aboutsummaryrefslogtreecommitdiff
path: root/arch/mips/vr4181/osprey/dbg_io.c
blob: 5e8a84072d5ba858d1228406da986d232f2f61ec (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
/*
 * kgdb io functions for osprey.  We use the serial port on debug board.
 *
 * Copyright (C) 2001 MontaVista Software Inc.
 * Author: jsun@mvista.com or jsun@junsun.net
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 *
 */

/* ======================= CONFIG ======================== */

/* [jsun] we use the second serial port for kdb */
#define         BASE                    0xb7fffff0
#define         MAX_BAUD                115200

/* distance in bytes between two serial registers */
#define         REG_OFFSET              1

/*
 * 0 - kgdb does serial init
 * 1 - kgdb skip serial init
 */
static int remoteDebugInitialized = 1;

/*
 * the default baud rate *if* kgdb does serial init
 */
#define		BAUD_DEFAULT		UART16550_BAUD_38400

/* ======================= END OF CONFIG ======================== */

typedef unsigned char uint8;
typedef unsigned int uint32;

#define         UART16550_BAUD_2400             2400
#define         UART16550_BAUD_4800             4800
#define         UART16550_BAUD_9600             9600
#define         UART16550_BAUD_19200            19200
#define         UART16550_BAUD_38400            38400
#define         UART16550_BAUD_57600            57600
#define         UART16550_BAUD_115200           115200

#define         UART16550_PARITY_NONE           0
#define         UART16550_PARITY_ODD            0x08
#define         UART16550_PARITY_EVEN           0x18
#define         UART16550_PARITY_MARK           0x28
#define         UART16550_PARITY_SPACE          0x38

#define         UART16550_DATA_5BIT             0x0
#define         UART16550_DATA_6BIT             0x1
#define         UART16550_DATA_7BIT             0x2
#define         UART16550_DATA_8BIT             0x3

#define         UART16550_STOP_1BIT             0x0
#define         UART16550_STOP_2BIT             0x4

/* register offset */
#define         OFS_RCV_BUFFER          0
#define         OFS_TRANS_HOLD          0
#define         OFS_SEND_BUFFER         0
#define         OFS_INTR_ENABLE         (1*REG_OFFSET)
#define         OFS_INTR_ID             (2*REG_OFFSET)
#define         OFS_DATA_FORMAT         (3*REG_OFFSET)
#define         OFS_LINE_CONTROL        (3*REG_OFFSET)
#define         OFS_MODEM_CONTROL       (4*REG_OFFSET)
#define         OFS_RS232_OUTPUT        (4*REG_OFFSET)
#define         OFS_LINE_STATUS         (5*REG_OFFSET)
#define         OFS_MODEM_STATUS        (6*REG_OFFSET)
#define         OFS_RS232_INPUT         (6*REG_OFFSET)
#define         OFS_SCRATCH_PAD         (7*REG_OFFSET)

#define         OFS_DIVISOR_LSB         (0*REG_OFFSET)
#define         OFS_DIVISOR_MSB         (1*REG_OFFSET)


/* memory-mapped read/write of the port */
#define         UART16550_READ(y)    (*((volatile uint8*)(BASE + y)))
#define         UART16550_WRITE(y, z)  ((*((volatile uint8*)(BASE + y))) = z)

void debugInit(uint32 baud, uint8 data, uint8 parity, uint8 stop)
{
        /* disable interrupts */
        UART16550_WRITE(OFS_INTR_ENABLE, 0);

        /* set up buad rate */
        {
                uint32 divisor;

                /* set DIAB bit */
                UART16550_WRITE(OFS_LINE_CONTROL, 0x80);

                /* set divisor */
                divisor = MAX_BAUD / baud;
                UART16550_WRITE(OFS_DIVISOR_LSB, divisor & 0xff);
                UART16550_WRITE(OFS_DIVISOR_MSB, (divisor & 0xff00) >> 8);

                /* clear DIAB bit */
                UART16550_WRITE(OFS_LINE_CONTROL, 0x0);
        }

        /* set data format */
        UART16550_WRITE(OFS_DATA_FORMAT, data | parity | stop);
}


uint8 getDebugChar(void)
{
        if (!remoteDebugInitialized) {
                remoteDebugInitialized = 1;
                debugInit(BAUD_DEFAULT,
                          UART16550_DATA_8BIT,
                          UART16550_PARITY_NONE, UART16550_STOP_1BIT);
        }

        while ((UART16550_READ(OFS_LINE_STATUS) & 0x1) == 0);
        return UART16550_READ(OFS_RCV_BUFFER);
}


int putDebugChar(uint8 byte)
{
        if (!remoteDebugInitialized) {
                remoteDebugInitialized = 1;
                debugInit(BAUD_DEFAULT,
                          UART16550_DATA_8BIT,
                          UART16550_PARITY_NONE, UART16550_STOP_1BIT);
        }

        while ((UART16550_READ(OFS_LINE_STATUS) & 0x20) == 0);
        UART16550_WRITE(OFS_SEND_BUFFER, byte);
        return 1;
}