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 (!dn || !of_device_is_available(dn)) {
 100                         dev_warn(dev, "Missing property %s, skip scaling %s\n",
 101                                  adj->phandle_name, node->name);
 102                         return 0;
 103                 }
 104
 105                 pdev = of_find_device_by_node(dn);
 106                 of_node_put(dn);
 107                 if (!pdev) {
 108                         dev_warn(dev, "node %s[%d] missing device for %pOF\n",
 109                                  node->name, node->id, dn);
 110                         return -EPROBE_DEFER;
 111                 }
 112                 node_data->qos_dev = &pdev->dev;
 113                 dev_dbg(dev, "node %s[%d] has device node %pOF\n",
 114                         node->name, node->id, dn);
 115         }
 116
 117         return dev_pm_qos_add_request(node_data->qos_dev,
 118                                       &node_data->qos_req,
 119                                       DEV_PM_QOS_MIN_FREQUENCY, 0);
 120 }
 121
 122 static struct icc_node *imx_icc_node_add(struct icc_provider *provider,
 123                                          const struct imx_icc_node_desc *node_desc)
 124 {
 125         struct device *dev = provider->dev;
 126         struct imx_icc_node *node_data;
 127         struct icc_node *node;
 128         int ret;
 129
 130         node = icc_node_create(node_desc->id);
 131         if (IS_ERR(node)) {
 132                 dev_err(dev, "failed to create node %d\n", node_desc->id);
 133                 return node;
 134         }
 135
 136         if (node->data) {
 137                 dev_err(dev, "already created node %s id=%d\n",
 138                         node_desc->name, node_desc->id);
 139                 return ERR_PTR(-EEXIST);
 140         }
 141
 142         node_data = devm_kzalloc(dev, sizeof(*node_data), GFP_KERNEL);
 143         if (!node_data) {
 144                 icc_node_destroy(node->id);
 145                 return ERR_PTR(-ENOMEM);
 146         }
 147
 148         node->name = node_desc->name;
 149         node->data = node_data;
 150         node_data->desc = node_desc;
 151         icc_node_add(node, provider);
 152
 153         if (node_desc->adj) {
 154                 ret = imx_icc_node_init_qos(provider, node);
 155                 if (ret < 0) {
 156                         imx_icc_node_destroy(node);
 157                         return ERR_PTR(ret);
 158                 }
 159         }
 160
 161         return node;
 162 }
 163
 164 static void imx_icc_unregister_nodes(struct icc_provider *provider)
 165 {
 166         struct icc_node *node, *tmp;
 167
 168         list_for_each_entry_safe(node, tmp, &provider->nodes, node_list)
 169                 imx_icc_node_destroy(node);
 170 }
 171
 172 static int imx_icc_register_nodes(struct icc_provider *provider,
 173                                   const struct imx_icc_node_desc *descs,
 174                                   int count)
 175 {
 176         struct icc_onecell_data *provider_data = provider->data;
 177         int ret;
 178         int i;
 179
 180         for (i = 0; i < count; i++) {
 181                 struct icc_node *node;
 182                 const struct imx_icc_node_desc *node_desc = &descs[i];
 183                 size_t j;
 184
 185                 node = imx_icc_node_add(provider, node_desc);
 186                 if (IS_ERR(node)) {
 187                         ret = dev_err_probe(provider->dev, PTR_ERR(node),
 188                                             "failed to add %s\n", node_desc->name);
 189                         goto err;
 190                 }
 191                 provider_data->nodes[node->id] = node;
 192
 193                 for (j = 0; j < node_desc->num_links; j++) {
 194                         ret = icc_link_create(node, node_desc->links[j]);
 195                         if (ret) {
 196                                 dev_err(provider->dev, "failed to link node %d to %d: %d\n",
 197                                         node->id, node_desc->links[j], ret);
 198                                 goto err;
 199                         }
 200                 }
 201         }
 202
 203         return 0;
 204
 205 err:
 206         imx_icc_unregister_nodes(provider);
 207
 208         return ret;
 209 }
 210
 211 static int get_max_node_id(struct imx_icc_node_desc *nodes, int nodes_count)
 212 {
 213         int i, ret = 0;
 214
 215         for (i = 0; i < nodes_count; ++i)
 216                 if (nodes[i].id > ret)
 217                         ret = nodes[i].id;
 218
 219         return ret;
 220 }
 221
 222 int imx_icc_register(struct platform_device *pdev,
 223                      struct imx_icc_node_desc *nodes, int nodes_count)
 224 {
 225         struct device *dev = &pdev->dev;
 226         struct icc_onecell_data *data;
 227         struct icc_provider *provider;
 228         int max_node_id;
 229         int ret;
 230
 231         /* icc_onecell_data is indexed by node_id, unlike nodes param */
 232         max_node_id = get_max_node_id(nodes, nodes_count);
 233         data = devm_kzalloc(dev, struct_size(data, nodes, max_node_id),
 234                             GFP_KERNEL);
 235         if (!data)
 236                 return -ENOMEM;
 237         data->num_nodes = max_node_id;
 238
 239         provider = devm_kzalloc(dev, sizeof(*provider), GFP_KERNEL);
 240         if (!provider)
 241                 return -ENOMEM;
 242         provider->set = imx_icc_set;
 243         provider->aggregate = icc_std_aggregate;
 244         provider->xlate = of_icc_xlate_onecell;
 245         provider->data = data;
 246         provider->dev = dev->parent;
 247         platform_set_drvdata(pdev, provider);
 248
 249         ret = icc_provider_add(provider);
 250         if (ret) {
 251                 dev_err(dev, "error adding interconnect provider: %d\n", ret);
 252                 return ret;
 253         }
 254
 255         ret = imx_icc_register_nodes(provider, nodes, nodes_count);
 256         if (ret)
 257                 goto provider_del;
 258
 259         return 0;
 260
 261 provider_del:
 262         icc_provider_del(provider);
 263         return ret;
 264 }
 265 EXPORT_SYMBOL_GPL(imx_icc_register);
 266
 267 int imx_icc_unregister(struct platform_device *pdev)
 268 {
 269         struct icc_provider *provider = platform_get_drvdata(pdev);
 270
 271         imx_icc_unregister_nodes(provider);
 272
 273         return icc_provider_del(provider);
 274 }
 275 EXPORT_SYMBOL_GPL(imx_icc_unregister);
 276
 277 MODULE_LICENSE("GPL v2");