Subversion Repositories openrisc_2011-10-31

//==========================================================================

//

//      io/serial/powerpc/quicc_smc_serial.c

//

//      PowerPC QUICC (SMC) 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.

// Copyright (C) 2003 Gary Thomas

//

// 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):    gthomas

// Contributors: gthomas

// Date:         1999-06-20

// Purpose:      QUICC SMC 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>

#include <cyg/hal/hal_cache.h>

#include <cyg/hal/quicc/ppc8xx.h>

#include CYGBLD_HAL_PLATFORM_H

#ifdef CYGPKG_IO_SERIAL_POWERPC_QUICC_SMC

// macro for aligning buffers to cache lines

#define ALIGN_TO_CACHELINES(b) ((cyg_uint8 *)(((CYG_ADDRESS)(b) + (HAL_DCACHE_LINE_SIZE-1)) & ~(HAL_DCACHE_LINE_SIZE-1)))

// Buffer descriptor control bits

#define QUICC_BD_CTL_Ready 0x8000  // Buffer contains data (tx) or is empty (rx)

#define QUICC_BD_CTL_Wrap  0x2000  // Last buffer in list

#define QUICC_BD_CTL_Int   0x1000  // Generate interrupt when empty (tx) or full (rx)

#define QUICC_BD_CTL_MASK  0xB000  // User settable bits

// SMC Mode Register

#define QUICC_SMCMR_CLEN(n)   ((n+1)<<11)   // Character length

#define QUICC_SMCMR_SB(n)     ((n-1)<<10)   // Stop bits (1 or 2)

#define QUICC_SMCMR_PE(n)     (n<<9)        // Parity enable (0=disable, 1=enable)

#define QUICC_SMCMR_PM(n)     (n<<8)        // Parity mode (0=odd, 1=even)

#define QUICC_SMCMR_UART      (2<<4)        // UART mode

#define QUICC_SMCMR_TEN       (1<<1)        // Enable transmitter

#define QUICC_SMCMR_REN       (1<<0)        // Enable receiver

// SMC Events (interrupts)

#define QUICC_SMCE_BRK 0x10  // Break received

#define QUICC_SMCE_BSY 0x04  // Busy - receive buffer overrun

#define QUICC_SMCE_TX  0x02  // Tx interrupt

#define QUICC_SMCE_RX  0x01  // Rx interrupt

// SMC Commands

#define QUICC_SMC_CMD_InitTxRx  (0<<8)

#define QUICC_SMC_CMD_InitTx    (1<<8)

#define QUICC_SMC_CMD_InitRx    (2<<8)

#define QUICC_SMC_CMD_StopTx    (4<<8)

#define QUICC_SMC_CMD_RestartTx (6<<8)

#define QUICC_SMC_CMD_Reset     0x8000

#define QUICC_SMC_CMD_Go        0x0001

#include "quicc_smc_serial.h"

typedef struct quicc_smc_serial_info {

    CYG_ADDRWORD          channel;                   // Which channel SMC1/SMC2

    CYG_WORD              int_num;                   // Interrupt number

    cyg_uint32            *brg;                      // Which baud rate generator

    volatile struct smc_uart_pram  *pram;            // Parameter RAM pointer

    volatile struct smc_regs       *ctl;             // SMC control registers

    volatile struct cp_bufdesc     *txbd, *rxbd;     // Next Tx,Rx descriptor to use

    struct cp_bufdesc     *tbase, *rbase;            // First Tx,Rx descriptor

    int                   txsize, rxsize;            // Length of individual buffers

    cyg_interrupt         serial_interrupt;

    cyg_handle_t          serial_interrupt_handle;

