ser.c

eCos操作系统源码

//=============================================================================
//
//      ser.c
//
//      Simple driver for the MDSChip serial port
//
//=============================================================================
//####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
//
// eCos 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 or (at your option) any later version.
//
// eCos is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License along
// with eCos; if not, write to the Free Software Foundation, Inc.,
// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
//
// As a special exception, if other files instantiate templates or use macros
// or inline functions from this file, or you compile this file and link it
// with other works to produce a work based on this file, this file does not
// by itself cause the resulting work to be covered by the GNU General Public
// License. However the source code for this file must still be made available
// in accordance with section (3) of the GNU General Public License.
//
// This exception does not invalidate any other reasons why a work based on
// this file might be covered by the GNU General Public License.
//
// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
// at http://sources.redhat.com/ecos/ecos-license/
// -------------------------------------------
//####ECOSGPLCOPYRIGHTEND####
//=============================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):   msalter
// Contributors:msalter
// Date:        2001-02-12
// Description: Simple driver for the MDSChip serial port
//
//####DESCRIPTIONEND####
//
//=============================================================================

#include <pkgconf/hal.h>
#include <pkgconf/system.h>
#include CYGBLD_HAL_PLATFORM_H

#include <cyg/hal/hal_arch.h>           // SAVE/RESTORE GP macros
#include <cyg/hal/hal_io.h>             // IO macros
#include <cyg/hal/hal_if.h>             // interface API
#include <cyg/hal/hal_intr.h>           // HAL_ENABLE/MASK/UNMASK_INTERRUPTS
#include <cyg/hal/hal_misc.h>           // Helper functions
#include <cyg/hal/drv_api.h>            // CYG_ISR_HANDLED

// We have no control over baud rate
#if CYGNUM_HAL_VIRTUAL_VECTOR_CONSOLE_CHANNEL_BAUD==57600
#define CYG_DEV_SERIAL_BAUD_DIVISOR    BAUD_57600
#endif

#ifndef CYG_DEV_SERIAL_BAUD_DIVISOR
#error Missing/incorrect serial baud rate defined - CDL error?
#endif

//-----------------------------------------------------------------------------
typedef struct {
    cyg_uint8* base;
    cyg_int32 msec_timeout;
    int isr_vector;
} channel_data_t;

static channel_data_t channels[1] = {
    { (cyg_uint8*)0, 1000, 0}
};

//-----------------------------------------------------------------------------
// The minimal init, get and put functions. All by polling.

void
cyg_hal_plf_serial_init_channel(void* __ch_data)
{
    cyg_hal_plf_write_sr_rbr(0);
    cyg_hal_plf_write_sr_tbr(0);
    cyg_hal_plf_write_tbr(0);
    cyg_hal_plf_write_rbr(0);
}

void
cyg_hal_plf_serial_putc(void* __ch_data, cyg_uint8 __ch)
{
    // wait for tx rdy
    while (cyg_hal_plf_read_sr_tbr() != 0) ;

    // Now, write it
    cyg_hal_plf_write_tbr(__ch);

    // and set TBR
    cyg_hal_plf_write_sr_tbr(1);
}

static cyg_bool
cyg_hal_plf_serial_getc_nonblock(void* __ch_data, cyg_uint8* ch)
{
    if (cyg_hal_plf_read_sr_rbr() == 0)
	return false;

    *ch = cyg_hal_plf_read_rbr();

    cyg_hal_plf_write_sr_rbr(0);

    return true;
}

cyg_uint8
cyg_hal_plf_serial_getc(void* __ch_data)
{
    cyg_uint8 ch;

    while(!cyg_hal_plf_serial_getc_nonblock(__ch_data, &ch));

    return ch;
}

static void
cyg_hal_plf_serial_write(void* __ch_data, const cyg_uint8* __buf, 
                         cyg_uint32 __len)
{
    while(__len-- > 0)
        cyg_hal_plf_serial_putc(__ch_data, *__buf++);
}

static void
cyg_hal_plf_serial_read(void* __ch_data, cyg_uint8* __buf, cyg_uint32 __len)
{
    while(__len-- > 0)
        *__buf++ = cyg_hal_plf_serial_getc(__ch_data);
}


cyg_bool
cyg_hal_plf_serial_getc_timeout(void* __ch_data, cyg_uint8* ch)
{
    int delay_count;
    channel_data_t* chan;
    cyg_bool res;

