aal2rxrxbyte.c

摩托罗拉Motolola公司网络处理器C3的示范代码.实现了ATM的AAL2层交换功能.想了解网络处理器的可以

    Branch(ALWAYS, Upc + 1);                       /* Upc = 32 */

    Bbus(IregsB(TEMP));
    ALU(PassB);
    Abus(IregsA(UUI_IREG));
    Actions(IregsAwrite);
    Branch(ALWAYS, Upc + 1);                       /* Upc = 33 */

    /* Rotate UUI_IREG by 5 so that UUI moves into right position.
     * UUI_IREG(1:5) to UUI_IREG(4:0) */
    Bbus(IregsB(UUI_IREG));
    ALU(RotateB(5));
    IregsA(UUI_IREG);
    Actions(IregsAwrite);
    Branch(ALWAYS, Upc + 1);                       /* Upc = 34 */

    /* Its possible that we get Data9 in between the header */
    Branch(Data9, Label(HANDLE_DATA9_IN_HEADER));       /* Upc = 30 */
    /* The Data9 byte has to be removed from the FIFO */


/* Test for pad bytes */
LabelDef(TEST_FOR_PAD);
    DCPSIM_MESSAGE(Test for pad bytes);
    Bbus(IregsB(CID_IREG));
    ALU(PassB);
    Branch(ALWAYS, Upc + 1);                       /* Upc = 35 */
    Branch(ALUzero, Label(SET_DUMP_ALL));          /* Upc = 36 */


/* Test for CRC5 of above header */
LabelDef(TEST_FOR_CRC5);
    DCPSIM_MESSAGE(Test for CRC5 pass);
    Abus(Literal(0x1F));
    Bbus(CRC5);
    ALU(AND);
    Branch(ALWAYS, Upc + 1);                       /* Upc = 39 */
    Branch(ALUzero, Label(WRITE_PAYLOAD_TO_RC));   /* Upc = 40 */

    /* If CRC5 failed set CRC5 error in the extract space */
    DCPSIM_MESSAGE(CRC5 Failed);
    CregsAddrWrite(EXTRACT_SPACE_OFFSET(crc5Indicator));
    Branch(ALWAYS, Upc+1);                         /* Upc = 50 */
    CregInit(0x01);
    Branch(ALWAYS, Upc+1);                         /* Upc = 51 */

/* Test for a partial packet or OSF byte. if OSF exists then reading of
   Corrupt cell can be resumed from OSF + 1. */
LabelDef(TEST_FOR_PARTIAL_PACKET);
    DCPSIM_MESSAGE(Test for partial packet);
    IregCompareLit(PARTIAL_PAYLOAD_LEN, 0x00);
    Branch(ALWAYS, Upc+1);                         /* Upc = 41 */
    BranchNot(ALUzero, Label(DISCARD_PAYLOAD));    /* Upc = 42 */

/* Set the PPL to a high value such that discard takes place till Data9.
   Set the new cell flag */
LabelDef(SET_DUMP_ALL);
    DCPSIM_MESSAGE(Dump rest of the data);
    IregInit(PARTIAL_PAYLOAD_LEN, 0x40, UseAbus);
    Branch(ALWAYS, Upc+1);                         /* Upc = 43 */

    IregInit(NEW_CELL, 0x01, UseAbus);
    Branch(ALWAYS, Upc+1);                         /* Upc = 44 */


/* Either drop PARTIAL_PAYLOAD_LEN bytes of data or
 * Stop dropping at Data9 arival.*/
LabelDef(DISCARD_PAYLOAD);
    DCPSIM_MESSAGE(Discard the payload);
    IregSUBlit(PARTIAL_PAYLOAD_LEN, 0x03);
    Branch(ALWAYS, Upc + 1);                       /* Upc = 45 */

    /* Convert PARTIAL_PAYLOAD_LEN to its negative */
    Abus(Literal(0xFF));
    Bbus(IregsB(PARTIAL_PAYLOAD_LEN));
    ALU(SUB);
    IregsA(COUNTER);
    Actions(IregsAwrite);
    Branch(ALWAYS, Upc + 1);                       /* Upc = 45 */

    //Actions(UnloadFIFO);
    //Branch(ALWAYS, Upc + 1);                       /* Upc = 45 */

