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Hacked the Bus component to permit devices to access the actual memory map (better solution will be maintain two separate maps: one for the CPU and a separate map for device access)

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This commit is contained in:
Jeff Parsons 2016-11-28 13:27:06 -08:00 • committed by Jeff Parsons
commit 375146f6bb
9 changed files with 733 additions and 698 deletions
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218
modules/pdp11/lib/cpustate.js
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@ -271,12 +271,15 @@ CPUStatePDP11.prototype.resetMMU = function()
this.mmuLastMode = 0;
this.mmuMask = 0x3ffff;
this.lastAddr = 0; // this is queried by the Panel when it's not using its own ADDRESS register
this.lastOp = 0; // stores the PC and any auto-incs or auto-decs from the last opcode; used to update MMR1 and MMR2
this.addrLast = 0; // this is queried by the Panel when it's not using its own ADDRESS register
this.opLast = 0; // stores the PC and any auto-incs or auto-decs from the last opcode; used to update MMR1 and MMR2
this.resetIRQs();
if (this.bus) this.setMemoryAccess();
if (this.bus) {
this.setMemoryAccess();
this.addrInvalid = this.bus.getMemorySize(MemoryPDP11.TYPE.RAM);
}
};
/**
@ -356,11 +359,11 @@ CPUStatePDP11.prototype.setMMR0 = function(newMMR0)
if (newMMR0 & PDP11.MMR0.ABORT) {
/*
* If updates to MMR0[1-7], MMR1, and MMR2 are being shut off (ie, MMR0.ABORT bits are transitioning
* from clear to set), then do one final sync with their real-time counterparts in lastOp.
* from clear to set), then do one final sync with their real-time counterparts in opLast.
*/
if (!(this.regMMR0 & PDP11.MMR0.ABORT)) {
this.regMMR1 = (this.lastOp >> 16) & 0xffff;
this.regMMR2 = this.lastOp & 0xffff;
this.regMMR1 = (this.opLast >> 16) & 0xffff;
this.regMMR2 = this.opLast & 0xffff;
}
}
/*
@ -393,10 +396,10 @@ CPUStatePDP11.prototype.getMMR1 = function()
{
/*
* If updates to MMR1 have not been shut off (ie, MMR0.ABORT bits are clear),
* then we are allowed to sync MMR1 with its real-time counterpart in lastOp.
* then we are allowed to sync MMR1 with its real-time counterpart in opLast.
*/
if (!(this.regMMR0 & PDP11.MMR0.ABORT)) {
this.regMMR1 = (this.lastOp >> 16) & 0xffff;
this.regMMR1 = (this.opLast >> 16) & 0xffff;
}
var result = this.regMMR1;
if (result & 0xff00) {
@ -415,10 +418,10 @@ CPUStatePDP11.prototype.getMMR2 = function()
{
/*
* If updates to MMR2 have not been shut off (ie, MMR0.ABORT bits are clear),
* then we are allowed to sync MMR2 with its real-time counterpart in lastOp.
* then we are allowed to sync MMR2 with its real-time counterpart in opLast.
*/
if (!(this.regMMR0 & PDP11.MMR0.ABORT)) {
this.regMMR2 = this.lastOp & 0xffff;
this.regMMR2 = this.opLast & 0xffff;
}
return this.regMMR2;
};
@ -662,7 +665,7 @@ CPUStatePDP11.prototype.setNF = function()
CPUStatePDP11.prototype.getOpcode = function()
{
var pc = this.regsGen[PDP11.REG.PC];
this.lastOp = pc;
this.opLast = pc;
/*
* If PC is unaligned, a BUS trap will be generated, and because it will generate an
* exception, the next line (the equivalent of advancePC(2)) will not be executed, ensuring that
@ -710,7 +713,7 @@ CPUStatePDP11.prototype.getPC = function()
*/
CPUStatePDP11.prototype.getLastAddr = function()
{
return this.lastAddr;
return this.addrLast;
};
/**
@ -721,7 +724,7 @@ CPUStatePDP11.prototype.getLastAddr = function()
*/
CPUStatePDP11.prototype.getLastPC = function()
{
return this.lastOp & 0xffff;
return this.opLast & 0xffff;
};
/**
@ -1365,14 +1368,14 @@ CPUStatePDP11.prototype.trap = function(vector, flag, reason)
* diagnostic (PC 056710), which tests what happens when a misaligned read triggers a BUS trap,
* and that trap then triggers an MMU trap during the first pushWord() below.
