1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Interconnect framework driver for i.MX SoC
4 *
5 * Copyright (c) 2019, BayLibre
6 * Copyright (c) 2019-2020, NXP
7 * Author: Alexandre Bailon <abailon@baylibre.com>
8 * Author: Leonard Crestez <leonard.crestez@nxp.com>
9 */
10
11#include <linux/device.h>
12#include <linux/interconnect-provider.h>
13#include <linux/module.h>
14#include <linux/of.h>
15#include <linux/of_platform.h>
16#include <linux/platform_device.h>
17#include <linux/pm_qos.h>
18
19#include "imx.h"
20
21/* private icc_node data */
22struct imx_icc_node {
23	const struct imx_icc_node_desc *desc;
24	struct device *qos_dev;
25	struct dev_pm_qos_request qos_req;
26};
27
28static int imx_icc_node_set(struct icc_node *node)
29{
30	struct device *dev = node->provider->dev;
31	struct imx_icc_node *node_data = node->data;
32	u64 freq;
33
34	if (!node_data->qos_dev)
35		return 0;
36
37	freq = (node->avg_bw + node->peak_bw) * node_data->desc->adj->bw_mul;
38	do_div(freq, node_data->desc->adj->bw_div);
39	dev_dbg(dev, "node %s device %s avg_bw %ukBps peak_bw %ukBps min_freq %llukHz\n",
40		node->name, dev_name(node_data->qos_dev),
41		node->avg_bw, node->peak_bw, freq);
42
43	if (freq > S32_MAX) {
44		dev_err(dev, "%s can't request more than S32_MAX freq\n",
45				node->name);
46		return -ERANGE;
47	}
48
49	dev_pm_qos_update_request(&node_data->qos_req, freq);
50
51	return 0;
52}
53
54static int imx_icc_set(struct icc_node *src, struct icc_node *dst)
55{
56	return imx_icc_node_set(dst);
57}
58
59/* imx_icc_node_destroy() - Destroy an imx icc_node, including private data */
60static void imx_icc_node_destroy(struct icc_node *node)
61{
62	struct imx_icc_node *node_data = node->data;
63	int ret;
64
65	if (dev_pm_qos_request_active(&node_data->qos_req)) {
66		ret = dev_pm_qos_remove_request(&node_data->qos_req);
67		if (ret)
68			dev_warn(node->provider->dev,
69				 "failed to remove qos request for %s\n",
70				 dev_name(node_data->qos_dev));
71	}
72
73	put_device(node_data->qos_dev);
74	icc_node_del(node);
75	icc_node_destroy(node->id);
76}
77
78static int imx_icc_node_init_qos(struct icc_provider *provider,
79				 struct icc_node *node)
80{
81	struct imx_icc_node *node_data = node->data;
82	const struct imx_icc_node_adj_desc *adj = node_data->desc->adj;
83	struct device *dev = provider->dev;
84	struct device_node *dn = NULL;
85	struct platform_device *pdev;
86
87	if (adj->main_noc) {
88		node_data->qos_dev = dev;
89		dev_dbg(dev, "icc node %s[%d] is main noc itself\n",
90			node->name, node->id);
91	} else {
92		dn = of_parse_phandle(dev->of_node, adj->phandle_name, 0);
93		if (!dn) {
94			dev_warn(dev, "Failed to parse %s\n",
95				 adj->phandle_name);
96			return -ENODEV;
97		}
98		/* Allow scaling to be disabled on a per-node basis */
99		if (!dn || !of_device_is_available(dn)) {
100			dev_warn(dev, "Missing property %s, skip scaling %s\n",
101				 adj->phandle_name, node->name);
102			of_node_put(dn);
103			return 0;
104		}
105
106		pdev = of_find_device_by_node(dn);
107		of_node_put(dn);
108		if (!pdev) {
109			dev_warn(dev, "node %s[%d] missing device for %pOF\n",
110				 node->name, node->id, dn);
111			return -EPROBE_DEFER;
112		}
113		node_data->qos_dev = &pdev->dev;
114		dev_dbg(dev, "node %s[%d] has device node %pOF\n",
115			node->name, node->id, dn);
116	}
117
118	return dev_pm_qos_add_request(node_data->qos_dev,
119				      &node_data->qos_req,
120				      DEV_PM_QOS_MIN_FREQUENCY, 0);
121}
122
123static struct icc_node *imx_icc_node_add(struct icc_provider *provider,
124					 const struct imx_icc_node_desc *node_desc)
125{
126	struct device *dev = provider->dev;
127	struct imx_icc_node *node_data;
128	struct icc_node *node;
129	int ret;
130
131	node = icc_node_create(node_desc->id);
