//==========================================================================
//
//      io/serial/arm/aeb_serial.c
//
//      ARM AEB-1 Serial I/O Interface Module (interrupt driven)
//
//==========================================================================
//####COPYRIGHTBEGIN####
//                                                                          
// -------------------------------------------                              
// The contents of this file are subject to the Red Hat eCos Public License 
// Version 1.1 (the "License"); you may not use this file except in         
// compliance with the License.  You may obtain a copy of the License at    
// http://www.redhat.com/                                                   
//                                                                          
// Software distributed under the License is distributed on an "AS IS"      
// basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.  See the 
// License for the specific language governing rights and limitations under 
// the License.                                                             
//                                                                          
// The Original Code is eCos - Embedded Configurable Operating System,      
// released September 30, 1998.                                             
//                                                                          
// The Initial Developer of the Original Code is Red Hat.                   
// Portions created by Red Hat are                                          
// Copyright (C) 1998, 1999, 2000 Red Hat, Inc.                             
// All Rights Reserved.                                                     
// -------------------------------------------                              
//                                                                          
//####COPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):   gthomas
// Contributors:  gthomas
// Date:        1999-02-04
// Purpose:     AEB-1 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>
#include <cyg/infra/diag.h>

#ifdef CYGPKG_IO_SERIAL_ARM_AEB

#include "aeb_serial.h"

typedef struct aeb_serial_info {
    CYG_ADDRWORD   base;
    CYG_WORD       int_num;
    cyg_interrupt  serial_interrupt;
    cyg_handle_t   serial_interrupt_handle;
} aeb_serial_info;

static bool aeb_serial_init(struct cyg_devtab_entry *tab);
static bool aeb_serial_putc(serial_channel *chan, unsigned char c);
static Cyg_ErrNo aeb_serial_lookup(struct cyg_devtab_entry **tab, 
                                   struct cyg_devtab_entry *sub_tab,
                                   const char *name);
static unsigned char aeb_serial_getc(serial_channel *chan);
static bool aeb_serial_set_config(serial_channel *chan, cyg_serial_info_t *config);
static void aeb_serial_start_xmit(serial_channel *chan);
static void aeb_serial_stop_xmit(serial_channel *chan);

static cyg_uint32 aeb_serial_ISR(cyg_vector_t vector, cyg_addrword_t data);
static void       aeb_serial_DSR(cyg_vector_t vector, cyg_ucount32 count, cyg_addrword_t data);

static SERIAL_FUNS(aeb_serial_funs, 
                   aeb_serial_putc, 
                   aeb_serial_getc,
                   aeb_serial_set_config,
                   aeb_serial_start_xmit,
                   aeb_serial_stop_xmit
    );

#ifdef CYGPKG_IO_SERIAL_ARM_AEB_SERIAL0
static aeb_serial_info aeb_serial_info0 = {0xFFFF0000, 
                                           CYGNUM_HAL_INTERRUPT_UART0};
#if CYGNUM_IO_SERIAL_ARM_AEB_SERIAL0_BUFSIZE > 0
static unsigned char aeb_serial_out_buf0[CYGNUM_IO_SERIAL_ARM_AEB_SERIAL0_BUFSIZE];
static unsigned char aeb_serial_in_buf0[CYGNUM_IO_SERIAL_ARM_AEB_SERIAL0_BUFSIZE];

static SERIAL_CHANNEL_USING_INTERRUPTS(aeb_serial_channel0,
                                       aeb_serial_funs, 
                                       aeb_serial_info0,
                                       CYG_SERIAL_BAUD_RATE(CYGNUM_IO_SERIAL_ARM_AEB_SERIAL0_BAUD),
                                       CYG_SERIAL_STOP_DEFAULT,
                                       CYG_SERIAL_PARITY_DEFAULT,
                                       CYG_SERIAL_WORD_LENGTH_DEFAULT,
                                       CYG_SERIAL_FLAGS_DEFAULT,
                                       &aeb_serial_out_buf0[0], sizeof(aeb_serial_out_buf0),
                                       &aeb_serial_in_buf0[0], sizeof(aeb_serial_in_buf0)
    );
#else
static SERIAL_CHANNEL(aeb_serial_channel0,
                      aeb_serial_funs, 
                      aeb_serial_info0,
                      CYG_SERIAL_BAUD_RATE(CYGNUM_IO_SERIAL_ARM_AEB_SERIAL0_BAUD),
                      CYG_SERIAL_STOP_DEFAULT,
                      CYG_SERIAL_PARITY_DEFAULT,
                      CYG_SERIAL_WORD_LENGTH_DEFAULT,
                      CYG_SERIAL_FLAGS_DEFAULT
    );
#endif

