freebsd-dev/sys/i4b/layer1/isic/i4b_isac.c

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/*
* Copyright (c) 1997, 2001 Hellmuth Michaelis. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*---------------------------------------------------------------------------
*
* i4b_isac.c - i4b siemens isdn chipset driver ISAC handler
* ---------------------------------------------------------
*
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* $FreeBSD$
*
* last edit-date: [Wed Jan 24 09:10:36 2001]
*
*---------------------------------------------------------------------------*/
#include "opt_i4b.h"
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#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
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#include <sys/socket.h>
#include <net/if.h>
#include <machine/i4b_debug.h>
#include <machine/i4b_ioctl.h>
#include <machine/i4b_trace.h>
#include <i4b/layer1/i4b_l1.h>
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#include <i4b/layer1/isic/i4b_isic.h>
#include <i4b/layer1/isic/i4b_isac.h>
#include <i4b/layer1/isic/i4b_hscx.h>
#include <i4b/include/i4b_global.h>
#include <i4b/include/i4b_mbuf.h>
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static u_char isic_isac_exir_hdlr(register struct l1_softc *sc, u_char exir);
static void isic_isac_ind_hdlr(register struct l1_softc *sc, int ind);
/*---------------------------------------------------------------------------*
* ISAC interrupt service routine
*---------------------------------------------------------------------------*/
void
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isic_isac_irq(struct l1_softc *sc, int ista)
{
register u_char c = 0;
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NDBGL1(L1_F_MSG, "unit %d: ista = 0x%02x", sc->sc_unit, ista);
if(ista & ISAC_ISTA_EXI) /* extended interrupt */
{
c |= isic_isac_exir_hdlr(sc, ISAC_READ(I_EXIR));
}
if(ista & ISAC_ISTA_RME) /* receive message end */
{
register int rest;
u_char rsta;
/* get rx status register */
rsta = ISAC_READ(I_RSTA);
if((rsta & ISAC_RSTA_MASK) != 0x20)
{
int error = 0;
if(!(rsta & ISAC_RSTA_CRC)) /* CRC error */
{
error++;
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NDBGL1(L1_I_ERR, "unit %d: CRC error", sc->sc_unit);
}
if(rsta & ISAC_RSTA_RDO) /* ReceiveDataOverflow */
{
error++;
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NDBGL1(L1_I_ERR, "unit %d: Data Overrun error", sc->sc_unit);
}
if(rsta & ISAC_RSTA_RAB) /* ReceiveABorted */
{
error++;
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NDBGL1(L1_I_ERR, "unit %d: Receive Aborted error", sc->sc_unit);
}
if(error == 0)
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NDBGL1(L1_I_ERR, "unit %d: RME unknown error, RSTA = 0x%02x!", sc->sc_unit, rsta);
i4b_Dfreembuf(sc->sc_ibuf);
c |= ISAC_CMDR_RMC|ISAC_CMDR_RRES;
sc->sc_ibuf = NULL;
sc->sc_ib = NULL;
sc->sc_ilen = 0;
ISAC_WRITE(I_CMDR, ISAC_CMDR_RMC|ISAC_CMDR_RRES);
ISACCMDRWRDELAY();
return;
}
rest = (ISAC_READ(I_RBCL) & (ISAC_FIFO_LEN-1));
if(rest == 0)
rest = ISAC_FIFO_LEN;
if(sc->sc_ibuf == NULL)
{
if((sc->sc_ibuf = i4b_Dgetmbuf(rest)) != NULL)
sc->sc_ib = sc->sc_ibuf->m_data;
else
panic("isic_isac_irq: RME, i4b_Dgetmbuf returns NULL!\n");
sc->sc_ilen = 0;
}
if(sc->sc_ilen <= (MAX_DFRAME_LEN - rest))
{
ISAC_RDFIFO(sc->sc_ib, rest);
sc->sc_ilen += rest;
