Detect Geode CPUs and initialize the 27MHz timecounter "Geode".

This timecounter is 2usec faster than the i8254 and has 22 times
better resolution.

1 files changed, 100 insertions, 0 deletions

diff --git a/sys/i386/i386/geode.c b/sys/i386/i386/geode.c
new file mode 100644
index 000000000000..4beaed3b544c
--- /dev/null
+++ b/sys/i386/i386/geode.c
@@ -0,0 +1,100 @@
+/*-
+ * Copyright (c) 2003 Poul-Henning Kamp
+ * All rights reserved.
+ *
+ * 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 names of the authors 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/timetc.h>
+#include <sys/bus.h>
+#include <sys/kernel.h>
+#include <dev/pci/pcivar.h>
+
+static unsigned	cba;
+static unsigned	geode_counter;
+
+static unsigned
+geode_get_timecount(struct timecounter *tc)
+{
+	return (inl(geode_counter));
+}
+
+static struct timecounter geode_timecounter = {
+	geode_get_timecount,
+	NULL,
+	0xffffffff,
+	27000000,
+	"Geode",
+	1000
+};
+
+
+static int
+geode_probe(device_t self)
+{
+
+	if (pci_get_devid(self) != 0x0515100b)
+		return (ENXIO);
+	if (geode_counter != 0)
+		return (ENXIO);
+	cba = pci_read_config(self, 0x64, 4);
+	printf("Geode CBA@ 0x%x\n", cba);
+	geode_counter = cba + 0x08;
+	outl(cba + 0x0d, 2);
+	tc_init(&geode_timecounter);
+	return (ENXIO);
+}
+
+static int
+geode_attach(device_t self)
+{
+
+	return(ENODEV);
+}
+
+static device_method_t geode_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		geode_probe),
+	DEVMETHOD(device_attach,	geode_attach),
+	DEVMETHOD(device_suspend,	bus_generic_suspend),
+	DEVMETHOD(device_resume,	bus_generic_resume),
+	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
+	{0, 0}
+};
+ 
+static driver_t geode_driver = {
+	"geode",
+	geode_methods,
+	0,
+};
+
+static devclass_t geode_devclass;
+
+DRIVER_MODULE(geode, pci, geode_driver, geode_devclass, 0, 0);