Merge master.kernel.org:/home/rmk/linux-2.6-serial
[linux-2.6.git] / arch / mips / pmc-sierra / yosemite / dbg_io.c
1 /*
2  * Copyright 2003 PMC-Sierra
3  * Author: Manish Lachwani (lachwani@pmc-sierra.com)
4  *
5  *  This program is free software; you can redistribute  it and/or modify it
6  *  under  the terms of  the GNU General  Public License as published by the
7  *  Free Software Foundation;  either version 2 of the  License, or (at your
8  *  option) any later version.
9  *
10  *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
11  *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
12  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
13  *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
14  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
15  *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
16  *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
17  *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
18  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
19  *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
20  *
21  *  You should have received a copy of the  GNU General Public License along
22  *  with this program; if not, write  to the Free Software Foundation, Inc.,
23  *  675 Mass Ave, Cambridge, MA 02139, USA.
24  */
25
26 /*
27  * Support for KGDB for the Yosemite board. We make use of single serial
28  * port to be used for KGDB as well as console. The second serial port
29  * seems to be having a problem. Single IRQ is allocated for both the
30  * ports. Hence, the interrupt routing code needs to figure out whether
31  * the interrupt came from channel A or B.
32  */
33
34 #include <asm/serial.h>
35
36 /*
37  * Baud rate, Parity, Data and Stop bit settings for the
38  * serial port on the Yosemite. Note that the Early printk
39  * patch has been added. So, we should be all set to go
40  */
41 #define YOSEMITE_BAUD_2400      2400
42 #define YOSEMITE_BAUD_4800      4800
43 #define YOSEMITE_BAUD_9600      9600
44 #define YOSEMITE_BAUD_19200     19200
45 #define YOSEMITE_BAUD_38400     38400
46 #define YOSEMITE_BAUD_57600     57600
47 #define YOSEMITE_BAUD_115200    115200
48
49 #define YOSEMITE_PARITY_NONE    0
50 #define YOSEMITE_PARITY_ODD     0x08
51 #define YOSEMITE_PARITY_EVEN    0x18
52 #define YOSEMITE_PARITY_MARK    0x28
53 #define YOSEMITE_PARITY_SPACE   0x38
54
55 #define YOSEMITE_DATA_5BIT      0x0
56 #define YOSEMITE_DATA_6BIT      0x1
57 #define YOSEMITE_DATA_7BIT      0x2
58 #define YOSEMITE_DATA_8BIT      0x3
59
60 #define YOSEMITE_STOP_1BIT      0x0
61 #define YOSEMITE_STOP_2BIT      0x4
62
63 /* This is crucial */
64 #define SERIAL_REG_OFS          0x1
65
66 #define SERIAL_RCV_BUFFER       0x0
67 #define SERIAL_TRANS_HOLD       0x0
68 #define SERIAL_SEND_BUFFER      0x0
69 #define SERIAL_INTR_ENABLE      (1 * SERIAL_REG_OFS)
70 #define SERIAL_INTR_ID          (2 * SERIAL_REG_OFS)
71 #define SERIAL_DATA_FORMAT      (3 * SERIAL_REG_OFS)
72 #define SERIAL_LINE_CONTROL     (3 * SERIAL_REG_OFS)
73 #define SERIAL_MODEM_CONTROL    (4 * SERIAL_REG_OFS)
74 #define SERIAL_RS232_OUTPUT     (4 * SERIAL_REG_OFS)
75 #define SERIAL_LINE_STATUS      (5 * SERIAL_REG_OFS)
76 #define SERIAL_MODEM_STATUS     (6 * SERIAL_REG_OFS)
77 #define SERIAL_RS232_INPUT      (6 * SERIAL_REG_OFS)
78 #define SERIAL_SCRATCH_PAD      (7 * SERIAL_REG_OFS)
79
80 #define SERIAL_DIVISOR_LSB      (0 * SERIAL_REG_OFS)
81 #define SERIAL_DIVISOR_MSB      (1 * SERIAL_REG_OFS)
82
83 /*
