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path: root/drivers/char/rio/rioroute.c
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/*
** -----------------------------------------------------------------------------
**
**  Perle Specialix driver for Linux
**  Ported from existing RIO Driver for SCO sources.
 *
 *  (C) 1990 - 2000 Specialix International Ltd., Byfleet, Surrey, UK.
 *
 *      This program 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 of the License, or
 *      (at your option) any later version.
 *
 *      This program 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 this program; if not, write to the Free Software
 *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
**
**	Module		: rioroute.c
**	SID		: 1.3
**	Last Modified	: 11/6/98 10:33:46
**	Retrieved	: 11/6/98 10:33:50
**
**  ident @(#)rioroute.c	1.3
**
** -----------------------------------------------------------------------------
*/
#ifdef SCCS_LABELS
static char *_rioroute_c_sccs_ = "@(#)rioroute.c	1.3";
#endif

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/string.h>
#include <asm/semaphore.h>
#include <asm/uaccess.h>

#include <linux/termios.h>
#include <linux/serial.h>

#include <linux/generic_serial.h>


#include "linux_compat.h"
#include "rio_linux.h"
#include "typdef.h"
#include "pkt.h"
#include "daemon.h"
#include "rio.h"
#include "riospace.h"
#include "top.h"
#include "cmdpkt.h"
#include "map.h"
#include "riotypes.h"
#include "rup.h"
#include "port.h"
#include "riodrvr.h"
#include "rioinfo.h"
#include "func.h"
#include "errors.h"
#include "pci.h"

#include "parmmap.h"
#include "unixrup.h"
#include "board.h"
#include "host.h"
#include "error.h"
#include "phb.h"
#include "link.h"
#include "cmdblk.h"
#include "route.h"
#include "control.h"
#include "cirrus.h"
#include "rioioctl.h"
#include "param.h"
#include "list.h"
#include "sam.h"

static int RIOCheckIsolated(struct rio_info *, struct Host *, uint);
static int RIOIsolate(struct rio_info *, struct Host *, uint);
static int RIOCheck(struct Host *, uint);
static void RIOConCon(struct rio_info *, struct Host *, uint, uint, uint, uint, int);


/*
** Incoming on the ROUTE_RUP
** I wrote this while I was tired. Forgive me.
*/
int RIORouteRup( struct rio_info *p, uint Rup, struct Host *HostP, PKT *PacketP )
{
  struct PktCmd *PktCmdP = (struct PktCmd *)PacketP->data;
  struct PktCmd_M *PktReplyP;
  struct CmdBlk *CmdBlkP;
  struct Port *PortP;
  struct Map *MapP;
  struct Top *TopP;
  int ThisLink, ThisLinkMin, ThisLinkMax;
  int port;
  int Mod, Mod1, Mod2;
  ushort RtaType;
  uint RtaUniq;
  uint ThisUnit, ThisUnit2;	/* 2 ids to accommodate 16 port RTA */
  uint OldUnit, NewUnit, OldLink, NewLink;
  char *MyType, *MyName;
  int Lies;
  unsigned long flags;

#ifdef STACK
    RIOStackCheck("RIORouteRup");
#endif
#ifdef CHECK
    CheckPacketP(PacketP);
    CheckHostP(HostP);
    CheckRup(Rup);
    CheckHost(Host);
#endif
  /*
  ** Is this unit telling us it's current link topology?
  */
  if ( RBYTE(PktCmdP->Command) == ROUTE_TOPOLOGY )
  {
    MapP = HostP->Mapping;

    /*
    ** The packet can be sent either by the host or by an RTA.
    ** If it comes from the host, then we need to fill in the
    ** Topology array in the host structure. If it came in
    ** from an RTA then we need to fill in the Mapping structure's
    ** Topology array for the unit.
    */
    if ( Rup >= (ushort)MAX_RUP )
    {
      ThisUnit = HOST_ID;
      TopP = HostP->Topology;
      MyType = "Host";
      MyName = HostP->Name;
      ThisLinkMin = ThisLinkMax = Rup - MAX_RUP;
    }
    else
    {
      ThisUnit = Rup+1;
      TopP = HostP->Mapping[Rup].Topology;
      MyType = "RTA";
      MyName = HostP->Mapping[Rup].Name;
      ThisLinkMin = 0;
      ThisLinkMax = LINKS_PER_UNIT - 1;
    }

    /*
    ** Lies will not be tolerated.
    ** If any pair of links claim to be connected to the same
    ** place, then ignore this packet completely.
    */
    Lies = 0;
    for ( ThisLink=ThisLinkMin + 1; ThisLink <= ThisLinkMax; ThisLink++)
    {
      /*
      ** it won't lie about network interconnect, total disconnects
      ** and no-IDs. (or at least, it doesn't *matter* if it does)
      */
      if ( RBYTE(PktCmdP->RouteTopology[ThisLink].Unit) > (ushort)MAX_RUP )
	  continue;

      for ( NewLink=ThisLinkMin; NewLink < ThisLink; NewLink++ )
      {
        if ( (RBYTE(PktCmdP->RouteTopology[ThisLink].Unit) ==
              RBYTE(PktCmdP->RouteTopology[NewLink].Unit)) &&
	     (RBYTE(PktCmdP->RouteTopology[ThisLink].Link) ==
              RBYTE(PktCmdP->RouteTopology[NewLink].Link)) )
	{
          Lies++;
	}
      }
    }

    if ( Lies )
    {
      rio_dprintk (RIO_DEBUG_ROUTE, "LIES! DAMN LIES! %d LIES!\n",Lies);
      rio_dprintk (RIO_DEBUG_ROUTE, "%d:%c %d:%c %d:%c %d:%c\n",
          RBYTE(PktCmdP->RouteTopology[0].Unit), 
	  'A'+RBYTE(PktCmdP->RouteTopology[0].Link),
          RBYTE(PktCmdP->RouteTopology[1].Unit),
	  'A'+RBYTE(PktCmdP->RouteTopology[1].Link),
          RBYTE(PktCmdP->RouteTopology[2].Unit),
	  'A'+RBYTE(PktCmdP->RouteTopology[2].Link),
          RBYTE(PktCmdP->RouteTopology[3].Unit),
	  'A'+RBYTE(PktCmdP->RouteTopology[3].Link));
      return TRUE;
    }

