diff options
Diffstat (limited to 'arch/ppc64/kernel/ItLpQueue.c')
| -rw-r--r-- | arch/ppc64/kernel/ItLpQueue.c | 167 |
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 000000000000..c923a815760e --- /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; +} |