//=============================================================================
//
//      ns16552.c
//
//      Simple driver for the NS16652 serial controller
//
//=============================================================================
// ####ECOSGPLCOPYRIGHTBEGIN####                                            
// -------------------------------------------                              
// This file is part of eCos, the Embedded Configurable Operating System.   
// Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, 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.,    
// 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 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 v2.                                               
//
// This exception does not invalidate any other reasons why a work based    
// on this file might be covered by the GNU General Public License.         
// -------------------------------------------                              
// ####ECOSGPLCOPYRIGHTEND####                                              
//=============================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):   nickg, gthomas
// Contributors:nickg, gthomas, jskov
// Date:        1998-03-02
// Description: Simple HAL driver for the NS16552 serial controller
// Note:        To drop into a new HAL, you should only have to change the
//              few parameters here at the top.
//####DESCRIPTIONEND####
//
//=============================================================================

#include <pkgconf/hal.h>
#include <cyg/infra/cyg_type.h>         // base types

#include <cyg/infra/cyg_trac.h>         // tracing macros
#include <cyg/infra/cyg_ass.h>          // assertion macros

#include <cyg/hal/hal_arch.h>           // basic machine info
#include <cyg/hal/hal_intr.h>           // interrupt macros
#include <cyg/hal/hal_io.h>             // IO macros
#include <cyg/hal/hal_diag.h>
#include <cyg/hal/drv_api.h>
#include <cyg/hal/hal_if.h>             // interface API
#include <cyg/hal/hal_misc.h>           // Helper functions

//-----------------------------------------------------------------------------
// Make changes here
#include <pkgconf/hal_mips_rm7000_ocelot.h>  // board specifics

#define NS_SERIAL_A_BASE 0xbd000020
#define NS_SERIAL_A_IRQ  CYGNUM_HAL_INTERRUPT_UART1
#define NS_SERIAL_B_BASE 0xbd000000
#define NS_SERIAL_B_IRQ  CYGNUM_HAL_INTERRUPT_UART2

#define NS_CLOCK 20000000

// Fill in extra code as required
#define NS_EXTRA_INIT()                         \
    CYG_MACRO_START                             \
    CYG_MACRO_END

//-----------------------------------------------------------------------------


#define CYG_DEVICE_SERIAL_BAUD_MSB (((NS_CLOCK / (16*(CYGNUM_HAL_VIRTUAL_VECTOR_CHANNELS_DEFAULT_BAUD))) >> 8) & 0xff)
#define CYG_DEVICE_SERIAL_BAUD_LSB  ((NS_CLOCK / (16*(CYGNUM_HAL_VIRTUAL_VECTOR_CHANNELS_DEFAULT_BAUD))) & 0xff)

// Define the serial registers.
#define CYG_DEV_RBR 0x00   // receiver buffer register, read, dlab = 0
#define CYG_DEV_THR 0x00   // transmitter holding register, write, dlab = 0
#define CYG_DEV_DLL 0x00   // divisor latch (LS), read/write, dlab = 1
#define CYG_DEV_IER 0x04   // interrupt enable register, read/write, dlab = 0
#define CYG_DEV_DLM 0x04   // divisor latch (MS), read/write, dlab = 1
#define CYG_DEV_IIR 0x08   // interrupt identification register, read, dlab = 0
#define CYG_DEV_FCR 0x08   // fifo control register, write, dlab = 0
#define CYG_DEV_LCR 0x0C   // line control register, read/write
#define CYG_DEV_MCR 0x10   // modem control register, read/write
#define CYG_DEV_LSR 0x14   // line status register, read
#define CYG_DEV_MSR 0x18   // modem status register, read

// Interrupt Enable Register
#define SIO_IER_RCV 0x01
#define SIO_IER_XMT 0x02
#define SIO_IER_LS  0x04
#define SIO_IER_MS  0x08

// The line status register bits.
#define SIO_LSR_DR      0x01            // data ready
#define SIO_LSR_OE      0x02            // overrun error
#define SIO_LSR_PE      0x04            // parity error
#define SIO_LSR_FE      0x08            // framing error
#define SIO_LSR_BI      0x10            // break interrupt
#define SIO_LSR_THRE    0x20            // transmitter holding register empty
#define SIO_LSR_TEMT    0x40            // transmitter register empty
#define SIO_LSR_ERR     0x80            // any error condition