} quicc_smc_serial_info;

static bool quicc_smc_serial_init(struct cyg_devtab_entry *tab);

static bool quicc_smc_serial_putc(serial_channel *chan, unsigned char c);

static Cyg_ErrNo quicc_smc_serial_lookup(struct cyg_devtab_entry **tab,

                                   struct cyg_devtab_entry *sub_tab,

                                   const char *name);

static unsigned char quicc_smc_serial_getc(serial_channel *chan);

static Cyg_ErrNo quicc_smc_serial_set_config(serial_channel *chan,

                                             cyg_uint32 key, const void *xbuf,

                                             cyg_uint32 *len);

static void quicc_smc_serial_start_xmit(serial_channel *chan);

static void quicc_smc_serial_stop_xmit(serial_channel *chan);

static cyg_uint32 quicc_smc_serial_ISR(cyg_vector_t vector, cyg_addrword_t data);

static void       quicc_smc_serial_DSR(cyg_vector_t vector, cyg_ucount32 count, cyg_addrword_t data);

static SERIAL_FUNS(quicc_smc_serial_funs,

                   quicc_smc_serial_putc,

                   quicc_smc_serial_getc,

                   quicc_smc_serial_set_config,

                   quicc_smc_serial_start_xmit,

                   quicc_smc_serial_stop_xmit

    );

#ifdef CYGPKG_IO_SERIAL_POWERPC_QUICC_SMC_SMC1

static quicc_smc_serial_info quicc_smc_serial_info1 = {

    0x90,                         // Channel indicator

    CYGNUM_HAL_INTERRUPT_CPM_SMC1 // interrupt

};

#if CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_BUFSIZE > 0

static unsigned char quicc_smc_serial_out_buf1[CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_BUFSIZE];

static unsigned char quicc_smc_serial_in_buf1[CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_BUFSIZE];

static SERIAL_CHANNEL_USING_INTERRUPTS(quicc_smc_serial_channel1,

                                       quicc_smc_serial_funs,

                                       quicc_smc_serial_info1,

                                       CYG_SERIAL_BAUD_RATE(CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_BAUD),

                                       CYG_SERIAL_STOP_DEFAULT,

                                       CYG_SERIAL_PARITY_DEFAULT,

                                       CYG_SERIAL_WORD_LENGTH_DEFAULT,

                                       CYG_SERIAL_FLAGS_DEFAULT,

                                       &quicc_smc_serial_out_buf1[0], sizeof(quicc_smc_serial_out_buf1),

                                       &quicc_smc_serial_in_buf1[0], sizeof(quicc_smc_serial_in_buf1)

    );

#else

static SERIAL_CHANNEL(quicc_smc_serial_channel1,

                      quicc_smc_serial_funs,

                      quicc_smc_serial_info1,

                      CYG_SERIAL_BAUD_RATE(CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_BAUD),

                      CYG_SERIAL_STOP_DEFAULT,

                      CYG_SERIAL_PARITY_DEFAULT,

                      CYG_SERIAL_WORD_LENGTH_DEFAULT,

                      CYG_SERIAL_FLAGS_DEFAULT

    );

#endif

static unsigned char quicc_smc1_txbuf[CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_TxNUM][CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_TxSIZE + HAL_DCACHE_LINE_SIZE-1];

static unsigned char quicc_smc1_rxbuf[CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_RxNUM][CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_RxSIZE + HAL_DCACHE_LINE_SIZE-1];

DEVTAB_ENTRY(quicc_smc_serial_io1,

             CYGDAT_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_NAME,

             0,                     // Does not depend on a lower level interface

             &cyg_io_serial_devio,

             quicc_smc_serial_init,

             quicc_smc_serial_lookup,     // Serial driver may need initializing

             &quicc_smc_serial_channel1

    );

#endif //  CYGPKG_IO_SERIAL_POWERPC_QUICC_SMC_SMC1

#ifdef CYGPKG_IO_SERIAL_POWERPC_QUICC_SMC_SMC2

static quicc_smc_serial_info quicc_smc_serial_info2 = {

    0xD0,                             // Channel indicator

    CYGNUM_HAL_INTERRUPT_CPM_SMC2_PIP // interrupt

};

#if CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_BUFSIZE > 0

static unsigned char quicc_smc_serial_out_buf2[CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_BUFSIZE];

static unsigned char quicc_smc_serial_in_buf2[CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_BUFSIZE];

static SERIAL_CHANNEL_USING_INTERRUPTS(quicc_smc_serial_channel2,

                                       quicc_smc_serial_funs,

                                       quicc_smc_serial_info2,

                                       CYG_SERIAL_BAUD_RATE(CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_BAUD),