    /*
    ** now, process each link.
    */
    for ( ThisLink=ThisLinkMin; ThisLink <= ThisLinkMax; ThisLink++)
    {
      /*
      ** this is what it was connected to
      */
      OldUnit = TopP[ThisLink].Unit;
      OldLink = TopP[ThisLink].Link;

      /*
      ** this is what it is now connected to
      */
      NewUnit = RBYTE(PktCmdP->RouteTopology[ThisLink].Unit);
      NewLink = RBYTE(PktCmdP->RouteTopology[ThisLink].Link);

      if ( OldUnit != NewUnit || OldLink != NewLink )
      {
	/*
	** something has changed!
	*/

        if ( NewUnit > MAX_RUP &&
	     NewUnit != ROUTE_DISCONNECT &&
	     NewUnit != ROUTE_NO_ID &&
	     NewUnit != ROUTE_INTERCONNECT )
	{
	    rio_dprintk (RIO_DEBUG_ROUTE, "I have a link from %s %s to unit %d:%d - I don't like it.\n",
		  MyType,
		  MyName,
		  NewUnit,
		  NewLink);
	}
	else
	{
	  /*
	  ** put the new values in
	  */
	  TopP[ThisLink].Unit = NewUnit;
	  TopP[ThisLink].Link = NewLink;

	  RIOSetChange(p);

	  if ( OldUnit <= MAX_RUP )
	  {
	    /*
	    ** If something has become bust, then re-enable them messages
	    */
	    if (! p->RIONoMessage)
		RIOConCon(p,HostP,ThisUnit,ThisLink,OldUnit,OldLink,DISCONNECT);
	  }

	  if ( ( NewUnit <= MAX_RUP ) && !p->RIONoMessage )
	    RIOConCon(p,HostP,ThisUnit,ThisLink,NewUnit,NewLink,CONNECT);

	  if ( NewUnit == ROUTE_NO_ID )
	    rio_dprintk (RIO_DEBUG_ROUTE, "%s %s (%c) is connected to an unconfigured unit.\n",
		    MyType,MyName,'A'+ThisLink);

	  if ( NewUnit == ROUTE_INTERCONNECT )
	  {
	    if (! p->RIONoMessage)
		cprintf("%s '%s' (%c) is connected to another network.\n", MyType,MyName,'A'+ThisLink);
	  }

	  /*
	  ** perform an update for 'the other end', so that these messages
	  ** only appears once. Only disconnect the other end if it is pointing
	  ** at us!
	  */
	  if ( OldUnit == HOST_ID )
	  {
	    if ( HostP->Topology[OldLink].Unit == ThisUnit &&
		 HostP->Topology[OldLink].Link == ThisLink )
	    {
	      rio_dprintk (RIO_DEBUG_ROUTE, "SETTING HOST (%c) TO DISCONNECTED!\n", OldLink+'A');
	      HostP->Topology[OldLink].Unit = ROUTE_DISCONNECT;
	      HostP->Topology[OldLink].Link = NO_LINK;
	    }
	    else
	    {
	      rio_dprintk (RIO_DEBUG_ROUTE, "HOST(%c) WAS NOT CONNECTED TO %s (%c)!\n",
		    OldLink+'A',HostP->Mapping[ThisUnit-1].Name,ThisLink+'A');
	    }
	  }
	  else if ( OldUnit <= MAX_RUP )
	  {
	    if ( HostP->Mapping[OldUnit-1].Topology[OldLink].Unit == ThisUnit &&
	         HostP->Mapping[OldUnit-1].Topology[OldLink].Link == ThisLink )
	    {
	      rio_dprintk (RIO_DEBUG_ROUTE, "SETTING RTA %s (%c) TO DISCONNECTED!\n",
				   HostP->Mapping[OldUnit-1].Name,OldLink+'A');
	      HostP->Mapping[OldUnit-1].Topology[OldLink].Unit=ROUTE_DISCONNECT;
	      HostP->Mapping[OldUnit-1].Topology[OldLink].Link=NO_LINK;
	    }
	    else
	    {
	      rio_dprintk (RIO_DEBUG_ROUTE, "RTA %s (%c) WAS NOT CONNECTED TO %s (%c)\n",
			    HostP->Mapping[OldUnit-1].Name,OldLink+'A',
			    HostP->Mapping[ThisUnit-1].Name,ThisLink+'A');
	    }
	  }
	  if ( NewUnit == HOST_ID )
	  {
	    rio_dprintk (RIO_DEBUG_ROUTE, "MARKING HOST (%c) CONNECTED TO %s (%c)\n",
				NewLink+'A',MyName,ThisLink+'A');
	    HostP->Topology[NewLink].Unit = ThisUnit;
	    HostP->Topology[NewLink].Link = ThisLink;
	  }
	  else if ( NewUnit <= MAX_RUP )
	  {
	    rio_dprintk (RIO_DEBUG_ROUTE, "MARKING RTA %s (%c) CONNECTED TO %s (%c)\n",
	      HostP->Mapping[NewUnit-1].Name,NewLink+'A',MyName,ThisLink+'A');
	    HostP->Mapping[NewUnit-1].Topology[NewLink].Unit=ThisUnit;
	    HostP->Mapping[NewUnit-1].Topology[NewLink].Link=ThisLink;
	  }
	}
	RIOSetChange(p);
	RIOCheckIsolated(p, HostP, OldUnit );
      }
    }
    return TRUE;
  }

