1 /*
2 * arch/sh/kernel/early_printk.c
3 *
4 * Copyright (C) 1999, 2000 Niibe Yutaka
5 * Copyright (C) 2002 M. R. Brown
6 * Copyright (C) 2004 - 2007 Paul Mundt
7 *
8 * This file is subject to the terms and conditions of the GNU General Public
9 * License. See the file "COPYING" in the main directory of this archive
10 * for more details.
11 */
12 #include <linux/console.h>
13 #include <linux/tty.h>
14 #include <linux/init.h>
15 #include <linux/io.h>
16 #include <linux/delay.h>
17
18 #ifdef CONFIG_SH_STANDARD_BIOS
19 #include <asm/sh_bios.h>
20
21 /*
22 * Print a string through the BIOS
23 */
sh_console_write(struct console * co,const char * s,unsigned count)24 static void sh_console_write(struct console *co, const char *s,
25 unsigned count)
26 {
27 sh_bios_console_write(s, count);
28 }
29
30 /*
31 * Setup initial baud/bits/parity. We do two things here:
32 * - construct a cflag setting for the first rs_open()
33 * - initialize the serial port
34 * Return non-zero if we didn't find a serial port.
35 */
sh_console_setup(struct console * co,char * options)36 static int __init sh_console_setup(struct console *co, char *options)
37 {
38 int cflag = CREAD | HUPCL | CLOCAL;
39
40 /*
41 * Now construct a cflag setting.
42 * TODO: this is a totally bogus cflag, as we have
43 * no idea what serial settings the BIOS is using, or
44 * even if its using the serial port at all.
45 */
46 cflag |= B115200 | CS8 | /*no parity*/0;
47
48 co->cflag = cflag;
49
50 return 0;
51 }
52
53 static struct console bios_console = {
54 .name = "bios",
55 .write = sh_console_write,
56 .setup = sh_console_setup,
57 .flags = CON_PRINTBUFFER,
58 .index = -1,
59 };
60 #endif
61
62 #ifdef CONFIG_EARLY_SCIF_CONSOLE
63 #include <linux/serial_core.h>
64 #include "../../../drivers/serial/sh-sci.h"
65
66 #if defined(CONFIG_CPU_SUBTYPE_SH7720) || \
67 defined(CONFIG_CPU_SUBTYPE_SH7721)
68 #define EPK_SCSMR_VALUE 0x000
69 #define EPK_SCBRR_VALUE 0x00C
70 #define EPK_FIFO_SIZE 64
71 #define EPK_FIFO_BITS (0x7f00 >> 8)
72 #else
73 #define EPK_FIFO_SIZE 16
74 #define EPK_FIFO_BITS (0x1f00 >> 8)
75 #endif
76
77 static struct uart_port scif_port = {
78 .type = PORT_SCIF,
79 .mapbase = CONFIG_EARLY_SCIF_CONSOLE_PORT,
80 .membase = (char __iomem *)CONFIG_EARLY_SCIF_CONSOLE_PORT,
81 };
82
scif_sercon_putc(int c)83 static void scif_sercon_putc(int c)
84 {
85 while (((sci_in(&scif_port, SCFDR) & EPK_FIFO_BITS) >= EPK_FIFO_SIZE))
86 ;
87
88 sci_in(&scif_port, SCxSR);
89 sci_out(&scif_port, SCxSR, 0xf3 & ~(0x20 | 0x40));
90 sci_out(&scif_port, SCxTDR, c);
91
92 while ((sci_in(&scif_port, SCxSR) & 0x40) == 0)
93 ;
94
95 if (c == '\n')
96 scif_sercon_putc('\r');
97 }
98
scif_sercon_write(struct console * con,const char * s,unsigned count)99 static void scif_sercon_write(struct console *con, const char *s,
100 unsigned count)
101 {
102 while (count-- > 0)
103 scif_sercon_putc(*s++);
104 }
105
scif_sercon_setup(struct console * con,char * options)106 static int __init scif_sercon_setup(struct console *con, char *options)
107 {
108 con->cflag = CREAD | HUPCL | CLOCAL | B115200 | CS8;
109
110 return 0;
111 }
112
113 static struct console scif_console = {
114 .name = "sercon",
115 .write = scif_sercon_write,
116 .setup = scif_sercon_setup,
117 .flags = CON_PRINTBUFFER,
118 .index = -1,
119 };
120
121 #if !defined(CONFIG_SH_STANDARD_BIOS)
122 #if defined(CONFIG_CPU_SUBTYPE_SH7720) || \
123 defined(CONFIG_CPU_SUBTYPE_SH7721)
scif_sercon_init(char * s)124 static void scif_sercon_init(char *s)
125 {
126 sci_out(&scif_port, SCSCR, 0x0000); /* clear TE and RE */
127 sci_out(&scif_port, SCFCR, 0x4006); /* reset */
128 sci_out(&scif_port, SCSCR, 0x0000); /* select internal clock */
129 sci_out(&scif_port, SCSMR, EPK_SCSMR_VALUE);
130 sci_out(&scif_port, SCBRR, EPK_SCBRR_VALUE);
131
132 mdelay(1); /* wait 1-bit time */
133
134 sci_out(&scif_port, SCFCR, 0x0030); /* TTRG=b'11 */
135 sci_out(&scif_port, SCSCR, 0x0030); /* TE, RE */
136 }
137 #elif defined(CONFIG_CPU_SH4)
138 #define DEFAULT_BAUD 115200
139 /*
140 * Simple SCIF init, primarily aimed at SH7750 and other similar SH-4
141 * devices that aren't using sh-ipl+g.