                                       CYG_SERIAL_STOP_DEFAULT,

                                       CYG_SERIAL_PARITY_DEFAULT,

                                       CYG_SERIAL_WORD_LENGTH_DEFAULT,

                                       CYG_SERIAL_FLAGS_DEFAULT,

                                       &quicc_smc_serial_out_buf2[0], sizeof(quicc_smc_serial_out_buf2),

                                       &quicc_smc_serial_in_buf2[0], sizeof(quicc_smc_serial_in_buf2)

    );

#else

static SERIAL_CHANNEL(quicc_smc_serial_channel2,

                      quicc_smc_serial_funs,

                      quicc_smc_serial_info2,

                      CYG_SERIAL_BAUD_RATE(CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_BAUD),

                      CYG_SERIAL_STOP_DEFAULT,

                      CYG_SERIAL_PARITY_DEFAULT,

                      CYG_SERIAL_WORD_LENGTH_DEFAULT,

                      CYG_SERIAL_FLAGS_DEFAULT

    );

#endif

static unsigned char quicc_smc2_txbuf[CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_TxNUM][CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_TxSIZE + HAL_DCACHE_LINE_SIZE-1];

static unsigned char quicc_smc2_rxbuf[CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_RxNUM][CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_RxSIZE + HAL_DCACHE_LINE_SIZE-1];

DEVTAB_ENTRY(quicc_smc_serial_io2,

             CYGDAT_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_NAME,

             0,                     // Does not depend on a lower level interface

             &cyg_io_serial_devio,

             quicc_smc_serial_init,

             quicc_smc_serial_lookup,     // Serial driver may need initializing

             &quicc_smc_serial_channel2

    );

#endif //  CYGPKG_IO_SERIAL_POWERPC_QUICC_SMC_SMC2

#ifdef CYGDBG_DIAG_BUF

extern int enable_diag_uart;

#endif // CYGDBG_DIAG_BUF

// Internal function to actually configure the hardware to desired baud rate, etc.

static bool

quicc_smc_serial_config_port(serial_channel *chan, cyg_serial_info_t *new_config, bool init)

{

    quicc_smc_serial_info *smc_chan = (quicc_smc_serial_info *)chan->dev_priv;

    unsigned int baud_divisor = select_baud[new_config->baud];

    cyg_uint32 _lcr;

    EPPC *eppc = eppc_base();

    if (baud_divisor == 0) return false;

    // Disable channel during setup

    smc_chan->ctl->smc_smcmr = QUICC_SMCMR_UART;  // Disabled, UART mode

    // 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];

    // Stop transmitter while changing baud rate

    eppc->cp_cr = smc_chan->channel | QUICC_SMC_CMD_Go | QUICC_SMC_CMD_StopTx;

    // Set baud rate generator

    *smc_chan->brg = 0x10000 | (UART_BITRATE(baud_divisor)<<1);

#ifdef XX_CYGDBG_DIAG_BUF

        enable_diag_uart = 0;

        diag_printf("Set BAUD RATE[%x], %d = %x, tstate = %x\n", smc_chan->brg, baud_divisor, *smc_chan->brg, smc_chan->pram->tstate);

        enable_diag_uart = 1;

#endif // CYGDBG_DIAG_BUF

    // Enable channel with new configuration

    smc_chan->ctl->smc_smcmr = QUICC_SMCMR_UART|QUICC_SMCMR_TEN|QUICC_SMCMR_REN|_lcr;

    eppc->cp_cr = smc_chan->channel | QUICC_SMC_CMD_Go | QUICC_SMC_CMD_RestartTx;

    if (new_config != &chan->config) {

        chan->config = *new_config;

    }

    return true;

}

// Function to set up internal tables for device.

static void

quicc_smc_serial_init_info(quicc_smc_serial_info *smc_chan,

                           volatile struct smc_uart_pram *uart_pram,

                           volatile struct smc_regs *ctl,

                           int TxBD, int TxNUM, int TxSIZE,

                           cyg_uint8 *TxBUF,

                           int RxBD, int RxNUM, int RxSIZE,

                           cyg_uint8 *RxBUF,

                           int portBmask,

                           int BRG, int SIpos)

{

    EPPC *eppc = eppc_base();

    struct cp_bufdesc *txbd, *rxbd;

    cyg_uint32 simode = 0;

    int i;

    // Disable channel during setup

    ctl->smc_smcmr = QUICC_SMCMR_UART;  // Disabled, UART mode

    smc_chan->pram = uart_pram;

    smc_chan->ctl = ctl;