  /*
  ** The only other command we recognise is a route_request command
  */
  if ( RBYTE(PktCmdP->Command) != ROUTE_REQUEST )
  {
    rio_dprintk (RIO_DEBUG_ROUTE, "Unknown command %d received on rup %d host %d ROUTE_RUP\n", 
	   RBYTE(PktCmdP->Command),Rup,(int)HostP);
    return TRUE;
  }
      
  RtaUniq = (RBYTE(PktCmdP->UniqNum[0])) +
	    (RBYTE(PktCmdP->UniqNum[1]) << 8) +
	    (RBYTE(PktCmdP->UniqNum[2]) << 16) +
	    (RBYTE(PktCmdP->UniqNum[3]) << 24);

  /*
  ** Determine if 8 or 16 port RTA
  */
  RtaType = GetUnitType(RtaUniq);

  rio_dprintk (RIO_DEBUG_ROUTE, "Received a request for an ID for serial number %x\n", RtaUniq);

  Mod = RBYTE(PktCmdP->ModuleTypes);
  Mod1 = LONYBLE(Mod);
  if (RtaType == TYPE_RTA16)
  {
    /*
    ** Only one ident is set for a 16 port RTA. To make compatible
    ** with 8 port, set 2nd ident in Mod2 to the same as Mod1.
    */
    Mod2 = Mod1;
    rio_dprintk (RIO_DEBUG_ROUTE, "Backplane type is %s (all ports)\n",
     p->RIOModuleTypes[Mod1].Name);
  }
  else
  {
    Mod2 = HINYBLE(Mod);
    rio_dprintk (RIO_DEBUG_ROUTE, "Module types are %s (ports 0-3) and %s (ports 4-7)\n",
     p->RIOModuleTypes[Mod1].Name, p->RIOModuleTypes[Mod2].Name);
  }

  if ( RtaUniq == 0xffffffff )
  {
      ShowPacket( DBG_SPECIAL, PacketP );
  }

  /*
  ** try to unhook a command block from the command free list.
  */
  if ( !(CmdBlkP = RIOGetCmdBlk()) )
  {
    rio_dprintk (RIO_DEBUG_ROUTE, "No command blocks to route RTA! come back later.\n");
    return 0;
  }

  /*
  ** Fill in the default info on the command block
  */
  CmdBlkP->Packet.dest_unit = Rup;
  CmdBlkP->Packet.dest_port = ROUTE_RUP;
  CmdBlkP->Packet.src_unit = HOST_ID;
  CmdBlkP->Packet.src_port = ROUTE_RUP;
  CmdBlkP->Packet.len = PKT_CMD_BIT | 1;
  CmdBlkP->PreFuncP = CmdBlkP->PostFuncP = NULL;
  PktReplyP = (struct PktCmd_M *)CmdBlkP->Packet.data;

  if (! RIOBootOk(p, HostP, RtaUniq))
  {
    rio_dprintk (RIO_DEBUG_ROUTE, "RTA %x tried to get an ID, but does not belong - FOAD it!\n",
	  RtaUniq);
    PktReplyP->Command = ROUTE_FOAD;
    HostP->Copy("RT_FOAD", PktReplyP->CommandText, 7);
    RIOQueueCmdBlk(HostP, Rup, CmdBlkP);
    return TRUE;
  }

  /*
  ** Check to see if the RTA is configured for this host
  */
  for ( ThisUnit=0; ThisUnit<MAX_RUP; ThisUnit++ )
  {
    rio_dprintk (RIO_DEBUG_ROUTE, "Entry %d Flags=%s %s UniqueNum=0x%x\n",
			ThisUnit,
			HostP->Mapping[ThisUnit].Flags & SLOT_IN_USE ?
					    "Slot-In-Use":"Not In Use",
			HostP->Mapping[ThisUnit].Flags & SLOT_TENTATIVE ? 
					    "Slot-Tentative":"Not Tentative",
			HostP->Mapping[ThisUnit].RtaUniqueNum);

    /*
    ** We have an entry for it.
    */
    if ( (HostP->Mapping[ThisUnit].Flags & (SLOT_IN_USE | SLOT_TENTATIVE)) &&
         (HostP->Mapping[ThisUnit].RtaUniqueNum == RtaUniq) )
    {
      if (RtaType == TYPE_RTA16)
      {
	  ThisUnit2 = HostP->Mapping[ThisUnit].ID2 - 1;
          rio_dprintk (RIO_DEBUG_ROUTE, "Found unit 0x%x at slots %d+%d\n",
					    RtaUniq,ThisUnit,ThisUnit2);
      }
      else
          rio_dprintk (RIO_DEBUG_ROUTE, "Found unit 0x%x at slot %d\n",
					    RtaUniq,ThisUnit);
      /*
      ** If we have no knowledge of booting it, then the host has
      ** been re-booted, and so we must kill the RTA, so that it
      ** will be booted again (potentially with new bins)
      ** and it will then re-ask for an ID, which we will service.
      */
      if ( (HostP->Mapping[ThisUnit].Flags & SLOT_IN_USE) && 
	  !(HostP->Mapping[ThisUnit].Flags & RTA_BOOTED) )
      {
	if ( !(HostP->Mapping[ThisUnit].Flags & MSG_DONE) )
	{
	    if ( !p->RIONoMessage )
	        cprintf("RTA '%s' is being updated.\n",HostP->Mapping[ThisUnit].Name);
	    HostP->Mapping[ThisUnit].Flags |= MSG_DONE;
	}
	PktReplyP->Command = ROUTE_FOAD;
	HostP->Copy("RT_FOAD",PktReplyP->CommandText,7);
	RIOQueueCmdBlk(HostP, Rup, CmdBlkP);
	return TRUE;
      }