    /* Keep unloading FIFO and incrementing PARTIAL_PAYLOAD_LEN till
     * PARTIAL_PAYLOAD_LEN becomes all ones or a Data9 byte is got */
LabelDef(DROP_DATA);
    Actions(IregIncr(COUNTER) + UnloadFIFO);
    Branch(ALWAYS, Upc + 1);                       /* Upc = 46 */
    Branch(Data9, Label(SET_ERROR_IN_EXTRACT_SPACE)); /* Upc = 47 */
    Branch(AllOnes(COUNTER), Label(SET_ERROR_IN_EXTRACT_SPACE)); /* Upc = 48 */
    Branch(ALWAYS, Label(DROP_DATA));              /* Upc = 49 */


/* Handle the CPS packet errors
 * Set CRC5 failure (-1) in the extract space.*/
LabelDef(SET_ERROR_IN_EXTRACT_SPACE);
    DCPSIM_MESSAGE(Set error in extract space);
    CregsAddrWrite(EXTRACT_SPACE_OFFSET(goodCpsPacket));
    Branch(ALWAYS, Upc+1);                         /* Upc = 50 */
    CregInit(0x00);
    Branch(ALWAYS, Upc+1);                         /* Upc = 51 */

    /* Write the address of extract space endOfCell
       to CREG and store New Cell Ireg in it. */
    CregsAddrWrite(EXTRACT_SPACE_OFFSET(endOfCell));
    IregToCregs(NEW_CELL);
    Branch(ALWAYS, Upc+1);                         /* Upc = 52 */

    /* FOR DEBUGGING:
     * Using these lines one can check if the a proper header was
     * received in case of a packet error.*/
    /* Write the address of extract space CID to CREG and store byte */
    // THIS BEING ADDED FOR FIXING CRC5 PROBLEM ON HARDWARE
    // CregsAddrWrite(EXTRACT_SPACE_OFFSET(cid));
    // IregToCregs(CID_IREG);
    // Branch(ALWAYS, Upc+1);                         /* Upc = 66 */

    /* Write the address of extract space LI to CREG
     * and store the data */
    // THIS BEING ADDED FOR FIXING CRC5 PROBLEM ON HARDWARE
    // CregsAddrWrite(EXTRACT_SPACE_OFFSET(li));
    // IregToCregs(LI_IREG);
    // Branch(ALWAYS, Upc+1);                         /* Upc = 67 */

    /* Write the UUI to the uui in extract space */
    // THIS BEING ADDED FOR FIXING CRC5 PROBLEM ON HARDWARE
    // CregsAddrWrite(EXTRACT_SPACE_OFFSET(uui));
    // IregToCregs(UUI_IREG);
    // Branch(ALWAYS, Upc+1);                         /* Upc = 68 */


/* Reset the availabilty of the extract space so that RC can start processing
 * the data. */
LabelDef(RELEASE_EXTRACT_SPACE);
    DCPSIM_MESSAGE(Release the extrace space);

    /* Set the extract avail flag, this should tell CPRC
     * when to read the extract space */
    CregsAddrWrite(EXTRACT_SPACE_OFFSET(extractAvailFlag));
    Branch(ALWAYS, Upc+1);                         /* Upc = 71 */
    CregInit(0x01);
    Branch(ALWAYS, Upc+1);                         /* Upc = 72 */

    /* Set the CPS header len and partial payload lenght to 0. */
    IregInit(CPS_HEADER_LEN, 0x00, UseAbus);
    Branch(ALWAYS, Upc+1);                         /* Upc = 53 */
    IregInit(PARTIAL_PAYLOAD_LEN, 0x00, UseAbus);
    Branch(ALWAYS, Upc+1);                         /* Upc = 54 */

    /* Handover the extract space to the CPRC */
    CregsAddrWrite(RXSTATUS);
    Branch(ALWAYS, Upc+1);                         /* Upc = 55 */
    CregInit(0x80);
    Branch(ALWAYS, Upc+1);                         /* Upc = 56 */
    Branch(AllOnes(COUNTER), Label(GO_TO_POLL_EXTRACT_SPACE));
    BranchNot(Data9, Label(GO_TO_POLL_EXTRACT_SPACE));

    /* Remove the last byte only after the extract space has been
     * released. Otherwise the unloadFIFO will block the processing. */
    Actions(UnloadFIFO);
    Branch(ALWAYS, Upc+1);                         /* upc = */

LabelDef(GO_TO_POLL_EXTRACT_SPACE);
    Branch(ALWAYS, Label(POLL_EXTRACT_SPACE));     /* Upc = 57 */