    /*

     *  SDMA & LCD bus request level 5

     *  (Section 16.10.2.1)

     */

    eppc->dma_sdcr = 1;

    switch (BRG) {

    case 1:

        smc_chan->brg = (cyg_uint32 *)&eppc->brgc1;

        simode = 0;

        break;

    case 2:

        smc_chan->brg = (cyg_uint32 *)&eppc->brgc2;

        simode = 1;

        break;

    case 3:

        smc_chan->brg = (cyg_uint32 *)&eppc->brgc3;

        simode = 2;

        break;

    case 4:

        smc_chan->brg = (cyg_uint32 *)&eppc->brgc4;

        simode = 3;

        break;

    }

    // NMSI mode, BRGn to SMCm  (Section 16.12.5.2)

    eppc->si_simode = (eppc->si_simode & ~(0xF<<SIpos)) | (simode<<SIpos);

    /*

     *  Set up the PortB pins for UART operation.

     *  Set PAR and DIR to allow SMCTXDx and SMRXDx

     *  (Table 16-39)

     */

    eppc->pip_pbpar |= portBmask;

    eppc->pip_pbdir &= ~portBmask;

    /*

     *  SDMA & LCD bus request level 5

     *  (Section 16.10.2.1)

     */

    eppc->dma_sdcr = 1;

    /*

     *  Set Rx and Tx function code

     *  (Section 16.15.4.2)

     */

    uart_pram->rfcr = 0x18;

    uart_pram->tfcr = 0x18;

    /*

     *  Set pointers to buffer descriptors.

     *  (Sections 16.15.4.1, 16.15.7.12, and 16.15.7.13)

     */

    uart_pram->rbase = RxBD;

    uart_pram->tbase = TxBD;

    /* tx and rx buffer descriptors */

    txbd = (struct cp_bufdesc *)((char *)eppc + TxBD);

    rxbd = (struct cp_bufdesc *)((char *)eppc + RxBD);

    smc_chan->txbd = txbd;

    smc_chan->tbase = txbd;

    smc_chan->txsize = TxSIZE;

    smc_chan->rxbd = rxbd;

    smc_chan->rbase = rxbd;

    smc_chan->rxsize = RxSIZE;

    /* max receive buffer length */

    uart_pram->mrblr = RxSIZE;

    /* set max_idle feature - generate interrupt after 4 chars idle period */

    uart_pram->max_idl = 4;

    /* no last brk char received */

    uart_pram->brkln = 0;

    /* no break condition occurred */

    uart_pram->brkec = 0;

    /* 1 break char sent on top XMIT */

    uart_pram->brkcr = 1;

    /* setup RX buffer descriptors */

    for (i = 0;  i < RxNUM;  i++) {

        rxbd->length = 0;

        rxbd->buffer = RxBUF;

        rxbd->ctrl   = QUICC_BD_CTL_Ready | QUICC_BD_CTL_Int;

        if (i == (RxNUM-1)) rxbd->ctrl |= QUICC_BD_CTL_Wrap;  // Last buffer

        RxBUF += RxSIZE;

        rxbd++;

    }

    /* setup TX buffer descriptors */

    for (i = 0;  i < TxNUM;  i++) {

        txbd->length = 0;

        txbd->buffer = TxBUF;

        txbd->ctrl   = 0;

        if (i == (TxNUM-1)) txbd->ctrl |= QUICC_BD_CTL_Wrap;  // Last buffer

        TxBUF += TxSIZE;

        txbd++;

    }

    /*

     *  Reset Rx & Tx params

     */

    eppc->cp_cr = smc_chan->channel | QUICC_SMC_CMD_Go | QUICC_SMC_CMD_InitTxRx;

    /*

     *  Clear any previous events. Enable interrupts.

