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Some Bus and Video tweaks

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This commit is contained in:
Jeff Parsons 2015-01-27 15:46:22 -08:00 • committed by jeffpar
commit 2637a4ca85
9 changed files with 290 additions and 168 deletions
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120
modules/pcjs/lib/bus.js
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@ -98,19 +98,19 @@ function Bus(parmsBus, cpu, dbg)
*
* iBlock & this.blockMask
*
* While we *could* say that we mask addresses with this.addrMask to simulate "A20 wrap", the simple
* While we *could* say that we mask addresses with this.busMask to simulate "A20 wrap", the simple
* fact is it relieves us from bounds-checking every aMemBlocks index. Address wrapping at the 1Mb
* boundary (ie, the A20 address line) is something we'll have to deal with more carefully on the 80286.
*
* New property Old property Old hard-coded values (when nBusWidth was always 20)
* ------------ ------------ ----------------------------------------------------
* this.addrLimit Bus.ADDR.LIMIT 0xfffff
* this.addrMask N/A N/A
* this.busLimit Bus.ADDR.LIMIT 0xfffff
* this.busMask N/A N/A
* this.blockSize Bus.BLOCK.SIZE 4096
* this.blockLen Bus.BLOCK.LEN (this.blockSize >> 2)
* this.blockShift Bus.BLOCK.SHIFT 12
* this.blockLimit Bus.BLOCK.LIMIT 0xfff
* this.blockTotal Bus.BLOCK.TOTAL ((this.addrLimit + this.blockSize) / this.blockSize) | 0
* this.blockTotal Bus.BLOCK.TOTAL ((this.busLimit + this.blockSize) / this.blockSize) | 0
* this.blockMask Bus.BLOCK.MASK (this.blockTotal - 1) (ie, 0xff)
*
* Note that the blockShift calculation below chooses a 4Kb physical memory block size for a 20-bit bus
@ -123,13 +123,14 @@ function Bus(parmsBus, cpu, dbg)
* memory implementation detail, which should have no bearing on segment or page granularity of any future
* virtual memory implementation.
*/
this.addrLimit = this.addrMask = (1 << this.nBusWidth) - 1;
this.busLimit = this.busMask = (1 << this.nBusWidth) - 1;
this.blockShift = (this.nBusWidth <= 20? 12 : 14);
this.blockSize = 1 << this.blockShift;
this.blockLen = this.blockSize >> 2;
this.blockLimit = this.blockSize - 1;
this.blockTotal = ((this.addrLimit + this.blockSize) / this.blockSize) | 0;
this.blockTotal = ((this.busLimit + this.blockSize) / this.blockSize) | 0;
this.blockMask = this.blockTotal - 1;
this.assert(this.blockTotal <= Bus.BLOCK.MASK);
/*
* Lists of I/O notification functions: aPortInputNotify and aPortOutputNotify are arrays, indexed by
@ -235,6 +236,15 @@ if (BACKTRACK) {
};
}
/*
* scanMemory() records block numbers in bits 0-14, a BackTrack "mod" bit in bit 15, and the block type at bit 16.
*/
Bus.BLOCK = {
MASK: 0x7fff,
BTMOD_SHIFT: 15,
TYPE_SHIFT: 16
};
/**
* initMemory()
*
@ -250,8 +260,8 @@ Bus.prototype.initMemory = function()
var block = this.aMemBlocks[iBlock] = new Memory(addr);
if (DEBUGGER) block.setDebugInfo(this.cpu, this.dbg, addr, this.blockSize);
}
this.cpu.initMemory(this.aMemBlocks, this.addrLimit, this.blockShift, this.blockLimit, this.blockMask);
this.cpu.setAddressMask(this.addrMask);
this.cpu.initMemory(this.aMemBlocks, this.blockShift, this.blockLimit, this.blockMask);
this.cpu.setAddressMask(this.busMask);
};
/**
@ -300,7 +310,7 @@ Bus.prototype.powerUp = function(data, fRepower)
*
* @this {Bus}
* @param {number} addr is the starting physical address of the memory address range
* @param {number} size of the length in bytes of the range; must be a multiple of BLOCK_SIZE
* @param {number} size of the length in bytes of the range; must be a multiple of blockSize
* @param {number} type is one of the Memory.TYPE constants
* @param {Object} [controller] is an optional memory controller component
* @return {boolean} true if successful, false if not
@ -348,27 +358,49 @@ Bus.prototype.cleanMemory = function(addr, size)
};
/**
* scanMemory(addr, size, stats)
* scanMemory(stats, addr, size)
*
* Returns a Stats object for the specified address range with the following properties:
*
* cbTotal: total bytes allocated
* cBlocks: total Memory blocks allocated
* aBlocks: array of allocated Memory block numbers
*
* aBlocks is preallocated to its maximum size, so don't rely on its length; at any given moment,
* only the first cBlocks entries will be valid.