DEVTAB_ENTRY(aeb_serial_io0, 
             CYGDAT_IO_SERIAL_ARM_AEB_SERIAL0_NAME,
             0,                     // Does not depend on a lower level interface
             &cyg_io_serial_devio, 
             aeb_serial_init, 
             aeb_serial_lookup,     // Serial driver may need initializing
             &aeb_serial_channel0
    );
#endif //  CYGPKG_IO_SERIAL_ARM_AEB_SERIAL0

#ifdef CYGPKG_IO_SERIAL_ARM_AEB_SERIAL1
static aeb_serial_info aeb_serial_info1 = {0xFFFF0400, 
                                           CYGNUM_HAL_INTERRUPT_UART1};
#if CYGNUM_IO_SERIAL_ARM_AEB_SERIAL1_BUFSIZE > 0
static unsigned char aeb_serial_out_buf1[CYGNUM_IO_SERIAL_ARM_AEB_SERIAL1_BUFSIZE];
static unsigned char aeb_serial_in_buf1[CYGNUM_IO_SERIAL_ARM_AEB_SERIAL1_BUFSIZE];

static SERIAL_CHANNEL_USING_INTERRUPTS(aeb_serial_channel1,
                                       aeb_serial_funs, 
                                       aeb_serial_info1,
                                       CYG_SERIAL_BAUD_RATE(CYGNUM_IO_SERIAL_ARM_AEB_SERIAL1_BAUD),
                                       CYG_SERIAL_STOP_DEFAULT,
                                       CYG_SERIAL_PARITY_DEFAULT,
                                       CYG_SERIAL_WORD_LENGTH_DEFAULT,
                                       CYG_SERIAL_FLAGS_DEFAULT,
                                       &aeb_serial_out_buf1[0], sizeof(aeb_serial_out_buf1),
                                       &aeb_serial_in_buf1[0], sizeof(aeb_serial_in_buf1)
    );
#else
static SERIAL_CHANNEL(aeb_serial_channel1,
                      aeb_serial_funs, 
                      aeb_serial_info1,
                      CYG_SERIAL_BAUD_RATE(CYGNUM_IO_SERIAL_ARM_AEB_SERIAL1_BAUD),
                      CYG_SERIAL_STOP_DEFAULT,
                      CYG_SERIAL_PARITY_DEFAULT,
                      CYG_SERIAL_WORD_LENGTH_DEFAULT,
                      CYG_SERIAL_FLAGS_DEFAULT
    );
#endif

DEVTAB_ENTRY(aeb_serial_io1, 
             CYGDAT_IO_SERIAL_ARM_AEB_SERIAL1_NAME,
             0,                     // Does not depend on a lower level interface
             &cyg_io_serial_devio, 
             aeb_serial_init, 
             aeb_serial_lookup,     // Serial driver may need initializing
             &aeb_serial_channel1
    );
#endif //  CYGPKG_IO_SERIAL_ARM_AEB_SERIAL1

// Internal function to actually configure the hardware to desired baud rate, etc.
static bool
aeb_serial_config_port(serial_channel *chan, cyg_serial_info_t *new_config, bool init)
{
    aeb_serial_info *aeb_chan = (aeb_serial_info *)chan->dev_priv;
    volatile struct serial_port *port = (volatile struct serial_port *)aeb_chan->base;
    unsigned short baud_divisor = select_baud[new_config->baud];
    unsigned char _lcr, _ier;
    if (baud_divisor == 0) return false;
    _ier = port->REG_IER;
    port->REG_IER = 0;  // Disable port interrupts while changing hardware
    _lcr = select_word_length[new_config->word_length - CYGNUM_SERIAL_WORD_LENGTH_5] | 
        select_stop_bits[new_config->stop] |
        select_parity[new_config->parity];
    port->REG_LCR = _lcr;
    port->REG_LCR |= LCR_DL;
    port->REG_MDL = baud_divisor >> 8;
    port->REG_LDL = baud_divisor & 0xFF;
    port->REG_LCR &= ~LCR_DL;
    if (init) {
        port->REG_FCR = 0x07;  // Enable and clear FIFO
        if (chan->out_cbuf.len != 0) {
            port->REG_IER = IER_RCV;
        } else {
            port->REG_IER = 0;
        }
        port->REG_MCR = MCR_INT|MCR_DTR|MCR_RTS;  // Master interrupt enable
    } else {
        port->REG_IER = _ier;
    }
    if (new_config != &chan->config) {
        chan->config = *new_config;
    }
    return true;
}

