xref: /openbmc/linux/drivers/tty/serial/8250/8250.h (revision 78700c0a)
1 /*
2  *  Driver for 8250/16550-type serial ports
3  *
4  *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
5  *
6  *  Copyright (C) 2001 Russell King.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  */
13 
14 #include <linux/serial_8250.h>
15 #include <linux/serial_reg.h>
16 #include <linux/dmaengine.h>
17 
18 struct uart_8250_dma {
19 	int (*tx_dma)(struct uart_8250_port *p);
20 	int (*rx_dma)(struct uart_8250_port *p);
21 
22 	/* Filter function */
23 	dma_filter_fn		fn;
24 	/* Parameter to the filter function */
25 	void			*rx_param;
26 	void			*tx_param;
27 
28 	struct dma_slave_config	rxconf;
29 	struct dma_slave_config	txconf;
30 
31 	struct dma_chan		*rxchan;
32 	struct dma_chan		*txchan;
33 
34 	dma_addr_t		rx_addr;
35 	dma_addr_t		tx_addr;
36 
37 	dma_cookie_t		rx_cookie;
38 	dma_cookie_t		tx_cookie;
39 
40 	void			*rx_buf;
41 
42 	size_t			rx_size;
43 	size_t			tx_size;
44 
45 	unsigned char		tx_running;
46 	unsigned char		tx_err;
47 	unsigned char		rx_running;
48 };
49 
50 struct old_serial_port {
51 	unsigned int uart;
52 	unsigned int baud_base;
53 	unsigned int port;
54 	unsigned int irq;
55 	upf_t        flags;
56 	unsigned char hub6;
57 	unsigned char io_type;
58 	unsigned char __iomem *iomem_base;
59 	unsigned short iomem_reg_shift;
60 	unsigned long irqflags;
61 };
62 
63 struct serial8250_config {
64 	const char	*name;
65 	unsigned short	fifo_size;
66 	unsigned short	tx_loadsz;
67 	unsigned char	fcr;
68 	unsigned char	rxtrig_bytes[UART_FCR_R_TRIG_MAX_STATE];
69 	unsigned int	flags;
70 };
71 
72 #define UART_CAP_FIFO	(1 << 8)	/* UART has FIFO */
73 #define UART_CAP_EFR	(1 << 9)	/* UART has EFR */
74 #define UART_CAP_SLEEP	(1 << 10)	/* UART has IER sleep */
75 #define UART_CAP_AFE	(1 << 11)	/* MCR-based hw flow control */
76 #define UART_CAP_UUE	(1 << 12)	/* UART needs IER bit 6 set (Xscale) */
77 #define UART_CAP_RTOIE	(1 << 13)	/* UART needs IER bit 4 set (Xscale, Tegra) */
78 #define UART_CAP_HFIFO	(1 << 14)	/* UART has a "hidden" FIFO */
79 #define UART_CAP_RPM	(1 << 15)	/* Runtime PM is active while idle */
80 
81 #define UART_BUG_QUOT	(1 << 0)	/* UART has buggy quot LSB */
82 #define UART_BUG_TXEN	(1 << 1)	/* UART has buggy TX IIR status */
83 #define UART_BUG_NOMSR	(1 << 2)	/* UART has buggy MSR status bits (Au1x00) */
84 #define UART_BUG_THRE	(1 << 3)	/* UART has buggy THRE reassertion */
85 #define UART_BUG_PARITY	(1 << 4)	/* UART mishandles parity if FIFO enabled */
86 
87 
88 #ifdef CONFIG_SERIAL_8250_SHARE_IRQ
89 #define SERIAL8250_SHARE_IRQS 1
90 #else
91 #define SERIAL8250_SHARE_IRQS 0
92 #endif
93 
94 #define SERIAL8250_PORT_FLAGS(_base, _irq, _flags)		\
95 	{							\
96 		.iobase		= _base,			\
97 		.irq		= _irq,				\
98 		.uartclk	= 1843200,			\
99 		.iotype		= UPIO_PORT,			\
100 		.flags		= UPF_BOOT_AUTOCONF | (_flags),	\
101 	}
102 
103 #define SERIAL8250_PORT(_base, _irq) SERIAL8250_PORT_FLAGS(_base, _irq, 0)
104 
105 
106 static inline int serial_in(struct uart_8250_port *up, int offset)
107 {
108 	return up->port.serial_in(&up->port, offset);
109 }
110 
111 static inline void serial_out(struct uart_8250_port *up, int offset, int value)
112 {
113 	up->port.serial_out(&up->port, offset, value);
114 }
115 
116 void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p);
117 
118 static inline int serial_dl_read(struct uart_8250_port *up)
119 {
120 	return up->dl_read(up);
121 }
122 
123 static inline void serial_dl_write(struct uart_8250_port *up, int value)
124 {
125 	up->dl_write(up, value);
126 }
127 
128 struct uart_8250_port *serial8250_get_port(int line);
129 void serial8250_rpm_get(struct uart_8250_port *p);
130 void serial8250_rpm_put(struct uart_8250_port *p);
131 int serial8250_em485_init(struct uart_8250_port *p);
132 void serial8250_em485_destroy(struct uart_8250_port *p);
133 
134 #if defined(__alpha__) && !defined(CONFIG_PCI)
135 /*
136  * Digital did something really horribly wrong with the OUT1 and OUT2
137  * lines on at least some ALPHA's.  The failure mode is that if either
138  * is cleared, the machine locks up with endless interrupts.