*
* @this {Bus}
* @param {number} [addr]
* @param {number} [size]
* @param {Object} [stats]
* @return {number} bytes allocated
* @param {Object} [stats] previous stats, if any
* @param {number} [addr] starting address of range (0 if none provided)
* @param {number} [size] size of range, in bytes (up to end of address space if none provided)
* @return {Object} updated stats (or new stats if no previous stats provided)
*/
Bus.prototype.scanMemory = function(addr, size, stats)
Bus.prototype.scanMemory = function(stats, addr, size)
{
var cbTotal = 0;
if (addr === undefined) addr = 0;
if (size === undefined) size = (this.addrLimit + 1) - addr;
if (addr == null) addr = 0;
if (size == null) size = (this.busLimit + 1) - addr;
if (stats == null) stats = {cbTotal: 0, cBlocks: 0, aBlocks: new Array(this.blockTotal)};
var iBlock = addr >>> this.blockShift;
var iBlockMax = ((addr + size - 1) >>> this.blockShift);
stats.cbTotal = 0;
stats.cBlocks = 0;
while (iBlock <= iBlockMax) {
var block = this.aMemBlocks[iBlock];
cbTotal += block.size;
stats.cbTotal += block.size;
if (block.size) {
var nBlock = iBlock;
nBlock |= (block.type << Bus.BLOCK.TYPE_SHIFT);
if (BACKTRACK) {
var fMod = block.modBackTrack(false);
if (fMod) nBlock |= (1 << Bus.BLOCK.BTMOD_SHIFT);
}
stats.aBlocks[stats.cBlocks++] = nBlock;
}
iBlock++;
}
return cbTotal;
return stats;
};
/**
@ -379,7 +411,7 @@ Bus.prototype.scanMemory = function(addr, size, stats)
*/
Bus.prototype.getA20 = function()
{
return this.addrLimit == this.addrMask;
return this.busLimit == this.busMask;
};
/**
@ -393,9 +425,9 @@ Bus.prototype.setA20 = function(fEnable)
this.assert(fEnable !== undefined);
if (fEnable !== undefined) {
if (this.nBusWidth > 20) {
var addrMask = (this.addrMask & ~0x100000) | (fEnable? 0x100000 : 0);
if (addrMask != this.addrMask) {
this.addrMask = addrMask;
var addrMask = (this.busMask & ~0x100000) | (fEnable? 0x100000 : 0);
if (addrMask != this.busMask) {
this.busMask = addrMask;
/*
* This callback is required only because the CPU "insists" on using its own memory access functions.
*/
@ -484,7 +516,7 @@ Bus.prototype.removeMemory = function(addr, size)
*/
Bus.prototype.getByte = function(addr)
{
return this.aMemBlocks[(addr & this.addrMask) >> this.blockShift].readByte(addr & this.blockLimit);
return this.aMemBlocks[(addr & this.busMask) >> this.blockShift].readByte(addr & this.blockLimit);
};
/**
@ -498,7 +530,7 @@ Bus.prototype.getByte = function(addr)
*/
Bus.prototype.getByteDirect = function(addr)
{
return this.aMemBlocks[(addr & this.addrMask) >> this.blockShift].readByteDirect(addr & this.blockLimit);
return this.aMemBlocks[(addr & this.busMask) >> this.blockShift].readByteDirect(addr & this.blockLimit);
};
/**
@ -515,9 +547,9 @@ Bus.prototype.getByteDirect = function(addr)
Bus.prototype.getShort = function(addr)
{
var off = addr & this.blockLimit;
var iBlock = (addr & this.addrMask) >> this.blockShift;
var iBlock = (addr & this.busMask) >> this.blockShift;
if (off != this.blockLimit) {
return this.aMemBlocks[iBlock].readWord(off);
return this.aMemBlocks[iBlock].readShort(off);
}
return this.aMemBlocks[iBlock++].readByte(off) | (this.aMemBlocks[iBlock & this.blockMask].readByte(0) << 8);
};
@ -534,9 +566,9 @@ Bus.prototype.getShort = function(addr)
Bus.prototype.getShortDirect = function(addr)
{
var off = addr & this.blockLimit;
var iBlock = (addr & this.addrMask) >> this.blockShift;
var iBlock = (addr & this.busMask) >> this.blockShift;
if (off != this.blockLimit) {
return this.aMemBlocks[iBlock].readWordDirect(off);
return this.aMemBlocks[iBlock].readShortDirect(off);
}
return this.aMemBlocks[iBlock++].readByteDirect(off) | (this.aMemBlocks[iBlock & this.blockMask].readByteDirect(0) << 8);
};
@ -555,7 +587,7 @@ Bus.prototype.getShortDirect = function(addr)
Bus.prototype.getLong = function(addr)
{
var off = addr & this.blockLimit;
var iBlock = (addr & this.addrMask) >> this.blockShift;
var iBlock = (addr & this.busMask) >> this.blockShift;