// Function to initialize the device.  Called at bootstrap time.
static bool 
aeb_serial_init(struct cyg_devtab_entry *tab)
{
    serial_channel *chan = (serial_channel *)tab->priv;
    aeb_serial_info *aeb_chan = (aeb_serial_info *)chan->dev_priv;
#ifdef CYGDBG_IO_INIT
    diag_printf("AEB SERIAL init - dev: %x.%d\n", aeb_chan->base, aeb_chan->int_num);
#endif
    (chan->callbacks->serial_init)(chan);  // Really only required for interrupt driven devices
    if (chan->out_cbuf.len != 0) {
        cyg_drv_interrupt_create(aeb_chan->int_num,
                                 99,                     // Priority - unused
                                 (cyg_addrword_t)chan,   //  Data item passed to interrupt handler
                                 aeb_serial_ISR,
                                 aeb_serial_DSR,
                                 &aeb_chan->serial_interrupt_handle,
                                 &aeb_chan->serial_interrupt);
        cyg_drv_interrupt_attach(aeb_chan->serial_interrupt_handle);
        cyg_drv_interrupt_unmask(aeb_chan->int_num);
    }
    aeb_serial_config_port(chan, &chan->config, true);
    return true;
}

// This routine is called when the device is "looked" up (i.e. attached)
static Cyg_ErrNo 
aeb_serial_lookup(struct cyg_devtab_entry **tab, 
                  struct cyg_devtab_entry *sub_tab,
                  const char *name)
{
    serial_channel *chan = (serial_channel *)(*tab)->priv;
    (chan->callbacks->serial_init)(chan);  // Really only required for interrupt driven devices
    return ENOERR;
}

// Send a character to the device output buffer.
// Return 'true' if character is sent to device
static bool
aeb_serial_putc(serial_channel *chan, unsigned char c)
{
    aeb_serial_info *aeb_chan = (aeb_serial_info *)chan->dev_priv;
    volatile struct serial_port *port = (volatile struct serial_port *)aeb_chan->base;
    if (port->REG_LSR & LSR_THE) {
// Transmit buffer is empty
        port->REG_THR = c;
        return true;
    } else {
// No space
        return false;
    }
}

// Fetch a character from the device input buffer, waiting if necessary
static unsigned char 
aeb_serial_getc(serial_channel *chan)
{
    unsigned char c;
    aeb_serial_info *aeb_chan = (aeb_serial_info *)chan->dev_priv;
    volatile struct serial_port *port = (volatile struct serial_port *)aeb_chan->base;
    while ((port->REG_LSR & LSR_RSR) == 0) ;   // Wait for char
    c = port->REG_RHR;
    return c;
}

// Set up the device characteristics; baud rate, etc.
static bool 
aeb_serial_set_config(serial_channel *chan, cyg_serial_info_t *config)
{
    return aeb_serial_config_port(chan, config, false);
}

// Enable the transmitter on the device
static void
aeb_serial_start_xmit(serial_channel *chan)
{
    aeb_serial_info *aeb_chan = (aeb_serial_info *)chan->dev_priv;
    volatile struct serial_port *port = (volatile struct serial_port *)aeb_chan->base;
    port->REG_IER |= IER_XMT;  // Enable xmit interrupt
}

// Disable the transmitter on the device
static void 
aeb_serial_stop_xmit(serial_channel *chan)
{
    aeb_serial_info *aeb_chan = (aeb_serial_info *)chan->dev_priv;
    volatile struct serial_port *port = (volatile struct serial_port *)aeb_chan->base;
    port->REG_IER &= ~IER_XMT;  // Disable xmit interrupt
}

// Serial I/O - low level interrupt handler (ISR)
static cyg_uint32 
aeb_serial_ISR(cyg_vector_t vector, cyg_addrword_t data)
{
    serial_channel *chan = (serial_channel *)data;
    aeb_serial_info *aeb_chan = (aeb_serial_info *)chan->dev_priv;
    cyg_drv_interrupt_mask(aeb_chan->int_num);
    cyg_drv_interrupt_acknowledge(aeb_chan->int_num);
    return CYG_ISR_CALL_DSR;  // Cause DSR to be run
}

// Serial I/O - high level interrupt handler (DSR)
static void       
aeb_serial_DSR(cyg_vector_t vector, cyg_ucount32 count, cyg_addrword_t data)
{
    serial_channel *chan = (serial_channel *)data;
    aeb_serial_info *aeb_chan = (aeb_serial_info *)chan->dev_priv;
    volatile struct serial_port *port = (volatile struct serial_port *)aeb_chan->base;
    unsigned char isr;
    isr = port->REG_ISR & 0x0E;
    if (isr == ISR_Tx) {
        (chan->callbacks->xmt_char)(chan);
    } else if (isr == ISR_Rx) {
        (chan->callbacks->rcv_char)(chan, port->REG_RHR);
    }
    cyg_drv_interrupt_unmask(aeb_chan->int_num);
}
#endif