*
* One would think it would be fine to zero those bits by setting lastOp to vector alone,
* One would think it would be fine to zero those bits by setting opLast to vector alone,
* and then letting each of the pushWord() calls below shift their own 0xF6 auto-dec value into
* lastOp. When the first pushWord() triggers an MMU trap, we obviously won't get to the second
* opLast. When the first pushWord() triggers an MMU trap, we obviously won't get to the second
* pushWord(), yet the diagnostic expects TWO auto-decs to be recorded. I'm puzzled why the
* hardware apparently indicates TWO auto-decs, if SP wasn't actually decremented twice, but who
* am I to judge.
*/
this.lastOp = vector | 0xf6f60000;
this.opLast = vector | 0xf6f60000;
/*
* Read from kernel D space
@ -1476,7 +1479,7 @@ CPUStatePDP11.prototype.getTrapStatus = function()
/**
* mapUnibus(addr)
*
* If bits 18-21 of addr are all set (which is implied by addr >= BusPDP11.UNIBUS_22BIT aka 0x3C0000),
* If bits 18-21 of addr are all set (which callers check using addr >= BusPDP11.UNIBUS_22BIT aka 0x3C0000),
* then we have a 22-bit address pointing to the top 256Kb range, so if the UNIBUS relocation map is enabled,
* we must pass the lower 18 bits of that address through the map.
*
@ -1532,7 +1535,7 @@ CPUStatePDP11.prototype.mapUnibus = function(addr)
};
/**
* mapVirtualToPhysical(virtualAddress, access)
* mapVirtualToPhysical(addrVirtual, access)
*
* mapVirtualToPhysical() does memory management. It converts a 17-bit I/D virtual address to a
* 22-bit physical address. A real PDP 11/70 memory management unit can be enabled separately
@ -1582,60 +1585,55 @@ CPUStatePDP11.prototype.mapUnibus = function(addr)
* physical address to the next 8Kb page.
*
* @this {CPUStatePDP11}
* @param {number} virtualAddress
* @param {number} addrVirtual
* @param {number} access
* @return {number}
*/
CPUStatePDP11.prototype.mapVirtualToPhysical = function(virtualAddress, access)
CPUStatePDP11.prototype.mapVirtualToPhysical = function(addrVirtual, access)
{
var page, pdr, physicalAddress;
this.assert(!(virtualAddress & ~0x1ffff) && access);
var page, pdr, addr;
/*
* This can happen when the DSTMODE (MAINT) bit of MMR0 is set but *not* the ENABLED bit.
*/
if (!(access & this.mmuEnable)) {
physicalAddress = virtualAddress & 0xffff;
if (physicalAddress >= BusPDP11.IOPAGE_16BIT) {
physicalAddress |= this.addrIOPage;
addr = addrVirtual & 0xffff;
if (addr >= BusPDP11.IOPAGE_16BIT) {
addr |= this.addrIOPage;
}
return physicalAddress;
return addr;
}
page = virtualAddress >> 13;
page = addrVirtual >> 13;
if (!(this.regMMR3 & this.mapMMR3[this.mmuMode])) page &= 7;
pdr = this.mmuPDR[this.mmuMode][page];
physicalAddress = ((this.mmuPAR[this.mmuMode][page] << 6) + (virtualAddress & 0x1fff)) & this.mmuMask;
addr = ((this.mmuPAR[this.mmuMode][page] << 6) + (addrVirtual & 0x1fff)) & this.mmuMask;
if (this.nDisableTraps) return physicalAddress;
if (addr >= BusPDP11.UNIBUS_22BIT) {
addr = this.mapUnibus(addr);
}
if (this.nDisableTraps) return addr;
/*
* This next bit is the weirdness that Paul mentions in the function description above:
*
* As an aside it turns out that it is the memory management unit that does odd address and
* non-existent memory trapping: who knew? :-) I thought these would have been handled at access time.
