//==========================================================================
//
//      io/serial/mips/vrc437x_serial.c
//
//      Mips VRC437X Serial I/O Interface Module (interrupt driven)
//
//==========================================================================
//####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
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// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
// for more details.
//
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// 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
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//####ECOSGPLCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):    gthomas
// Contributors: gthomas
// Date:         1999-04-15
// Purpose:      VRC437X Serial I/O module (interrupt driven version)
// Description: 
//
//####DESCRIPTIONEND####
//
//==========================================================================

#include <pkgconf/system.h>
#include <pkgconf/io_serial.h>
#include <pkgconf/io.h>
#include <cyg/io/io.h>
#include <cyg/hal/hal_intr.h>
#include <cyg/io/devtab.h>
#include <cyg/io/serial.h>

#ifdef CYGPKG_IO_SERIAL_MIPS_VRC437X

#include "vrc437x_serial.h"

#if defined(CYGPKG_HAL_MIPS_LSBFIRST)
#define VRC437X_SCC_BASE 0xC1000000
#elif defined(CYGPKG_HAL_MIPS_MSBFIRST)
#define VRC437X_SCC_BASE 0xC1000003
#else
#error MIPS endianness not defined by configuration
#endif

#define VRC437X_SCC_INT  CYGNUM_HAL_INTERRUPT_DUART
#define SCC_CHANNEL_A             4
#define SCC_CHANNEL_B             0

extern void diag_printf(const char *fmt, ...);

typedef struct vrc437x_serial_info {
    CYG_ADDRWORD   base;
    unsigned char  regs[16];   // Known register state (since hardware is write-only!)
} vrc437x_serial_info;

static bool vrc437x_serial_init(struct cyg_devtab_entry *tab);
static bool vrc437x_serial_putc(serial_channel *chan, unsigned char c);
static Cyg_ErrNo vrc437x_serial_lookup(struct cyg_devtab_entry **tab, 
                                       struct cyg_devtab_entry *sub_tab,
                                       const char *name);
static unsigned char vrc437x_serial_getc(serial_channel *chan);
static Cyg_ErrNo vrc437x_serial_set_config(serial_channel *chan, cyg_uint32 key,
                                           const void *xbuf, cyg_uint32 *len);
static void vrc437x_serial_start_xmit(serial_channel *chan);
static void vrc437x_serial_stop_xmit(serial_channel *chan);

static cyg_uint32 vrc437x_serial_ISR(cyg_vector_t vector, cyg_addrword_t data);
static void       vrc437x_serial_DSR(cyg_vector_t vector, cyg_ucount32 count, cyg_addrword_t data);

static SERIAL_FUNS(vrc437x_serial_funs, 
                   vrc437x_serial_putc, 
                   vrc437x_serial_getc,
                   vrc437x_serial_set_config,
                   vrc437x_serial_start_xmit,
                   vrc437x_serial_stop_xmit
    );

#ifdef CYGPKG_IO_SERIAL_MIPS_VRC437X_SERIAL0
static vrc437x_serial_info vrc437x_serial_info0 = {VRC437X_SCC_BASE+SCC_CHANNEL_A};
#if CYGNUM_IO_SERIAL_MIPS_VRC437X_SERIAL0_BUFSIZE > 0
static unsigned char vrc437x_serial_out_buf0[CYGNUM_IO_SERIAL_MIPS_VRC437X_SERIAL0_BUFSIZE];
static unsigned char vrc437x_serial_in_buf0[CYGNUM_IO_SERIAL_MIPS_VRC437X_SERIAL0_BUFSIZE];

static SERIAL_CHANNEL_USING_INTERRUPTS(vrc437x_serial_channel0,
                                       vrc437x_serial_funs, 
                                       vrc437x_serial_info0,
                                       CYG_SERIAL_BAUD_RATE(CYGNUM_IO_SERIAL_MIPS_VRC437X_SERIAL0_BAUD),
                                       CYG_SERIAL_STOP_DEFAULT,
                                       CYG_SERIAL_PARITY_DEFAULT,
                                       CYG_SERIAL_WORD_LENGTH_DEFAULT,
                                       CYG_SERIAL_FLAGS_DEFAULT,
                                       &vrc437x_serial_out_buf0[0], sizeof(vrc437x_serial_out_buf0),
                                       &vrc437x_serial_in_buf0[0], sizeof(vrc437x_serial_in_buf0)
    );
#else
static SERIAL_CHANNEL(vrc437x_serial_channel0,
                      vrc437x_serial_funs, 
                      vrc437x_serial_info0,
                      CYG_SERIAL_BAUD_RATE(CYGNUM_IO_SERIAL_MIPS_VRC437X_SERIAL0_BAUD),
                      CYG_SERIAL_STOP_DEFAULT,
                      CYG_SERIAL_PARITY_DEFAULT,
                      CYG_SERIAL_WORD_LENGTH_DEFAULT,
                      CYG_SERIAL_FLAGS_DEFAULT
    );
#endif

