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author | ian <ian@FreeBSD.org> | 2014-10-26 02:19:03 +0000 |
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committer | ian <ian@FreeBSD.org> | 2014-10-26 02:19:03 +0000 |
commit | d41355d9bfa1b106803009c608ab31a54f1f4a80 (patch) | |
tree | db6cc3ee6eb451f28c0f167c37587ce982f07dc3 /sys/dev/fdt/fdt_clock.c | |
parent | 04b1fcec06dbbd14589c82ddeceecd06e367cf70 (diff) | |
download | FreeBSD-src-d41355d9bfa1b106803009c608ab31a54f1f4a80.zip FreeBSD-src-d41355d9bfa1b106803009c608ab31a54f1f4a80.tar.gz |
MFC r270957, r270959:
Create an interface for drivers to enable or disable their clocks as listed
in the clocks=<...> properties of their FDT data.
Diffstat (limited to 'sys/dev/fdt/fdt_clock.c')
-rw-r--r-- | sys/dev/fdt/fdt_clock.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/sys/dev/fdt/fdt_clock.c b/sys/dev/fdt/fdt_clock.c new file mode 100644 index 0000000..e471523 --- /dev/null +++ b/sys/dev/fdt/fdt_clock.c @@ -0,0 +1,161 @@ +/*- + * 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(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; + } + } + free(clks, M_OFWPROP); + 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(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); + } + } + free(clks, M_OFWPROP); + 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_device(provider), provider); +} + +void +fdt_clock_unregister_provider(device_t provider) +{ + + OF_device_register_xref(OF_xref_from_device(provider), NULL); +} + |