xref: /openbmc/u-boot/drivers/serial/serial_sh.c (revision 9973e3c6)
1 /*
2  * SuperH SCIF device driver.
3  * Copyright (c) 2007,2008 Nobuhiro Iwamatsu
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18  */
19 
20 #include <common.h>
21 #include <asm/processor.h>
22 
23 #ifdef CFG_SCIF_CONSOLE
24 
25 #if defined (CONFIG_CONS_SCIF0)
26 #define SCIF_BASE	SCIF0_BASE
27 #elif defined (CONFIG_CONS_SCIF1)
28 #define SCIF_BASE	SCIF1_BASE
29 #elif defined (CONFIG_CONS_SCIF2)
30 #define SCIF_BASE	SCIF2_BASE
31 #else
32 #error "Default SCIF doesn't set....."
33 #endif
34 
35 /* Base register */
36 #define SCSMR	(vu_short *)(SCIF_BASE + 0x0)
37 #define SCBRR	(vu_char  *)(SCIF_BASE + 0x4)
38 #define SCSCR	(vu_short *)(SCIF_BASE + 0x8)
39 #define SCFCR	(vu_short *)(SCIF_BASE + 0x18)
40 #define SCFDR	(vu_short *)(SCIF_BASE + 0x1C)
41 #ifdef CONFIG_CPU_SH7720	/* SH7720 specific */
42 # define SCFSR	(vu_short *)(SCIF_BASE + 0x14)	/* SCSSR */
43 # define SCFTDR	(vu_char  *)(SCIF_BASE + 0x20)
44 # define SCFRDR	(vu_char  *)(SCIF_BASE + 0x24)
45 #else
46 # define SCFTDR (vu_char  *)(SCIF_BASE + 0xC)
47 # define SCFSR 	(vu_short *)(SCIF_BASE + 0x10)
48 # define SCFRDR (vu_char  *)(SCIF_BASE + 0x14)
49 #endif
50 
51 #if	defined(CONFIG_CPU_SH7780) || \
52 	defined(CONFIG_CPU_SH7785)
53 # define SCRFDR	(vu_short *)(SCIF_BASE + 0x20)
54 # define SCSPTR	(vu_short *)(SCIF_BASE + 0x24)
55 # define SCLSR	(vu_short *)(SCIF_BASE + 0x28)
56 # define SCRER	(vu_short *)(SCIF_BASE + 0x2C)
57 # define LSR_ORER	1
58 # define FIFOLEVEL_MASK	0xFF
59 #elif defined(CONFIG_CPU_SH7763)
60 # if defined (CONFIG_CONS_SCIF2)
61 # define SCSPTR	(vu_short *)(SCIF_BASE + 0x20)
62 # define SCLSR 	(vu_short *)(SCIF_BASE + 0x24)
63 # define LSR_ORER	1
64 # define FIFOLEVEL_MASK	0x1F
65 # else
66 # define SCRFDR	(vu_short *)(SCIF_BASE + 0x20)
67 # define SCSPTR	(vu_short *)(SCIF_BASE + 0x24)
68 # define SCLSR	(vu_short *)(SCIF_BASE + 0x28)
69 # define SCRER	(vu_short *)(SCIF_BASE + 0x2C)
70 # define LSR_ORER	1
71 # define FIFOLEVEL_MASK	0xFF
72 # endif
73 #elif defined(CONFIG_CPU_SH7750) || \
74 	defined(CONFIG_CPU_SH7751) || \
75 	defined(CONFIG_CPU_SH7722)
76 # define SCSPTR	(vu_short *)(SCIF_BASE + 0x20)
77 # define SCLSR 	(vu_short *)(SCIF_BASE + 0x24)
78 # define LSR_ORER	1
79 # define FIFOLEVEL_MASK	0x1F
80 #elif defined(CONFIG_CPU_SH7720)
81 # define SCLSR		(vu_short *)(SCIF_BASE + 0x24)
82 # define LSR_ORER	0x0200
83 # define FIFOLEVEL_MASK	0x1F
84 #elif defined(CONFIG_CPU_SH7710) || \
85 	defined(CONFIG_CPU_SH7712)
86 # define SCLSR	SCFSR		/* SCSSR */
87 # define LSR_ORER	1
88 # define FIFOLEVEL_MASK	0x1F
89 #endif
90 
91 /* SCBRR register value setting */
92 #if defined(CONFIG_CPU_SH7720)