if (off < this.blockLimit - 2) {
return this.aMemBlocks[iBlock].readLong(off);
}
@ -575,7 +607,7 @@ Bus.prototype.getLong = function(addr)
Bus.prototype.getLongDirect = function(addr)
{
var off = addr & this.blockLimit;
var iBlock = (addr & this.addrMask) >> this.blockShift;
var iBlock = (addr & this.busMask) >> this.blockShift;
if (off < this.blockLimit - 2) {
return this.aMemBlocks[iBlock].readLongDirect(off);
}
@ -595,7 +627,7 @@ Bus.prototype.getLongDirect = function(addr)
*/
Bus.prototype.setByte = function(addr, b)
{
this.aMemBlocks[(addr & this.addrMask) >> this.blockShift].writeByte(addr & this.blockLimit, b & 0xff);
this.aMemBlocks[(addr & this.busMask) >> this.blockShift].writeByte(addr & this.blockLimit, b & 0xff);
};
/**
@ -610,7 +642,7 @@ Bus.prototype.setByte = function(addr, b)
*/
Bus.prototype.setByteDirect = function(addr, b)
{
this.aMemBlocks[(addr & this.addrMask) >> this.blockShift].writeByteDirect(addr & this.blockLimit, b & 0xff);
this.aMemBlocks[(addr & this.busMask) >> this.blockShift].writeByteDirect(addr & this.blockLimit, b & 0xff);
};
/**
@ -627,9 +659,9 @@ Bus.prototype.setByteDirect = function(addr, b)
Bus.prototype.setShort = function(addr, w)
{
var off = addr & this.blockLimit;
var iBlock = (addr & this.addrMask) >> this.blockShift;
var iBlock = (addr & this.busMask) >> this.blockShift;
if (off != this.blockLimit) {
this.aMemBlocks[iBlock].writeWord(off, w & 0xffff);
this.aMemBlocks[iBlock].writeShort(off, w & 0xffff);
return;
}
this.aMemBlocks[iBlock++].writeByte(off, w & 0xff);
@ -649,9 +681,9 @@ Bus.prototype.setShort = function(addr, w)
Bus.prototype.setShortDirect = function(addr, w)
{
var off = addr & this.blockLimit;
var iBlock = (addr & this.addrMask) >> this.blockShift;
var iBlock = (addr & this.busMask) >> this.blockShift;
if (off != this.blockLimit) {
this.aMemBlocks[iBlock].writeWordDirect(off, w & 0xffff);
this.aMemBlocks[iBlock].writeShortDirect(off, w & 0xffff);
return;
}
this.aMemBlocks[iBlock++].writeByteDirect(off, w & 0xff);
@ -672,7 +704,7 @@ Bus.prototype.setShortDirect = function(addr, w)
Bus.prototype.setLong = function(addr, l)
{
var off = addr & this.blockLimit;
var iBlock = (addr & this.addrMask) >> this.blockShift;
var iBlock = (addr & this.busMask) >> this.blockShift;
if (off < this.blockLimit - 2) {
this.aMemBlocks[iBlock].writeLong(off, l);
return;
@ -699,7 +731,7 @@ Bus.prototype.setLong = function(addr, l)
Bus.prototype.setLongDirect = function(addr, l)
{
var off = addr & this.blockLimit;
var iBlock = (addr & this.addrMask) >> this.blockShift;
var iBlock = (addr & this.busMask) >> this.blockShift;
if (off < this.blockLimit - 2) {
this.aMemBlocks[iBlock].writeLongDirect(off, l);
return;
@ -819,7 +851,7 @@ Bus.prototype.writeBackTrackObject = function(addr, bto, off)
Bus.prototype.readBackTrack = function(addr)
{
if (BACKTRACK) {
return this.aMemBlocks[(addr & this.addrMask) >> this.blockShift].readBackTrack(addr & this.blockLimit);
return this.aMemBlocks[(addr & this.busMask) >> this.blockShift].readBackTrack(addr & this.blockLimit);
}
return 0;
};
@ -835,9 +867,11 @@ Bus.prototype.writeBackTrack = function(addr, bti)
{
if (BACKTRACK) {
var slot = bti >>> Bus.BACKTRACK.SLOT_SHIFT;
var btiPrev = this.aMemBlocks[(addr & this.addrMask) >> this.blockShift].writeBackTrack(addr & this.blockLimit, bti);
var iBlock = (addr & this.busMask) >> this.blockShift;
var btiPrev = this.aMemBlocks[iBlock].writeBackTrack(addr & this.blockLimit, bti);
var slotPrev = btiPrev >>> Bus.BACKTRACK.SLOT_SHIFT;
if (slot != slotPrev) {
this.aMemBlocks[iBlock].modBackTrack(true);
if (btiPrev && slotPrev) {
var btoPrev = this.abtObjects[slotPrev-1];
if (!btoPrev) {
@ -935,7 +969,7 @@ Bus.prototype.updateBackTrackCode = function(addr, bti)
} else {
return;
}
this.aMemBlocks[(addr & this.addrMask) >> this.blockShift].writeBackTrack(addr & this.blockLimit, bti);
this.aMemBlocks[(addr & this.busMask) >> this.blockShift].writeBackTrack(addr & this.blockLimit, bti);
}
};