sc->sc_ibuf->m_pkthdr.len =
sc->sc_ibuf->m_len = sc->sc_ilen;
if(sc->sc_trace & TRACE_D_RX)
{
i4b_trace_hdr_t hdr;
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hdr.unit = L0ISICUNIT(sc->sc_unit);
hdr.type = TRC_CH_D;
hdr.dir = FROM_NT;
hdr.count = ++sc->sc_trace_dcount;
MICROTIME(hdr.time);
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i4b_l1_trace_ind(&hdr, sc->sc_ibuf->m_len, sc->sc_ibuf->m_data);
}
c |= ISAC_CMDR_RMC;
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if(sc->sc_enabled &&
(ctrl_desc[sc->sc_unit].protocol != PROTOCOL_D64S))
{
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i4b_l1_ph_data_ind(L0ISICUNIT(sc->sc_unit), sc->sc_ibuf);
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}
else
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{
i4b_Dfreembuf(sc->sc_ibuf);
}
}
else
{
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NDBGL1(L1_I_ERR, "RME, input buffer overflow!");
i4b_Dfreembuf(sc->sc_ibuf);
c |= ISAC_CMDR_RMC|ISAC_CMDR_RRES;
}
sc->sc_ibuf = NULL;
sc->sc_ib = NULL;
sc->sc_ilen = 0;
}
if(ista & ISAC_ISTA_RPF) /* receive fifo full */
{
if(sc->sc_ibuf == NULL)
{
if((sc->sc_ibuf = i4b_Dgetmbuf(MAX_DFRAME_LEN)) != NULL)
sc->sc_ib= sc->sc_ibuf->m_data;
else
panic("isic_isac_irq: RPF, i4b_Dgetmbuf returns NULL!\n");
sc->sc_ilen = 0;
}
if(sc->sc_ilen <= (MAX_DFRAME_LEN - ISAC_FIFO_LEN))
{
ISAC_RDFIFO(sc->sc_ib, ISAC_FIFO_LEN);
sc->sc_ilen += ISAC_FIFO_LEN;
sc->sc_ib += ISAC_FIFO_LEN;
c |= ISAC_CMDR_RMC;
}
else
{
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NDBGL1(L1_I_ERR, "RPF, input buffer overflow!");
i4b_Dfreembuf(sc->sc_ibuf);
sc->sc_ibuf = NULL;
sc->sc_ib = NULL;
sc->sc_ilen = 0;
c |= ISAC_CMDR_RMC|ISAC_CMDR_RRES;
}
}
if(ista & ISAC_ISTA_XPR) /* transmit fifo empty (XPR bit set) */
{
if((sc->sc_obuf2 != NULL) && (sc->sc_obuf == NULL))
{
sc->sc_freeflag = sc->sc_freeflag2;
sc->sc_obuf = sc->sc_obuf2;
sc->sc_op = sc->sc_obuf->m_data;
sc->sc_ol = sc->sc_obuf->m_len;
sc->sc_obuf2 = NULL;
#ifdef NOTDEF
printf("ob2=%x, op=%x, ol=%d, f=%d #",
sc->sc_obuf,
sc->sc_op,
sc->sc_ol,
sc->sc_state);
#endif
}
else
{
#ifdef NOTDEF
printf("ob=%x, op=%x, ol=%d, f=%d #",
sc->sc_obuf,
sc->sc_op,
sc->sc_ol,
sc->sc_state);
#endif
}
if(sc->sc_obuf)
{
ISAC_WRFIFO(sc->sc_op, min(sc->sc_ol, ISAC_FIFO_LEN));
if(sc->sc_ol > ISAC_FIFO_LEN) /* length > 32 ? */
{
sc->sc_op += ISAC_FIFO_LEN; /* bufferptr+32 */
sc->sc_ol -= ISAC_FIFO_LEN; /* length - 32 */
c |= ISAC_CMDR_XTF; /* set XTF bit */
}
else
{
if(sc->sc_freeflag)
{
i4b_Dfreembuf(sc->sc_obuf);
sc->sc_freeflag = 0;
}
sc->sc_obuf = NULL;
sc->sc_op = NULL;
sc->sc_ol = 0;
c |= ISAC_CMDR_XTF | ISAC_CMDR_XME;
}
}
else
{
sc->sc_state &= ~ISAC_TX_ACTIVE;
}
}
if(ista & ISAC_ISTA_CISQ) /* channel status change CISQ */
{
register u_char ci;
/* get command/indication rx register*/
ci = ISAC_READ(I_CIRR);
/* if S/Q IRQ, read SQC reg to clr SQC IRQ */
if(ci & ISAC_CIRR_SQC)
(void) ISAC_READ(I_SQRR);
/* C/I code change IRQ (flag already cleared by CIRR read) */
if(ci & ISAC_CIRR_CIC0)
isic_isac_ind_hdlr(sc, (ci >> 2) & 0xf);
}
if(c)
{
ISAC_WRITE(I_CMDR, c);
ISACCMDRWRDELAY();
}
}
/*---------------------------------------------------------------------------*
* ISAC L1 Extended IRQ handler
*---------------------------------------------------------------------------*/
static u_char