93 # define SCBRR_VALUE(bps, clk) (((clk*2)+16*bps)/(32*bps)-1)
94 #else /* Generic SuperH */
95 # define SCBRR_VALUE(bps, clk) ((clk+16*bps)/(32*bps)-1)
96 #endif
97 
98 #define SCR_RE 		(1 << 4)
99 #define SCR_TE 		(1 << 5)
100 #define FCR_RFRST	(1 << 1)	/* RFCL */
101 #define FCR_TFRST	(1 << 2)	/* TFCL */
102 #define FSR_DR   	(1 << 0)
103 #define FSR_RDF  	(1 << 1)
104 #define FSR_FER  	(1 << 3)
105 #define FSR_BRK  	(1 << 4)
106 #define FSR_FER  	(1 << 3)
107 #define FSR_TEND 	(1 << 6)
108 #define FSR_ER   	(1 << 7)
109 
110 /*----------------------------------------------------------------------*/
111 
112 void serial_setbrg(void)
113 {
114 	DECLARE_GLOBAL_DATA_PTR;
115 	*SCBRR = SCBRR_VALUE(gd->baudrate, CONFIG_SYS_CLK_FREQ);
116 }
117 
118 int serial_init(void)
119 {
120 	*SCSCR = (SCR_RE | SCR_TE);
121 	*SCSMR = 0;
122 	*SCSMR = 0;
123 	*SCFCR = (FCR_RFRST | FCR_TFRST);
124 	*SCFCR;
125 	*SCFCR = 0;
126 
127 	serial_setbrg();
128 	return 0;
129 }
130 
131 static int serial_rx_fifo_level(void)
132 {
133 #if defined(SCRFDR)
134 	return (*SCRFDR >> 0) & FIFOLEVEL_MASK;
135 #else
136 	return (*SCFDR >> 0) & FIFOLEVEL_MASK;
137 #endif
138 }
139 
140 void serial_raw_putc(const char c)
141 {
142 	unsigned int fsr_bits_to_clear;
143 
144 	while (1) {
145 		if (*SCFSR & FSR_TEND) {	/* Tx fifo is empty */
146 			fsr_bits_to_clear = FSR_TEND;
147 			break;
148 		}
149 	}
150 
151 	*SCFTDR = c;
152 	if (fsr_bits_to_clear != 0)
153 		*SCFSR &= ~fsr_bits_to_clear;
154 }
155 
156 void serial_putc(const char c)
157 {
158 	if (c == '\n')
159 		serial_raw_putc('\r');
160 	serial_raw_putc(c);
161 }
162 
163 void serial_puts(const char *s)
164 {
165 	char c;
166 	while ((c = *s++) != 0)
167 		serial_putc(c);
168 }
169 
170 int serial_tstc(void)
171 {
172 	return serial_rx_fifo_level()? 1 : 0;
173 }
174 
175 #define FSR_ERR_CLEAR   0x0063
176 #define RDRF_CLEAR      0x00fc
177 void handle_error(void)
178 {
179 
180 	(void)*SCFSR;
181 	*SCFSR = FSR_ERR_CLEAR;
182 	(void)*SCLSR;
183 	*SCLSR = 0x00;
184 }
185 
186 int serial_getc_check(void)
187 {
188 	unsigned short status;
189 
190 	status = *SCFSR;
191 
192 	if (status & (FSR_FER | FSR_ER | FSR_BRK))
193 		handle_error();
194 	if (*SCLSR & LSR_ORER)
195 		handle_error();
196 	return (status & (FSR_DR | FSR_RDF));
197 }
198 
199 int serial_getc(void)
200 {
201 	unsigned short status;
202 	char ch;
203 	while (!serial_getc_check()) ;
204 
205 	ch = *SCFRDR;
206 	status = *SCFSR;
207 
208 	*SCFSR = RDRF_CLEAR;
209 
210 	if (status & (FSR_FER | FSR_FER | FSR_ER | FSR_BRK))
211 		handle_error();
212 
213 	if (*SCLSR & LSR_ORER)
214 		handle_error();
215 
216 	return ch;
217 }
218 
219 #endif /* CFG_SCIF_CONSOLE */
220