132	if (IS_ERR(node)) {
133		dev_err(dev, "failed to create node %d\n", node_desc->id);
134		return node;
135	}
136
137	if (node->data) {
138		dev_err(dev, "already created node %s id=%d\n",
139			node_desc->name, node_desc->id);
140		return ERR_PTR(-EEXIST);
141	}
142
143	node_data = devm_kzalloc(dev, sizeof(*node_data), GFP_KERNEL);
144	if (!node_data) {
145		icc_node_destroy(node->id);
146		return ERR_PTR(-ENOMEM);
147	}
148
149	node->name = node_desc->name;
150	node->data = node_data;
151	node_data->desc = node_desc;
152	icc_node_add(node, provider);
153
154	if (node_desc->adj) {
155		ret = imx_icc_node_init_qos(provider, node);
156		if (ret < 0) {
157			imx_icc_node_destroy(node);
158			return ERR_PTR(ret);
159		}
160	}
161
162	return node;
163}
164
165static void imx_icc_unregister_nodes(struct icc_provider *provider)
166{
167	struct icc_node *node, *tmp;
168
169	list_for_each_entry_safe(node, tmp, &provider->nodes, node_list)
170		imx_icc_node_destroy(node);
171}
172
173static int imx_icc_register_nodes(struct icc_provider *provider,
174				  const struct imx_icc_node_desc *descs,
175				  int count)
176{
177	struct icc_onecell_data *provider_data = provider->data;
178	int ret;
179	int i;
180
181	for (i = 0; i < count; i++) {
182		struct icc_node *node;
183		const struct imx_icc_node_desc *node_desc = &descs[i];
184		size_t j;
185
186		node = imx_icc_node_add(provider, node_desc);
187		if (IS_ERR(node)) {
188			ret = dev_err_probe(provider->dev, PTR_ERR(node),
189					    "failed to add %s\n", node_desc->name);
190			goto err;
191		}
192		provider_data->nodes[node->id] = node;
193
194		for (j = 0; j < node_desc->num_links; j++) {
195			ret = icc_link_create(node, node_desc->links[j]);
196			if (ret) {
197				dev_err(provider->dev, "failed to link node %d to %d: %d\n",
198					node->id, node_desc->links[j], ret);
199				goto err;
200			}
201		}
202	}
203
204	return 0;
205
206err:
207	imx_icc_unregister_nodes(provider);
208
209	return ret;
210}
211
212static int get_max_node_id(struct imx_icc_node_desc *nodes, int nodes_count)
213{
214	int i, ret = 0;
215
216	for (i = 0; i < nodes_count; ++i)
217		if (nodes[i].id > ret)
218			ret = nodes[i].id;
219
220	return ret;
221}
222
223int imx_icc_register(struct platform_device *pdev,
224		     struct imx_icc_node_desc *nodes, int nodes_count)
225{
226	struct device *dev = &pdev->dev;
227	struct icc_onecell_data *data;
228	struct icc_provider *provider;
229	int num_nodes;
230	int ret;
231
232	/* icc_onecell_data is indexed by node_id, unlike nodes param */
233	num_nodes = get_max_node_id(nodes, nodes_count) + 1;
234	data = devm_kzalloc(dev, struct_size(data, nodes, num_nodes),
235			    GFP_KERNEL);
236	if (!data)
237		return -ENOMEM;
238	data->num_nodes = num_nodes;
239
240	provider = devm_kzalloc(dev, sizeof(*provider), GFP_KERNEL);
241	if (!provider)
242		return -ENOMEM;
243	provider->set = imx_icc_set;
244	provider->aggregate = icc_std_aggregate;
245	provider->xlate = of_icc_xlate_onecell;
246	provider->data = data;
247	provider->dev = dev->parent;
248	platform_set_drvdata(pdev, provider);
249
250	ret = icc_provider_add(provider);
251	if (ret) {
252		dev_err(dev, "error adding interconnect provider: %d\n", ret);
253		return ret;
254	}
255
256	ret = imx_icc_register_nodes(provider, nodes, nodes_count);
257	if (ret)
258		goto provider_del;
259
260	return 0;
261
262provider_del:
263	icc_provider_del(provider);
264	return ret;
265}
266EXPORT_SYMBOL_GPL(imx_icc_register);
267
268int imx_icc_unregister(struct platform_device *pdev)
269{
270	struct icc_provider *provider = platform_get_drvdata(pdev);
271
272	imx_icc_unregister_nodes(provider);
273
274	return icc_provider_del(provider);
275}
276EXPORT_SYMBOL_GPL(imx_icc_unregister);
277
278MODULE_LICENSE("GPL v2");
279