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isic_isac_exir_hdlr(register struct l1_softc *sc, u_char exir)
{
u_char c = 0;
if(exir & ISAC_EXIR_XMR)
{
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NDBGL1(L1_I_ERR, "EXIRQ Tx Message Repeat");
c |= ISAC_CMDR_XRES;
}
if(exir & ISAC_EXIR_XDU)
{
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NDBGL1(L1_I_ERR, "EXIRQ Tx Data Underrun");
c |= ISAC_CMDR_XRES;
}
if(exir & ISAC_EXIR_PCE)
{
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NDBGL1(L1_I_ERR, "EXIRQ Protocol Error");
}
if(exir & ISAC_EXIR_RFO)
{
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NDBGL1(L1_I_ERR, "EXIRQ Rx Frame Overflow");
c |= ISAC_CMDR_RMC|ISAC_CMDR_RRES;
}
if(exir & ISAC_EXIR_SOV)
{
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NDBGL1(L1_I_ERR, "EXIRQ Sync Xfer Overflow");
}
if(exir & ISAC_EXIR_MOS)
{
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NDBGL1(L1_I_ERR, "EXIRQ Monitor Status");
}
if(exir & ISAC_EXIR_SAW)
{
/* cannot happen, STCR:TSF is set to 0 */
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NDBGL1(L1_I_ERR, "EXIRQ Subscriber Awake");
}
if(exir & ISAC_EXIR_WOV)
{
/* cannot happen, STCR:TSF is set to 0 */
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NDBGL1(L1_I_ERR, "EXIRQ Watchdog Timer Overflow");
}
return(c);
}
/*---------------------------------------------------------------------------*
* ISAC L1 Indication handler
*---------------------------------------------------------------------------*/
static void
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isic_isac_ind_hdlr(register struct l1_softc *sc, int ind)
{
register int event;
switch(ind)
{
case ISAC_CIRR_IAI8:
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NDBGL1(L1_I_CICO, "rx AI8 in state %s", isic_printstate(sc));
if(sc->sc_bustyp == BUS_TYPE_IOM2)
isic_isac_l1_cmd(sc, CMD_AR8);
event = EV_INFO48;
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i4b_l1_mph_status_ind(L0ISICUNIT(sc->sc_unit), STI_L1STAT, LAYER_ACTIVE, NULL);
break;
case ISAC_CIRR_IAI10:
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NDBGL1(L1_I_CICO, "rx AI10 in state %s", isic_printstate(sc));
if(sc->sc_bustyp == BUS_TYPE_IOM2)
isic_isac_l1_cmd(sc, CMD_AR10);
event = EV_INFO410;
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i4b_l1_mph_status_ind(L0ISICUNIT(sc->sc_unit), STI_L1STAT, LAYER_ACTIVE, NULL);
break;
case ISAC_CIRR_IRSY:
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NDBGL1(L1_I_CICO, "rx RSY in state %s", isic_printstate(sc));
event = EV_RSY;
break;
case ISAC_CIRR_IPU:
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NDBGL1(L1_I_CICO, "rx PU in state %s", isic_printstate(sc));
event = EV_PU;
break;
case ISAC_CIRR_IDR:
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NDBGL1(L1_I_CICO, "rx DR in state %s", isic_printstate(sc));
isic_isac_l1_cmd(sc, CMD_DIU);
event = EV_DR;
break;
case ISAC_CIRR_IDID:
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NDBGL1(L1_I_CICO, "rx DID in state %s", isic_printstate(sc));
event = EV_INFO0;
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i4b_l1_mph_status_ind(L0ISICUNIT(sc->sc_unit), STI_L1STAT, LAYER_IDLE, NULL);
break;
case ISAC_CIRR_IDIS:
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NDBGL1(L1_I_CICO, "rx DIS in state %s", isic_printstate(sc));
event = EV_DIS;
break;
case ISAC_CIRR_IEI:
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NDBGL1(L1_I_CICO, "rx EI in state %s", isic_printstate(sc));
isic_isac_l1_cmd(sc, CMD_DIU);
event = EV_EI;
break;
case ISAC_CIRR_IARD:
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NDBGL1(L1_I_CICO, "rx ARD in state %s", isic_printstate(sc));
event = EV_INFO2;
break;
case ISAC_CIRR_ITI:
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NDBGL1(L1_I_CICO, "rx TI in state %s", isic_printstate(sc));
event = EV_INFO0;
break;
case ISAC_CIRR_IATI:
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NDBGL1(L1_I_CICO, "rx ATI in state %s", isic_printstate(sc));
event = EV_INFO0;
break;
case ISAC_CIRR_ISD:
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NDBGL1(L1_I_CICO, "rx SD in state %s", isic_printstate(sc));
event = EV_INFO0;
break;
default:
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NDBGL1(L1_I_ERR, "UNKNOWN Indication 0x%x in state %s", ind, isic_printstate(sc));
event = EV_INFO0;
break;
}
isic_next_state(sc, event);
}
/*---------------------------------------------------------------------------*
* execute a layer 1 command
*---------------------------------------------------------------------------*/
void
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isic_isac_l1_cmd(struct l1_softc *sc, int command)
{
u_char cmd;
#ifdef I4B_SMP_WORKAROUND
/* XXXXXXXXXXXXXXXXXXX */
/*
* patch from Wolfgang Helbig:
*
* Here is a patch that makes i4b work on an SMP:
* The card (TELES 16.3) didn't interrupt on an SMP machine.
* This is a gross workaround, but anyway it works *and* provides
* some information as how to finally fix this problem.
*/
HSCX_WRITE(0, H_MASK, 0xff);
HSCX_WRITE(1, H_MASK, 0xff);
ISAC_WRITE(I_MASK, 0xff);
DELAY(100);
HSCX_WRITE(0, H_MASK, HSCX_A_IMASK);
HSCX_WRITE(1, H_MASK, HSCX_B_IMASK);
ISAC_WRITE(I_MASK, ISAC_IMASK);
/* XXXXXXXXXXXXXXXXXXX */
#endif /* I4B_SMP_WORKAROUND */
if(command < 0 || command > CMD_ILL)
{
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NDBGL1(L1_I_ERR, "illegal cmd 0x%x in state %s", command, isic_printstate(sc));
return;
}
if(sc->sc_bustyp == BUS_TYPE_IOM2)
cmd = ISAC_CIX0_LOW;
else
cmd = 0;
switch(command)
{
case CMD_TIM:
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NDBGL1(L1_I_CICO, "tx TIM in state %s", isic_printstate(sc));
cmd |= (ISAC_CIXR_CTIM << 2);
break;
case CMD_RS:
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NDBGL1(L1_I_CICO, "tx RS in state %s", isic_printstate(sc));
cmd |= (ISAC_CIXR_CRS << 2);
break;
case CMD_AR8:
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NDBGL1(L1_I_CICO, "tx AR8 in state %s", isic_printstate(sc));
cmd |= (ISAC_CIXR_CAR8 << 2);
break;
case CMD_AR10:
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NDBGL1(L1_I_CICO, "tx AR10 in state %s", isic_printstate(sc));
cmd |= (ISAC_CIXR_CAR10 << 2);
break;
case CMD_DIU:
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NDBGL1(L1_I_CICO, "tx DIU in state %s", isic_printstate(sc));
cmd |= (ISAC_CIXR_CDIU << 2);
break;
}
ISAC_WRITE(I_CIXR, cmd);
}
/*---------------------------------------------------------------------------*
* L1 ISAC initialization
*---------------------------------------------------------------------------*/
int
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isic_isac_init(struct l1_softc *sc)
{
ISAC_IMASK = 0xff; /* disable all irqs */