     *  (Section 16.15.7.14 and 16.15.7.15)

     */

    ctl->smc_smce = 0xFF;

    ctl->smc_smcm = QUICC_SMCE_BSY|QUICC_SMCE_TX|QUICC_SMCE_RX;

}

// Function to initialize the device.  Called at bootstrap time.

static bool

quicc_smc_serial_init(struct cyg_devtab_entry *tab)

{

    serial_channel *chan = (serial_channel *)tab->priv;

    quicc_smc_serial_info *smc_chan = (quicc_smc_serial_info *)chan->dev_priv;

    volatile EPPC *eppc = (volatile EPPC *)eppc_base();

    int TxBD, RxBD;

    static int first_init = 1;

    int cache_state;

    HAL_DCACHE_IS_ENABLED(cache_state);

    HAL_DCACHE_SYNC();

    HAL_DCACHE_DISABLE();

#ifdef CYGDBG_IO_INIT

    diag_printf("QUICC_SMC SERIAL init - dev: %x.%d\n", smc_chan->channel, smc_chan->int_num);

#endif

    if (first_init) {

        // Set up tables since many fields are dynamic [computed at runtime]

        first_init = 0;

#ifdef CYGPKG_IO_SERIAL_POWERPC_QUICC_SMC_SMC1

        eppc->cp_cr = QUICC_SMC_CMD_Reset | QUICC_SMC_CMD_Go;  // Totally reset CP

        while (eppc->cp_cr & QUICC_SMC_CMD_Reset) ;

        TxBD = _mpc8xx_allocBd(sizeof(struct cp_bufdesc)*CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_TxNUM);

        RxBD = _mpc8xx_allocBd(sizeof(struct cp_bufdesc)*CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_RxNUM);

        quicc_smc_serial_init_info(&quicc_smc_serial_info1,

                                   &eppc->pram[2].scc.pothers.smc_modem.psmc.u, // PRAM

                                   &eppc->smc_regs[0], // Control registers

                                   TxBD,

                                   CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_TxNUM,

                                   CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_TxSIZE,

                                   ALIGN_TO_CACHELINES(&quicc_smc1_txbuf[0][0]),

                                   RxBD,

                                   CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_RxNUM,

                                   CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_RxSIZE,

                                   ALIGN_TO_CACHELINES(&quicc_smc1_rxbuf[0][0]),

                                   0xC0, // PortB mask

                                   CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_BRG,

                                   12  // SI mask position

            );

#else

#ifdef CYGPKG_HAL_POWERPC_MBX

        // Ensure the SMC1 side is initialized first and use shared mem

        // above where it plays:

        diag_init();    // (pull in constructor that inits diag channel)

        TxBD = 0x2830;  // Note: this should be inferred from the chip state

#else

        // there is no diag device wanting to use the QUICC, so prepare it

        // for SMC2 use only.

        eppc->cp_cr = QUICC_SMC_CMD_Reset | QUICC_SMC_CMD_Go;  // Totally reset CP

        while (eppc->cp_cr & QUICC_SMC_CMD_Reset) ;

        TxBD = 0x2800;  // Note: this should be configurable

#endif        

#endif

#ifdef CYGPKG_IO_SERIAL_POWERPC_QUICC_SMC_SMC2

        TxBD = _mpc8xx_allocBd(sizeof(struct cp_bufdesc)*CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_TxNUM);

        RxBD = _mpc8xx_allocBd(sizeof(struct cp_bufdesc)*CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_RxNUM);

        quicc_smc_serial_init_info(&quicc_smc_serial_info2,

                                   &eppc->pram[3].scc.pothers.smc_modem.psmc.u, // PRAM

                                   &eppc->smc_regs[1], // Control registers

                                   TxBD,

                                   CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_TxNUM,

                                   CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_TxSIZE,

                                   ALIGN_TO_CACHELINES(&quicc_smc2_txbuf[0][0]),

                                   RxBD,

                                   CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_RxNUM,

                                   CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_RxSIZE,

                                   ALIGN_TO_CACHELINES(&quicc_smc2_rxbuf[0][0]),

                                   0xC00, // PortB mask

                                   CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC2_BRG,

                                   28  // SI mask position

            );

#endif

    }

    (chan->callbacks->serial_init)(chan);  // Really only required for interrupt driven devices

    if (chan->out_cbuf.len != 0) {

        cyg_drv_interrupt_create(smc_chan->int_num,

                                 CYGARC_SIU_PRIORITY_HIGH, // Priority - unused (but asserted)

