arch/mips/momentum/ocelot_g/dbg_io.c

   1
   2 #ifdef CONFIG_KGDB
   3
   4 #include <asm/serial.h> /* For the serial port location and base baud */
   5
   6 /* --- CONFIG --- */
   7
   8 typedef unsigned char uint8;
   9 typedef unsigned int uint32;
  10
  11 /* --- END OF CONFIG --- */
  12
  13 #define         UART16550_BAUD_2400             2400
  14 #define         UART16550_BAUD_4800             4800
  15 #define         UART16550_BAUD_9600             9600
  16 #define         UART16550_BAUD_19200            19200
  17 #define         UART16550_BAUD_38400            38400
  18 #define         UART16550_BAUD_57600            57600
  19 #define         UART16550_BAUD_115200           115200
  20
  21 #define         UART16550_PARITY_NONE           0
  22 #define         UART16550_PARITY_ODD            0x08
  23 #define         UART16550_PARITY_EVEN           0x18
  24 #define         UART16550_PARITY_MARK           0x28
  25 #define         UART16550_PARITY_SPACE          0x38
  26
  27 #define         UART16550_DATA_5BIT             0x0
  28 #define         UART16550_DATA_6BIT             0x1
  29 #define         UART16550_DATA_7BIT             0x2
  30 #define         UART16550_DATA_8BIT             0x3
  31
  32 #define         UART16550_STOP_1BIT             0x0
  33 #define         UART16550_STOP_2BIT             0x4
  34
  35 /* ----------------------------------------------------- */
  36
  37 /* === CONFIG === */
  38
  39 /* [jsun] we use the second serial port for kdb */
  40 #define         BASE                    OCELOT_SERIAL1_BASE
  41 #define         MAX_BAUD                OCELOT_BASE_BAUD
  42
  43 /* === END OF CONFIG === */
  44
  45 #define         REG_OFFSET              4
  46
  47 /* register offset */
  48 #define         OFS_RCV_BUFFER          0
  49 #define         OFS_TRANS_HOLD          0
  50 #define         OFS_SEND_BUFFER         0
  51 #define         OFS_INTR_ENABLE         (1*REG_OFFSET)
  52 #define         OFS_INTR_ID             (2*REG_OFFSET)
  53 #define         OFS_DATA_FORMAT         (3*REG_OFFSET)
  54 #define         OFS_LINE_CONTROL        (3*REG_OFFSET)
  55 #define         OFS_MODEM_CONTROL       (4*REG_OFFSET)
  56 #define         OFS_RS232_OUTPUT        (4*REG_OFFSET)
  57 #define         OFS_LINE_STATUS         (5*REG_OFFSET)
  58 #define         OFS_MODEM_STATUS        (6*REG_OFFSET)
  59 #define         OFS_RS232_INPUT         (6*REG_OFFSET)
  60 #define         OFS_SCRATCH_PAD         (7*REG_OFFSET)
  61
  62 #define         OFS_DIVISOR_LSB         (0*REG_OFFSET)
  63 #define         OFS_DIVISOR_MSB         (1*REG_OFFSET)
  64
  65
  66 /* memory-mapped read/write of the port */
  67 #define         UART16550_READ(y)    (*((volatile uint8*)(BASE + y)))
  68 #define         UART16550_WRITE(y, z)  ((*((volatile uint8*)(BASE + y))) = z)
  69
  70 void debugInit(uint32 baud, uint8 data, uint8 parity, uint8 stop)
  71 {
  72         /* disable interrupts */
  73         UART16550_WRITE(OFS_INTR_ENABLE, 0);
  74
  75         /* set up baud rate */
  76         {
  77                 uint32 divisor;
  78
  79                 /* set DIAB bit */
  80                 UART16550_WRITE(OFS_LINE_CONTROL, 0x80);
  81
  82                 /* set divisor */
  83                 divisor = MAX_BAUD / baud;
  84                 UART16550_WRITE(OFS_DIVISOR_LSB, divisor & 0xff);
  85                 UART16550_WRITE(OFS_DIVISOR_MSB, (divisor & 0xff00) >> 8);
  86
  87                 /* clear DIAB bit */
  88                 UART16550_WRITE(OFS_LINE_CONTROL, 0x0);
  89         }
  90
  91         /* set data format */
  92         UART16550_WRITE(OFS_DATA_FORMAT, data | parity | stop);
  93 }
  94
  95 static int remoteDebugInitialized = 0;
  96
  97 uint8 getDebugChar(void)
  98 {
  99         if (!remoteDebugInitialized) {
 100                 remoteDebugInitialized = 1;
 101                 debugInit(UART16550_BAUD_38400,
 102                           UART16550_DATA_8BIT,
 103                           UART16550_PARITY_NONE, UART16550_STOP_1BIT);
 104         }
 105
 106         while ((UART16550_READ(OFS_LINE_STATUS) & 0x1) == 0);
 107         return UART16550_READ(OFS_RCV_BUFFER);
 108 }
 109
 110
 111 int putDebugChar(uint8 byte)
 112 {
 113         if (!remoteDebugInitialized) {
 114                 remoteDebugInitialized = 1;
 115                 debugInit(UART16550_BAUD_38400,
 116                           UART16550_DATA_8BIT,
 117                           UART16550_PARITY_NONE, UART16550_STOP_1BIT);
 118         }
 119
 120         while ((UART16550_READ(OFS_LINE_STATUS) & 0x20) == 0);
 121         UART16550_WRITE(OFS_SEND_BUFFER, byte);
 122         return 1;
 123 }
 124
 125 #endif