baseport/src/cedar/generic/base/syborg/specific/highrestimer.h
changeset 0 ffa851df0825
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/baseport/src/cedar/generic/base/syborg/specific/highrestimer.h	Fri Jul 31 14:43:15 2009 +0100
@@ -0,0 +1,70 @@
+/*
+* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of the License "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:
+*
+*/
+
+/**
+ * @file
+ * @internalTechnology
+ *
+ * The highrestimer.h header file defines how to access the high resoltion
+ * timer, if one is supported.  This file is used by default if the variant does
+ * not export one to \epoc32\include\nkern. 
+ */
+
+#ifndef __HIGHRESTIMER_H__
+#define __HIGHRESTIMER_H__
+//
+// Copyright (c) 2008 Symbian Ltd. All rights reserved.
+//
+
+#include <syborg.h>
+
+/**
+ * Macro indicating that a high resolution timer is supported.
+ */
+#define HAS_HIGH_RES_TIMER
+
+/**
+ * Assembler macro to get the the current value of the high res timer and place
+ * it in the specified register.
+ * Reads the 32-bit value from a free-running counter that represents the current time. 
+ * Syborg timers have 'microsecond resolution'. NB. This value comes from the host clock
+ * and so there is a good chance that the kernels tick based notion of time (elapsed) and that
+ * measured by the free running timer will get out of kilter. This affects t_cputime from e32test
+ * amongst other things.
+ */
+//#define GET_HIGH_RES_TICK_COUNT(Rd) asm("nop");
+// Hi-jacking r10 for tmp, not good if Rd is R10 -- grepping the the kernel shows it's not (for now)
+#define GET_HIGH_RES_TICK_COUNT(Rd)						         \
+  asm("push {r10}");										     \
+  asm("mov r10, #2");										     \
+  asm("ldr "#Rd", =%a0"               : : "i" (KHwBaseRtc + 4)); \
+  asm("str r10, ["#Rd", #%a0]"        : : "i" (0));			     \
+  asm("pop {r10}");                                              \
+  asm("ldr "#Rd", =%a0"               : : "i" (KHwBaseRtc + 8)); \
+  asm("ldr "#Rd", ["#Rd", #%a0]"      : : "i" (0));              
+
+/**
+ * The frequency of the timer in Hz.
+ */
+const TInt KHighResTimerFrequency = 1000000;
+
+/**
+ * Macro indicating that the timer counts up if defined.
+ */
+#define HIGH_RES_TIMER_COUNTS_UP
+
+#endif  // __HIGHRESTIMER_H__