142 */
scif_sercon_init(char * s)143 static void scif_sercon_init(char *s)
144 {
145 struct uart_port *port = &scif_port;
146 unsigned baud = DEFAULT_BAUD;
147 unsigned int status;
148 char *e;
149
150 if (*s == ',')
151 ++s;
152
153 if (*s) {
154 /* ignore ioport/device name */
155 s += strcspn(s, ",");
156 if (*s == ',')
157 s++;
158 }
159
160 if (*s) {
161 baud = simple_strtoul(s, &e, 0);
162 if (baud == 0 || s == e)
163 baud = DEFAULT_BAUD;
164 }
165
166 do {
167 status = sci_in(port, SCxSR);
168 } while (!(status & SCxSR_TEND(port)));
169
170 sci_out(port, SCSCR, 0); /* TE=0, RE=0 */
171 sci_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
172 sci_out(port, SCSMR, 0);
173
174 /* Set baud rate */
175 sci_out(port, SCBRR, (CONFIG_SH_PCLK_FREQ + 16 * baud) /
176 (32 * baud) - 1);
177 udelay((1000000+(baud-1)) / baud); /* Wait one bit interval */
178
179 sci_out(port, SCSPTR, 0);
180 sci_out(port, SCxSR, 0x60);
181 sci_out(port, SCLSR, 0);
182
183 sci_out(port, SCFCR, 0);
184 sci_out(port, SCSCR, 0x30); /* TE=1, RE=1 */
185 }
186 #endif /* defined(CONFIG_CPU_SUBTYPE_SH7720) */
187 #endif /* !defined(CONFIG_SH_STANDARD_BIOS) */
188 #endif /* CONFIG_EARLY_SCIF_CONSOLE */
189
190 /*
191 * Setup a default console, if more than one is compiled in, rely on the
192 * earlyprintk= parsing to give priority.
193 */
194 static struct console *early_console =
195 #ifdef CONFIG_SH_STANDARD_BIOS
196 &bios_console
197 #elif defined(CONFIG_EARLY_SCIF_CONSOLE)
198 &scif_console
199 #else
200 NULL
201 #endif
202 ;
203
setup_early_printk(char * buf)204 static int __init setup_early_printk(char *buf)
205 {
206 int keep_early = 0;
207
208 if (!buf)
209 return 0;
210
211 if (strstr(buf, "keep"))
212 keep_early = 1;
213
214 #ifdef CONFIG_SH_STANDARD_BIOS
215 if (!strncmp(buf, "bios", 4))
216 early_console = &bios_console;
217 #endif
218 #if defined(CONFIG_EARLY_SCIF_CONSOLE)
219 if (!strncmp(buf, "serial", 6)) {
220 early_console = &scif_console;
221
222 #if !defined(CONFIG_SH_STANDARD_BIOS)
223 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_CPU_SUBTYPE_SH7720) || \
224 defined(CONFIG_CPU_SUBTYPE_SH7721)
225 scif_sercon_init(buf + 6);
226 #endif
227 #endif
228 }
229 #endif
230
231 if (likely(early_console)) {
232 if (keep_early)
233 early_console->flags &= ~CON_BOOT;
234 else
235 early_console->flags |= CON_BOOT;
236 register_console(early_console);
237 }
238
239 return 0;
240 }
241 early_param("earlyprintk", setup_early_printk);
242