This change adds PPC support to libpayload, and hooks it up in the build

process.
The PPC support is still stubbed, with commented out x86 code as guide
line for an implementor.

Signed-off-by: Patrick Georgi <patrick.georgi@coresystems.de>
Acked-by: Stefan Reinauer <stepan@coresystems.de>


git-svn-id: svn://svn.coreboot.org/coreboot/trunk@4293 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

1 files changed, 122 insertions, 0 deletions

diff --git a/payloads/libpayload/arch/i386/timer.c b/payloads/libpayload/arch/i386/timer.c
new file mode 100644
index 0000000000..3d8607b3cb
--- /dev/null
+++ b/payloads/libpayload/arch/i386/timer.c
@@ -0,0 +1,122 @@
+/*
+ * 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);
+}