ISAC_WRITE(I_MASK, ISAC_IMASK);
if(sc->sc_bustyp != BUS_TYPE_IOM2)
{
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NDBGL1(L1_I_SETUP, "configuring for IOM-1 mode");
/* ADF2: Select mode IOM-1 */
ISAC_WRITE(I_ADF2, 0x00);
/* SPCR: serial port control register:
* SPU - software power up = 0
* SAC - SIP port high Z
* SPM - timing mode 0
* TLP - test loop = 0
* C1C, C2C - B1 and B2 switched to/from SPa
*/
ISAC_WRITE(I_SPCR, ISAC_SPCR_C1C1|ISAC_SPCR_C2C1);
/* SQXR: S/Q channel xmit register:
* SQIE - S/Q IRQ enable = 0
* SQX1-4 - Fa bits = 1
*/
ISAC_WRITE(I_SQXR, ISAC_SQXR_SQX1|ISAC_SQXR_SQX2|ISAC_SQXR_SQX3|ISAC_SQXR_SQX4);
/* ADF1: additional feature reg 1:
* WTC - watchdog = 0
* TEM - test mode = 0
* PFS - pre-filter = 0
* CFS - IOM clock/frame always active
* FSC1/2 - polarity of 8kHz strobe
* ITF - interframe fill = idle
*/
ISAC_WRITE(I_ADF1, ISAC_ADF1_FC2); /* ADF1 */
/* STCR: sync transfer control reg:
* TSF - terminal secific functions = 0
* TBA - TIC bus address = 7
* STx/SCx = 0
*/
ISAC_WRITE(I_STCR, ISAC_STCR_TBA2|ISAC_STCR_TBA1|ISAC_STCR_TBA0);
/* MODE: Mode Register:
* MDSx - transparent mode 2
* TMD - timer mode = external
* RAC - Receiver enabled
* DIMx - digital i/f mode
*/
ISAC_WRITE(I_MODE, ISAC_MODE_MDS2|ISAC_MODE_MDS1|ISAC_MODE_RAC|ISAC_MODE_DIM0);
}
else
{
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NDBGL1(L1_I_SETUP, "configuring for IOM-2 mode");
/* ADF2: Select mode IOM-2 */
ISAC_WRITE(I_ADF2, ISAC_ADF2_IMS);
/* SPCR: serial port control register:
* SPU - software power up = 0
* SPM - timing mode 0
* TLP - test loop = 0
* C1C, C2C - B1 + C1 and B2 + IC2 monitoring
*/
ISAC_WRITE(I_SPCR, 0x00);
/* SQXR: S/Q channel xmit register:
* IDC - IOM direction = 0 (master)
* CFS - Config Select = 0 (clock always active)
* CI1E - C/I channel 1 IRQ enable = 0
* SQIE - S/Q IRQ enable = 0
* SQX1-4 - Fa bits = 1
*/
ISAC_WRITE(I_SQXR, ISAC_SQXR_SQX1|ISAC_SQXR_SQX2|ISAC_SQXR_SQX3|ISAC_SQXR_SQX4);
/* ADF1: additional feature reg 1:
* WTC - watchdog = 0
* TEM - test mode = 0
* PFS - pre-filter = 0
* IOF - IOM i/f off = 0
* ITF - interframe fill = idle
*/
ISAC_WRITE(I_ADF1, 0x00);
/* STCR: sync transfer control reg:
* TSF - terminal secific functions = 0
* TBA - TIC bus address = 7
* STx/SCx = 0
*/
ISAC_WRITE(I_STCR, ISAC_STCR_TBA2|ISAC_STCR_TBA1|ISAC_STCR_TBA0);
/* MODE: Mode Register:
* MDSx - transparent mode 2
* TMD - timer mode = external
* RAC - Receiver enabled
* DIMx - digital i/f mode
*/
ISAC_WRITE(I_MODE, ISAC_MODE_MDS2|ISAC_MODE_MDS1|ISAC_MODE_RAC|ISAC_MODE_DIM0);
}
#ifdef NOTDEF
/*
* XXX a transmitter reset causes an ISAC tx IRQ which will not
* be serviced at attach time under some circumstances leaving
* the associated IRQ line on the ISA bus active. This prevents
* any further interrupts to be serviced because no low -> high
* transition can take place anymore. (-hm)
*/
/* command register:
* RRES - HDLC receiver reset
* XRES - transmitter reset
*/
ISAC_WRITE(I_CMDR, ISAC_CMDR_RRES|ISAC_CMDR_XRES);
ISACCMDRWRDELAY();
#endif
/* enabled interrupts:
* ===================
* RME - receive message end
* RPF - receive pool full
* XPR - transmit pool ready
* CISQ - CI or S/Q channel change
* EXI - extended interrupt
*/
ISAC_IMASK = ISAC_MASK_RSC | /* auto mode only */
ISAC_MASK_TIN | /* timer irq */
ISAC_MASK_SIN; /* sync xfer irq */
ISAC_WRITE(I_MASK, ISAC_IMASK);
return(0);
}