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Diffstat (limited to 'payloads/libpayload/arch/powerpc/timer.c')
-rw-r--r-- | payloads/libpayload/arch/powerpc/timer.c | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/payloads/libpayload/arch/powerpc/timer.c b/payloads/libpayload/arch/powerpc/timer.c new file mode 100644 index 0000000000..ba824b0d57 --- /dev/null +++ b/payloads/libpayload/arch/powerpc/timer.c @@ -0,0 +1,127 @@ +/* + * 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) +{ +#if 0 + 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)); +#else + cpu_khz = 200 * 1024; +#endif + return cpu_khz; +} + +static inline void _delay(unsigned long long delta) +{ +#if 0 + unsigned long long timeout = rdtsc() + delta; + while (rdtsc() < timeout) ; +#endif +} + +/** + * 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); +} |