*
* TEST #122 ("KT BEND") in the "EKBEE1" diagnostic (PC 076060) triggers an ODDADDR error using this
* instruction:
*
* 076356: 005037 140001 CLR @#140001
*
* and it expects that instruction to generate a BUS error rather than an MMU error, so we deal with that
* next. However, the test also claims to check for an NEXM (non-existent memory) error, using this
* instruction:
* TEST #122 ("KT BEND") in the "EKBEE1" diagnostic (PC 076060) triggers a NOMEMORY error
* using this instruction:
*
* 076170: 005037 140100 CLR @#140100
*
* but that error never materializes, so I've NOT included any NEXM checks yet. I assume that any such
* checks would be limited to whatever's recorded in the Memory Size registers (177760), because actually
* checking every physical address at this stage -- even in a real MMU -- seems prohibitively expensive.
* It also triggers an ODDADDR error using this instruction:
*
* TODO: Investigate why the test's NEXM error doesn't occur.
* 076356: 005037 140001 CLR @#140001
*
* These tests exercise the MMU checks that Paul mentions in the function description above.
*/
if ((physicalAddress & 0x1) && !(access & PDP11.ACCESS.BYTE)) {
if (addr >= this.addrInvalid && addr < this.addrIOPage) {
this.regErr |= PDP11.CPUERR.NOMEMORY;
this.trap(PDP11.TRAP.BUS, 0, addr);
}
else if ((addr & 0x1) && !(access & PDP11.ACCESS.BYTE)) {
this.regErr |= PDP11.CPUERR.ODDADDR;
this.trap(PDP11.TRAP.BUS, 0, physicalAddress);
this.trap(PDP11.TRAP.BUS, 0, addr);
}
var newMMR0 = 0;
@ -1679,12 +1677,12 @@ CPUStatePDP11.prototype.mapVirtualToPhysical = function(virtualAddress, access)
*/
if (pdr & PDP11.PDR.ED) {
if (pdr & PDP11.PDR.PLF) {
if ((virtualAddress & 0x1FC0) < ((pdr >> 2) & 0x1FC0)) {
if ((addrVirtual & 0x1FC0) < ((pdr >> 2) & 0x1FC0)) {
newMMR0 |= PDP11.MMR0.ABORT_PL;
}
}
} else {
if ((virtualAddress & 0x1FC0) > ((pdr >> 2) & 0x1FC0)) {
if ((addrVirtual & 0x1FC0) > ((pdr >> 2) & 0x1FC0)) {
newMMR0 |= PDP11.MMR0.ABORT_PL;
}
}
@ -1695,7 +1693,7 @@ CPUStatePDP11.prototype.mapVirtualToPhysical = function(virtualAddress, access)
*/
this.mmuPDR[this.mmuMode][page] = pdr;
if (physicalAddress != ((BusPDP11.IOPAGE_22BIT | PDP11.UNIBUS.MMR0) & this.mmuMask) || this.mmuMode) {
if (addr != ((BusPDP11.IOPAGE_22BIT | PDP11.UNIBUS.MMR0) & this.mmuMask) || this.mmuMode) {
this.mmuLastMode = this.mmuMode;
this.mmuLastPage = page;
}
@ -1721,8 +1719,8 @@ CPUStatePDP11.prototype.mapVirtualToPhysical = function(virtualAddress, access)
/*
* TODO: Review the code below, because the address range seems over-inclusive.