84  * Functions to READ and WRITE to serial port 0
85  */
86 #define SERIAL_READ(ofs)                (*((volatile unsigned char*)    \
87                                         (TITAN_SERIAL_BASE + ofs)))
88
89 #define SERIAL_WRITE(ofs, val)          ((*((volatile unsigned char*)   \
90                                         (TITAN_SERIAL_BASE + ofs))) = val)
91
92 /*
93  * Functions to READ and WRITE to serial port 1
94  */
95 #define SERIAL_READ_1(ofs)              (*((volatile unsigned char*)    \
96                                         (TITAN_SERIAL_BASE_1 + ofs)
97
98 #define SERIAL_WRITE_1(ofs, val)        ((*((volatile unsigned char*)   \
99                                         (TITAN_SERIAL_BASE_1 + ofs))) = val)
100
101 /*
102  * Second serial port initialization
103  */
104 void init_second_port(void)
105 {
106         /* Disable Interrupts */
107         SERIAL_WRITE_1(SERIAL_LINE_CONTROL, 0x0);
108         SERIAL_WRITE_1(SERIAL_INTR_ENABLE, 0x0);
109
110         {
111                 unsigned int divisor;
112
113                 SERIAL_WRITE_1(SERIAL_LINE_CONTROL, 0x80);
114                 divisor = TITAN_SERIAL_BASE_BAUD / YOSEMITE_BAUD_115200;
115                 SERIAL_WRITE_1(SERIAL_DIVISOR_LSB, divisor & 0xff);
116
117                 SERIAL_WRITE_1(SERIAL_DIVISOR_MSB,
118                                (divisor & 0xff00) >> 8);
119                 SERIAL_WRITE_1(SERIAL_LINE_CONTROL, 0x0);
120         }
121
122         SERIAL_WRITE_1(SERIAL_DATA_FORMAT, YOSEMITE_DATA_8BIT |
123                        YOSEMITE_PARITY_NONE | YOSEMITE_STOP_1BIT);
124
125         /* Enable Interrupts */
126         SERIAL_WRITE_1(SERIAL_INTR_ENABLE, 0xf);
127 }
128
129 /* Initialize the serial port for KGDB debugging */
130 void debugInit(unsigned int baud, unsigned char data, unsigned char parity,
131                unsigned char stop)
132 {
133         /* Disable Interrupts */
134         SERIAL_WRITE(SERIAL_LINE_CONTROL, 0x0);
135         SERIAL_WRITE(SERIAL_INTR_ENABLE, 0x0);
136
137         {
138                 unsigned int divisor;
139
140                 SERIAL_WRITE(SERIAL_LINE_CONTROL, 0x80);
141
142                 divisor = TITAN_SERIAL_BASE_BAUD / baud;
143                 SERIAL_WRITE(SERIAL_DIVISOR_LSB, divisor & 0xff);
144
145                 SERIAL_WRITE(SERIAL_DIVISOR_MSB, (divisor & 0xff00) >> 8);
146                 SERIAL_WRITE(SERIAL_LINE_CONTROL, 0x0);
147         }
148
149         SERIAL_WRITE(SERIAL_DATA_FORMAT, data | parity | stop);
150 }
151
152 static int remoteDebugInitialized = 0;
153
154 unsigned char getDebugChar(void)
155 {
156         if (!remoteDebugInitialized) {
157                 remoteDebugInitialized = 1;
158                 debugInit(YOSEMITE_BAUD_115200,
159                           YOSEMITE_DATA_8BIT,
160                           YOSEMITE_PARITY_NONE, YOSEMITE_STOP_1BIT);
161         }
162
163         while ((SERIAL_READ(SERIAL_LINE_STATUS) & 0x1) == 0);
164         return SERIAL_READ(SERIAL_RCV_BUFFER);
165 }
166
167 int putDebugChar(unsigned char byte)
168 {
169         if (!remoteDebugInitialized) {
170                 remoteDebugInitialized = 1;
171                 debugInit(YOSEMITE_BAUD_115200,
172                           YOSEMITE_DATA_8BIT,
173                           YOSEMITE_PARITY_NONE, YOSEMITE_STOP_1BIT);
174         }
175
176         while ((SERIAL_READ(SERIAL_LINE_STATUS) & 0x20) == 0);
177         SERIAL_WRITE(SERIAL_SEND_BUFFER, byte);
178
179         return 1;
180 }