ser_16x5x.c

移植到WLIT项目的redboot源代码

//==========================================================================
//
//      io/serial/generic/16x5x/ser_16x5x.c
//
//      Generic 16x5x serial driver
//
//==========================================================================
//####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, jlarmour, jskov
// Date:         1999-02-04
// Purpose:      16x5x generic serial driver
// 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>

#include <cyg/hal/hal_io.h>

// Only compile driver if an inline file with driver details was selected.
#ifdef CYGDAT_IO_SERIAL_GENERIC_16X5X_INL

#ifndef CYGPRI_IO_SERIAL_GENERIC_16X5X_STEP
#define CYGPRI_IO_SERIAL_GENERIC_16X5X_STEP 1
#endif

#define SER_REG(_x_) ((_x_)*CYGPRI_IO_SERIAL_GENERIC_16X5X_STEP)

// Receive control Registers
#define REG_rhr SER_REG(0)    // Receive holding register
#define REG_isr SER_REG(2)    // Interrupt status register
#define REG_lsr SER_REG(5)    // Line status register
#define REG_msr SER_REG(6)    // Modem status register
#define REG_scr SER_REG(7)    // Scratch register

// Transmit control Registers
#define REG_thr SER_REG(0)    // Transmit holding register
#define REG_ier SER_REG(1)    // Interrupt enable register
#define REG_fcr SER_REG(2)    // FIFO control register
#define REG_lcr SER_REG(3)    // Line control register
#define REG_mcr SER_REG(4)    // Modem control register
#define REG_ldl SER_REG(0)    // LSB of baud rate
#define REG_mdl SER_REG(1)    // MSB of baud rate

// Interrupt Enable Register
#define IER_RCV 0x01
#define IER_XMT 0x02
#define IER_LS  0x04
#define IER_MS  0x08

// Line Control Register
#define LCR_WL5 0x00    // Word length
#define LCR_WL6 0x01
#define LCR_WL7 0x02
#define LCR_WL8 0x03
#define LCR_SB1 0x00    // Number of stop bits
#define LCR_SB1_5 0x04  // 1.5 -> only valid with 5 bit words
#define LCR_SB2 0x04
#define LCR_PN  0x00    // Parity mode - none
#define LCR_PE  0x0C    // Parity mode - even
#define LCR_PO  0x08    // Parity mode - odd
#define LCR_PM  0x28    // Forced "mark" parity
#define LCR_PS  0x38    // Forced "space" parity
#define LCR_DL  0x80    // Enable baud rate latch

// Line Status Register
#define LSR_RSR 0x01
#define LSR_OE  0x02
#define LSR_PE  0x04
#define LSR_FE  0x08
#define LSR_BI  0x10
#define LSR_THE 0x20
#define LSR_TEMT 0x40
#define LSR_FIE 0x80

// Modem Control Register
#define MCR_DTR 0x01
#define MCR_RTS 0x02
#define MCR_INT 0x08   // Enable interrupts

// Interrupt status Register
#define ISR_MS  0x00
#define ISR_nIP 0x01
#define ISR_Tx  0x02
#define ISR_LS  0x03
#define ISR_Rx  0x04
#define ISR_RxTO  0x0C

// Modem Status Register
#define MSR_DCTS 0x01
#define MSR_DDSR 0x02
#define MSR_TERI 0x04
#define MSR_DDCD 0x08
#define MSR_CTS  0x10
#define MSR_DSR  0x20
#define MSR_RI   0x40
#define MSR_CD   0x80

static unsigned char select_word_length[] = {
    LCR_WL5,    // 5 bits / word (char)
    LCR_WL6,
    LCR_WL7,
    LCR_WL8
};

static unsigned char select_stop_bits[] = {
    0,
    LCR_SB1,    // 1 stop bit
    LCR_SB1_5,  // 1.5 stop bit
    LCR_SB2     // 2 stop bits
};

static unsigned char select_parity[] = {
    LCR_PN,     // No parity
    LCR_PE,     // Even parity
    LCR_PO,     // Odd parity
    LCR_PM,     // Mark parity
    LCR_PS,     // Space parity
};