*/
if (physicalAddress < ((BusPDP11.IOPAGE_22BIT | PDP11.UNIBUS.SIPDR0) & this.mmuMask) ||
physicalAddress > ((BusPDP11.IOPAGE_22BIT | PDP11.UNIBUS.UDPAR7 | 0x1) & this.mmuMask)) {
if (addr < ((BusPDP11.IOPAGE_22BIT | PDP11.UNIBUS.SIPDR0) & this.mmuMask) ||
addr > ((BusPDP11.IOPAGE_22BIT | PDP11.UNIBUS.UDPAR7 | 0x1) & this.mmuMask)) {
this.regMMR0 |= PDP11.MMR0.TRAP_MMU;
if (this.regMMR0 & PDP11.MMR0.MMU_TRAPS) {
this.opFlags |= PDP11.OPFLAG.TRAP_MMU;
@ -1730,32 +1728,32 @@ CPUStatePDP11.prototype.mapVirtualToPhysical = function(virtualAddress, access)
}
}
}
return physicalAddress;
return addr;
};
/**
* readByteFromPhysical(physicalAddress)
* readByteFromPhysical(addr)
*
* @this {CPUStatePDP11}
* @param {number} physicalAddress
* @param {number} addr
* @return {number}
*/
CPUStatePDP11.prototype.readByteFromPhysical = function(physicalAddress)
CPUStatePDP11.prototype.readByteFromPhysical = function(addr)
{
return this.bus.getByte(physicalAddress);
return this.bus.getByte(addr);
};
/**
* writeByteToPhysical(physicalAddress, data)
* writeByteToPhysical(addr, data)
*
* @this {CPUStatePDP11}
* @param {number} physicalAddress
* @param {number} addr
* @param {number} data
*/
CPUStatePDP11.prototype.writeByteToPhysical = function(physicalAddress, data)
CPUStatePDP11.prototype.writeByteToPhysical = function(addr, data)
{
if (physicalAddress & 1) this.nStepCycles--;
this.bus.setByte(physicalAddress, data);
if (addr & 1) this.nStepCycles--;
this.bus.setByte(addr, data);
};
/**
@ -1780,11 +1778,11 @@ CPUStatePDP11.prototype.popWord = function()
*/
CPUStatePDP11.prototype.pushWord = function(data, fRed)
{
var virtualAddress = (this.regsGen[6] - 2) & 0xffff;
this.regsGen[6] = virtualAddress; // BSD needs SP updated before any fault :-(
this.lastOp = (this.lastOp & 0xffff) | ((this.lastOp & ~0xffff) << 8) | (0x00f6 << 16);
if (!fRed) this.checkStackLimit(PDP11.ACCESS.WRITE_WORD, -2, virtualAddress);
this.writeWord(virtualAddress, data);
var addrVirtual = (this.regsGen[6] - 2) & 0xffff;
this.regsGen[6] = addrVirtual; // BSD needs SP updated before any fault :-(
this.opLast = (this.opLast & 0xffff) | ((this.opLast & ~0xffff) << 8) | (0x00f6 << 16);
if (!fRed) this.checkStackLimit(PDP11.ACCESS.WRITE_WORD, -2, addrVirtual);
this.writeWord(addrVirtual, data);
};
/**
@ -1835,7 +1833,7 @@ CPUStatePDP11.prototype.pushWord = function(data, fRed)
*/
CPUStatePDP11.prototype.getAddrByMode = function(mode, reg, access)
{
var virtualAddress, step;
var addrVirtual, step;
var addrDSpace = (access & PDP11.ACCESS.VIRT)? 0 : this.addrDSpace;
/*
@ -1868,10 +1866,10 @@ CPUStatePDP11.prototype.getAddrByMode = function(mode, reg, access)
*/
case 2:
step = 2;
virtualAddress = this.regsGen[reg];
if (reg == 6) this.checkStackLimit(access, step, virtualAddress);
addrVirtual = this.regsGen[reg];
if (reg == 6) this.checkStackLimit(access, step, addrVirtual);
if (reg != 7) {
virtualAddress |= addrDSpace;
addrVirtual |= addrDSpace;
if (reg < 6 && (access & PDP11.ACCESS.BYTE)) step = 1;
}
this.nStepCycles -= (2 + 1);