// The modem status register bits.
#define SIO_MSR_DCTS  0x01              // delta clear to send
#define SIO_MSR_DDSR  0x02              // delta data set ready
#define SIO_MSR_TERI  0x04              // trailing edge ring indicator
#define SIO_MSR_DDCD  0x08              // delta data carrier detect
#define SIO_MSR_CTS   0x10              // clear to send
#define SIO_MSR_DSR   0x20              // data set ready
#define SIO_MSR_RI    0x40              // ring indicator
#define SIO_MSR_DCD   0x80              // data carrier detect

// The line control register bits.
#define SIO_LCR_WLS0   0x01             // word length select bit 0
#define SIO_LCR_WLS1   0x02             // word length select bit 1
#define SIO_LCR_STB    0x04             // number of stop bits
#define SIO_LCR_PEN    0x08             // parity enable
#define SIO_LCR_EPS    0x10             // even parity select
#define SIO_LCR_SP     0x20             // stick parity
#define SIO_LCR_SB     0x40             // set break
#define SIO_LCR_DLAB   0x80             // divisor latch access bit

// Modem Control Register
#define SIO_MCR_DTR 0x01
#define SIO_MCR_RTS 0x02
#define SIO_MCR_INT 0x08   // Enable interrupts

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

//-----------------------------------------------------------------------------

static void
cyg_hal_plf_serial_init_channel(void* __ch_data)
{
    cyg_uint8* base = ((channel_data_t*)__ch_data)->base;
    cyg_uint8 lcr;

    // 8-1-no parity.
    HAL_WRITE_UINT8(base+CYG_DEV_LCR, SIO_LCR_WLS0 | SIO_LCR_WLS1);

    HAL_READ_UINT8(base+CYG_DEV_LCR, lcr);
    lcr |= SIO_LCR_DLAB;
    HAL_WRITE_UINT8(base+CYG_DEV_LCR, lcr);
    HAL_WRITE_UINT8(base+CYG_DEV_DLL, CYG_DEVICE_SERIAL_BAUD_LSB);
    HAL_WRITE_UINT8(base+CYG_DEV_DLM, CYG_DEVICE_SERIAL_BAUD_MSB);
    lcr &= ~SIO_LCR_DLAB;
    HAL_WRITE_UINT8(base+CYG_DEV_LCR, lcr);
    HAL_WRITE_UINT8(base+CYG_DEV_FCR, 0x07);  // Enable & clear FIFO

    NS_EXTRA_INIT();
}

void
cyg_hal_plf_serial_putc(void *__ch_data, char c)
{
    cyg_uint8* base = ((channel_data_t*)__ch_data)->base;
    cyg_uint8 lsr;
    CYGARC_HAL_SAVE_GP();

    do {
        HAL_READ_UINT8(base+CYG_DEV_LSR, lsr);
    } while ((lsr & SIO_LSR_THRE) == 0);

    HAL_WRITE_UINT8(base+CYG_DEV_THR, c);

    CYGARC_HAL_RESTORE_GP();
}

static cyg_bool
cyg_hal_plf_serial_getc_nonblock(void* __ch_data, cyg_uint8* ch)
{
    cyg_uint8* base = ((channel_data_t*)__ch_data)->base;
    cyg_uint8 lsr;

    HAL_READ_UINT8(base+CYG_DEV_LSR, lsr);
    if ((lsr & SIO_LSR_DR) == 0)
        return false;

    HAL_READ_UINT8(base+CYG_DEV_RBR, *ch);

    return true;
}

cyg_uint8
cyg_hal_plf_serial_getc(void* __ch_data)
{
    cyg_uint8 ch;
    CYGARC_HAL_SAVE_GP();

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

    CYGARC_HAL_RESTORE_GP();
    return ch;
}

static channel_data_t ns_ser_channels[2] = {
    { (cyg_uint8*)NS_SERIAL_A_BASE, 1000, NS_SERIAL_A_IRQ },
    { (cyg_uint8*)NS_SERIAL_B_BASE, 1000, NS_SERIAL_B_IRQ }
};

static void
cyg_hal_plf_serial_write(void* __ch_data, const cyg_uint8* __buf, 
                         cyg_uint32 __len)
{
    CYGARC_HAL_SAVE_GP();

    while(__len-- > 0)
        cyg_hal_plf_serial_putc(__ch_data, *__buf++);