      /*
      ** Send the ID (entry) to this RTA. The ID number is implicit as
      ** the offset into the table. It is worth noting at this stage
      ** that offset zero in the table contains the entries for the
      ** RTA with ID 1!!!!
      */
      PktReplyP->Command = ROUTE_ALLOCATE;
      PktReplyP->IDNum   = ThisUnit+1;
      if (RtaType == TYPE_RTA16)
      {
        if (HostP->Mapping[ThisUnit].Flags & SLOT_IN_USE)
	    /*
	    ** Adjust the phb and tx pkt dest_units for 2nd block of 8
	    ** only if the RTA has ports associated (SLOT_IN_USE)
	    */
	    RIOFixPhbs(p, HostP, ThisUnit2);
	    PktReplyP->IDNum2  = ThisUnit2+1;
	    rio_dprintk (RIO_DEBUG_ROUTE, "RTA '%s' has been allocated IDs %d+%d\n",
	          HostP->Mapping[ThisUnit].Name, PktReplyP->IDNum, PktReplyP->IDNum2);
      }
      else
      {
	    PktReplyP->IDNum2 = ROUTE_NO_ID;
	    rio_dprintk (RIO_DEBUG_ROUTE, "RTA '%s' has been allocated ID %d\n",
	          HostP->Mapping[ThisUnit].Name,PktReplyP->IDNum);
      }
      HostP->Copy("RT_ALLOCAT",PktReplyP->CommandText,10);

      RIOQueueCmdBlk( HostP, Rup, CmdBlkP);

      /*
      ** If this is a freshly booted RTA, then we need to re-open
      ** the ports, if any where open, so that data may once more
      ** flow around the system!
      */
      if ( (HostP->Mapping[ThisUnit].Flags & RTA_NEWBOOT) &&
	   (HostP->Mapping[ThisUnit].SysPort != NO_PORT) )
      {
	/*
	** look at the ports associated with this beast and
	** see if any where open. If they was, then re-open
	** them, using the info from the tty flags.
	*/
	for ( port=0; port<PORTS_PER_RTA; port++ )
	{
	  PortP = p->RIOPortp[port+HostP->Mapping[ThisUnit].SysPort];
	  if ( PortP->State & (RIO_MOPEN|RIO_LOPEN) )
	  {
	    rio_dprintk (RIO_DEBUG_ROUTE, "Re-opened this port\n");
	    rio_spin_lock_irqsave(&PortP->portSem, flags);
	    PortP->MagicFlags |= MAGIC_REBOOT;
	    rio_spin_unlock_irqrestore(&PortP->portSem, flags);
	  }
	}
	if (RtaType == TYPE_RTA16)
	{
	  for ( port=0; port<PORTS_PER_RTA; port++ )
	  {
	    PortP = p->RIOPortp[port+HostP->Mapping[ThisUnit2].SysPort];
	    if ( PortP->State & (RIO_MOPEN|RIO_LOPEN) )
	    {
	      rio_dprintk (RIO_DEBUG_ROUTE, "Re-opened this port\n");
	      rio_spin_lock_irqsave(&PortP->portSem, flags);
	      PortP->MagicFlags |= MAGIC_REBOOT;
	      rio_spin_unlock_irqrestore(&PortP->portSem, flags);
	    }
	  }
	}
      }

      /*
      ** keep a copy of the module types!
      */
      HostP->UnixRups[ThisUnit].ModTypes = Mod;
      if (RtaType == TYPE_RTA16)
	      HostP->UnixRups[ThisUnit2].ModTypes = Mod;

      /*
      ** If either of the modules on this unit is read-only or write-only
      ** or none-xprint, then we need to transfer that info over to the
      ** relevant ports.
      */
      if ( HostP->Mapping[ThisUnit].SysPort != NO_PORT )
      {
        for ( port=0; port<PORTS_PER_MODULE; port++ )
	{
	  p->RIOPortp[port+HostP->Mapping[ThisUnit].SysPort]->Config &= ~RIO_NOMASK;
	  p->RIOPortp[port+HostP->Mapping[ThisUnit].SysPort]->Config |=
	   p->RIOModuleTypes[Mod1].Flags[port];
	  p->RIOPortp[port+PORTS_PER_MODULE+HostP->Mapping[ThisUnit].SysPort]->Config &= ~RIO_NOMASK;
	  p->RIOPortp[port+PORTS_PER_MODULE+HostP->Mapping[ThisUnit].SysPort]->Config |= p->RIOModuleTypes[Mod2].Flags[port];
	}
	if (RtaType == TYPE_RTA16)
	{
          for ( port=0; port<PORTS_PER_MODULE; port++ )
	  {
	    p->RIOPortp[port+HostP->Mapping[ThisUnit2].SysPort]->Config &= ~RIO_NOMASK;
	    p->RIOPortp[port+HostP->Mapping[ThisUnit2].SysPort]->Config |= p->RIOModuleTypes[Mod1].Flags[port];
	    p->RIOPortp[port+PORTS_PER_MODULE+HostP->Mapping[ThisUnit2].SysPort]->Config &= ~RIO_NOMASK;
	    p->RIOPortp[port+PORTS_PER_MODULE+HostP->Mapping[ThisUnit2].SysPort]->Config |= p->RIOModuleTypes[Mod2].Flags[port];
          }
	}
      }

      /*
      ** Job done, get on with the interrupts!
      */
      return TRUE;
    }
  }
  /*
  ** There is no table entry for this RTA at all.
  **
  ** Lets check to see if we actually booted this unit - if not,
  ** then we reset it and it will go round the loop of being booted
  ** we can then worry about trying to fit it into the table.
  */
  for ( ThisUnit=0; ThisUnit<HostP->NumExtraBooted; ThisUnit++ )
    if ( HostP->ExtraUnits[ThisUnit] == RtaUniq )
      break;
  if ( ThisUnit == HostP->NumExtraBooted && ThisUnit != MAX_EXTRA_UNITS )
  {
    /*
    ** if the unit wasn't in the table, and the table wasn't full, then
    ** we reset the unit, because we didn't boot it.
    ** However, if the table is full, it could be that we did boot
    ** this unit, and so we won't reboot it, because it isn't really
    ** all that disasterous to keep the old bins in most cases. This
    ** is a rather tacky feature, but we are on the edge of reallity
    ** here, because the implication is that someone has connected
    ** 16+MAX_EXTRA_UNITS onto one host.
    */
    static int UnknownMesgDone = 0;

    if ( !UnknownMesgDone )
    {
	if (! p->RIONoMessage)
	    cprintf("One or more unknown RTAs are being updated.\n");
	UnknownMesgDone = 1;
    }

