xref: /openbmc/u-boot/drivers/serial/serial_sh.c (revision c9aa831e)
1 /*
2  * SuperH SCIF device driver.
3  * Copyright (C) 2007,2008,2010 Nobuhiro Iwamatsu
4  * Copyright (C) 2002 - 2008  Paul Mundt
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  */
20 
21 #include <common.h>
22 #include <asm/io.h>
23 #include <asm/processor.h>
24 #include "serial_sh.h"
25 #include <serial.h>
26 #include <linux/compiler.h>
27 
28 #if defined(CONFIG_CONS_SCIF0)
29 # define SCIF_BASE	SCIF0_BASE
30 #elif defined(CONFIG_CONS_SCIF1)
31 # define SCIF_BASE	SCIF1_BASE
32 #elif defined(CONFIG_CONS_SCIF2)
33 # define SCIF_BASE	SCIF2_BASE
34 #elif defined(CONFIG_CONS_SCIF3)
35 # define SCIF_BASE	SCIF3_BASE
36 #elif defined(CONFIG_CONS_SCIF4)
37 # define SCIF_BASE	SCIF4_BASE
38 #elif defined(CONFIG_CONS_SCIF5)
39 # define SCIF_BASE	SCIF5_BASE
40 #elif defined(CONFIG_CONS_SCIF6)
41 # define SCIF_BASE	SCIF6_BASE
42 #elif defined(CONFIG_CONS_SCIF7)
43 # define SCIF_BASE	SCIF7_BASE
44 #else
45 # error "Default SCIF doesn't set....."
46 #endif
47 
48 #if defined(CONFIG_SCIF_A)
49 	#define SCIF_BASE_PORT	PORT_SCIFA
50 #else
51 	#define SCIF_BASE_PORT	PORT_SCIF
52 #endif
53 
54 static struct uart_port sh_sci = {
55 	.membase	= (unsigned char*)SCIF_BASE,
56 	.mapbase	= SCIF_BASE,
57 	.type		= SCIF_BASE_PORT,
58 };
59 
60 static void sh_serial_setbrg(void)
61 {
62 	DECLARE_GLOBAL_DATA_PTR;
63 	sci_out(&sh_sci, SCBRR, SCBRR_VALUE(gd->baudrate, CONFIG_SYS_CLK_FREQ));
64 }
65 
66 static int sh_serial_init(void)
67 {
68 	sci_out(&sh_sci, SCSCR , SCSCR_INIT(&sh_sci));
69 	sci_out(&sh_sci, SCSCR , SCSCR_INIT(&sh_sci));
70 	sci_out(&sh_sci, SCSMR, 0);
71 	sci_out(&sh_sci, SCSMR, 0);
72 	sci_out(&sh_sci, SCFCR, SCFCR_RFRST|SCFCR_TFRST);
73 	sci_in(&sh_sci, SCFCR);
74 	sci_out(&sh_sci, SCFCR, 0);
75 
76 	serial_setbrg();
77 	return 0;
78 }
79 
80 #if defined(CONFIG_CPU_SH7760) || \
81 	defined(CONFIG_CPU_SH7780) || \
82 	defined(CONFIG_CPU_SH7785) || \
83 	defined(CONFIG_CPU_SH7786)
84 static int scif_rxfill(struct uart_port *port)
85 {
86 	return sci_in(port, SCRFDR) & 0xff;
87 }
88 #elif defined(CONFIG_CPU_SH7763)
89 static int scif_rxfill(struct uart_port *port)
90 {
91 	if ((port->mapbase == 0xffe00000) ||
92 		(port->mapbase == 0xffe08000)) {
93 		/* SCIF0/1*/
94 		return sci_in(port, SCRFDR) & 0xff;
95 	} else {
96 		/* SCIF2 */
97 		return sci_in(port, SCFDR) & SCIF2_RFDC_MASK;
98 	}
99 }
100 #elif defined(CONFIG_ARCH_SH7372)
101 static int scif_rxfill(struct uart_port *port)
102 {
103 	if (port->type == PORT_SCIFA)
104 		return sci_in(port, SCFDR) & SCIF_RFDC_MASK;
105 	else
106 		return sci_in(port, SCRFDR);
107 }
108 #else
109 static int scif_rxfill(struct uart_port *port)
110 {
111 	return sci_in(port, SCFDR) & SCIF_RFDC_MASK;
112 }
113 #endif
114 
115 static int serial_rx_fifo_level(void)
116 {
117 	return scif_rxfill(&sh_sci);
118 }
119 
120 static void handle_error(void)
121 {
122 	sci_in(&sh_sci, SCxSR);
123 	sci_out(&sh_sci, SCxSR, SCxSR_ERROR_CLEAR(&sh_sci));
124 	sci_in(&sh_sci, SCLSR);
125 	sci_out(&sh_sci, SCLSR, 0x00);
126 }
127 
128 void serial_raw_putc(const char c)
129 {
130 	while (1) {
131 		/* Tx fifo is empty */
132 		if (sci_in(&sh_sci, SCxSR) & SCxSR_TEND(&sh_sci))
133 			break;
134 	}
135 
136 	sci_out(&sh_sci, SCxTDR, c);
137 	sci_out(&sh_sci, SCxSR, sci_in(&sh_sci, SCxSR) & ~SCxSR_TEND(&sh_sci));
138 }
139 
140 static void sh_serial_putc(const char c)
141 {
142 	if (c == '\n')
143 		serial_raw_putc('\r');
144 	serial_raw_putc(c);
145 }
146 
147 static int sh_serial_tstc(void)
148 {
149 	if (sci_in(&sh_sci, SCxSR) & SCIF_ERRORS) {
150 		handle_error();
151 		return 0;
152 	}
153 
154 	return serial_rx_fifo_level() ? 1 : 0;
155 }
156 
157 
158 int serial_getc_check(void)
159 {
160 	unsigned short status;
161 
162 	status = sci_in(&sh_sci, SCxSR);
163 
164 	if (status & SCIF_ERRORS)
165 		handle_error();
166 	if (sci_in(&sh_sci, SCLSR) & SCxSR_ORER(&sh_sci))
167 		handle_error();
168 	return status & (SCIF_DR | SCxSR_RDxF(&sh_sci));
169 }
170 
171 static int sh_serial_getc(void)
172 {
173 	unsigned short status;
174 	char ch;
175 
176 	while (!serial_getc_check())
177 		;
178 
179 	ch = sci_in(&sh_sci, SCxRDR);
180 	status = sci_in(&sh_sci, SCxSR);
181 
182 	sci_out(&sh_sci, SCxSR, SCxSR_RDxF_CLEAR(&sh_sci));
183 
184 	if (status & SCIF_ERRORS)
185 			handle_error();
186 
187 	if (sci_in(&sh_sci, SCLSR) & SCxSR_ORER(&sh_sci))
188 		handle_error();
189 	return ch;
190 }
191 
192 static struct serial_device sh_serial_drv = {
193 	.name	= "sh_serial",
194 	.start	= sh_serial_init,
195 	.stop	= NULL,
196 	.setbrg	= sh_serial_setbrg,
197 	.putc	= sh_serial_putc,
198 	.puts	= default_serial_puts,
199 	.getc	= sh_serial_getc,
200 	.tstc	= sh_serial_tstc,
201 };
202 
203 void sh_serial_initialize(void)
204 {
205 	serial_register(&sh_serial_drv);
206 }
207 
208 __weak struct serial_device *default_serial_console(void)
209 {
210 	return &sh_serial_drv;
211 }
212