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
serial_in(struct uart_8250_port * up,int offset)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
serial_out(struct uart_8250_port * up,int offset,int value)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
serial_dl_read(struct uart_8250_port * up)107 static inline int serial_dl_read(struct uart_8250_port *up)
108 {
109 return up->dl_read(up);
110 }
111
serial_dl_write(struct uart_8250_port * up,int value)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
serial8250_pnp_init(void)136 static inline int serial8250_pnp_init(void) { return 0; }
serial8250_pnp_exit(void)137 static inline void serial8250_pnp_exit(void) { }
138 #endif
139
140 #ifdef CONFIG_ARCH_OMAP1
is_omap1_8250(struct uart_8250_port * pt)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
is_omap1510_8250(struct uart_8250_port * pt)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
is_omap1_8250(struct uart_8250_port * pt)167 static inline int is_omap1_8250(struct uart_8250_port *pt)
168 {
169 return 0;
170 }
is_omap1510_8250(struct uart_8250_port * pt)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
serial8250_tx_dma(struct uart_8250_port * p)183 static inline int serial8250_tx_dma(struct uart_8250_port *p)
184 {
185 return -1;
186 }
serial8250_rx_dma(struct uart_8250_port * p,unsigned int iir)187 static inline int serial8250_rx_dma(struct uart_8250_port *p, unsigned int iir)
188 {
189 return -1;
190 }
serial8250_request_dma(struct uart_8250_port * p)191 static inline int serial8250_request_dma(struct uart_8250_port *p)
192 {
193 return -1;
194 }
serial8250_release_dma(struct uart_8250_port * p)195 static inline void serial8250_release_dma(struct uart_8250_port *p) { }
196 #endif
197
ns16550a_goto_highspeed(struct uart_8250_port * up)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
serial_index(struct uart_port * port)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