    PktReplyP->Command = ROUTE_FOAD;
    HostP->Copy("RT_FOAD",PktReplyP->CommandText,7);
  }
  else
  {
    /*
    ** we did boot it (as an extra), and there may now be a table
    ** slot free (because of a delete), so we will try to make
    ** a tentative entry for it, so that the configurator can see it
    ** and fill in the details for us.
    */
    if (RtaType == TYPE_RTA16)
    {
	if (RIOFindFreeID(p, HostP, &ThisUnit, &ThisUnit2) == 0)
	{
	    RIODefaultName(p, HostP, ThisUnit);
	    FillSlot(ThisUnit, ThisUnit2, RtaUniq, HostP);
	}
    }
    else
    {
	if (RIOFindFreeID(p, HostP, &ThisUnit, NULL) == 0)
	{
	    RIODefaultName(p, HostP, ThisUnit);
	    FillSlot(ThisUnit, 0, RtaUniq, HostP);
	}
    }
    PktReplyP->Command = ROUTE_USED;
    HostP->Copy("RT_USED",PktReplyP->CommandText,7);
  }
  RIOQueueCmdBlk( HostP, Rup, CmdBlkP);
  return TRUE;
}


void
RIOFixPhbs(p, HostP, unit)
struct rio_info *p;
struct Host *HostP;
uint unit;
{
	ushort			link, port;
	struct Port		*PortP;
	unsigned long flags;
	int PortN = HostP->Mapping[unit].SysPort;

	rio_dprintk (RIO_DEBUG_ROUTE, "RIOFixPhbs unit %d sysport %d\n", unit, PortN);

	if (PortN != -1) {
		ushort		dest_unit = HostP->Mapping[unit].ID2;

		/*
		** Get the link number used for the 1st 8 phbs on this unit.
		*/
		PortP = p->RIOPortp[HostP->Mapping[dest_unit - 1].SysPort];

		link = RWORD(PortP->PhbP->link);

		for (port = 0; port < PORTS_PER_RTA; port++, PortN++) {
			ushort		dest_port = port + 8;
#if 0
			uint		PktInt;
#endif
			WORD		*TxPktP;
			PKT		*Pkt;

			PortP = p->RIOPortp[PortN];

			rio_spin_lock_irqsave(&PortP->portSem, flags);
			/*
			** If RTA is not powered on, the tx packets will be
			** unset, so go no further.
			*/
			if (PortP->TxStart == 0) {
					rio_dprintk (RIO_DEBUG_ROUTE, "Tx pkts not set up yet\n");
					rio_spin_unlock_irqrestore(&PortP->portSem, flags);
					break;
			}

			/*
			** For the second slot of a 16 port RTA, the driver needs to
			** sort out the phb to port mappings. The dest_unit for this
			** group of 8 phbs is set to the dest_unit of the accompanying
			** 8 port block. The dest_port of the second unit is set to
			** be in the range 8-15 (i.e. 8 is added). Thus, for a 16 port
			** RTA with IDs 5 and 6, traffic bound for port 6 of unit 6
			** (being the second map ID) will be sent to dest_unit 5, port
			** 14. When this RTA is deleted, dest_unit for ID 6 will be
			** restored, and the dest_port will be reduced by 8.
			** Transmit packets also have a destination field which needs
			** adjusting in the same manner.
			** Note that the unit/port bytes in 'dest' are swapped.
			** We also need to adjust the phb and rup link numbers for the
			** second block of 8 ttys.
			*/
			for (TxPktP = PortP->TxStart; TxPktP <= PortP->TxEnd; TxPktP++) {
				/*
				** *TxPktP is the pointer to the transmit packet on the host
				** card. This needs to be translated into a 32 bit pointer
				** so it can be accessed from the driver.
				*/
				Pkt = (PKT *) RIO_PTR(HostP->Caddr,RINDW(TxPktP));

				/*
				** If the packet is used, reset it.
				*/
				Pkt = (PKT *)((uint)Pkt & ~PKT_IN_USE);
				WBYTE(Pkt->dest_unit, dest_unit);
				WBYTE(Pkt->dest_port, dest_port);
			}
			rio_dprintk (RIO_DEBUG_ROUTE, "phb dest: Old %x:%x New %x:%x\n",
					RWORD(PortP->PhbP->destination) & 0xff,
					(RWORD(PortP->PhbP->destination) >> 8) & 0xff,
					dest_unit, dest_port);
			WWORD(PortP->PhbP->destination, dest_unit + (dest_port << 8));
			WWORD(PortP->PhbP->link, link);

			rio_spin_unlock_irqrestore(&PortP->portSem, flags);
		}
		/*
		** Now make sure the range of ports to be serviced includes
		** the 2nd 8 on this 16 port RTA.
		*/
		if (link > 3) return;
		if (((unit * 8) + 7) > RWORD(HostP->LinkStrP[link].last_port)) {
			rio_dprintk (RIO_DEBUG_ROUTE, "last port on host link %d: %d\n", link, (unit * 8) + 7);
			WWORD(HostP->LinkStrP[link].last_port, (unit * 8) + 7);
		}
	}
}

