--- trunk/src/devices/dev_8259.c	2007/10/08 16:18:31	11
+++ trunk/src/devices/dev_8259.c	2007/10/08 16:18:38	12
@@ -25,11 +25,11 @@
  *  SUCH DAMAGE.
  *   
  *
- *  $Id: dev_8259.c,v 1.10 2005/06/20 05:52:48 debug Exp $
+ *  $Id: dev_8259.c,v 1.14 2005/08/05 09:08:20 debug Exp $
  *  
  *  8259 Programmable Interrupt Controller.
  *
- *  This is mostly bogus. TODO. See the following URL for more details:
+ *  See the following URL for more details:
  *	http://www.nondot.org/sabre/os/files/MiscHW/8259pic.txt
  */
 
@@ -48,6 +48,8 @@
 
 #define	DEV_8259_LENGTH		2
 
+/*  #define DEV_8259_DEBUG  */
+
 
 /*
  *  dev_8259_access():
@@ -58,9 +60,18 @@
 {
 	struct pic8259_data *d = (struct pic8259_data *) extra;
 	uint64_t idata = 0, odata = 0;
+	int i;
 
 	idata = memory_readmax64(cpu, data, len);
 
+#ifdef DEV_8259_DEBUG
+	if (writeflag == MEM_READ)
+		fatal("[ 8259: read from 0x%x ]\n", (int)relative_addr);
+	else
+		fatal("[ 8259: write to 0x%x: 0x%x ]\n",
+		    (int)relative_addr, (int)idata);
+#endif
+
 	switch (relative_addr) {
 	case 0x00:
 		if (writeflag == MEM_WRITE) {
@@ -73,9 +84,10 @@
 					fatal("[ 8259: WARNING: Bit 2 set ]\n");
 				/*  Bit 1: 0=cascade, 1=single  */
 				/*  Bit 0: 1=4th init byte  */
-				if (!(idata & 0x01))
+				/*  This happens on non-x86 systems:
+				    if (!(idata & 0x01))
 					fatal("[ 8259: WARNING: Bit 0 NOT set!"
-					    "!! ]\n");
+					    "!! ]\n");  */
 				d->init_state = 1;
 				break;
 			}
@@ -94,12 +106,26 @@
 			case 0x0b:
 				d->current_command = 0x0b;
 				break;
+			case 0x0c:
+				/*  Put Master in Buffered Mode  */
+				d->current_command = 0x0c;
+				break;
 			case 0x20:	/*  End Of Interrupt  */
+				/*
+				 *  TODO: in buffered mode, is this an EOI 0?
+				 */
 				d->irr &= ~d->isr;
 				d->isr = 0;
 				/*  Recalculate interrupt assertions:  */
-				cpu_interrupt(cpu, 16);
+				cpu_interrupt(cpu, d->irq_nr);
 				break;
+			case 0x21:	/*  Specific EOI  */
+			case 0x22:
+			case 0x23:
+			case 0x24:
+			case 0x25:
+			case 0x26:
+			case 0x27:
 			case 0x60:
 			case 0x61:
 			case 0x62:
@@ -111,7 +137,7 @@
 				d->irr &= ~(1 << (idata & 7));
 				d->isr &= ~(1 << (idata & 7));
 				/*  Recalculate interrupt assertions:  */
-				cpu_interrupt(cpu, 16);
+				cpu_interrupt(cpu, d->irq_nr);
 				break;
 			case 0x68:	/*  Set Special Mask Mode  */
 				/*  TODO  */
@@ -139,10 +165,28 @@
 			case 0x0b:
 				odata = d->isr;
 				break;
+			case 0x0c:
+				/*  Buffered mode.  */
 			default:
-				fatal("[ 8259: unimplemented command 0x%02x"
-				    " while reading ]\n", d->current_command);
-				cpu->running = 0;
+				odata = 0x00;
+				for (i=0; i<8; i++)
+					if ((d->irr >> i) & 1) {
+						odata = 0x80 | i;
+						break;
+					}
+				break;
+			/*
+			 *  TODO: The "default" label should really do
+			 *  something like this:
+			 *
+			 *	fatal("[ 8259: unimplemented command 0x%02x"
+			 *	    " while reading ]\n", d->current_command);
+			 *	cpu->running = 0;
+			 *
+			 *  but Linux seems to read from the secondary PIC
+			 *  in a manner which works better the way things
+			 *  are coded right now.
+			 */
 			}
 		}
 		break;
@@ -150,10 +194,11 @@
 		if (d->init_state > 0) {
 			if (d->init_state == 1) {
 				d->irq_base = idata & 0xf8;
-				if (idata & 7)
+				/*  This happens on non-x86 machines:
+				    if (idata & 7)
 					fatal("[ 8259: WARNING! Lowest"
 					    " bits in Init Cmd 1 are"
-					    " non-zero! ]\n");
+					    " non-zero! ]\n");  */
 				d->init_state = 2;
 			} else if (d->init_state == 2) {
 				/*  Slave attachment. TODO  */
@@ -174,7 +219,7 @@
 		if (writeflag == MEM_WRITE) {
 			d->ier = idata;
 			/*  Recalculate interrupt assertions:  */
-			cpu_interrupt(cpu, 16);
+			cpu_interrupt(cpu, d->irq_nr);
 		} else {
 			odata = d->ier;
 		}
@@ -200,12 +245,22 @@
 
 /*
  *  devinit_8259():
+ *
+ *  Initialize an 8259 PIC. Important notes:
+ *
+ *	x)  Most systems use _TWO_ 8259 PICs. These should be registered
+ *	    as separate devices.
+ *
+ *	x)  The irq number specified is the number used to re-calculate
+ *	    CPU interrupt assertions.  It is _not_ the irq number at
+ *	    which the PIC is connected. (That is left to machine specific
+ *	    code in src/machine.c.)
  */
 int devinit_8259(struct devinit *devinit)
 {
 	struct pic8259_data *d = malloc(sizeof(struct pic8259_data));
 	char *name2;
-	int nlen = 40;
+	size_t nlen = strlen(devinit->name) + 20;
 
 	if (d == NULL) {
 		fprintf(stderr, "out of memory\n");
@@ -216,11 +271,13 @@
 
 	name2 = malloc(nlen);
 	snprintf(name2, nlen, "%s", devinit->name);
-	if ((devinit->addr & 0xfff) == 0xa0)
+	if ((devinit->addr & 0xfff) == 0xa0) {
 		strlcat(name2, " [secondary]", nlen);
+		d->irq_base = 8;
+	}
 
 	memory_device_register(devinit->machine->memory, name2,
-	    devinit->addr, DEV_8259_LENGTH, dev_8259_access, (void *)d,
+	    devinit->addr, DEV_8259_LENGTH, dev_8259_access, d,
 	    MEM_DEFAULT, NULL);
 
 	devinit->return_ptr = d;