/* Write data to the Extract space or till PARTIAL_PAYLOAD_LEN bytes
 * of data has been written or you get a Data9 from the FIFO */
LabelDef(WRITE_PAYLOAD_TO_RC);
    Abus(Literal(0xFE));
    Bbus(IregsB(LI_IREG));
    ALU(SUB);
    IregsA(COUNTER);
    Actions(IregsAwrite + UnloadFIFO);
    Branch(ALWAYS, Upc + 1);                       /* Upc = 58 */

    /* Initialize PARTIAL_PAYLOAD_LEN to 0, so that we can count the no. of
     * bytes sent to the CPRC */
    IregInit(PARTIAL_PAYLOAD_LEN, 0x00, UseAbus);
    Branch(ALWAYS, Upc + 1);                       /* Upc = 59 */
    Branch(Data9, Label(SEND_LAST_BYTE_OUT));


/* Start unloading the data check for Data9 or counter */
LabelDef(GET_DATA);
    Abus(Payload);
    ALU(PassA);
    Pbus(ALUout);
    Actions(UnloadFIFO + DataOutValid + IregIncr(COUNTER) + IregIncr(PARTIAL_PAYLOAD_LEN));
    Branch(ALWAYS, Upc + 1);                       /* Upc = 59 */ 
    Branch(Data9, Label(SEND_LAST_BYTE_OUT));      /* Upc = 61 */
    Branch(AllOnes(COUNTER), Label(WRITE_TO_EXTRACT_SPACE)); /* Upc = 62 */
    Branch(ALWAYS, Label(GET_DATA));               /* Upc = 63 */


/* Remove the Data9 byte because of which control came here */
LabelDef(SEND_LAST_BYTE_OUT);
    Branch(AllOnes(COUNTER), Label(WRITE_TO_EXTRACT_SPACE)); /* Upc = 62 */
    Abus(Payload);
    ALU(PassA);
    Pbus(ALUout);
    Actions(DataOutValid + IregIncr(COUNTER) + IregIncr(PARTIAL_PAYLOAD_LEN));
    Branch(ALWAYS, Upc+1);      /* Upc =  */


/* In case the data transmission stopped due to Data9, then Set
   NEW_CELL byte to 1. */
LabelDef(SET_NEW_CELL_FLAG);
    DCPSIM_MESSAGE(Set the new cell flag);
    IregInit(NEW_CELL, 0x01, UseAbus);
    Branch(ALWAYS, Upc+1);                         /* Upc =  */


/* Write CPS header bytes CID_IREG, LI_IREG and UUI_IREG to the
 * Extract space */
LabelDef(WRITE_TO_EXTRACT_SPACE);
    DCPSIM_MESSAGE(Write data to the Extract space);

    /* Write the address of extract space CPS header length to CREG
     * and store the byte */
    CregsAddrWrite(EXTRACT_SPACE_OFFSET(cpsHdrLen));
    IregToCregs(CPS_HEADER_LEN);
    Branch(ALWAYS, Upc+1);                         /* Upc = 69 */

    /* Write the address of extract space CPS payload length to CREG
     * and store the data */
    CregsAddrWrite(EXTRACT_SPACE_OFFSET(cpsPayloadLen));
    IregToCregs(PARTIAL_PAYLOAD_LEN);
    Branch(ALWAYS, Upc+1);                         /* Upc = 70 */

    /* Write the address of extract space CID to CREG and store byte */
    CregsAddrWrite(EXTRACT_SPACE_OFFSET(cid));
    IregToCregs(CID_IREG);
    Branch(ALWAYS, Upc+1);                         /* Upc = 66 */

    /* Write the address of extract space LI to CREG
     * and store the data */
    CregsAddrWrite(EXTRACT_SPACE_OFFSET(li));
    IregToCregs(LI_IREG);
    Branch(ALWAYS, Upc+1);                         /* Upc = 67 */

    /* Write the UUI to the uui in extract space */
    CregsAddrWrite(EXTRACT_SPACE_OFFSET(uui));
    IregToCregs(UUI_IREG);
    Branch(ALWAYS, Upc+1);                         /* Upc = 68 */

    /* Write the address of extract space endOfCell result to CREG
     * and store the data */
    CregsAddrWrite(EXTRACT_SPACE_OFFSET(endOfCell));
    IregToCregs(NEW_CELL);
    Branch(ALWAYS, Upc+1);                         /* Upc = 73 */

