serial_16550.h

这个vivi的功能很丰富

#include <types.h>

/*
 * The type definitions.  These are from Ted Ts'o's serial.h
 */
#define PORT_UNKNOWN	0
#define PORT_8250	1
#define PORT_16450	2
#define PORT_16550	3
#define PORT_16550A	4
#define PORT_CIRRUS	5
#define PORT_16650	6
#define PORT_16650V2	7
#define PORT_16750	8
#define PORT_STARTECH	9
#define PORT_16C950	10
#define PORT_16654	11
#define PORT_16850	12
#define PORT_RSA	13
#define PORT_MAX_8250	13	/* max port ID */

#define SERIAL_IO_PORT	0
#define SERIAL_IO_HUB6	1
#define SERIAL_IO_MEM	2

struct serial_uart_config {
	char	*name;
	int	dfl_xmit_fifo_size;
	int	flags;
};

#define UART_CLEAR_FIFO		0x01
#define UART_USE_FIFO		0x02
#define UART_STARTECH		0x04

/*
 * Definitions for async_struct (and serial_struct) flags field
 */
#define ASYNC_HUP_NOTIFY 0x0001 /* Notify getty on hangups and closes 
				   on the callout port */
#define ASYNC_FOURPORT  0x0002	/* Set OU1, OUT2 per AST Fourport settings */
#define ASYNC_SAK	0x0004	/* Secure Attention Key (Orange book) */
#define ASYNC_SPLIT_TERMIOS 0x0008 /* Separate termios for dialin/callout */

#define ASYNC_SPD_MASK	0x1030
#define ASYNC_SPD_HI	0x0010	/* Use 56000 instead of 38400 bps */

#define ASYNC_SPD_VHI	0x0020  /* Use 115200 instead of 38400 bps */
#define ASYNC_SPD_CUST	0x0030  /* Use user-specified divisor */

#define ASYNC_SKIP_TEST	0x0040 /* Skip UART test during autoconfiguration */
#define ASYNC_AUTO_IRQ  0x0080 /* Do automatic IRQ during autoconfiguration */
#define ASYNC_SESSION_LOCKOUT 0x0100 /* Lock out cua opens based on session */
#define ASYNC_PGRP_LOCKOUT    0x0200 /* Lock out cua opens based on pgrp */
#define ASYNC_CALLOUT_NOHUP   0x0400 /* Don't do hangups for cua device */

#define ASYNC_HARDPPS_CD	0x0800	/* Call hardpps when CD goes high  */

#define ASYNC_SPD_SHI	0x1000	/* Use 230400 instead of 38400 bps */
#define ASYNC_SPD_WARP	0x1010	/* Use 460800 instead of 38400 bps */

#define ASYNC_LOW_LATENCY 0x2000 /* Request low latency behaviour */

#define ASYNC_BUGGY_UART  0x4000 /* This is a buggy UART, skip some safety
				  * checks.  Note: can be dangerous! */

#define ASYNC_AUTOPROBE	 0x8000 /* Port was autoprobed by PCI or PNP code */

#define ASYNC_FLAGS	0x7FFF	/* Possible legal async flags */
#define ASYNC_USR_MASK	0x3430	/* Legal flags that non-privileged
				 * users can set or reset */

/* Internal flags used only by kernel/chr_drv/serial.c */
#define ASYNC_INITIALIZED	0x80000000 /* Serial port was initialized */
#define ASYNC_CALLOUT_ACTIVE	0x40000000 /* Call out device is active */
#define ASYNC_NORMAL_ACTIVE	0x20000000 /* Normal device is active */
#define ASYNC_BOOT_AUTOCONF	0x10000000 /* Autoconfigure port on bootup */
#define ASYNC_CLOSING		0x08000000 /* Serial port is closing */
#define ASYNC_CTS_FLOW		0x04000000 /* Do CTS flow control */
#define ASYNC_CHECK_CD		0x02000000 /* i.e., CLOCAL */
#define ASYNC_SHARE_IRQ		0x01000000 /* for multifunction cards
					     --- no longer used */
#define ASYNC_CONS_FLOW		0x00800000 /* flow control for console  */

#define ASYNC_BOOT_ONLYMCA	0x00400000 /* Probe only if MCA bus */
#define ASYNC_INTERNAL_FLAGS	0xFFC00000 /* Internal flags */

struct uart_port {
	u_int			iobase;			/* in/out[bwl] */
	void			*membase;		/* read/write[bwl] */
	u_int			irq;
	u_int			uartclk;
	u_char			fifosize;		/* tx fifo size */
	u_char			x_char;
	u_char			regshift;		/* reg offset shift */
	u_char			iotype;			/* io access style */
	u_char			hub6;
	u_char			unused[7];
	u_int			read_status_mask;
	u_int			ignore_status_mask;
	u_int			flags;
	u_int			type;			/* port type */
	u_int			line;
};