@ -1882,10 +1880,10 @@ CPUStatePDP11.prototype.getAddrByMode = function(mode, reg, access)
*/
case 3:
step = 2;
virtualAddress = this.regsGen[reg];
if (reg != 7) virtualAddress |= addrDSpace;
virtualAddress = this.readWord(virtualAddress);
virtualAddress |= addrDSpace;
addrVirtual = this.regsGen[reg];
if (reg != 7) addrVirtual |= addrDSpace;
addrVirtual = this.readWord(addrVirtual);
addrVirtual |= addrDSpace;
this.nStepCycles -= (5 + 2);
break;
@ -1895,9 +1893,9 @@ CPUStatePDP11.prototype.getAddrByMode = function(mode, reg, access)
case 4:
step = -2;
if (reg < 6 && (access & PDP11.ACCESS.BYTE)) step = -1;
virtualAddress = (this.regsGen[reg] + step) & 0xffff;
if (reg == 6) this.checkStackLimit(access, step, virtualAddress);
if (reg != 7) virtualAddress |= addrDSpace;
addrVirtual = (this.regsGen[reg] + step) & 0xffff;
if (reg == 6) this.checkStackLimit(access, step, addrVirtual);
if (reg != 7) addrVirtual |= addrDSpace;
this.nStepCycles -= (3 + 1);
break;
@ -1906,9 +1904,9 @@ CPUStatePDP11.prototype.getAddrByMode = function(mode, reg, access)
*/
case 5:
step = -2;
virtualAddress = (this.regsGen[reg] - 2) & 0xffff;
if (reg != 7) virtualAddress |= addrDSpace;
virtualAddress = this.readWord(virtualAddress) | addrDSpace;
addrVirtual = (this.regsGen[reg] - 2) & 0xffff;
if (reg != 7) addrVirtual |= addrDSpace;
addrVirtual = this.readWord(addrVirtual) | addrDSpace;
this.nStepCycles -= (6 + 2);
break;
@ -1916,27 +1914,27 @@ CPUStatePDP11.prototype.getAddrByMode = function(mode, reg, access)
* Mode 6: d(R)
*/
case 6:
virtualAddress = this.readWord(this.advancePC(2));
virtualAddress = (virtualAddress + this.regsGen[reg]) & 0xffff;
if (reg == 6) this.checkStackLimit(access, 0, virtualAddress);
addrVirtual = this.readWord(this.advancePC(2));
addrVirtual = (addrVirtual + this.regsGen[reg]) & 0xffff;
if (reg == 6) this.checkStackLimit(access, 0, addrVirtual);
this.nStepCycles -= (4 + 2);
return virtualAddress | addrDSpace;
return addrVirtual | addrDSpace;
/*
* Mode 7: @d(R)
*/
case 7:
virtualAddress = this.readWord(this.advancePC(2));
virtualAddress = (virtualAddress + this.regsGen[reg]) & 0xffff;
virtualAddress = this.readWord(virtualAddress | this.addrDSpace);
addrVirtual = this.readWord(this.advancePC(2));
addrVirtual = (addrVirtual + this.regsGen[reg]) & 0xffff;
addrVirtual = this.readWord(addrVirtual | this.addrDSpace);
this.nStepCycles -= (7 + 3);
return virtualAddress | addrDSpace;
return addrVirtual | addrDSpace;
}
this.regsGen[reg] = (this.regsGen[reg] + step) & 0xffff;
this.lastOp = (this.lastOp & 0xffff) | ((this.lastOp & ~0xffff) << 8) | ((((step << 3) & 0xf8) | reg) << 16);
this.opLast = (this.opLast & 0xffff) | ((this.opLast & ~0xffff) << 8) | ((((step << 3) & 0xf8) | reg) << 16);
return virtualAddress;
return addrVirtual;
};
/**
@ -2127,59 +2125,59 @@ CPUStatePDP11.prototype.getVirtualAddrByMode = function(mode, reg, access)
};
/**
* readWordFromPhysical(physicalAddress)
* readWordFromPhysical(addr)
*
* This is a handler set up by setMemoryAccess(). All calls should go through readWord().
