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diff --git a/payloads/libpayload/arch/i386/timer.c b/payloads/libpayload/arch/i386/timer.c
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+/*
+ * This file is part of the libpayload project.
+ *
+ * Copyright (C) 2008 Advanced Micro Devices, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ */
+
+/**
+ * @file i386/timer.c
+ * i386 specific timer routines
+ */
+
+#include <libpayload.h>
+#include <arch/rdtsc.h>
+
+/**
+ * @ingroup arch
+ * Global variable containing the speed of the processor in KHz.
+ */
+u32 cpu_khz;
+
+/**
+ * Calculate the speed of the processor for use in delays.
+ *
+ * @return The CPU speed in kHz.
+ */
+unsigned int get_cpu_speed(void)
+{
+ unsigned long long start, end;
+
+ /* Set up the PPC port - disable the speaker, enable the T2 gate. */
+ outb((inb(0x61) & ~0x02) | 0x01, 0x61);
+
+ /* Set the PIT to Mode 0, counter 2, word access. */
+ outb(0xB0, 0x43);
+
+ /* Load the counter with 0xffff. */
+ outb(0xff, 0x42);
+ outb(0xff, 0x42);
+
+ /* Read the number of ticks during the period. */
+ start = rdtsc();
+ while (!(inb(0x61) & 0x20)) ;
+ end = rdtsc();
+
+ /*
+ * The clock rate is 1193180 Hz, the number of milliseconds for a
+ * period of 0xffff is 1193180 / (0xFFFF * 1000) or .0182.
+ * Multiply that by the number of measured clocks to get the kHz value.
+ */
+ cpu_khz = (unsigned int)((end - start) * 1193180U / (1000 * 0xffff));
+
+ return cpu_khz;
+}
+
+static inline void _delay(unsigned long long delta)
+{
+ unsigned long long timeout = rdtsc() + delta;
+ while (rdtsc() < timeout) ;
+}
+
+/**
+ * Delay for a specified number of nanoseconds.
+ *
+ * @param n Number of nanoseconds to delay for.
+ */
+void ndelay(unsigned int n)
+{
+ _delay(n * cpu_khz / 1000000);
+}
+
+/**
+ * Delay for a specified number of microseconds.
+ *
+ * @param n Number of microseconds to delay for.
+ */
+void udelay(unsigned int n)
+{
+ _delay(n * cpu_khz / 1000);
+}
+
+/**
+ * Delay for a specified number of milliseconds.
+ *
+ * @param m Number of milliseconds to delay for.
+ */
+void mdelay(unsigned int m)
+{
+ _delay(m * cpu_khz);
+}
+
+/**
+ * Delay for a specified number of seconds.
+ *
+ * @param s Number of seconds to delay for.
+ */
+void delay(unsigned int s)
+{
+ _delay(s * cpu_khz * 1000);
+}