freebsd-skq/sys/powerpc/powermac/vcoregpio.c
pfg 6f8905baf6 sys/powerpc: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-27 15:09:59 +00:00

115 lines
3.2 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2009 Nathan Whitehorn
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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/module.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/cpu.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/openfirm.h>
#include <powerpc/powermac/macgpiovar.h>
static int vcoregpio_probe(device_t);
static int vcoregpio_attach(device_t);
static void vcoregpio_pre_change(device_t, const struct cf_level *level);
static void vcoregpio_post_change(device_t, const struct cf_level *level);
static device_method_t vcoregpio_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, vcoregpio_probe),
DEVMETHOD(device_attach, vcoregpio_attach),
{ 0, 0 },
};
static driver_t vcoregpio_driver = {
"vcoregpio",
vcoregpio_methods,
0
};
static devclass_t vcoregpio_devclass;
DRIVER_MODULE(vcoregpio, macgpio, vcoregpio_driver, vcoregpio_devclass, 0, 0);
static int
vcoregpio_probe(device_t dev)
{
const char *name = ofw_bus_get_name(dev);
if (strcmp(name, "cpu-vcore-select") != 0)
return (ENXIO);
device_set_desc(dev, "CPU Core Voltage Control");
return (0);
}
static int
vcoregpio_attach(device_t dev)
{
EVENTHANDLER_REGISTER(cpufreq_pre_change, vcoregpio_pre_change, dev,
EVENTHANDLER_PRI_ANY);
EVENTHANDLER_REGISTER(cpufreq_post_change, vcoregpio_post_change, dev,
EVENTHANDLER_PRI_ANY);
return (0);
}
static void
vcoregpio_pre_change(device_t dev, const struct cf_level *level)
{
if (level->rel_set[0].freq == 10000 /* max */) {
/*
* Make sure the CPU voltage is raised before we raise
* the clock.
*/
macgpio_write(dev, GPIO_DDR_OUTPUT | 1);
DELAY(1000);
}
}
static void
vcoregpio_post_change(device_t dev, const struct cf_level *level)
{
if (level->rel_set[0].freq < 10000 /* max */) {
DELAY(1000);
/* We are safe to reduce CPU voltage now */
macgpio_write(dev, GPIO_DDR_OUTPUT | 0);
}
}