    /* If CPS_HEADER_LEN == 3 and LI_IREG + 1 == PARTIAL_PAYLOAD_LEN then
     * Set cpsPckComplete to 0x01. */
    Abus(IregsA(CPS_HEADER_LEN));
    Bbus(Literal(0x03));
    ALU(SUB);
    Branch(ALWAYS, Upc+1);
    BranchNot(ALUzero, Label(RELEASE_EXTRACT_SPACE));

    Abus(Literal(0x01));
    Bbus(IregsB(LI_IREG));
    ALU(ADD);
    IregsA(TEMP);
    Actions(IregsAwrite);
    Branch(ALWAYS, Upc+1);

    Abus(IregsA(TEMP));
    Bbus(IregsB(PARTIAL_PAYLOAD_LEN));
    ALU(XOR);
    Branch(ALWAYS, Upc+1);
    BranchNot(ALUzero, Label(RELEASE_EXTRACT_SPACE));  /* Upc = 74 */

    /* This is an exact match for the CPS packet */
    CregsAddrWrite(EXTRACT_SPACE_OFFSET(cpsPckComplete));
    Branch(ALWAYS, Upc+1);                         /* Upc = 50 */
    CregInit(0x01);
    Branch(ALWAYS, Upc+1);                         /* Upc = 51 */

    /* Always go to RELEASE_EXTRACT_SPACE from here */
    Branch(ALWAYS, Label(RELEASE_EXTRACT_SPACE));  /* Upc = 74 */


/* Write data to the Extract space or till PARTIAL_PAYLOAD_LEN bytes
 * of data has been written or you get a Data9 from the FIFO */
LabelDef(WRITE_PART_PAYLOAD_TO_RC);
    Abus(Literal(0xFF));
    Bbus(IregsB(PARTIAL_PAYLOAD_LEN));
    ALU(SUB);
    IregsA(COUNTER);
    Actions(IregsAwrite + UnloadFIFO);
    Branch(ALWAYS, Upc + 1);                       /* Upc = 58 */

    /* Initialize PARTIAL_PAYLOAD_LEN to 0, so that we can count the no. of
     * bytes sent to the CPRC */
    IregInit(PARTIAL_PAYLOAD_LEN, 0x00, UseAbus);
    Branch(ALWAYS, Upc + 1);                       /* Upc = 58 */
    Branch(ALWAYS, Label(GET_DATA));                       /* Upc = 59 */

LabelDef(HANDLE_DATA9_IN_HEADER);
    /* Four things have to be taken care off
     * 1. CRC5 check needs to be done.
     * 2. padding check needs to be done.
     * 3. Set new cell indication.
     * 4. Data9 has to be removed from the FIFO
     *    on releasing extract space.*/
    IregInit(NEW_CELL, 0x01, UseAbus);
    Branch(ALWAYS, Upc+1);                         /* Upc =  */

    Bbus(IregsB(CID_IREG));
    ALU(PassB);
    Branch(ALWAYS, Upc + 1);                       /* Upc = 35 */
    Branch(ALUzero, Label(SET_ERROR_IN_EXTRACT_SPACE));          /* Upc = 36 */

    /* Only if the header length is 3 do the CRC5 check */
    Abus(Literal(0x03));
    Bbus(IregsB(CPS_HEADER_LEN));
    ALU(SUB);
    Branch(ALWAYS, Upc + 1);
    BranchNot(ALUzero, Label(WRITE_TO_EXTRACT_SPACE));

    DCPSIM_MESSAGE(Test for CRC5 on patial packet);
    Abus(Literal(0x1F));
    Bbus(CRC5);
    ALU(AND);
    Branch(ALWAYS, Upc + 1);
    Branch(ALUzero, Label(WRITE_TO_EXTRACT_SPACE));          /* Upc = 36 */

    /* If CRC5 failed set CRC5 error in the extract space
     * also set the bad CPS packet indication */
    DCPSIM_MESSAGE(CRC5 Failed);
    CregsAddrWrite(EXTRACT_SPACE_OFFSET(crc5Indicator));
    Branch(ALWAYS, Upc+1);                         /* Upc = 50 */
    CregInit(0x01);
    Branch(ALWAYS, Upc+1);                         /* Upc = 51 */
    Branch(ALWAYS, Label(SET_ERROR_IN_EXTRACT_SPACE));          /* Upc = 36 */

}