// selec_baud[] must be define by the client

typedef struct pc_serial_info {
    cyg_addrword_t base;
    int            int_num;
    cyg_interrupt  serial_interrupt;
    cyg_handle_t   serial_interrupt_handle;
} pc_serial_info;

static bool pc_serial_init(struct cyg_devtab_entry *tab);
static bool pc_serial_putc(serial_channel *chan, unsigned char c);
static Cyg_ErrNo pc_serial_lookup(struct cyg_devtab_entry **tab, 
                                  struct cyg_devtab_entry *sub_tab,
                                  const char *name);
static unsigned char pc_serial_getc(serial_channel *chan);
static Cyg_ErrNo pc_serial_set_config(serial_channel *chan, cyg_uint32 key,
                                      const void *xbuf, cyg_uint32 *len);
static void pc_serial_start_xmit(serial_channel *chan);
static void pc_serial_stop_xmit(serial_channel *chan);

static cyg_uint32 pc_serial_ISR(cyg_vector_t vector, cyg_addrword_t data);
static void       pc_serial_DSR(cyg_vector_t vector, cyg_ucount32 count,
                                cyg_addrword_t data);

static SERIAL_FUNS(pc_serial_funs, 
                   pc_serial_putc, 
                   pc_serial_getc,
                   pc_serial_set_config,
                   pc_serial_start_xmit,
                   pc_serial_stop_xmit
    );

#include CYGDAT_IO_SERIAL_GENERIC_16X5X_INL

// Internal function to actually configure the hardware to desired
// baud rate, etc.
static bool
serial_config_port(serial_channel *chan, 
                   cyg_serial_info_t *new_config, bool init)
{
    pc_serial_info *ser_chan = (pc_serial_info *)chan->dev_priv;
    cyg_addrword_t base = ser_chan->base;
    unsigned short baud_divisor = select_baud[new_config->baud];
    unsigned char _lcr, _ier;
    if (baud_divisor == 0) return false;  // Invalid configuration

    // Disable port interrupts while changing hardware
    HAL_READ_UINT8(base+REG_ier, _ier);
    HAL_WRITE_UINT8(base+REG_ier, 0);

    _lcr = select_word_length[new_config->word_length - CYGNUM_SERIAL_WORD_LENGTH_5] | 
        select_stop_bits[new_config->stop] |
        select_parity[new_config->parity];
    HAL_WRITE_UINT8(base+REG_lcr, _lcr | LCR_DL);
    HAL_WRITE_UINT8(base+REG_mdl, baud_divisor >> 8);
    HAL_WRITE_UINT8(base+REG_ldl, baud_divisor & 0xFF);
    HAL_WRITE_UINT8(base+REG_lcr, _lcr);
    if (init) {
        HAL_WRITE_UINT8(base+REG_fcr, 0x07);  // Enable and clear FIFO
        if (chan->out_cbuf.len != 0) {
            _ier = IER_RCV;
        } else {
            _ier = 0;
        }
        // Master interrupt enable
        HAL_WRITE_UINT8(base+REG_mcr, MCR_INT|MCR_DTR|MCR_RTS);
    }
#ifdef CYGOPT_IO_SERIAL_SUPPORT_LINE_STATUS
    _ier |= (IER_LS|IER_MS);
#endif
    HAL_WRITE_UINT8(base+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 
pc_serial_init(struct cyg_devtab_entry *tab)
{
    serial_channel *chan = (serial_channel *)tab->priv;
    pc_serial_info *ser_chan = (pc_serial_info *)chan->dev_priv;
#ifdef CYGDBG_IO_INIT
    diag_printf("16x5x SERIAL init - dev: %x.%d\n", 
                ser_chan->base, ser_chan->int_num);
#endif
    // Really only required for interrupt driven devices
    (chan->callbacks->serial_init)(chan);

    if (chan->out_cbuf.len != 0) {
        cyg_drv_interrupt_create(ser_chan->int_num,
                                 99,
                                 (cyg_addrword_t)chan,
                                 pc_serial_ISR,
                                 pc_serial_DSR,
                                 &ser_chan->serial_interrupt_handle,
                                 &ser_chan->serial_interrupt);
        cyg_drv_interrupt_attach(ser_chan->serial_interrupt_handle);