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

//####UNSUPPORTEDBEGIN####

//

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

// This source file has been contributed to eCos/Red Hat. It may have been

// changed slightly to provide an interface consistent with those of other 

// files.

//

// The functionality and contents of this file is supplied "AS IS"

// without any form of support and will not necessarily be kept up

// to date by Red Hat.

//

// The style of programming used in this file may not comply with the

// eCos programming guidelines. Please do not use as a base for other

// files.

//

// All inquiries about this file, or the functionality provided by it,

// should be directed to the 'ecos-discuss' mailing list (see

// http://sourceware.cygnus.com/ecos/intouch.html for details).

//

// Contributed by: Kevin Hester <khester@opticworks.com>

// Maintained by:  <Unmaintained>

// See also:

//   Motorola's "Example Software Initializing the SMC as a UART" package 

//   (smc2.zip) at:

//    http://www.mot.com/SPS/RISC/netcomm/tools/index.html#MPC860_table

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

//

//####UNSUPPORTEDEND####

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

/*-------------------------------------------------------------------------

* FILENAME:  smc2.c

*

* DESCRIPTION:

*

*   The code in this module provides echo capability on SMC2. It's

*   intent is to provide the beginnings of a debug port that is

*   mostly compiler independent. If an ASCII terminal is connected

*   at 9600,N,8,1 on Port 2 (PB3) on the ADS board with no hardware

*   control, characters typed on the keyboard will be received by

*   SMC2 and echoed back out the RS232 port to the ASCII terminal.

*   This function was designed and tested on an ADS860

*   development board. Note that if a different baud rate is

*   required, there is a header file on the netcomm website under

*   the General Software category that is labelled "Asynchronous

*   Baud Rate Tables".

*

* REFERENCES:

*

*   1) MPC860 Users Manual

*   2) PowerPC Microprocessor Family: The Programming Environments for

*      32-Bit Microprocessors

*

* HISTORY:

*

* 27 APR 98  jay    initial release

*

*-------------------------------------------------------------------------*/

#include <cyg/hal/quicc_smc2.h>

#include "ppc_860.h"

/***********************/

/* Global Declarations */

/***********************/

static EPPC  *IMMR;      /* IMMR base pointer */

static BDRINGS *RxTxBD;  /* buffer descriptors base pointer */

static LB *SMC2Buffers;  /* SMC2 base pointers */

/*---------------------*/

/* Function Prototypes */

/*---------------------*/

//static char  SMC2Poll(void);

static void  InitBDs(void);

//static void  EchoChar(void);

static unsigned long GetIMMR(void);

/*-----------------------------------------------------------------------------

*

* FUNCTION NAME:  cyg_smc2_init

*

* DESCRIPTION:

*

* EXTERNAL EFFECT:

*

* PARAMETERS:  None

*

* RETURNS: None

*

*---------------------------------------------------------------------------*/

void cyg_smc2_init(unsigned long baudRate)

{

   unsigned long *bcsr1;

   unsigned long clockRate = 20 * 1000 * 1000;  // 20Mhz

   unsigned long divider = clockRate / (baudRate * 16) - 1;

   /*------------------------*/

   /* Establish IMMR pointer */

   /*------------------------*/

   IMMR = (EPPC *)(GetIMMR() & 0xFFFF0000);  /* MPC8xx internal register

                                                map  */

   /*-----------------------------------------------*/

   /* Enable RS232 interface on ADS board via BCSR1 */

   /* Get the base address of BCSR                  */

   /*-----------------------------------------------*/

   bcsr1 = (unsigned long *) ((IMMR->memc_br1 & 0xffff0000) + 4);

   *bcsr1 &= ~(1 << 18);  // turn on RS232 port 2

   /*-----------------------*/

   /* Allow SMC2 TX, RX out */

   /*-----------------------*/

   IMMR->pip_pbpar |= (0x0C00);

   IMMR->pip_pbdir &= 0xF3FF;

   /*------------------------------------------------*/

   /* Set Baud Rate to 9600 for 40MHz System Clock.  */

   /* Enable BRG Count.                              */

   /*------------------------------------------------*/

   IMMR->brgc2 = ((divider << 1) | 0x10000);

   IMMR->si_simode &= ~(0xF0000000);    /* SCM2:  NMSI mode */

   IMMR->si_simode |= 0x10000000;       /* SCM2:  Tx/Rx Clocks are BRG2 */

   /*--------------------*/

   /* Initialize the BDs */

   /*--------------------*/

   InitBDs(); /* before setting up info depending on RxTxBD below */

   IMMR->smc_regs[SMC2_REG].smc_smce = 0xFF;  /* Clear any pending events */

   /*----------------------------------------*/

   /* Set RXBD table start at Dual Port +800 */

   /*----------------------------------------*/

   IMMR->PRAM[PAGE4].pg.other.smc_dsp2.psmc2.u2.rbase = (unsigned short) (unsigned) &RxTxBD->RxBD;

