drivers/soc/xilinx/zynqmp_pm_domains.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * ZynqMP Generic PM domain support
   4  *
   5  *  Copyright (C) 2015-2019 Xilinx, Inc.
   6  *
   7  *  Davorin Mista <davorin.mista@aggios.com>
   8  *  Jolly Shah <jollys@xilinx.com>
   9  *  Rajan Vaja <rajan.vaja@xilinx.com>
  10  */
  11
  12 #include <linux/err.h>
  13 #include <linux/list.h>
  14 #include <linux/module.h>
  15 #include <linux/of_platform.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/pm_domain.h>
  18 #include <linux/slab.h>
  19
  20 #include <linux/firmware/xlnx-zynqmp.h>
  21
  22 #define ZYNQMP_NUM_DOMAINS              (100)
  23 /* Flag stating if PM nodes mapped to the PM domain has been requested */
  24 #define ZYNQMP_PM_DOMAIN_REQUESTED      BIT(0)
  25
  26 static const struct zynqmp_eemi_ops *eemi_ops;
  27
  28 static int min_capability;
  29
  30 /**
  31  * struct zynqmp_pm_domain - Wrapper around struct generic_pm_domain
  32  * @gpd:                Generic power domain
  33  * @node_id:            PM node ID corresponding to device inside PM domain
  34  * @flags:              ZynqMP PM domain flags
  35  */
  36 struct zynqmp_pm_domain {
  37         struct generic_pm_domain gpd;
  38         u32 node_id;
  39         u8 flags;
  40 };
  41
  42 /**
  43  * zynqmp_gpd_is_active_wakeup_path() - Check if device is in wakeup source
  44  *                                      path
  45  * @dev:        Device to check for wakeup source path
  46  * @not_used:   Data member (not required)
  47  *
  48  * This function is checks device's child hierarchy and checks if any device is
  49  * set as wakeup source.
  50  *
  51  * Return: 1 if device is in wakeup source path else 0
  52  */
  53 static int zynqmp_gpd_is_active_wakeup_path(struct device *dev, void *not_used)
  54 {
  55         int may_wakeup;
  56
  57         may_wakeup = device_may_wakeup(dev);
  58         if (may_wakeup)
  59                 return may_wakeup;
  60
  61         return device_for_each_child(dev, NULL,
  62                         zynqmp_gpd_is_active_wakeup_path);
  63 }
  64
  65 /**
  66  * zynqmp_gpd_power_on() - Power on PM domain
  67  * @domain:     Generic PM domain
  68  *
  69  * This function is called before devices inside a PM domain are resumed, to
  70  * power on PM domain.
  71  *
  72  * Return: 0 on success, error code otherwise
  73  */
  74 static int zynqmp_gpd_power_on(struct generic_pm_domain *domain)
  75 {
  76         int ret;
  77         struct zynqmp_pm_domain *pd;
  78
  79         if (!eemi_ops->set_requirement)
  80                 return -ENXIO;
  81
  82         pd = container_of(domain, struct zynqmp_pm_domain, gpd);
  83         ret = eemi_ops->set_requirement(pd->node_id,
  84                                         ZYNQMP_PM_CAPABILITY_ACCESS,
  85                                         ZYNQMP_PM_MAX_QOS,
  86                                         ZYNQMP_PM_REQUEST_ACK_BLOCKING);
  87         if (ret) {
  88                 pr_err("%s() %s set requirement for node %d failed: %d\n",
  89                        __func__, domain->name, pd->node_id, ret);
  90                 return ret;
  91         }
  92
  93         pr_debug("%s() Powered on %s domain\n", __func__, domain->name);
  94         return 0;
  95 }
  96
  97 /**
  98  * zynqmp_gpd_power_off() - Power off PM domain
  99  * @domain:     Generic PM domain
 100  *
 101  * This function is called after devices inside a PM domain are suspended, to
 102  * power off PM domain.
