Differential D31311 Diff 92756 sys/dev/fdt/simplepmbus.c

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sys/dev/fdt/simplepmbus.c

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				/*-
				* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
				*
				* Copyright (c) 2021 Oskar Holmlund <oskar.holmlund@ohdata.se>
				*
				* 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.
				*
				*/
				/*
				* Bindings
				* sys/contrib/device-tree/Bindings/bus/simple-pm-bus.yaml
				*/

				#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/kernel.h>
				#include <sys/rman.h>

				#include <dev/extres/clk/clk.h>

				#include <dev/ofw/openfirm.h>
				#include <dev/ofw/ofw_bus.h>
				#include <dev/ofw/ofw_bus_subr.h>

				#include <dev/fdt/simplebus.h>


				struct simple_pm_bus_softc {
				struct simplebus_softc simplebus;
				device_t dev;
				clk_t clk_fck;
				};

				static int
				simple_pm_bus_probe(device_t dev)
				{
				if (!ofw_bus_status_okay(dev))
				return (ENXIO);

				/*
				* for now: require "ranges"
				* later require "clock" or "power-domains" aswell.
				*/
				if (!(ofw_bus_is_compatible(dev, "simple-pm-bus") &&
				ofw_bus_has_prop(dev, "ranges")))
				{
				return (ENXIO);
				}

				device_set_desc(dev, "Simple Power-Managed Bus");

				return (BUS_PROBE_GENERIC);
				}

				static void
				simple_pm_bus_delayed_attach(void *xsc)
				{
				int err;
				struct simple_pm_bus_softc *sc;

				sc = (struct simple_pm_bus_softc *)xsc;

				/* Enable the clock */
				err = clk_enable(sc->clk_fck);
				if (err != 0)
				device_printf(sc->dev, "Failed to enable clk\n");
				}

				static int
				simple_pm_bus_attach(device_t dev)
				{
				struct simple_pm_bus_softc *sc;
				sc = device_get_softc(dev);
				sc->dev = dev;

				if (ofw_bus_has_prop(dev, "power-domains"))
				device_printf(dev,
				"Note power-domains are currently unsupported\n");

				if (ofw_bus_has_prop(dev, "clock")) {
				/* expect one clock */
				manuUnsubmitted Not Done Inline Actions Doesn't seems to be true, I think we can have multiple clocks. manu: Doesn't seems to be true, I think we can have multiple clocks.
				int err;
				err = clk_get_by_ofw_index(dev, 0, 0, &sc->clk_fck);
				if (err != 0) {
				device_printf(dev, "Cant find clock (err %d)\n",
				err);
				return (ENXIO);
				}
				config_intrhook_oneshot(simple_pm_bus_delayed_attach, sc);
				manuUnsubmitted Not Done Inline Actions I've missed that the first time, any reason we don't enable the clock directly ? manu: I've missed that the first time, any reason we don't enable the clock directly ?
				}

				return (simplebus_attach(dev));
				}

				static int
				simple_pm_bus_detach(device_t dev)
				{
				return (simplebus_detach(dev));
				}

				static device_method_t simple_pm_bus_methods[] = {
				DEVMETHOD(device_probe, simple_pm_bus_probe),
				DEVMETHOD(device_attach, simple_pm_bus_attach),
				DEVMETHOD(device_detach, simple_pm_bus_detach),
				DEVMETHOD_END
				};

				DEFINE_CLASS_1(simple_pm_bus, simple_pm_bus_driver, simple_pm_bus_methods,
				sizeof(struct simple_pm_bus_softc), simplebus_driver);

				static devclass_t simple_pm_bus_devclass;
				EARLY_DRIVER_MODULE(simple_pm_bus, simplebus, simple_pm_bus_driver,
				simple_pm_bus_devclass, 0, 0,
				BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);

				MODULE_VERSION(simple_pm_bus, 1);