/*
** Check to see if the new disconnection has isolated this unit.
** If it has, then invalidate all its link information, and tell
** the world about it. This is done to ensure that the configurator
** only gets up-to-date information about what is going on.
*/
static int
RIOCheckIsolated(p, HostP, UnitId)
struct rio_info *	p;
struct Host *HostP;
uint UnitId;
{
	unsigned long flags;
	rio_spin_lock_irqsave(&HostP->HostLock, flags);

#ifdef CHECK
	CheckHostP( HostP );
	CheckUnitId( UnitId );
#endif
	if ( RIOCheck( HostP, UnitId ) ) {
		rio_dprintk (RIO_DEBUG_ROUTE, "Unit %d is NOT isolated\n", UnitId);
		rio_spin_unlock_irqrestore(&HostP->HostLock, flags);
		return(0);
	}

	RIOIsolate(p, HostP, UnitId );
	RIOSetChange(p);
	rio_spin_unlock_irqrestore(&HostP->HostLock, flags);
	return 1;
}

/*
** Invalidate all the link interconnectivity of this unit, and of
** all the units attached to it. This will mean that the entire
** subnet will re-introduce itself.
*/
static int
RIOIsolate(p, HostP, UnitId)
struct rio_info *	p;
struct Host *		HostP;
uint UnitId; 
{
	uint link, unit;

#ifdef CHECK
	CheckHostP( HostP );
	CheckUnitId( UnitId );
#endif
	UnitId--;		/* this trick relies on the Unit Id being UNSIGNED! */

	if ( UnitId >= MAX_RUP )	/* dontcha just lurv unsigned maths! */
		return(0);

	if ( HostP->Mapping[UnitId].Flags & BEEN_HERE )
		return(0);

	HostP->Mapping[UnitId].Flags |= BEEN_HERE;

	if ( p->RIOPrintDisabled == DO_PRINT )
		rio_dprintk (RIO_DEBUG_ROUTE, "RIOMesgIsolated %s", HostP->Mapping[UnitId].Name);

	for ( link=0; link<LINKS_PER_UNIT; link++) {
		unit = HostP->Mapping[UnitId].Topology[link].Unit;
		HostP->Mapping[UnitId].Topology[link].Unit = ROUTE_DISCONNECT;
		HostP->Mapping[UnitId].Topology[link].Link = NO_LINK;
		RIOIsolate(p, HostP, unit );
	}
	HostP->Mapping[UnitId].Flags &= ~BEEN_HERE;
	return 1;
}

static int
RIOCheck(HostP, UnitId)
struct Host *HostP;
uint UnitId;
{
  unsigned char link;

#ifdef CHECK
	CheckHostP( HostP );
	CheckUnitId( UnitId );
#endif
/* 	rio_dprint(RIO_DEBUG_ROUTE, ("Check to see if unit %d has a route to the host\n",UnitId)); */
	rio_dprintk (RIO_DEBUG_ROUTE, "RIOCheck : UnitID = %d\n", UnitId);

	if ( UnitId == HOST_ID ) {
		/* rio_dprint(RIO_DEBUG_ROUTE, ("Unit %d is NOT isolated - it IS the host!\n", UnitId)); */
		return 1;
	}

	UnitId--;

	if ( UnitId >= MAX_RUP ) {
		/* rio_dprint(RIO_DEBUG_ROUTE, ("Unit %d - ignored.\n", UnitId)); */
		return 0;
	}

	for ( link=0; link<LINKS_PER_UNIT; link++ ) {
		if ( HostP->Mapping[UnitId].Topology[link].Unit==HOST_ID ) {
			/* rio_dprint(RIO_DEBUG_ROUTE, ("Unit %d is connected directly to host via link (%c).\n", 
						UnitId, 'A'+link)); */
			return 1;
		}
	}

	if ( HostP->Mapping[UnitId].Flags & BEEN_HERE ) {
		/* rio_dprint(RIO_DEBUG_ROUTE, ("Been to Unit %d before - ignoring\n", UnitId)); */
		return 0;
	}

	HostP->Mapping[UnitId].Flags |= BEEN_HERE;

	for ( link=0; link < LINKS_PER_UNIT; link++ ) {
		/* rio_dprint(RIO_DEBUG_ROUTE, ("Unit %d check link (%c)\n", UnitId,'A'+link)); */
		if ( RIOCheck( HostP, HostP->Mapping[UnitId].Topology[link].Unit ) ) {
			/* rio_dprint(RIO_DEBUG_ROUTE, ("Unit %d is connected to something that knows the host via link (%c)\n", UnitId,link+'A')); */
			HostP->Mapping[UnitId].Flags &= ~BEEN_HERE;
			return 1;
		}
	}

	HostP->Mapping[UnitId].Flags &= ~BEEN_HERE;

	/* rio_dprint(RIO_DEBUG_ROUTE, ("Unit %d DOESNT KNOW THE HOST!\n", UnitId)); */
	
	return 0;
}

/*
** Returns the type of unit (host, 16/8 port RTA)
*/

uint
GetUnitType(Uniq)
uint Uniq;
{
	switch ( (Uniq >> 28) & 0xf)
	{
		case RIO_AT:
		case RIO_MCA:
		case RIO_EISA:
		case RIO_PCI:
			rio_dprintk (RIO_DEBUG_ROUTE, "Unit type: Host\n");
			return(TYPE_HOST);
		case RIO_RTA_16:
			rio_dprintk (RIO_DEBUG_ROUTE, "Unit type: 16 port RTA\n");
			return(TYPE_RTA16);
		case RIO_RTA:
			rio_dprintk (RIO_DEBUG_ROUTE, "Unit type: 8 port RTA\n");
			return(TYPE_RTA8);
		default :
			rio_dprintk (RIO_DEBUG_ROUTE, "Unit type: Unrecognised\n");
			return(99);
	}
}

int
RIOSetChange(p)
struct rio_info *	p;
{
	if ( p->RIOQuickCheck != NOT_CHANGED )
		return(0);
	p->RIOQuickCheck = CHANGED;
	if ( p->RIOSignalProcess ) {
		rio_dprintk (RIO_DEBUG_ROUTE, "Send SIG-HUP");
		/*
		psignal( RIOSignalProcess, SIGHUP );
		*/
	}
	return(0);
}

static void
RIOConCon(p, HostP, FromId, FromLink, ToId, ToLink, Change)
struct rio_info *	p;
struct Host *HostP;
uint FromId;
uint FromLink;
uint ToId;
uint ToLink;
int Change; 
{
    char *FromName;
    char *FromType;
    char *ToName;
    char *ToType;
    unsigned int tp;