                                 (cyg_addrword_t)chan,   //  Data item passed to interrupt handler

                                 quicc_smc_serial_ISR,

                                 quicc_smc_serial_DSR,

                                 &smc_chan->serial_interrupt_handle,

                                 &smc_chan->serial_interrupt);

        cyg_drv_interrupt_attach(smc_chan->serial_interrupt_handle);

        cyg_drv_interrupt_unmask(smc_chan->int_num);

    }

    quicc_smc_serial_config_port(chan, &chan->config, true);

    if (cache_state)

        HAL_DCACHE_ENABLE();

    return true;

}

// This routine is called when the device is "looked" up (i.e. attached)

static Cyg_ErrNo

quicc_smc_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;

}

// Force the current transmit buffer to be sent

static void

quicc_smc_serial_flush(quicc_smc_serial_info *smc_chan)

{

    volatile struct cp_bufdesc *txbd = smc_chan->txbd;

    int cache_state;

    HAL_DCACHE_IS_ENABLED(cache_state);

    if (cache_state) {

      HAL_DCACHE_FLUSH(txbd->buffer, smc_chan->txsize);

    }

    if ((txbd->length > 0) &&

        ((txbd->ctrl & (QUICC_BD_CTL_Ready|QUICC_BD_CTL_Int)) == 0)) {

        txbd->ctrl |= QUICC_BD_CTL_Ready|QUICC_BD_CTL_Int;  // Signal buffer ready

        if (txbd->ctrl & QUICC_BD_CTL_Wrap) {

            txbd = smc_chan->tbase;

        } else {

            txbd++;

        }

        smc_chan->txbd = txbd;

    }

}

// Send a character to the device output buffer.

// Return 'true' if character is sent to device

static bool

quicc_smc_serial_putc(serial_channel *chan, unsigned char c)

{

    quicc_smc_serial_info *smc_chan = (quicc_smc_serial_info *)chan->dev_priv;

    volatile struct cp_bufdesc *txbd, *txfirst;

    EPPC *eppc = eppc_base();

    bool res;

    cyg_drv_dsr_lock();  // Avoid race condition testing pointers

    txbd = (struct cp_bufdesc *)((char *)eppc + smc_chan->pram->tbptr);

    txfirst = txbd;

    // Scan for a non-busy buffer

    while (txbd->ctrl & QUICC_BD_CTL_Ready) {

        // This buffer is busy, move to next one

        if (txbd->ctrl & QUICC_BD_CTL_Wrap) {

            txbd = smc_chan->tbase;

        } else {

            txbd++;

        }

        if (txbd == txfirst) break;  // Went all the way around

    }

    smc_chan->txbd = txbd;

    if ((txbd->ctrl & (QUICC_BD_CTL_Ready|QUICC_BD_CTL_Int)) == 0) {

        // Transmit buffer is not full/busy

        txbd->buffer[txbd->length++] = c;

        if (txbd->length == smc_chan->txsize) {

            // This buffer is now full, tell SMC to start processing it

            quicc_smc_serial_flush(smc_chan);

        }

        res = true;

    } else {

        // No space

        res = false;

    }

    cyg_drv_dsr_unlock();

    return res;

}

// Fetch a character from the device input buffer, waiting if necessary

static unsigned char

quicc_smc_serial_getc(serial_channel *chan)

{

    unsigned char c;

    quicc_smc_serial_info *smc_chan = (quicc_smc_serial_info *)chan->dev_priv;

    volatile struct cp_bufdesc *rxbd = smc_chan->rxbd;

    while ((rxbd->ctrl & QUICC_BD_CTL_Ready) != 0) ;

    c = rxbd->buffer[0];

    rxbd->length = smc_chan->rxsize;

    rxbd->ctrl |= QUICC_BD_CTL_Ready;

    if (rxbd->ctrl & QUICC_BD_CTL_Wrap) {

        rxbd = smc_chan->rbase;

    } else {

        rxbd++;

    }

    smc_chan->rxbd = (struct cp_bufdesc *)rxbd;

    return c;

}

// Set up the device characteristics; baud rate, etc.

static Cyg_ErrNo

quicc_smc_serial_set_config(serial_channel *chan, cyg_uint32 key,

                            const void *xbuf, cyg_uint32 *len)

{

    switch (key) {

    case CYG_IO_SET_CONFIG_SERIAL_INFO:

