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[/] [openrisc/] [trunk/] [bootloaders/] [orpmon/] [drivers/] [uart.c] - Blame information for rev 247

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Line No. Rev Author Line
1 2 marcus.erl
#include "support.h"
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#include "board.h"
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#include "uart.h"
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#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
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#define WAIT_FOR_XMITR \
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        do { \
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                lsr = REG8(UART_BASE + UART_LSR); \
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        } while ((lsr & BOTH_EMPTY) != BOTH_EMPTY)
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#define WAIT_FOR_THRE \
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        do { \
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                lsr = REG8(UART_BASE + UART_LSR); \
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        } while ((lsr & UART_LSR_THRE) != UART_LSR_THRE)
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#define CHECK_FOR_CHAR (REG8(UART_BASE + UART_LSR) & UART_LSR_DR)
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#define WAIT_FOR_CHAR \
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         do { \
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                lsr = REG8(UART_BASE + UART_LSR); \
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         } while ((lsr & UART_LSR_DR) != UART_LSR_DR)
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#define UART_TX_BUFF_LEN 32
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#define UART_TX_BUFF_MASK (UART_TX_BUFF_LEN -1)
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char tx_buff[UART_TX_BUFF_LEN];
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volatile int tx_level, rx_level;
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void uart_init(void)
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{
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        int divisor;
33 140 julius
        float float_divisor;
34 246 julius
 
35 2 marcus.erl
        /* Reset receiver and transmiter */
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        REG8(UART_BASE + UART_FCR) = UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT | UART_FCR_TRIGGER_4;
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        /* Disable all interrupts */
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        REG8(UART_BASE + UART_IER) = 0x00;
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        /* Set 8 bit char, 1 stop bit, no parity */
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        REG8(UART_BASE + UART_LCR) = UART_LCR_WLEN8 & ~(UART_LCR_STOP | UART_LCR_PARITY);
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        /* Set baud rate */
45 140 julius
        float_divisor = (float) IN_CLK/(16 * UART_BAUD_RATE);
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        float_divisor += 0.50f; // Ensure round up
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        divisor = (int) float_divisor;
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49 2 marcus.erl
        REG8(UART_BASE + UART_LCR) |= UART_LCR_DLAB;
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        REG8(UART_BASE + UART_DLL) = divisor & 0x000000ff;
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        REG8(UART_BASE + UART_DLM) = (divisor >> 8) & 0x000000ff;
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        REG8(UART_BASE + UART_LCR) &= ~(UART_LCR_DLAB);
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}
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void uart_putc(char c)
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{
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        unsigned char lsr;
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        WAIT_FOR_THRE;
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        REG8(UART_BASE + UART_TX) = c;
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        if(c == '\n') {
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          WAIT_FOR_THRE;
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          REG8(UART_BASE + UART_TX) = '\r';
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        }
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        WAIT_FOR_XMITR;
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}
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char uart_getc(void)
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{
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        unsigned char lsr;
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        char c;
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        WAIT_FOR_CHAR;
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        c = REG8(UART_BASE + UART_RX);
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        return c;
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}
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char uart_testc(void)
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{
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        if((REG8(UART_BASE + UART_LSR) & UART_LSR_DR) == UART_LSR_DR)
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                return REG8(UART_BASE + UART_RX);
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        else
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                return 0;
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}

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