xref: /openbmc/linux/drivers/tty/serial/8250/8250.h (revision 9cfc5c90)
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, unsigned int iir);
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 #define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8)
88 
89 #ifdef CONFIG_SERIAL_8250_SHARE_IRQ
90 #define SERIAL8250_SHARE_IRQS 1
91 #else
92 #define SERIAL8250_SHARE_IRQS 0
93 #endif
94 
95 static inline int serial_in(struct uart_8250_port *up, int offset)
96 {
97 	return up->port.serial_in(&up->port, offset);
98 }
99 
100 static inline void serial_out(struct uart_8250_port *up, int offset, int value)
101 {
102 	up->port.serial_out(&up->port, offset, value);
103 }
104 
105 void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p);
106 
107 static inline int serial_dl_read(struct uart_8250_port *up)
108 {
109 	return up->dl_read(up);
110 }
111 
112 static inline void serial_dl_write(struct uart_8250_port *up, int value)
113 {
114 	up->dl_write(up, value);
115 }
116 
117 struct uart_8250_port *serial8250_get_port(int line);
118 void serial8250_rpm_get(struct uart_8250_port *p);
119 void serial8250_rpm_put(struct uart_8250_port *p);
120 
121 #if defined(__alpha__) && !defined(CONFIG_PCI)
122 /*
123  * Digital did something really horribly wrong with the OUT1 and OUT2
124  * lines on at least some ALPHA's.  The failure mode is that if either
125  * is cleared, the machine locks up with endless interrupts.
126  */
127 #define ALPHA_KLUDGE_MCR  (UART_MCR_OUT2 | UART_MCR_OUT1)
128 #else
129 #define ALPHA_KLUDGE_MCR 0
130 #endif
131 
132 #ifdef CONFIG_SERIAL_8250_PNP
133 int serial8250_pnp_init(void);
134 void serial8250_pnp_exit(void);
135 #else
136 static inline int serial8250_pnp_init(void) { return 0; }
137 static inline void serial8250_pnp_exit(void) { }
138 #endif
139 
140 #ifdef CONFIG_ARCH_OMAP1
141 static inline int is_omap1_8250(struct uart_8250_port *pt)
142 {
143 	int res;
144 
145 	switch (pt->port.mapbase) {
146 	case OMAP1_UART1_BASE:
147 	case OMAP1_UART2_BASE:
148 	case OMAP1_UART3_BASE:
149 		res = 1;
150 		break;
151 	default:
152 		res = 0;
153 		break;
154 	}
155 
156 	return res;
157 }
158 
159 static inline int is_omap1510_8250(struct uart_8250_port *pt)
160 {
161 	if (!cpu_is_omap1510())
162 		return 0;
163 
164 	return is_omap1_8250(pt);
165 }
166 #else
167 static inline int is_omap1_8250(struct uart_8250_port *pt)
168 {
169 	return 0;
170 }
171 static inline int is_omap1510_8250(struct uart_8250_port *pt)
172 {
173 	return 0;
174 }
175 #endif
176 
177 #ifdef CONFIG_SERIAL_8250_DMA
178 extern int serial8250_tx_dma(struct uart_8250_port *);
179 extern int serial8250_rx_dma(struct uart_8250_port *, unsigned int iir);
180 extern int serial8250_request_dma(struct uart_8250_port *);
181 extern void serial8250_release_dma(struct uart_8250_port *);
182 #else
183 static inline int serial8250_tx_dma(struct uart_8250_port *p)
184 {
185 	return -1;
186 }
187 static inline int serial8250_rx_dma(struct uart_8250_port *p, unsigned int iir)
188 {
189 	return -1;
190 }
191 static inline int serial8250_request_dma(struct uart_8250_port *p)
192 {
193 	return -1;
194 }
195 static inline void serial8250_release_dma(struct uart_8250_port *p) { }
196 #endif
197 
198 static inline int ns16550a_goto_highspeed(struct uart_8250_port *up)
199 {
200 	unsigned char status;
201 
202 	status = serial_in(up, 0x04); /* EXCR2 */
203 #define PRESL(x) ((x) & 0x30)
204 	if (PRESL(status) == 0x10) {
205 		/* already in high speed mode */
206 		return 0;
207 	} else {
208 		status &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */
209 		status |= 0x10;  /* 1.625 divisor for baud_base --> 921600 */
210 		serial_out(up, 0x04, status);
211 	}
212 	return 1;
213 }
214 
215 static inline int serial_index(struct uart_port *port)
216 {
217 	return port->minor - 64;
218 }
219 
220 #if 0
221 #define DEBUG_INTR(fmt...)	printk(fmt)
222 #else
223 #define DEBUG_INTR(fmt...)	do { } while (0)
224 #endif
225