*
* @this {CPUStatePDP11}
* @param {number} physicalAddress
* @param {number} addr
* @return {number}
*/
CPUStatePDP11.prototype.readWordFromPhysical = function(physicalAddress)
CPUStatePDP11.prototype.readWordFromPhysical = function(addr)
{
return this.bus.getWord(this.lastAddr = physicalAddress);
return this.bus.getWord(this.addrLast = addr);
};
/**
* readWordFromVirtual(virtualAddress)
* readWordFromVirtual(addrVirtual)
*
* This is a handler set up by setMemoryAccess(). All calls should go through readWord().
*
* @this {CPUStatePDP11}
* @param {number} virtualAddress (input address is 17 bit (I&D))
* @param {number} addrVirtual (input address is 17 bit (I&D))
* @return {number}
*/
CPUStatePDP11.prototype.readWordFromVirtual = function(virtualAddress)
CPUStatePDP11.prototype.readWordFromVirtual = function(addrVirtual)
{
return this.bus.getWord(this.lastAddr = this.mapVirtualToPhysical(virtualAddress, PDP11.ACCESS.READ_WORD));
return this.bus.getWord(this.addrLast = this.mapVirtualToPhysical(addrVirtual, PDP11.ACCESS.READ_WORD));
};
/**
* writeWordToPhysical(physicalAddress, data)
* writeWordToPhysical(addr, data)
*
* This is a handler set up by setMemoryAccess(). All calls should go through writeWord().
*
* @this {CPUStatePDP11}
* @param {number} physicalAddress
* @param {number} addr
* @param {number} data
*/
CPUStatePDP11.prototype.writeWordToPhysical = function(physicalAddress, data)
CPUStatePDP11.prototype.writeWordToPhysical = function(addr, data)
{
this.bus.setWord(this.lastAddr = physicalAddress, data & 0xffff);
this.bus.setWord(this.addrLast = addr, data & 0xffff);
};
/**
* writeWordToVirtual(virtualAddress, data)
* writeWordToVirtual(addrVirtual, data)
*
* This is a handler set up by setMemoryAccess(). All calls should go through writeWord().
*
* @this {CPUStatePDP11}
* @param {number} virtualAddress (input address is 17 bit (I&D))
* @param {number} addrVirtual (input address is 17 bit (I&D))
* @param {number} data
*/
CPUStatePDP11.prototype.writeWordToVirtual = function(virtualAddress, data)
CPUStatePDP11.prototype.writeWordToVirtual = function(addrVirtual, data)
{
this.bus.setWord(this.lastAddr = this.mapVirtualToPhysical(virtualAddress, PDP11.ACCESS.WRITE_WORD), data);
this.bus.setWord(this.addrLast = this.mapVirtualToPhysical(addrVirtual, PDP11.ACCESS.WRITE_WORD), data);
};
/**
@ -2223,7 +2221,7 @@ CPUStatePDP11.prototype.readWordFromPrevSpace = function(opCode, access)
*/
CPUStatePDP11.prototype.writeWordToPrevSpace = function(opCode, access, data)
{
this.lastOp = (this.lastOp & 0xffff) | (0x0016 << 16);
this.opLast = (this.opLast & 0xffff) | (0x0016 << 16);
var reg = this.dstReg = opCode & PDP11.OPREG.MASK;
var mode = this.dstMode = (opCode & PDP11.OPMODE.MASK) >> PDP11.OPMODE.SHIFT;
if (!mode) {