1 /* 68328serial.h: Definitions for the mc68328 serial driver.
2  *
3  * Copyright (C) 1995       David S. Miller    <davem@caip.rutgers.edu>
4  * Copyright (C) 1998       Kenneth Albanowski <kjahds@kjahds.com>
5  * Copyright (C) 1998, 1999 D. Jeff Dionne     <jeff@uclinux.org>
6  * Copyright (C) 1999       Vladimir Gurevich  <vgurevic@cisco.com>
7  *
8  * VZ Support/Fixes             Evan Stawnyczy <e@lineo.ca>
9  */
10 
11 #ifndef _MC683XX_SERIAL_H
12 #define _MC683XX_SERIAL_H
13 
14 
15 struct serial_struct {
16 	int	type;
17 	int	line;
18 	int	port;
19 	int	irq;
20 	int	flags;
21 	int	xmit_fifo_size;
22 	int	custom_divisor;
23 	int	baud_base;
24 	unsigned short	close_delay;
25 	char	reserved_char[2];
26 	int	hub6;  /* FIXME: We don't have AT&T Hub6 boards! */
27 	unsigned short	closing_wait; /* time to wait before closing */
28 	unsigned short	closing_wait2; /* no longer used... */
29 	int	reserved[4];
30 };
31 
32 /*
33  * For the close wait times, 0 means wait forever for serial port to
34  * flush its output.  65535 means don't wait at all.
35  */
36 #define S_CLOSING_WAIT_INF	0
37 #define S_CLOSING_WAIT_NONE	65535
38 
39 /*
40  * Definitions for S_struct (and serial_struct) flags field
41  */
42 #define S_HUP_NOTIFY 0x0001 /* Notify getty on hangups and closes
43 				   on the callout port */
44 #define S_FOURPORT  0x0002	/* Set OU1, OUT2 per AST Fourport settings */
45 #define S_SAK	0x0004	/* Secure Attention Key (Orange book) */
46 #define S_SPLIT_TERMIOS 0x0008 /* Separate termios for dialin/callout */
47 
48 #define S_SPD_MASK	0x0030
49 #define S_SPD_HI	0x0010	/* Use 56000 instead of 38400 bps */
50 
51 #define S_SPD_VHI	0x0020  /* Use 115200 instead of 38400 bps */
52 #define S_SPD_CUST	0x0030  /* Use user-specified divisor */
53 
54 #define S_SKIP_TEST	0x0040 /* Skip UART test during autoconfiguration */
55 #define S_AUTO_IRQ  0x0080 /* Do automatic IRQ during autoconfiguration */
56 #define S_SESSION_LOCKOUT 0x0100 /* Lock out cua opens based on session */
57 #define S_PGRP_LOCKOUT    0x0200 /* Lock out cua opens based on pgrp */
58 #define S_CALLOUT_NOHUP   0x0400 /* Don't do hangups for cua device */
59 
60 #define S_FLAGS	0x0FFF	/* Possible legal S flags */
61 #define S_USR_MASK 0x0430	/* Legal flags that non-privileged
62 				 * users can set or reset */
63 
64 /* Internal flags used only by kernel/chr_drv/serial.c */
65 #define S_INITIALIZED	0x80000000 /* Serial port was initialized */
66 #define S_CALLOUT_ACTIVE	0x40000000 /* Call out device is active */
67 #define S_NORMAL_ACTIVE	0x20000000 /* Normal device is active */
68 #define S_BOOT_AUTOCONF	0x10000000 /* Autoconfigure port on bootup */
69 #define S_CLOSING		0x08000000 /* Serial port is closing */
70 #define S_CTS_FLOW		0x04000000 /* Do CTS flow control */
71 #define S_CHECK_CD		0x02000000 /* i.e., CLOCAL */
72 
73 /* Software state per channel */
74 
75 #ifdef __KERNEL__
76 
77 /*
78  * I believe this is the optimal setting that reduces the number of interrupts.