      {

          // FIXME - The documentation says that you can't change the baud rate

          // again until at least two BRG input clocks have occurred.

        cyg_serial_info_t *config = (cyg_serial_info_t *)xbuf;

        if ( *len < sizeof(cyg_serial_info_t) ) {

            return -EINVAL;

        }

        *len = sizeof(cyg_serial_info_t);

        if ( true != quicc_smc_serial_config_port(chan, config, false) )

            return -EINVAL;

      }

      break;

    default:

        return -EINVAL;

    }

    return ENOERR;

}

// Enable the transmitter (interrupt) on the device

static void

quicc_smc_serial_start_xmit(serial_channel *chan)

{

    quicc_smc_serial_info *smc_chan = (quicc_smc_serial_info *)chan->dev_priv;

    cyg_drv_dsr_lock();

    if (smc_chan->txbd->length == 0) {

        // See if there is anything to put in this buffer, just to get it going

        (chan->callbacks->xmt_char)(chan);

    }

    if (smc_chan->txbd->length != 0) {

        // Make sure it gets started

        quicc_smc_serial_flush(smc_chan);

    }

    cyg_drv_dsr_unlock();

}

// Disable the transmitter on the device

static void

quicc_smc_serial_stop_xmit(serial_channel *chan)

{

    quicc_smc_serial_info *smc_chan = (quicc_smc_serial_info *)chan->dev_priv;

    // If anything is in the last buffer, need to get it started

    if (smc_chan->txbd->length != 0) {

        quicc_smc_serial_flush(smc_chan);

    }

}

// Serial I/O - low level interrupt handler (ISR)

static cyg_uint32

quicc_smc_serial_ISR(cyg_vector_t vector, cyg_addrword_t data)

{

    serial_channel *chan = (serial_channel *)data;

    quicc_smc_serial_info *smc_chan = (quicc_smc_serial_info *)chan->dev_priv;

    cyg_drv_interrupt_mask(smc_chan->int_num);

    return (CYG_ISR_HANDLED|CYG_ISR_CALL_DSR);  // Cause DSR to be run

}

// Serial I/O - high level interrupt handler (DSR)

static void

quicc_smc_serial_DSR(cyg_vector_t vector, cyg_ucount32 count, cyg_addrword_t data)

{

    serial_channel *chan = (serial_channel *)data;

    quicc_smc_serial_info *smc_chan = (quicc_smc_serial_info *)chan->dev_priv;

    volatile struct smc_regs *ctl = smc_chan->ctl;

    volatile struct cp_bufdesc *txbd;

    volatile struct cp_bufdesc *rxbd = smc_chan->rxbd;

    struct cp_bufdesc *rxlast;

    int i, cache_state;

#ifdef CYGDBG_DIAG_BUF

    int _time, _stime;

    externC cyg_tick_count_t cyg_current_time(void);

    cyg_drv_isr_lock();

    enable_diag_uart = 0;

    HAL_CLOCK_READ(&_time);

    _stime = (int)cyg_current_time();

    diag_printf("DSR start - CE: %x, time: %x.%x\n", ctl->smc_smce, _stime, _time);

    enable_diag_uart = 1;

#endif // CYGDBG_DIAG_BUF

    if (ctl->smc_smce & QUICC_SMCE_TX) {

#ifdef XX_CYGDBG_DIAG_BUF

        enable_diag_uart = 0;

        txbd = smc_chan->tbase;

        for (i = 0;  i < CYGNUM_IO_SERIAL_POWERPC_QUICC_SMC_SMC1_TxNUM;  i++, txbd++) {

            diag_printf("Tx BD: %x, length: %d, ctl: %x\n", txbd, txbd->length, txbd->ctrl);

        }

        enable_diag_uart = 1;

#endif // CYGDBG_DIAG_BUF

        // Transmit interrupt

        ctl->smc_smce = QUICC_SMCE_TX;  // Reset interrupt state;

        txbd = smc_chan->tbase;  // First buffer

        while (true) {

            if ((txbd->ctrl & (QUICC_BD_CTL_Ready|QUICC_BD_CTL_Int)) == QUICC_BD_CTL_Int) {

#ifdef XX_CYGDBG_DIAG_BUF

                enable_diag_uart = 0;

                HAL_CLOCK_READ(&_time);