139  */
140 #define ALPHA_KLUDGE_MCR  (UART_MCR_OUT2 | UART_MCR_OUT1)
141 #else
142 #define ALPHA_KLUDGE_MCR 0
143 #endif
144 
145 #ifdef CONFIG_SERIAL_8250_PNP
146 int serial8250_pnp_init(void);
147 void serial8250_pnp_exit(void);
148 #else
149 static inline int serial8250_pnp_init(void) { return 0; }
150 static inline void serial8250_pnp_exit(void) { }
151 #endif
152 
153 #ifdef CONFIG_SERIAL_8250_FINTEK
154 int fintek_8250_probe(struct uart_8250_port *uart);
155 #else
156 static inline int fintek_8250_probe(struct uart_8250_port *uart) { return 0; }
157 #endif
158 
159 #ifdef CONFIG_ARCH_OMAP1
160 static inline int is_omap1_8250(struct uart_8250_port *pt)
161 {
162 	int res;
163 
164 	switch (pt->port.mapbase) {
165 	case OMAP1_UART1_BASE:
166 	case OMAP1_UART2_BASE:
167 	case OMAP1_UART3_BASE:
168 		res = 1;
169 		break;
170 	default:
171 		res = 0;
172 		break;
173 	}
174 
175 	return res;
176 }
177 
178 static inline int is_omap1510_8250(struct uart_8250_port *pt)
179 {
180 	if (!cpu_is_omap1510())
181 		return 0;
182 
183 	return is_omap1_8250(pt);
184 }
185 #else
186 static inline int is_omap1_8250(struct uart_8250_port *pt)
187 {
188 	return 0;
189 }
190 static inline int is_omap1510_8250(struct uart_8250_port *pt)
191 {
192 	return 0;
193 }
194 #endif
195 
196 #ifdef CONFIG_SERIAL_8250_DMA
197 extern int serial8250_tx_dma(struct uart_8250_port *);
198 extern int serial8250_rx_dma(struct uart_8250_port *);
199 extern void serial8250_rx_dma_flush(struct uart_8250_port *);
200 extern int serial8250_request_dma(struct uart_8250_port *);
201 extern void serial8250_release_dma(struct uart_8250_port *);
202 #else
203 static inline int serial8250_tx_dma(struct uart_8250_port *p)
204 {
205 	return -1;
206 }
207 static inline int serial8250_rx_dma(struct uart_8250_port *p)
208 {
209 	return -1;
210 }
211 static inline void serial8250_rx_dma_flush(struct uart_8250_port *p) { }
212 static inline int serial8250_request_dma(struct uart_8250_port *p)
213 {
214 	return -1;
215 }
216 static inline void serial8250_release_dma(struct uart_8250_port *p) { }
217 #endif
218 
219 static inline int ns16550a_goto_highspeed(struct uart_8250_port *up)
220 {
221 	unsigned char status;
222 
223 	status = serial_in(up, 0x04); /* EXCR2 */
224 #define PRESL(x) ((x) & 0x30)
225 	if (PRESL(status) == 0x10) {
226 		/* already in high speed mode */
227 		return 0;
228 	} else {
229 		status &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */
230 		status |= 0x10;  /* 1.625 divisor for baud_base --> 921600 */
231 		serial_out(up, 0x04, status);
232 	}
233 	return 1;
234 }
235 
236 static inline int serial_index(struct uart_port *port)
237 {
238 	return port->minor - 64;
239 }
240 
241 #if 0
242 #define DEBUG_INTR(fmt...)	printk(fmt)
243 #else
244 #define DEBUG_INTR(fmt...)	do { } while (0)
245 #endif
246