/*- * SPDX-License-Identifier: BSD-2-Clause * * 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 #include #include #include #include #include #include #include #include #include #include #include #include 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); } }