   /*----------------------------------------*/

   /* Set TXBD table start at Dual Port +808 */

   /*----------------------------------------*/

   IMMR->PRAM[PAGE4].pg.other.smc_dsp2.psmc2.u2.tbase = (unsigned short) (unsigned) &RxTxBD->TxBD;

   /*--------------------------------------*/

   /* Set RFCR,TFCR -- Rx,Tx Function Code */

   /* Normal Operation and Motorola byte   */

   /* ordering                             */

   /*--------------------------------------*/

   IMMR->PRAM[PAGE4].pg.other.smc_dsp2.psmc2.u2.rfcr = 0x18;

   IMMR->PRAM[PAGE4].pg.other.smc_dsp2.psmc2.u2.tfcr = 0x18;

   /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/

   /* Protocol Specific Parameters */

   /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/

   /*---------------------------*/

   /* MRBLR = MAX buffer length */

   /*---------------------------*/

   IMMR->PRAM[PAGE4].pg.other.smc_dsp2.psmc2.u2.mrblr = 1;

   /*------------------------------------*/

   /* MAX_IDL = Disable MAX Idle Feature */

   /*------------------------------------*/

   IMMR->PRAM[PAGE4].pg.other.smc_dsp2.psmc2.u2.max_idl = 0;

   /*-------------------------------------*/

   /* BRKEC = No break condition occurred */

   /*-------------------------------------*/

   IMMR->PRAM[PAGE4].pg.other.smc_dsp2.psmc2.u2.brkec = 0;

   /*---------------------------------------*/

   /* BRKCR = 1 break char sent on top XMIT */

   /*---------------------------------------*/

   IMMR->PRAM[PAGE4].pg.other.smc_dsp2.psmc2.u2.brkcr = 1;

   /* InitBDs() used to be here - no harm in doing this again */

   IMMR->smc_regs[SMC2_REG].smc_smce = 0xFF;  /* Clear any pending events */

   /*--------------------------------------------------*/

   /* SMC_SMCM = Mask all interrupts, use polling mode */

   /*--------------------------------------------------*/

   IMMR->smc_regs[SMC2_REG].smc_smcm = 0;

   IMMR->cpmi_cicr = 0;           /* Disable all CPM interrups */

   IMMR->cpmi_cipr = 0xFFFFFFFF;  /* Clear all pending interrupt events */

   IMMR->cpmi_cimr = 0;           /* Mask all event interrupts */

   /*------------------------------------*/

   /* 8-bit mode,  no parity, 1 stop-bit */

   /* UART SMC Mode                      */

   /* Normal operation (no loopback),    */

   /* SMC Transmitter/Receiver Enabled   */

   /*------------------------------------*/

   IMMR->smc_regs[SMC2_REG].smc_smcmr = 0x4823;

   /*---------------------------------------*/

   /* Initialize Rx and Tx Params for SMC2: */

   /* Spin until cpcr flag is cleared       */

   /*---------------------------------------*/

   for(IMMR->cp_cr = 0x00d1; IMMR->cp_cr & 0x0001;) ;

}

/*-----------------------------------------------------------------------------

*

* FUNCTION NAME:  InitBDs

*

* DESCRIPTION: This function initializes the Tx and Rx Buffer Descriptors.

*

* EXTERNAL EFFECT: RxTxBD

*

* PARAMETERS:  None

*

* RETURNS: None

*

*---------------------------------------------------------------------------*/

static void InitBDs(void)

{

   /*--------------------------------------------------------------------*/

   /* We add 64 bytes to the start of the buffer descriptors because     */

   /* this code was also tested on the monitor version of SDS debugger.  */

   /* The monitor program on our target uses most of the first 64 bytes  */

   /* for buffer descriptors. If you are not using the SDS monitor  with */

   /* Motorola's ADS development board, you can delete 64 below and      */

   /* start at the beginning of this particular block of Dual Port RAM.  */

   /*--------------------------------------------------------------------*/

   /*----------------------------------*/

   /* Get pointer to BD area on DP RAM */

   /*----------------------------------*/

   RxTxBD = (BDRINGS *)(IMMR->qcp_or_ud.ud.udata_bd + 64);

   /*-------------------------------------------------------------------*/

   /* Establish the buffer pool in Dual Port RAM. We do this because the*/

   /* pool size is only 2 bytes (1 for Rx and 1 for Tx) and to avoid    */

   /* disabling data cache for the memory region where BufferPool would */

   /* reside. The CPM does not recognize data in buffer pools once it   */

   /* been cached. It's acesses are direct through DMA to external      */

   /* memory.                                                           */

   /*-------------------------------------------------------------------*/

   SMC2Buffers = (LB *)(IMMR->qcp_or_ud.ud.udata_bd + 80);