79  * At high speeds the output might become a little "bursted" (use USTCNT_TXHE
80  * if that bothers you), but in most cases it will not, since we try to
81  * transmit characters every time rs_interrupt is called. Thus, quite often
82  * you'll see that a receive interrupt occures before the transmit one.
83  *                                  -- Vladimir Gurevich
84  */
85 #define USTCNT_TX_INTR_MASK (USTCNT_TXEE)
86 
87 /*
88  * 68328 and 68EZ328 UARTS are a little bit different. EZ328 has special
89  * "Old data interrupt" which occures whenever the data stay in the FIFO
90  * longer than 30 bits time. This allows us to use FIFO without compromising
91  * latency. '328 does not have this feature and without the real  328-based
92  * board I would assume that RXRE is the safest setting.
93  *
94  * For EZ328 I use RXHE (Half empty) interrupt to reduce the number of
95  * interrupts. RXFE (receive queue full) causes the system to lose data
96  * at least at 115200 baud
97  *
98  * If your board is busy doing other stuff, you might consider to use
99  * RXRE (data ready intrrupt) instead.
100  *
101  * The other option is to make these INTR masks run-time configurable, so
102  * that people can dynamically adapt them according to the current usage.
103  *                                  -- Vladimir Gurevich
104  */
105 
106 /* (es) */
107 #if defined(CONFIG_M68EZ328) || defined(CONFIG_M68VZ328)
108 #define USTCNT_RX_INTR_MASK (USTCNT_RXHE | USTCNT_ODEN)
109 #elif defined(CONFIG_M68328)
110 #define USTCNT_RX_INTR_MASK (USTCNT_RXRE)
111 #else
112 #error Please, define the Rx interrupt events for your CPU
113 #endif
114 /* (/es) */
115 
116 /*
117  * This is our internal structure for each serial port's state.
118  *
119  * Many fields are paralleled by the structure used by the serial_struct
120  * structure.
121  *
122  * For definitions of the flags field, see tty.h
123  */
124 
125 struct m68k_serial {
126 	char soft_carrier;  /* Use soft carrier on this channel */
127 	char break_abort;   /* Is serial console in, so process brk/abrt */
128 	char is_cons;       /* Is this our console. */
129 
130 	/* We need to know the current clock divisor
131 	 * to read the bps rate the chip has currently
132 	 * loaded.
133 	 */
134 	unsigned char clk_divisor;  /* May be 1, 16, 32, or 64 */
135 	int baud;
136 	int			magic;
137 	int			baud_base;
138 	int			port;
139 	int			irq;
140 	int			flags; 		/* defined in tty.h */
141 	int			type; 		/* UART type */
142 	struct tty_struct 	*tty;
143 	int			read_status_mask;
144 	int			ignore_status_mask;
145 	int			timeout;
146 	int			xmit_fifo_size;
147 	int			custom_divisor;
148 	int			x_char;	/* xon/xoff character */
149 	int			close_delay;
150 	unsigned short		closing_wait;
151 	unsigned short		closing_wait2;
152 	unsigned long		event;
153 	unsigned long		last_active;
154 	int			line;
155 	int			count;	    /* # of fd on device */
156 	int			blocked_open; /* # of blocked opens */
157 	unsigned char 		*xmit_buf;
158 	int			xmit_head;
159 	int			xmit_tail;
160 	int			xmit_cnt;
161 	wait_queue_head_t	open_wait;
162 	wait_queue_head_t	close_wait;
163 };
164 
165 
166 #define SERIAL_MAGIC 0x5301
167 
168 /*
169  * The size of the serial xmit buffer is 1 page, or 4096 bytes
170  */
171 #define SERIAL_XMIT_SIZE 4096
172 
173 /*
174  * Events are used to schedule things to happen at timer-interrupt
175  * time, instead of at rs interrupt time.
176  */
177 #define RS_EVENT_WRITE_WAKEUP	0
178 
179 /*
180  * Define the number of ports supported and their irqs.
181  */
182 #define NR_PORTS 1
183 #define UART_IRQ_DEFNS {UART_IRQ_NUM}
184 
185 #endif /* __KERNEL__ */
186 #endif /* !(_MC683XX_SERIAL_H) */
187