    CYGARC_HAL_RESTORE_GP();
}

static void
cyg_hal_plf_serial_read(void* __ch_data, cyg_uint8* __buf, cyg_uint32 __len)
{
    CYGARC_HAL_SAVE_GP();

    while(__len-- > 0)
        *__buf++ = cyg_hal_plf_serial_getc(__ch_data);

    CYGARC_HAL_RESTORE_GP();
}

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

    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);
    }

    CYGARC_HAL_RESTORE_GP();
    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 = (channel_data_t*)__ch_data;
    int ret = 0;
    CYGARC_HAL_SAVE_GP();

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

        HAL_WRITE_UINT8(chan->base+CYG_DEV_IER, SIO_IER_RCV);
        HAL_WRITE_UINT8(chan->base+CYG_DEV_MCR, SIO_MCR_INT|SIO_MCR_DTR|SIO_MCR_RTS);

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

        HAL_WRITE_UINT8(chan->base+CYG_DEV_IER, 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);
    }        
    default:
        break;
    }
    CYGARC_HAL_RESTORE_GP();
    return ret;
}

static int
cyg_hal_plf_serial_isr(void *__ch_data, int* __ctrlc, 
                       CYG_ADDRWORD __vector, CYG_ADDRWORD __data)
{
    int res = 0;
    channel_data_t* chan = (channel_data_t*)__ch_data;
    char c;
    cyg_uint8 lsr;
    CYGARC_HAL_SAVE_GP();

    cyg_drv_interrupt_acknowledge(chan->isr_vector);

    *__ctrlc = 0;
    HAL_READ_UINT8(chan->base+CYG_DEV_LSR, lsr);
    if ( (lsr & SIO_LSR_DR) != 0 ) {

        HAL_READ_UINT8(chan->base+CYG_DEV_RBR, c);
        if( cyg_hal_is_break( &c , 1 ) )
            *__ctrlc = 1;

        res = CYG_ISR_HANDLED;
    }

    CYGARC_HAL_RESTORE_GP();
    return res;
}

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(ns_ser_channels[0].isr_vector);
    HAL_INTERRUPT_MASK(ns_ser_channels[1].isr_vector);

    // Init channels
    cyg_hal_plf_serial_init_channel(&ns_ser_channels[0]);
    cyg_hal_plf_serial_init_channel(&ns_ser_channels[1]);

    // 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, &ns_ser_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);

    // Set channel 1
    CYGACC_CALL_IF_SET_CONSOLE_COMM(1);
    comm = CYGACC_CALL_IF_CONSOLE_PROCS();
    CYGACC_COMM_IF_CH_DATA_SET(*comm, &ns_ser_channels[1]);
    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();
}

//-----------------------------------------------------------------------------

//=============================================================================
// Compatibility with older stubs
//=============================================================================

#ifndef CYGSEM_HAL_VIRTUAL_VECTOR_DIAG

#ifdef CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS
#include <cyg/hal/hal_stub.h>           // cyg_hal_gdb_interrupt
#endif

#if CYGNUM_HAL_VIRTUAL_VECTOR_CONSOLE_CHANNEL==0
// This is the base address of the A-channel
#define CYG_DEV_SERIAL_BASE      0x1d000020
#define CYG_DEVICE_SERIAL_INT    CYGNUM_HAL_INTERRUPT_SERIALA
#else
// This is the base address of the B-channel
#define CYG_DEV_SERIAL_BASE      0x1d000000
#define CYG_DEVICE_SERIAL_INT    CYGNUM_HAL_INTERRUPT_SERIALB
#endif

static channel_data_t ns_ser_channel = {
    (cyg_uint8*)CYG_DEV_SERIAL_BASE, 0, 0 
};

// Assumption: all diagnostic output must be GDB packetized unless this is a ROM (i.e.
// totally stand-alone) system.

#if defined(CYG_HAL_STARTUP_ROM) || !defined(CYGDBG_HAL_DIAG_TO_DEBUG_CHAN)
#define HAL_DIAG_USES_HARDWARE
#endif

#ifndef HAL_DIAG_USES_HARDWARE
#if (CYGNUM_HAL_VIRTUAL_VECTOR_CONSOLE_CHANNEL != CYGNUM_HAL_VIRTUAL_VECTOR_DEBUG_CHANNEL)
#define HAL_DIAG_USES_HARDWARE
#endif
#endif

