 1
.section ".rom.data"
.type div,@object
.size div,8
div:
.byte 1,2,3,6,12,24,48,96
.previous
#endif
jmp serial0
/* uses: ax, dx */
#define TTYS0_TX_AL \
mov %al, %ah ; \
9: mov $TTYS0_LSR, %dx ; \
inb %dx, %al ; \
test $0x20, %al ; \
je 9b ; \
mov $TTYS0_TBR, %dx ; \
mov %ah, %al ; \
outb %al, %dx
serial_init:
/* Set 115.2Kbps,8n1 */
/* Set 8bit, 1 stop bit, no parity, DLAB */
mov $TTYS0_LCR, %dx
mov $(TTYS0_LCS | 0x80), %al
out %al, %dx
/* set Baud Rate Divisor to 1 ==> 115200 Buad */
#if USE_OPTION_TABLE == 1
movb $(RTC_BOOT_BYTE+1), %al
outb %al, $0x70
xorl %edx,%edx
inb $0x71, %al
andb $7,%al
movb %al,%dl
movb div(%edx),%al
mov $TTYS0_DLL, %dx
out %al, %dx
mov $TTYS0_DLM, %dx
xorb %al,%al
out %al, %dx
#else
mov $TTYS0_DLL, %dx
mov $TTYS0_DIV_LO, %al
out %al, %dx
mov $TTYS0_DLM, %dx
mov $TTYS0_DIV_HI, %al
out %al, %dx
#endif
/* Disable DLAB */
mov $TTYS0_LCR, %dx
mov $(TTYS0_LCS & 0x7f), %al
out %al, %dx
RETSP
serial0:
CALLSP(serial_init)
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