/*
** 15.10.1998 ARG - ESIL 0759
** (Part) fix for port being trashed when opened whilst RTA "disconnected"
**
** What's this doing in here anyway ?
** It was causing the port to be 'unmapped' if opened whilst RTA "disconnected"
**
** 09.12.1998 ARG - ESIL 0776 - part fix
** Okay, We've found out what this was all about now !
** Someone had botched this to use RIOHalted to indicated the number of RTAs
** 'disconnected'. The value in RIOHalted was then being used in the
** 'RIO_QUICK_CHECK' ioctl. A none zero value indicating that a least one RTA
** is 'disconnected'. The change was put in to satisfy a customer's needs.
** Having taken this bit of code out 'RIO_QUICK_CHECK' now no longer works for
** the customer.
**
    if (Change == CONNECT) {
		if (p->RIOHalted) p->RIOHalted --;
	 }
	 else {
		p->RIOHalted ++;
	 }
**
** So - we need to implement it slightly differently - a new member of the
** rio_info struct - RIORtaDisCons (RIO RTA connections) keeps track of RTA
** connections and disconnections. 
*/
    if (Change == CONNECT) {
		if (p->RIORtaDisCons) p->RIORtaDisCons--;
	 }
	 else {
		p->RIORtaDisCons++;
	 }

    if ( p->RIOPrintDisabled == DONT_PRINT )
		return;

    if ( FromId > ToId ) {
		tp = FromId;
		FromId = ToId;
		ToId = tp;
		tp = FromLink;
		FromLink = ToLink;
		ToLink = tp;
    }

    FromName = FromId ? HostP->Mapping[FromId-1].Name : HostP->Name;
    FromType = FromId ? "RTA" : "HOST";
    ToName = ToId ? HostP->Mapping[ToId-1].Name : HostP->Name;
    ToType = ToId ? "RTA" : "HOST";

    rio_dprintk (RIO_DEBUG_ROUTE, "Link between %s '%s' (%c) and %s '%s' (%c) %s.\n",
			    FromType, FromName, 'A'+FromLink,
			    ToType,   ToName,   'A'+ToLink,
			    (Change==CONNECT) ? "established" : "disconnected");
    cprintf("Link between %s '%s' (%c) and %s '%s' (%c) %s.\n",
			    FromType, FromName, 'A'+FromLink,
			    ToType,   ToName,   'A'+ToLink,
			    (Change==CONNECT) ? "established" : "disconnected");
}

/*
** RIORemoveFromSavedTable :
**
** Delete and RTA entry from the saved table given to us
** by the configuration program.
*/
static int
RIORemoveFromSavedTable(struct rio_info *p, struct Map *pMap)
{
    int		entry;

    /*
    ** We loop for all entries even after finding an entry and
    ** zeroing it because we may have two entries to delete if
    ** it's a 16 port RTA.
    */
    for (entry = 0; entry < TOTAL_MAP_ENTRIES; entry++)
    {
	if (p->RIOSavedTable[entry].RtaUniqueNum == pMap->RtaUniqueNum)
	{
	    bzero((caddr_t)&p->RIOSavedTable[entry], sizeof(struct Map));
	}
    }
    return 0;
}


/*
** RIOCheckDisconnected :
**
** Scan the unit links to and return zero if the unit is completely
** disconnected.
*/
static int
RIOFreeDisconnected(struct rio_info *p, struct Host *HostP, int unit)
{
    int		link;


    rio_dprintk (RIO_DEBUG_ROUTE, "RIOFreeDisconnect unit %d\n", unit);
    /*
    ** If the slot is tentative and does not belong to the
    ** second half of a 16 port RTA then scan to see if
    ** is disconnected.
    */
    for (link = 0; link < LINKS_PER_UNIT; link++)
    {
	if (HostP->Mapping[unit].Topology[link].Unit != ROUTE_DISCONNECT)
	    break;
    }

    /*
    ** If not all links are disconnected then we can forget about it.
    */
    if (link < LINKS_PER_UNIT)
	    return 1;

#if NEED_TO_FIX_THIS
    /* Ok so all the links are disconnected. But we may have only just
    ** made this slot tentative and not yet received a topology update.
    ** Lets check how long ago we made it tentative.
    */
    rio_dprintk (RIO_DEBUG_ROUTE, "Just about to check LBOLT on entry %d\n", unit);
    if (drv_getparm(LBOLT, (ulong_t *) &current_time))
        rio_dprintk (RIO_DEBUG_ROUTE, "drv_getparm(LBOLT,....) Failed.\n");

    elapse_time = current_time - TentTime[unit];
    rio_dprintk (RIO_DEBUG_ROUTE, "elapse %d = current %d - tent %d (%d usec)\n",
        elapse_time, current_time, TentTime[unit], drv_hztousec(elapse_time));
    if (drv_hztousec(elapse_time) < WAIT_TO_FINISH)
    {
      rio_dprintk (RIO_DEBUG_ROUTE, "Skipping slot %d, not timed out yet %d\n",
            unit, drv_hztousec(elapse_time));
        return 1;
    }
#endif