#ifdef HAL_DIAG_USES_HARDWARE

void hal_diag_init(void)
{
    static int init = 0;
    char *msg = "\n\rARM eCos\n\r";

    if (init++) return;

    cyg_hal_plf_serial_init_channel(&ns_ser_channel);

    while (*msg) cyg_hal_plf_serial_putc(&ns_ser_channel, *msg++);
}

#ifdef DEBUG_DIAG
#if defined(CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS)
#define DIAG_BUFSIZE 32
#else
#define DIAG_BUFSIZE 2048
#endif
static char diag_buffer[DIAG_BUFSIZE];
static int diag_bp = 0;
#endif

void hal_diag_write_char(char c)
{
    hal_diag_init();

    cyg_hal_plf_serial_putc(&ns_ser_channel, c);

#ifdef DEBUG_DIAG
    diag_buffer[diag_bp++] = c;
    if (diag_bp == DIAG_BUFSIZE) diag_bp = 0;
#endif
}

void hal_diag_read_char(char *c)
{
    *c = cyg_hal_plf_serial_getc(&ns_ser_channel);
}

#else // HAL_DIAG relies on GDB

// Initialize diag port - assume GDB channel is already set up
void hal_diag_init(void)
{
    if (0) cyg_hal_plf_serial_init_channel(&ns_ser_channel); // avoid warning
}

// Actually send character down the wire
static void
hal_diag_write_char_serial(char c)
{
    hal_diag_init();

    cyg_hal_plf_serial_putc(&ns_ser_channel, c);
}

static bool
hal_diag_read_serial(char *c)
{
    long timeout = 1000000000;  // A long time...
    while (!cyg_hal_plf_serial_getc_nonblock(&ns_ser_channel, c))
        if (0 == --timeout) return false;

    return true;
}

void 
hal_diag_read_char(char *c)
{
    while (!hal_diag_read_serial(c)) ;
}

void 
hal_diag_write_char(char c)
{
    static char line[100];
    static int pos = 0;

    // No need to send CRs
    if( c == '\r' ) return;

    line[pos++] = c;

    if( c == '\n' || pos == sizeof(line) )
    {
        CYG_INTERRUPT_STATE old;

        // Disable interrupts. This prevents GDB trying to interrupt us
        // while we are in the middle of sending a packet. The serial
        // receive interrupt will be seen when we re-enable interrupts
        // later.
        
#ifdef CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS
        CYG_HAL_GDB_ENTER_CRITICAL_IO_REGION(old);
#else
        HAL_DISABLE_INTERRUPTS(old);
#endif

        while(1)
        {
            static char hex[] = "0123456789ABCDEF";
            cyg_uint8 csum = 0;
            int i;
            char c1;
        
            hal_diag_write_char_serial('$');
            hal_diag_write_char_serial('O');
            csum += 'O';
            for( i = 0; i < pos; i++ )
            {
                char ch = line[i];
                char h = hex[(ch>>4)&0xF];
                char l = hex[ch&0xF];
                hal_diag_write_char_serial(h);
                hal_diag_write_char_serial(l);
                csum += h;
                csum += l;
            }
            hal_diag_write_char_serial('#');
            hal_diag_write_char_serial(hex[(csum>>4)&0xF]);
            hal_diag_write_char_serial(hex[csum&0xF]);

            // Wait for the ACK character '+' from GDB here and handle
            // receiving a ^C instead.  This is the reason for this clause
            // being a loop.
            if (!hal_diag_read_serial(&c1))
                continue;   // No response - try sending packet again

            if( c1 == '+' )
                break;              // a good acknowledge

#ifdef CYGDBG_HAL_DEBUG_GDB_BREAK_SUPPORT
            cyg_drv_interrupt_acknowledge(CYG_DEVICE_SERIAL_INT);
            if( c1 == 3 ) {
                // Ctrl-C: breakpoint.
                cyg_hal_gdb_interrupt ((target_register_t)__builtin_return_address(0));
                break;
            }
#endif
            // otherwise, loop round again
        }
        
        pos = 0;

        // And re-enable interrupts
#ifdef CYGDBG_HAL_DEBUG_GDB_INCLUDE_STUBS
        CYG_HAL_GDB_LEAVE_CRITICAL_IO_REGION(old);
#else
        HAL_RESTORE_INTERRUPTS(old);
#endif
        
    }
}
#endif

#endif // CYGSEM_HAL_VIRTUAL_VECTOR_DIAG

//-----------------------------------------------------------------------------
// End of ns16552.c
