freebsd-dev/sys/dev/ofw/ofw_graph.c
Emmanuel Vadot 9a4eed0be2 ofw_graph: Add functions for graph bindings
Those functions are helpers to work on graph bindings.
graphs are mostly use with video related devices.
See https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/graph.txt?id=4436a3711e3249840e0679e92d3c951bcaf25515

MFC after:	1 month
Differential Revision:	https://reviews.freebsd.org/D19877
2019-04-17 20:09:01 +00:00

187 lines
4.7 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2019 Emmanuel Vadot <manu@FreeBSD.org>
*
* 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,
* without modification, immediately at the beginning of the file.
* 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>
__FBSDID("$FreeBSD$");
#include "opt_platform.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/errno.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <dev/ofw/ofw_graph.h>
#include <dev/ofw/openfirm.h>
#include "ofw_bus_if.h"
#define PORT_MAX_NAME 8
phandle_t
ofw_graph_get_port_by_idx(phandle_t node, uint32_t idx)
{
phandle_t ports, child;
uint32_t reg;
char portnode[PORT_MAX_NAME];
/* First try to find a port@<idx> node */
snprintf(portnode, sizeof(portnode), "port@%d", idx);
child = ofw_bus_find_child(node, portnode);
if (child != 0)
return (child);
/* Next try to look under ports */
ports = ofw_bus_find_child(node, "ports");
if (ports == 0)
return (0);
for (child = OF_child(ports); child != 0; child = OF_peer(child)) {
if (OF_getencprop(child, "reg", &reg, sizeof(uint32_t)) <= 0 ||
reg != idx)
continue;
return (child);
}
return (0);
}
size_t
ofw_graph_port_get_num_endpoints(phandle_t port)
{
phandle_t child;
char *name;
size_t num = 0;
int ret;
for (num = 0, child = OF_child(port); child != 0;
child = OF_peer(child)) {
ret = OF_getprop_alloc(child, "name", (void **)&name);
if (ret == -1)
continue;
if (strcmp(name, "endpoint") == 0)
num++;
else if (strncmp(name, "endpoint@", 9) == 0)
num++;
free(name, M_OFWPROP);
}
return (num);
}
phandle_t
ofw_graph_get_endpoint_by_idx(phandle_t port, uint32_t idx)
{
phandle_t endpoint, child;
uint32_t reg;
/* First test if we have only one endpoint */
endpoint = ofw_bus_find_child(port, "endpoint");
if (endpoint != 0)
return (endpoint);
/* Then test all childs based on the reg property */
for (child = OF_child(port); child != 0; child = OF_peer(child)) {
if (OF_getencprop(child, "reg", &reg, sizeof(uint32_t)) <= 0 ||
reg != idx)
continue;
return (child);
}
return (0);
}
phandle_t
ofw_graph_get_remote_endpoint(phandle_t endpoint)
{
phandle_t remote;
if (OF_getencprop(endpoint, "remote-endpoint", &remote,
sizeof(phandle_t)) <= 0)
return (0);
return (remote);
}
phandle_t
ofw_graph_get_remote_parent(phandle_t remote)
{
phandle_t node;
char *name;
int ret;
/* get the endpoint node */
node = OF_node_from_xref(remote);
/* go to the port@X node */
node = OF_parent(node);
/* go to the ports node or parent */
node = OF_parent(node);
/* if the node name is 'ports' we need to go up one last time */
ret = OF_getprop_alloc(node, "name", (void **)&name);
if (ret == -1) {
printf("%s: Node %x don't have a name, abort\n", __func__, node);
node = 0;
goto end;
}
if (strcmp("ports", name) == 0)
node = OF_parent(node);
end:
free(name, M_OFWPROP);
return (node);
}
device_t
ofw_graph_get_device_by_port_ep(phandle_t node, uint32_t port_id, uint32_t ep_id)
{
phandle_t outport, port, endpoint, remote;
port = ofw_graph_get_port_by_idx(node, port_id);
if (port == 0)
return (NULL);
endpoint = ofw_graph_get_endpoint_by_idx(port, ep_id);
if (endpoint == 0)
return NULL;
remote = ofw_graph_get_remote_endpoint(endpoint);
if (remote == 0)
return (NULL);
outport = ofw_graph_get_remote_parent(remote);
if (outport == 0)
return (NULL);
return (OF_device_from_xref(OF_xref_from_node(outport)));
}