blob: d46d6f00c9dc9b7335c90c8b77a7028bdef9e68c [file] [log] [blame]
/*
* 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
*/
#include <asm/io.h>
#include <asm/page.h>
#include <asm/uaccess.h>
#include <linux/config.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/netdevice.h>
#ifdef __i386__
#include <asm/msr.h>
#include <asm/processor.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 char *dataAddr = NULL;
static int count = 0;
#ifdef __alpha__
static int memTest = 0;
#endif
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;
uint32_t *times;
uint32_t num = 0;
struct net_device *dev;
printk("Devtime Driver Version %s Loaded...\n", DRIVER_VER);
#ifdef __alpha__
if (memTest) {
addr = 0xfffffc0000000000;
// addr += 16*1024*1024;
printk("Preparing memory test.\n");
t1 = cycleCounter(trash);
for (x = 0; x < count; x++) {
trash = readl(addr);
t2 = cycleCounter(trash);
times[num++] = t2 - t1;
t1 = t2;
addr += 4096;
}
printk("Measurements:\n");
for (x = 0; x < count; x++) {
printk("%d ", times[x]);
if (((x + 1) % 10) == 0)
printk("\n");
}
printk("\nDone.\n");
} else
#endif
if (dataAddr != 0 && count != 0) {
addr = simple_strtoull(dataAddr, NULL, 0);
addr = ioremap(addr, PAGE_SIZE);
/**
* Make sure that the remapping actually worked. On alpha we have
* linear addressing, so its not a problem. But it can fail in x86
* if physical memory is mapped to this address.
*/
times = kmalloc(sizeof(uint32_t) * count, GFP_USER);
if (!times) {
printk("Could not allocate memory... Try again later.\n");
return -1;
}
if (addr) {
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);
times[num++] = t2 - t1;
t1 = t2;
}
/**
* Unmap the address.
*/
iounmap(addr);
printk("Measurements:\n");
for (x = 0; x < count; x++) {
printk("%d ", times[x]);
if (((x + 1) % 10) == 0)
printk("\n");
}
printk("\nDone.\n");
} else {
printk("Unable to remap address. Please try again later.\n");
}
} 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 = 0;
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 SUPPORTED
#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("Dual BSD/GPL");
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
module_param(dataAddr, charp, 0);
module_param(count, int, 0);
#ifdef __alpha__
module_param(memTest, int, 0);
#endif