   /*-----------------------------------*/

   /* Setup Receiver Buffer Descriptors */

   /*-----------------------------------*/

   RxTxBD->RxBD.bd_cstatus = 0xA000;            /* Enable, Last BD */

   RxTxBD->RxBD.bd_length = 1;

   RxTxBD->RxBD.bd_addr = &(SMC2Buffers->RxBuffer);

   /*--------------------------------------*/

   /* Setup Transmitter Buffer Descriptors */

   /*--------------------------------------*/

   RxTxBD->TxBD.bd_cstatus = 0x2000;      /* Buffer not yet ready; Last BD */

   RxTxBD->TxBD.bd_length = 1;

   RxTxBD->TxBD.bd_addr = &(SMC2Buffers->TxBuffer);

} /* END InitBDs */

#if 0 // static unused function. -jskov 19990122

/*-----------------------------------------------------------------------------

*

* FUNCTION NAME:  EchoChar

*

* DESCRIPTION: This function facilitates the echoing of a received character.

*

* EXTERNAL EFFECT: RxTxBD

*

* PARAMETERS:  None

*

* RETURNS: None

*

*---------------------------------------------------------------------------*/

static void  EchoChar(void)

{

   char mych;

   mych = cyg_smc2_getchar();

   cyg_smc2_putchar(mych);

} /* end EchoChar */

#endif

/*-----------------------------------------------------------------------------

*

* FUNCTION NAME:  cyg_smc2_putchar

*

* DESCRIPTION: Output a character to SMC2

*

* EXTERNAL EFFECT: RxTxBD

*

* PARAMETERS:  ch - input character

*

* RETURNS: None

*

*---------------------------------------------------------------------------*/

void cyg_smc2_putchar(char ch)

{

  /*-----------------------------------*/

  /* Loop until transmission completed */

  /*-----------------------------------*/

   while (RxTxBD->TxBD.bd_cstatus  &  0x8000);

   /*------------*/

   /* Store data */

   /*------------*/

   *(RxTxBD->TxBD.bd_addr) = ch;

   RxTxBD->TxBD.bd_length = 1;

   /*---------------*/

   /* Set Ready bit */

   /*---------------*/

   RxTxBD->TxBD.bd_cstatus |= 0x8000;

}

/*-----------------------------------------------------------------------------

*

* FUNCTION NAME:  cyg_smc2_getchar

*

* DESCRIPTION: Get a character from SMC2

*

* EXTERNAL EFFECT: RxTxBD

*

* PARAMETERS:  NONE

*

* RETURNS: A character from SMC2

*

*---------------------------------------------------------------------------*/

char cyg_smc2_getchar(void)

{

    char ch;   /* output character from SMC2 */

    /*--------------------*/

    /* Loop if RxBD empty */

    /*--------------------*/

    while (RxTxBD->RxBD.bd_cstatus  &  0x8000);

    /*--------------*/

    /* Receive data */

    /*--------------*/

    ch = *(RxTxBD->RxBD.bd_addr);

    /*----------------------*/

    /* Set Buffer Empty bit */

    /*----------------------*/

    RxTxBD->RxBD.bd_cstatus |= 0x8000;

    return ch;

}

#if 0 // static unused function. -jskov 19990122

/*-----------------------------------------------------------------------------

*

* FUNCTION NAME:  SMC2Poll

*

* DESCRIPTION: Poll SMC2 RxBD and check to see if a character was received

*

* EXTERNAL EFFECT: NONE

*

* PARAMETERS:  NONE

*

* RETURNS: A one if there is a character available in the receive buffer,

*          else zero.

*

*---------------------------------------------------------------------------*/

static char SMC2Poll(void)

{

  return (RxTxBD->RxBD.bd_cstatus & 0x8000) ? 0 : 1;

} /* END SMC2Poll */

#endif

/*-----------------------------------------------------------------------------

*

* FUNCTION NAME:  GetIMMR

*

* DESCRIPTION: Returns current value in the IMMR register.

*

* EXTERNAL EFFECT: NONE

*

* PARAMETERS:  NONE

*

* RETURNS: The IMMR value in r3. The compiler uses r3 as the register

*          containing the return value.

*

*---------------------------------------------------------------------------*/

static unsigned long GetIMMR(void)

{

    unsigned long ret;

    asm volatile (" mfspr  %0,638 " : "=r" (ret));  /* IMMR is spr #638 */

    return ret;

}

/* EOF hal/powerpc/fads/quicc_smc2.c */