drivers/interconnect/imx/imx.c

   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 */
  22 struct 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
  28 static 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
  54 static 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 */
  60 static 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
  78 static 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 (!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
 123 static 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
 165 static 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
 173 static 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
 206 err:
 207         imx_icc_unregister_nodes(provider);
 208
 209         return ret;
 210 }
 211
 212 static 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
 223 int 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 max_node_id;
 230         int ret;
 231
 232         /* icc_onecell_data is indexed by node_id, unlike nodes param */
 233         max_node_id = get_max_node_id(nodes, nodes_count);
 234         data = devm_kzalloc(dev, struct_size(data, nodes, max_node_id),
 235                             GFP_KERNEL);
 236         if (!data)
 237                 return -ENOMEM;
 238         data->num_nodes = max_node_id;
 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
 262 provider_del:
 263         icc_provider_del(provider);
 264         return ret;
 265 }
 266 EXPORT_SYMBOL_GPL(imx_icc_register);
 267
 268 int 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 }
 276 EXPORT_SYMBOL_GPL(imx_icc_unregister);
 277
 278 MODULE_LICENSE("GPL v2");