--- /dev/null
+# Copyright (c) 2004 The Regents of The University of Michigan
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Ali Saidi
+
+obj-m := devtime.o
--- /dev/null
+/*
+ * Copyright (c) 2004 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/module.h>
+#include <linux/config.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <asm/uaccess.h>
+#include <linux/kernel.h>
+#include <asm/io.h>
+#include <linux/netdevice.h>
+
+#ifdef __i386__
+#include <asm/processor.h>
+#include <asm/msr.h>
+#endif
+
+#define DRIVER_AUTHOR "Ali Saidi"
+#define DRIVER_DESC "Interface to time uncacachable read and writes to device registers"
+#define DRIVER_VER "0.1"
+
+static unsigned long devCnt, devSum, devSsq;
+static char *dataAddr = NULL;
+static int count = 0;
+
+static inline uint32_t cycleCounter(uint32_t dep);
+
+static int __init devtime_start(void)
+{
+ uint64_t addr;
+ uint32_t t1, t2;
+ uint32_t trash;
+ int x;
+
+ struct net_device *dev;
+
+
+ printk("Devtime Driver Version %s Loaded...\n", DRIVER_VER);
+
+ if ((dataAddr != 0) && (count != 0))
+ {
+ addr = simple_strtoull(dataAddr, NULL, 0);
+
+ devSum = 0;
+ devCnt = count;
+
+ printk("Preparing to read %#llx %d times.\n", addr, count);
+
+ t1 = cycleCounter(trash);
+ for (x=0; x < count; x++)
+ {
+ trash = readl(addr);
+ t2 = cycleCounter(trash);
+ devSum += t2 - t1;
+ t1 = t2;
+ }
+
+ printk("Read Address %#llx %ld times. Average latency %ld.\n", addr, devCnt, devSum/devCnt);
+ } else {
+ dev = dev_get_by_name("eth0");
+ if (dev)
+ {
+ printk("Eth0: MemStart: %#lx MemEnd: %#lx I/O Addr: %#lx\n", dev->mem_start,
+ dev->mem_end, dev->base_addr);
+ dev_put(dev);
+ }
+ dev = dev_get_by_name("eth1");
+ if (dev)
+ {
+ printk("Eth1: MemStart: %#lx MemEnd: %#lx I/O Addr: %#lx\n", dev->mem_start,
+ dev->mem_end, dev->base_addr);
+ dev_put(dev);
+ }
+
+
+ printk("Required information not supplied.\n");
+ }
+
+ return 0;
+}
+
+#ifdef __i386__
+
+static inline uint32_t cycleCounter(uint32_t dep)
+{
+ uint32_t time;
+ cpuid_eax(0);
+ rdtscl(time);
+ cpuid_eax(0);
+ return time;
+}
+
+#elif __alpha__
+
+inline uint32_t cycleCounter(uint32_t dep)
+{
+ uint32_t res;
+ asm volatile ("rpcc %0, %1" : "=r"(res) : "r" (dep) : "memory");
+ return res;
+}
+#else
+#error Architecture NOT SUPPORTE
+#endif
+
+static void __exit devtime_end(void) {
+ printk("Devtime Driver Version %s Unloaded...\n", DRIVER_VER);
+}
+
+
+module_init(devtime_start);
+module_exit(devtime_end);
+
+MODULE_LICENSE("BSD");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+module_param(dataAddr, charp, 0);
+module_param(count, int, 0);