    /*
    ** We have found an usable slot.
    ** If it is half of a 16 port RTA then delete the other half.
    */
    if (HostP->Mapping[unit].ID2 != 0)
    {
	int nOther = (HostP->Mapping[unit].ID2) -1;

	rio_dprintk (RIO_DEBUG_ROUTE, "RioFreedis second slot %d.\n", nOther);
	bzero((caddr_t)&HostP->Mapping[nOther], sizeof(struct Map));
    }
    RIORemoveFromSavedTable(p, &HostP->Mapping[unit]);

    return 0;
}


/*
** RIOFindFreeID :
**
** This function scans the given host table for either one
** or two free unit ID's.
*/
int
RIOFindFreeID(struct rio_info *p, struct Host *HostP, uint *pID1, uint *pID2)
{
    int unit,tempID;

    /*
    ** Initialise the ID's to MAX_RUP.
    ** We do this to make the loop for setting the ID's as simple as
    ** possible.
    */
    *pID1 = MAX_RUP;
    if (pID2 != NULL)
	*pID2 = MAX_RUP;

    /*
    ** Scan all entries of the host mapping table for free slots.
    ** We scan for free slots first and then if that is not successful
    ** we start all over again looking for tentative slots we can re-use.
    */
    for (unit = 0; unit < MAX_RUP; unit++)
    {
	rio_dprintk (RIO_DEBUG_ROUTE, "Scanning unit %d\n",unit);
	/*
	** If the flags are zero then the slot is empty.
	*/
	if (HostP->Mapping[unit].Flags == 0)
	{
	    rio_dprintk (RIO_DEBUG_ROUTE, "      This slot is empty.\n");
	    /*
	    ** If we haven't allocated the first ID then do it now.
	    */
	    if (*pID1 == MAX_RUP)
	    {
		rio_dprintk (RIO_DEBUG_ROUTE, "Make tentative entry for first unit %d\n", unit);
		*pID1 = unit;

		/*
		** If the second ID is not needed then we can return
		** now.
		*/
		if (pID2 == NULL)
		    return 0;
	    }
	    else
	    {
		/*
		** Allocate the second slot and return.
		*/
		rio_dprintk (RIO_DEBUG_ROUTE, "Make tentative entry for second unit %d\n", unit);
		*pID2 = unit;
		return 0;
	    }
	}
    }

    /*
    ** If we manage to come out of the free slot loop then we
    ** need to start all over again looking for tentative slots
    ** that we can re-use.
    */
    rio_dprintk (RIO_DEBUG_ROUTE, "Starting to scan for tentative slots\n");
    for (unit = 0; unit < MAX_RUP; unit++)
    {
	if (((HostP->Mapping[unit].Flags & SLOT_TENTATIVE) ||
	                       (HostP->Mapping[unit].Flags == 0))  && ! 
	   (HostP->Mapping[unit].Flags & RTA16_SECOND_SLOT ))
	{
	    rio_dprintk (RIO_DEBUG_ROUTE, "    Slot %d looks promising.\n",unit);

	    if(unit == *pID1)
	    {
	    	rio_dprintk (RIO_DEBUG_ROUTE, "    No it isn't, its the 1st half\n");
		continue;
	    }

	    /*
	    ** Slot is Tentative or Empty, but not a tentative second 
	    ** slot of a 16 porter.
	    ** Attempt to free up this slot (and its parnter if
	    ** it is a 16 port slot. The second slot will become
	    ** empty after a call to RIOFreeDisconnected so thats why
	    ** we look for empty slots above  as well).
	    */
	    if (HostP->Mapping[unit].Flags != 0) 
	    	if (RIOFreeDisconnected(p, HostP, unit) != 0)
			    continue;
	    /*
	    ** If we haven't allocated the first ID then do it now.
	    */
	    if (*pID1 == MAX_RUP)
	    {
		rio_dprintk (RIO_DEBUG_ROUTE, "Grab tentative entry for first unit %d\n", unit);
		*pID1 = unit;

		/*
		** Clear out this slot now that we intend to use it.
		*/
		bzero(&HostP->Mapping[unit], sizeof(struct Map));

		/*
		** If the second ID is not needed then we can return
		** now.
		*/
		if (pID2 == NULL)
		    return 0;
	    }
	    else
	    {
		/*
		** Allocate the second slot and return.
		*/
		rio_dprintk (RIO_DEBUG_ROUTE, "Grab tentative/empty  entry for second unit %d\n",
		      unit);
		*pID2 = unit;

		/*
		** Clear out this slot now that we intend to use it.
		*/
		bzero(&HostP->Mapping[unit], sizeof(struct Map));

		/* At this point under the right(wrong?) conditions
		** we may have a first unit ID being higher than the
		** second unit ID. This is a bad idea if we are about
		** to fill the slots with a 16 port RTA.
		** Better check and swap them over.
		*/

		if (*pID1 > *pID2)
		{
			rio_dprintk (RIO_DEBUG_ROUTE, "Swapping IDS %d %d\n", *pID1, *pID2);
			tempID = *pID1;
			*pID1 = *pID2;
			*pID2 = tempID;
		}
		return 0;
	    }
	}
    }

    /*
    ** If we manage to get to the end of the second loop then we
    ** can give up and return a failure.
    */
    return 1;
}


/*
** The link switch scenario.
**
** Rta Wun (A) is connected to Tuw (A).
** The tables are all up to date, and the system is OK.
**
** If Wun (A) is now moved to Wun (B) before Wun (A) can
** become disconnected, then the follow happens:
**
** Tuw (A) spots the change of unit:link at the other end
** of its link and Tuw sends a topology packet reflecting
** the change: Tuw (A) now disconnected from Wun (A), and
** this is closely followed by a packet indicating that 
** Tuw (A) is now connected to Wun (B).
**
** Wun (B) will spot that it has now become connected, and
** Wun will send a topology packet, which indicates that
** both Wun (A) and Wun (B) is connected to Tuw (A).
**
** Eventually Wun (A) realises that it is now disconnected
** and Wun will send out a topology packet indicating that
** Wun (A) is now disconnected.
*/