freebsd-dev/sys/dev/fdt/fdt_clock.c

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/*-
* Copyright (c) 2014 Ian Lepore <ian@freebsd.org>
* 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 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.
*
* $FreeBSD$
*/
#include <sys/cdefs.h>
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/queue.h>
#include <sys/systm.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include "fdt_clock_if.h"
#include <dev/fdt/fdt_clock.h>
/*
* Loop through all the tuples in the clocks= property for a device, enabling or
* disabling each clock.
*
* Be liberal about errors for now: warn about a failure to enable but keep
* trying with any other clocks in the list. Return ENXIO if any errors were
* found, and let the caller decide whether the problem is fatal.
*/
static int
enable_disable_all(device_t consumer, boolean_t enable)
{
phandle_t cnode;
device_t clockdev;
int clocknum, err, i, ncells;
uint32_t *clks;
boolean_t anyerrors;
cnode = ofw_bus_get_node(consumer);
ncells = OF_getencprop_alloc_multi(cnode, "clocks", sizeof(*clks),
(void **)&clks);
if (enable && ncells < 2) {
device_printf(consumer, "Warning: No clocks specified in fdt "
"data; device may not function.");
return (ENXIO);
}
anyerrors = false;
for (i = 0; i < ncells; i += 2) {
clockdev = OF_device_from_xref(clks[i]);
clocknum = clks[i + 1];
if (clockdev == NULL) {
if (enable)
device_printf(consumer, "Warning: can not find "
"driver for clock number %u; device may not "
"function\n", clocknum);
anyerrors = true;
continue;
}
if (enable)
err = FDT_CLOCK_ENABLE(clockdev, clocknum);
else
err = FDT_CLOCK_DISABLE(clockdev, clocknum);
if (err != 0) {
if (enable)
device_printf(consumer, "Warning: failed to "
"enable clock number %u; device may not "
"function\n", clocknum);
anyerrors = true;
}
}
OF_prop_free(clks);
return (anyerrors ? ENXIO : 0);
}
int
fdt_clock_get_info(device_t consumer, int n, struct fdt_clock_info *info)
{
phandle_t cnode;
device_t clockdev;
int clocknum, err, ncells;
uint32_t *clks;
cnode = ofw_bus_get_node(consumer);
ncells = OF_getencprop_alloc_multi(cnode, "clocks", sizeof(*clks),
(void **)&clks);
if (ncells <= 0)
return (ENXIO);
n *= 2;
if (ncells <= n)
err = ENXIO;
else {
clockdev = OF_device_from_xref(clks[n]);
if (clockdev == NULL)
err = ENXIO;
else {
/*
* Make struct contents minimally valid, then call
* provider to fill in what it knows (provider can
* override anything it wants to).
*/
clocknum = clks[n + 1];
bzero(info, sizeof(*info));
info->provider = clockdev;
info->index = clocknum;
info->name = "";
err = FDT_CLOCK_GET_INFO(clockdev, clocknum, info);
}
}
OF_prop_free(clks);
return (err);
}
int
fdt_clock_enable_all(device_t consumer)
{
return (enable_disable_all(consumer, true));
}
int
fdt_clock_disable_all(device_t consumer)
{
return (enable_disable_all(consumer, false));
}
void
fdt_clock_register_provider(device_t provider)
{
OF_device_register_xref(
OF_xref_from_node(ofw_bus_get_node(provider)), provider);
}
void
fdt_clock_unregister_provider(device_t provider)
{
OF_device_register_xref(OF_xref_from_device(provider), NULL);
}