DEVTAB_ENTRY(vrc437x_serial_io0, 
             CYGDAT_IO_SERIAL_MIPS_VRC437X_SERIAL0_NAME,
             0,                     // Does not depend on a lower level interface
             &cyg_io_serial_devio, 
             vrc437x_serial_init, 
             vrc437x_serial_lookup,     // Serial driver may need initializing
             &vrc437x_serial_channel0
    );
#endif //  CYGPKG_IO_SERIAL_MIPS_VRC437X_SERIAL0

#ifdef CYGPKG_IO_SERIAL_MIPS_VRC437X_SERIAL1
static vrc437x_serial_info vrc437x_serial_info1 = {VRC437X_SCC_BASE+SCC_CHANNEL_B};
#if CYGNUM_IO_SERIAL_MIPS_VRC437X_SERIAL1_BUFSIZE > 0
static unsigned char vrc437x_serial_out_buf1[CYGNUM_IO_SERIAL_MIPS_VRC437X_SERIAL1_BUFSIZE];
static unsigned char vrc437x_serial_in_buf1[CYGNUM_IO_SERIAL_MIPS_VRC437X_SERIAL1_BUFSIZE];

static SERIAL_CHANNEL_USING_INTERRUPTS(vrc437x_serial_channel1,
                                       vrc437x_serial_funs, 
                                       vrc437x_serial_info1,
                                       CYG_SERIAL_BAUD_RATE(CYGNUM_IO_SERIAL_MIPS_VRC437X_SERIAL1_BAUD),
                                       CYG_SERIAL_STOP_DEFAULT,
                                       CYG_SERIAL_PARITY_DEFAULT,
                                       CYG_SERIAL_WORD_LENGTH_DEFAULT,
                                       CYG_SERIAL_FLAGS_DEFAULT,
                                       &vrc437x_serial_out_buf1[0], sizeof(vrc437x_serial_out_buf1),
                                       &vrc437x_serial_in_buf1[0], sizeof(vrc437x_serial_in_buf1)
    );
#else
static SERIAL_CHANNEL(vrc437x_serial_channel1,
                      vrc437x_serial_funs, 
                      vrc437x_serial_info1,
                      CYG_SERIAL_BAUD_RATE(CYGNUM_IO_SERIAL_MIPS_VRC437X_SERIAL1_BAUD),
                      CYG_SERIAL_STOP_DEFAULT,
                      CYG_SERIAL_PARITY_DEFAULT,
                      CYG_SERIAL_WORD_LENGTH_DEFAULT,
                      CYG_SERIAL_FLAGS_DEFAULT
    );
#endif

DEVTAB_ENTRY(vrc437x_serial_io1, 
             CYGDAT_IO_SERIAL_MIPS_VRC437X_SERIAL1_NAME,
             0,                     // Does not depend on a lower level interface
             &cyg_io_serial_devio, 
             vrc437x_serial_init, 
             vrc437x_serial_lookup,     // Serial driver may need initializing
             &vrc437x_serial_channel1
    );
#endif //  CYGPKG_IO_SERIAL_MIPS_VRC437X_SERIAL1

static cyg_interrupt  vrc437x_serial_interrupt;
static cyg_handle_t   vrc437x_serial_interrupt_handle;

// Table which maps hardware channels (A,B) to software ones
struct serial_channel *vrc437x_chans[] = {
#ifdef CYGPKG_IO_SERIAL_MIPS_VRC437X_SERIAL0    // Hardware channel A
    &vrc437x_serial_channel0,        
#else
    0,
#endif
#ifdef CYGPKG_IO_SERIAL_MIPS_VRC437X_SERIAL1    // Hardware channel B
    &vrc437x_serial_channel1,
#else
    0,
#endif
};

// Support functions which access the serial device.  Note that this chip requires
// a substantial delay after each access. 

#define SCC_DELAY 100
inline static void
scc_delay(void)
{
    int i;
    for (i = 0;  i < SCC_DELAY;  i++) ;
}

inline static void
scc_write_reg(volatile unsigned char *reg, unsigned char val)
{
    scc_delay();
    *reg = val;
}

inline static unsigned char
scc_read_reg(volatile unsigned char *reg)
{
    unsigned char val;
    scc_delay();
    val = *reg;
    return (val);
}

inline static unsigned char
scc_read_ctl(volatile struct serial_port *port, int reg)
{
    if (reg != 0) {
        scc_write_reg(&port->scc_ctl, reg);
    }       
    return (scc_read_reg(&port->scc_ctl));
}

inline static void
scc_write_ctl(volatile struct serial_port *port, int reg, unsigned char val)
{
    if (reg != 0) {
        scc_write_reg(&port->scc_ctl, reg);
    }       
    scc_write_reg(&port->scc_ctl, val);
}

inline static unsigned char
scc_read_dat(volatile struct serial_port *port)
{