    // Some of the diagnostic print code calls through here with no idea what the ch_data is.
    // Go ahead and assume it is channels[0].
    if (__ch_data == 0)
      __ch_data = (void*)&channels[0];

    chan = (channel_data_t*)__ch_data;

    delay_count = chan->msec_timeout * 10; // delay in .1 ms steps

    for(;;) {
        res = cyg_hal_plf_serial_getc_nonblock(__ch_data, ch);
        if (res || 0 == delay_count--)
            break;
        CYGACC_CALL_IF_DELAY_US(100);
    }

    return res;
}

static int
cyg_hal_plf_serial_control(void *__ch_data, __comm_control_cmd_t __func, ...)
{
    static int irq_state = 0;
    channel_data_t* chan;
    int ret = 0;

    // Some of the diagnostic print code calls through here with no idea what the ch_data is.
    // Go ahead and assume it is channels[0].
    if (__ch_data == 0)
      __ch_data = (void*)&channels[0];

    chan = (channel_data_t*)__ch_data;

    switch (__func) {
    case __COMMCTL_IRQ_ENABLE:
        irq_state = 1;

        HAL_INTERRUPT_SET_LEVEL(chan->isr_vector, 1);
        HAL_INTERRUPT_UNMASK(chan->isr_vector);
        break;
    case __COMMCTL_IRQ_DISABLE:
        ret = irq_state;
        irq_state = 0;

        HAL_INTERRUPT_MASK(chan->isr_vector);
        break;
    case __COMMCTL_DBG_ISR_VECTOR:
        ret = chan->isr_vector;
        break;
    case __COMMCTL_SET_TIMEOUT:
    {
        va_list ap;

        va_start(ap, __func);

        ret = chan->msec_timeout;
        chan->msec_timeout = va_arg(ap, cyg_uint32);

        va_end(ap);
    }        
    break;
    case __COMMCTL_SETBAUD:
    {
	cyg_uint32 baud_rate;
        va_list ap;

        va_start(ap, __func);
        baud_rate = va_arg(ap, cyg_uint32);
        va_end(ap);

        switch (baud_rate)
        {
        case 57600:  break;
        default:     return -1;
        }
    }
    break;

    case __COMMCTL_GETBAUD:
        break;
    default:
        break;
    }
    return ret;
}

static int
cyg_hal_plf_serial_isr(void *__ch_data, int* __ctrlc, 
                       CYG_ADDRWORD __vector, CYG_ADDRWORD __data)
{
    *__ctrlc = 0;
    return 0;
}

static void
cyg_hal_plf_serial_init(void)
{
    hal_virtual_comm_table_t* comm;
    int cur = CYGACC_CALL_IF_SET_CONSOLE_COMM(CYGNUM_CALL_IF_SET_COMM_ID_QUERY_CURRENT);

    // Disable interrupts.
    HAL_INTERRUPT_MASK(channels[0].isr_vector);

    // Init channels
    cyg_hal_plf_serial_init_channel((void*)&channels[0]);
    
    // Setup procs in the vector table

    // Set channel 0
    CYGACC_CALL_IF_SET_CONSOLE_COMM(0);
    comm = CYGACC_CALL_IF_CONSOLE_PROCS();
    CYGACC_COMM_IF_CH_DATA_SET(*comm, &channels[0]);
    CYGACC_COMM_IF_WRITE_SET(*comm, cyg_hal_plf_serial_write);
    CYGACC_COMM_IF_READ_SET(*comm, cyg_hal_plf_serial_read);
    CYGACC_COMM_IF_PUTC_SET(*comm, cyg_hal_plf_serial_putc);
    CYGACC_COMM_IF_GETC_SET(*comm, cyg_hal_plf_serial_getc);
    CYGACC_COMM_IF_CONTROL_SET(*comm, cyg_hal_plf_serial_control);
    CYGACC_COMM_IF_DBG_ISR_SET(*comm, cyg_hal_plf_serial_isr);
    CYGACC_COMM_IF_GETC_TIMEOUT_SET(*comm, cyg_hal_plf_serial_getc_timeout);

    // Restore original console
    CYGACC_CALL_IF_SET_CONSOLE_COMM(cur);
}

void
cyg_hal_plf_comms_init(void)
{
    static int initialized = 0;

    if (initialized)
        return;

    initialized = 1;

    cyg_hal_plf_serial_init();
}

//-----------------------------------------------------------------------------
// end of ser16c550c.c