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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/ppc64/kernel/ItLpQueue.c
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/ppc64/kernel/ItLpQueue.c')
-rw-r--r--arch/ppc64/kernel/ItLpQueue.c167
1 files changed, 167 insertions, 0 deletions
diff --git a/arch/ppc64/kernel/ItLpQueue.c b/arch/ppc64/kernel/ItLpQueue.c
new file mode 100644
index 00000000000..c923a815760
--- /dev/null
+++ b/arch/ppc64/kernel/ItLpQueue.c
@@ -0,0 +1,167 @@
+/*
+ * 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\
+ cmpwi 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 if ( lpQueue->xPlicOverflowIntPending )
+ /*
+ * No more valid events. If overflow events are
+ * pending process them
+ */
+ HvCallEvent_getOverflowLpEvents( lpQueue->xIndex);
+ else
+ break;
+ }
+
+ ItLpQueueInProcess = 0;
+ mb();
+ clear_inUse( lpQueue );
+
+ get_paca()->lpevent_count += numIntsProcessed;
+
+ return numIntsProcessed;
+}