xnu-2782.20.48.tar.gz

[apple/xnu.git] / iokit / IOKit / IOInterruptEventSource.h

diff --git a/iokit/IOKit/IOInterruptEventSource.h b/iokit/IOKit/IOInterruptEventSource.h
index 0be7caf4575ee0a02c011dbc04ec5fb2136a734f..553eb4104a8e5fbe56bc8371fd7869f7e7a21de3 100644 (file)
--- a/iokit/IOKit/IOInterruptEventSource.h
+++ b/iokit/IOKit/IOInterruptEventSource.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 1998-2014 Apple Computer, Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
@@ -42,6 +42,8 @@ HISTORY
 
 class IOService;
 
+struct IOInterruptAccountingData;
+
 /*! @class IOInterruptEventSource : public IOEventSource
     @abstract Event source for interrupt delivery to work-loop based drivers.
     @discussion The IOInterruptEventSource is a generic object that delivers calls interrupt routines in it's client in a guaranteed single-threaded manner.  IOInterruptEventSource is part of the IOKit $link IOWorkLoop infrastructure where the semantic that one and only one action method is executing within a work-loops event chain.
@@ -96,7 +98,9 @@ protected:
 /*! @struct ExpansionData
     @discussion This structure will be used to expand the capablilties of the IOWorkLoop in the future.
     */    
-    struct ExpansionData { };
+    struct ExpansionData {
+        IOInterruptAccountingData * statistics;
+    };
 
 /*! @var reserved
     Reserved for future use.  (Internal use only)  */
@@ -112,6 +116,10 @@ protected:
     @result Return true if this function needs to be called again before all its outstanding events have been processed. */
     virtual bool checkForWork();
 
+/*! @function setWorkLoop
+    @abstract Sub-class implementation of setWorkLoop method. */
+    virtual void setWorkLoop(IOWorkLoop *inWorkLoop);
+
 public:
 
 /*! @function interruptEventSource
@@ -185,6 +193,21 @@ state when checkForWork is called. */
     @param nub Where did the interrupt originate from
     @param ind What is this interrupts index within 'nub'. */
     virtual void disableInterruptOccurred(void *, IOService *nub, int ind);
+    
+/*! @function warmCPU
+    @abstract Tries to reduce latency for an interrupt which will be received near a specified time.
+    @discussion Warms up a CPU in advance of an interrupt so that the interrupt may be serviced with predictable latency.  
+    The warm-up is not periodic; callers should call warmCPU once in advance of each interrupt.  It is recommended that
+    requests be issues in serial (i.e. each after the target for the previous call has elapsed), as there is a systemwide
+    cap on the number of outstanding requests.  This routine may be disruptive to the system if used with very small intervals
+    between requests; it should be used only in cases where interrupt latency is absolutely critical, and tens or hundreds of 
+    milliseconds between targets is the expected time scale.  NOTE: it is not safe to call this method with interrupts disabled.
+    @param abstime Time at which interrupt is expected. */
+    IOReturn warmCPU(uint64_t abstime);
+
+private:
+    IOReturn registerInterruptHandler(IOService *inProvider, int inIntIndex);
+    void unregisterInterruptHandler(IOService *inProvider, int inIntIndex);
 
 private:
     OSMetaClassDeclareReservedUnused(IOInterruptEventSource, 0);