1/* Copyright (c) 2012, The Linux Foundation. All rights reserved.
  2 *
  3 * This program is free software; you can redistribute it and/or modify
  4 * it under the terms of the GNU General Public License version 2 and
  5 * only version 2 as published by the Free Software Foundation.
  6 *
  7 * This program is distributed in the hope that it will be useful,
  8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 10 * GNU General Public License for more details.
 11 */
 12
 13#include <linux/types.h>
 14#include <linux/err.h>
 15#include <linux/slab.h>
 16#include <linux/clk.h>
 17#include <linux/of.h>
 18#include <linux/of_address.h>
 19#include <linux/of_graph.h>
 20#include <linux/of_platform.h>
 21#include <linux/platform_device.h>
 22#include <linux/amba/bus.h>
 23#include <linux/coresight.h>
 24#include <linux/cpumask.h>
 25#include <asm/smp_plat.h>
 26
 27
 28static int of_dev_node_match(struct device *dev, void *data)
 29{
 30	return dev->of_node == data;
 31}
 32
 33static struct device *
 34of_coresight_get_endpoint_device(struct device_node *endpoint)
 35{
 36	struct device *dev = NULL;
 37
 38	/*
 39	 * If we have a non-configurable replicator, it will be found on the
 40	 * platform bus.
 41	 */
 42	dev = bus_find_device(&platform_bus_type, NULL,
 43			      endpoint, of_dev_node_match);
 44	if (dev)
 45		return dev;
 46
 47	/*
 48	 * We have a configurable component - circle through the AMBA bus
 49	 * looking for the device that matches the endpoint node.
 50	 */
 51	return bus_find_device(&amba_bustype, NULL,
 52			       endpoint, of_dev_node_match);
 53}
 54
 55static void of_coresight_get_ports(struct device_node *node,
 56				   int *nr_inport, int *nr_outport)
 57{
 58	struct device_node *ep = NULL;
 59	int in = 0, out = 0;
 60
 61	do {
 62		ep = of_graph_get_next_endpoint(node, ep);
 63		if (!ep)
 64			break;
 65
 66		if (of_property_read_bool(ep, "slave-mode"))
 67			in++;
 68		else
 69			out++;
 70
 71	} while (ep);
 72
 73	*nr_inport = in;
 74	*nr_outport = out;
 75}
 76
 77static int of_coresight_alloc_memory(struct device *dev,
 78			struct coresight_platform_data *pdata)
 79{
 80	/* List of output port on this component */
 81	pdata->outports = devm_kzalloc(dev, pdata->nr_outport *
 82				       sizeof(*pdata->outports),
 83				       GFP_KERNEL);
 84	if (!pdata->outports)
 85		return -ENOMEM;
 86
 87	/* Children connected to this component via @outports */
 88	pdata->child_names = devm_kzalloc(dev, pdata->nr_outport *
 89					  sizeof(*pdata->child_names),
 90					  GFP_KERNEL);
 91	if (!pdata->child_names)
 92		return -ENOMEM;
 93
 94	/* Port number on the child this component is connected to */
 95	pdata->child_ports = devm_kzalloc(dev, pdata->nr_outport *
 96					  sizeof(*pdata->child_ports),
 97					  GFP_KERNEL);
 98	if (!pdata->child_ports)
 99		return -ENOMEM;
100
101	return 0;
102}
103
104struct coresight_platform_data *of_get_coresight_platform_data(
105				struct device *dev, struct device_node *node)
106{
107	int i = 0, ret = 0, cpu;
108	struct coresight_platform_data *pdata;
109	struct of_endpoint endpoint, rendpoint;
110	struct device *rdev;
111	struct device_node *dn;
112	struct device_node *ep = NULL;
113	struct device_node *rparent = NULL;
114	struct device_node *rport = NULL;
115
116	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
117	if (!pdata)
118		return ERR_PTR(-ENOMEM);
119
120	/* Use device name as sysfs handle */
121	pdata->name = dev_name(dev);
122
123	/* Get the number of input and output port for this component */
124	of_coresight_get_ports(node, &pdata->nr_inport, &pdata->nr_outport);
125
126	if (pdata->nr_outport) {
127		ret = of_coresight_alloc_memory(dev, pdata);
128		if (ret)
129			return ERR_PTR(ret);
130
131		/* Iterate through each port to discover topology */
132		do {
133			/* Get a handle on a port */
134			ep = of_graph_get_next_endpoint(node, ep);
135			if (!ep)
136				break;
137
138			/*
139			 * No need to deal with input ports, processing for as
140			 * processing for output ports will deal with them.
141			 */
142			if (of_find_property(ep, "slave-mode", NULL))
143				continue;
144
145			/* Get a handle on the local endpoint */
146			ret = of_graph_parse_endpoint(ep, &endpoint);
147
148			if (ret)
149				continue;
150
151			/* The local out port number */
152			pdata->outports[i] = endpoint.id;
153
154			/*
155			 * Get a handle on the remote port and parent
156			 * attached to it.
157			 */
158			rparent = of_graph_get_remote_port_parent(ep);
159			rport = of_graph_get_remote_port(ep);
160
161			if (!rparent || !rport)
162				continue;
163
164			if (of_graph_parse_endpoint(rport, &rendpoint))
165				continue;
166
167			rdev = of_coresight_get_endpoint_device(rparent);
168			if (!rdev)
169				continue;
170
171			pdata->child_names[i] = dev_name(rdev);
172			pdata->child_ports[i] = rendpoint.id;
173
174			i++;
175		} while (ep);
176	}
177
178	/* Affinity defaults to CPU0 */
179	pdata->cpu = 0;
180	dn = of_parse_phandle(node, "cpu", 0);
181	for (cpu = 0; dn && cpu < nr_cpu_ids; cpu++) {
182		if (dn == of_get_cpu_node(cpu, NULL)) {
183			pdata->cpu = cpu;
184			break;
185		}
186	}
187
188	return pdata;
189}
190EXPORT_SYMBOL_GPL(of_get_coresight_platform_data);