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X86: Make auto eoi mode work in the I8259 PIC.

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This commit is contained in:
Gabe Black 2008-10-12 23:27:08 -07:00
parent fb5bb434a9
commit be6055e0f2
2 changed files with 15 additions and 3 deletions
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15
src/dev/x86/i8259.cc
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@ -36,7 +36,7 @@ X86ISA::I8259::I8259(Params * p) : BasicPioDevice(p), IntDev(this),
latency(p->pio_latency), output(p->output),
mode(p->mode), slave(NULL),
IRR(0), ISR(0), IMR(0),
readIRR(true), initControlWord(0)
readIRR(true), initControlWord(0), autoEOI(false)
{
if (output) {
I8259 * master;
@ -91,6 +91,9 @@ X86ISA::I8259::write(PacketPtr pkt)
DPRINTF(I8259, "%s mode.\n",
cascadeMode ? "Cascade" : "Single");
expectICW4 = bits(val, 0);
if (!expectICW4) {
autoEOI = false;
}
initControlWord = 1;
DPRINTF(I8259, "Expecting %d more bytes.\n", expectICW4 ? 3 : 2);
} else if (bits(val, 4, 3) == 0) {
@ -203,8 +206,10 @@ X86ISA::I8259::write(PacketPtr pkt)
} else {
DPRINTF(I8259, "Unrecognized buffer mode.\n");
}
autoEOI = bits(val, 1);
DPRINTF(I8259, "%s End Of Interrupt.\n",
bits(val, 1) ? "Automatic" : "Normal");
autoEOI ? "Automatic" : "Normal");
DPRINTF(I8259, "%s mode.\n", bits(val, 0) ? "80x86" : "MCX-80/85");
initControlWord = 0;
break;
@ -265,7 +270,11 @@ X86ISA::I8259::getVector()
int line = findMsbSet(IRR);
IRR &= ~(1 << line);
DPRINTF(I8259, "Interrupt %d was accepted.\n", line);
ISR |= 1 << line;
if (autoEOI) {
handleEOI(line);
} else {
ISR |= 1 << line;
}
if (slave && bits(cascadeBits, line)) {
DPRINTF(I8259, "Interrupt was from slave who will "
"provide the vector.\n");

3
src/dev/x86/i8259.hh
View file

@ -73,6 +73,9 @@ class I8259 : public BasicPioDevice, public IntDev
bool expectICW4;
int initControlWord;
// Whether or not the PIC is in auto EOI mode.
bool autoEOI;
void requestInterrupt(int line);
void handleEOI(int line);