patch-2.4.19 linux-2.4.19/arch/ppc64/kernel/ItLpQueue.c

• Lines: 171
• Date: Fri Aug 2 17:39:43 2002
• Orig file: linux-2.4.18/arch/ppc64/kernel/ItLpQueue.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.18/arch/ppc64/kernel/ItLpQueue.c linux-2.4.19/arch/ppc64/kernel/ItLpQueue.c
@@ -0,0 +1,170 @@
+/*
+ * ItLpQueue.c
+ * Copyright (C) 2001 Mike Corrigan  IBM Corporation
+ * 
+ * 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.
+ */
+
+#include <linux/stddef.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <asm/system.h>
+#include <asm/paca.h>
+#include <asm/iSeries/ItLpQueue.h>
+#include <asm/iSeries/HvLpEvent.h>
+#include <asm/iSeries/HvCallEvent.h>
+#include <asm/iSeries/LparData.h>
+
+static __inline__ int set_inUse( struct ItLpQueue * lpQueue )
+{
+	int t;
+	u32 * inUseP = &(lpQueue->xInUseWord);
+
+	__asm__ __volatile__("\n\
+1:	lwarx	%0,0,%2		\n\
+	cmpi	0,%0,0		\n\
+	li	%0,0		\n\
+	bne-	2f		\n\
+	addi	%0,%0,1		\n\
+	stwcx.	%0,0,%2		\n\
+	bne-	1b		\n\
+2:	eieio"
+	: "=&r" (t), "=m" (lpQueue->xInUseWord)
+	: "r" (inUseP), "m" (lpQueue->xInUseWord)
+	: "cc");
+
+	return t;
+}
+
+static __inline__ void clear_inUse( struct ItLpQueue * lpQueue )
+{
+	lpQueue->xInUseWord = 0;
+}
+
+/* Array of LpEvent handler functions */
+extern LpEventHandler lpEventHandler[HvLpEvent_Type_NumTypes];
+unsigned long ItLpQueueInProcess = 0;
+
+struct HvLpEvent * ItLpQueue_getNextLpEvent( struct ItLpQueue * lpQueue )
+{
+	struct HvLpEvent * nextLpEvent = 
+		(struct HvLpEvent *)lpQueue->xSlicCurEventPtr;
+	if ( nextLpEvent->xFlags.xValid ) {
+		/* rmb() needed only for weakly consistent machines (regatta) */
+		rmb();
+		/* Set pointer to next potential event */
+		lpQueue->xSlicCurEventPtr += ((nextLpEvent->xSizeMinus1 +
+				      LpEventAlign ) /
+				      LpEventAlign ) *
+				      LpEventAlign;
+		/* Wrap to beginning if no room at end */
+		if (lpQueue->xSlicCurEventPtr > lpQueue->xSlicLastValidEventPtr)
+			lpQueue->xSlicCurEventPtr = lpQueue->xSlicEventStackPtr;
+	}
+	else 
+		nextLpEvent = NULL;
+
+	return nextLpEvent;
+}
+
+int ItLpQueue_isLpIntPending( struct ItLpQueue * lpQueue )
+{
+	int retval = 0;
+	struct HvLpEvent * nextLpEvent;
+	if ( lpQueue ) {
+		nextLpEvent = (struct HvLpEvent *)lpQueue->xSlicCurEventPtr;
+		retval = nextLpEvent->xFlags.xValid | lpQueue->xPlicOverflowIntPending;
+	}
+	return retval;
+}
+
+void ItLpQueue_clearValid( struct HvLpEvent * event )
+{
+	/* Clear the valid bit of the event
+	 * Also clear bits within this event that might
+	 * look like valid bits (on 64-byte boundaries)
+   	 */
+	unsigned extra = (( event->xSizeMinus1 + LpEventAlign ) /
+						 LpEventAlign ) - 1;
+	switch ( extra ) {
+	  case 3:
+	   ((struct HvLpEvent*)((char*)event+3*LpEventAlign))->xFlags.xValid=0;
+	  case 2:
+	   ((struct HvLpEvent*)((char*)event+2*LpEventAlign))->xFlags.xValid=0;
+	  case 1:
+	   ((struct HvLpEvent*)((char*)event+1*LpEventAlign))->xFlags.xValid=0;
+	  case 0:
+	   ;	
+	}
+	mb();
+	event->xFlags.xValid = 0;
+}
+
+unsigned ItLpQueue_process( struct ItLpQueue * lpQueue, struct pt_regs *regs )
+{
+	unsigned numIntsProcessed = 0;
+	struct HvLpEvent * nextLpEvent;
+
+	/* If we have recursed, just return */
+	if ( !set_inUse( lpQueue ) )
+		return 0;
+	
+	if (ItLpQueueInProcess == 0)
+		ItLpQueueInProcess = 1;
+	else
+		BUG();
+
+	for (;;) {
+		nextLpEvent = ItLpQueue_getNextLpEvent( lpQueue );
+		if ( nextLpEvent ) {
+			/* Count events to return to caller
+			 * and count processed events in lpQueue
+ 			 */
+			++numIntsProcessed;
+			lpQueue->xLpIntCount++;		
+			/* Call appropriate handler here, passing 
+			 * a pointer to the LpEvent.  The handler
+			 * must make a copy of the LpEvent if it
+			 * needs it in a bottom half. (perhaps for
+			 * an ACK)
+			 *	
+			 *  Handlers are responsible for ACK processing 
+			 *
+			 * The Hypervisor guarantees that LpEvents will
+			 * only be delivered with types that we have
+			 * registered for, so no type check is necessary
+			 * here!
+  			 */
+			if ( nextLpEvent->xType < HvLpEvent_Type_NumTypes )
+				lpQueue->xLpIntCountByType[nextLpEvent->xType]++;
+			if ( nextLpEvent->xType < HvLpEvent_Type_NumTypes &&
+			     lpEventHandler[nextLpEvent->xType] ) 
+				lpEventHandler[nextLpEvent->xType](nextLpEvent, regs);
+			else
+				printk(KERN_INFO "Unexpected Lp Event type=%d\n", nextLpEvent->xType );
+			
+			ItLpQueue_clearValid( nextLpEvent );
+		}
+		else 	/* No more valid events
+			 * If overflow events are pending
+			 * process them
+			 */
+			if ( lpQueue->xPlicOverflowIntPending ) {
+				HvCallEvent_getOverflowLpEvents( 
+						lpQueue->xIndex);
+			}
+			else	/* If nothing left then we are done */
+				break;
+	}
+
+	ItLpQueueInProcess = 0;
+	mb();
+	clear_inUse( lpQueue );
+
+	get_paca()->lpEvent_count += numIntsProcessed;
+
+	return numIntsProcessed;
+}