 103  *
 104  * Return: 0 on success, error code otherwise
 105  */
 106 static int zynqmp_gpd_power_off(struct generic_pm_domain *domain)
 107 {
 108         int ret;
 109         struct pm_domain_data *pdd, *tmp;
 110         struct zynqmp_pm_domain *pd;
 111         u32 capabilities = min_capability;
 112         bool may_wakeup;
 113
 114         if (!eemi_ops->set_requirement)
 115                 return -ENXIO;
 116
 117         pd = container_of(domain, struct zynqmp_pm_domain, gpd);
 118
 119         /* If domain is already released there is nothing to be done */
 120         if (!(pd->flags & ZYNQMP_PM_DOMAIN_REQUESTED)) {
 121                 pr_debug("%s() %s domain is already released\n",
 122                          __func__, domain->name);
 123                 return 0;
 124         }
 125
 126         list_for_each_entry_safe(pdd, tmp, &domain->dev_list, list_node) {
 127                 /* If device is in wakeup path, set capability to WAKEUP */
 128                 may_wakeup = zynqmp_gpd_is_active_wakeup_path(pdd->dev, NULL);
 129                 if (may_wakeup) {
 130                         dev_dbg(pdd->dev, "device is in wakeup path in %s\n",
 131                                 domain->name);
 132                         capabilities = ZYNQMP_PM_CAPABILITY_WAKEUP;
 133                         break;
 134                 }
 135         }
 136
 137         ret = eemi_ops->set_requirement(pd->node_id, capabilities, 0,
 138                                         ZYNQMP_PM_REQUEST_ACK_NO);
 139         /**
 140          * If powering down of any node inside this domain fails,
 141          * report and return the error
 142          */
 143         if (ret) {
 144                 pr_err("%s() %s set requirement for node %d failed: %d\n",
 145                        __func__, domain->name, pd->node_id, ret);
 146                 return ret;
 147         }
 148
 149         pr_debug("%s() Powered off %s domain\n", __func__, domain->name);
 150         return 0;
 151 }
 152
 153 /**
 154  * zynqmp_gpd_attach_dev() - Attach device to the PM domain
 155  * @domain:     Generic PM domain
 156  * @dev:        Device to attach
 157  *
 158  * Return: 0 on success, error code otherwise
 159  */
 160 static int zynqmp_gpd_attach_dev(struct generic_pm_domain *domain,
 161                                  struct device *dev)
 162 {
 163         int ret;
 164         struct zynqmp_pm_domain *pd;
 165
 166         if (!eemi_ops->request_node)
 167                 return -ENXIO;
 168
 169         pd = container_of(domain, struct zynqmp_pm_domain, gpd);
 170
 171         /* If this is not the first device to attach there is nothing to do */
 172         if (domain->device_count)
 173                 return 0;
 174
 175         ret = eemi_ops->request_node(pd->node_id, 0, 0,
 176                                      ZYNQMP_PM_REQUEST_ACK_BLOCKING);
 177         /* If requesting a node fails print and return the error */
 178         if (ret) {
 179                 pr_err("%s() %s request failed for node %d: %d\n",
 180                        __func__, domain->name, pd->node_id, ret);
 181                 return ret;
 182         }
 183
 184         pd->flags |= ZYNQMP_PM_DOMAIN_REQUESTED;
 185
 186         pr_debug("%s() %s attached to %s domain\n", __func__,
 187                  dev_name(dev), domain->name);
 188         return 0;
 189 }
 190
 191 /**
 192  * zynqmp_gpd_detach_dev() - Detach device from the PM domain
 193  * @domain:     Generic PM domain
 194  * @dev:        Device to detach
 195  */
 196 static void zynqmp_gpd_detach_dev(struct generic_pm_domain *domain,
 197                                   struct device *dev)
 198 {
 199         int ret;
 200         struct zynqmp_pm_domain *pd;
 201
 202         if (!eemi_ops->release_node)
 203                 return;
 204
 205         pd = container_of(domain, struct zynqmp_pm_domain, gpd);
 206
 207         /* If this is not the last device to detach there is nothing to do */
 208         if (domain->device_count)
 209                 return;
 210
 211         ret = eemi_ops->release_node(pd->node_id);
 212         /* If releasing a node fails print the error and return */
 213         if (ret) {
 214                 pr_err("%s() %s release failed for node %d: %d\n",
 215                        __func__, domain->name, pd->node_id, ret);
 216                 return;
 217         }
 218
 219         pd->flags &= ~ZYNQMP_PM_DOMAIN_REQUESTED;
 220
 221         pr_debug("%s() %s detached from %s domain\n", __func__,
 222                  dev_name(dev), domain->name);
 223 }
 224
 225 static struct generic_pm_domain *zynqmp_gpd_xlate
 226                                 (struct of_phandle_args *genpdspec, void *data)
 227 {
 228         struct genpd_onecell_data *genpd_data = data;
 229         unsigned int i, idx = genpdspec->args[0];
 230         struct zynqmp_pm_domain *pd;
 231
 232         pd = container_of(genpd_data->domains[0], struct zynqmp_pm_domain, gpd);
 233
 234         if (genpdspec->args_count != 1)
 235                 return ERR_PTR(-EINVAL);
 236
 237         /* Check for existing pm domains */
 238         for (i = 0; i < ZYNQMP_NUM_DOMAINS; i++) {
 239                 if (pd[i].node_id == idx)
 240                         goto done;
 241         }
 242
 243         /**
 244          * Add index in empty node_id of power domain list as no existing
 245          * power domain found for current index.
 246          */
 247         for (i = 0; i < ZYNQMP_NUM_DOMAINS; i++) {
 248                 if (pd[i].node_id == 0) {
 249                         pd[i].node_id = idx;
 250                         break;
 251                 }
 252         }
 253
 254 done:
 255         if (!genpd_data->domains[i] || i == ZYNQMP_NUM_DOMAINS)
 256                 return ERR_PTR(-ENOENT);
 257
 258         return genpd_data->domains[i];
 259 }
 260
 261 static int zynqmp_gpd_probe(struct platform_device *pdev)
 262 {
 263         int i;
 264         struct genpd_onecell_data *zynqmp_pd_data;
 265         struct generic_pm_domain **domains;
 266         struct zynqmp_pm_domain *pd;
 267         struct device *dev = &pdev->dev;
 268
 269         eemi_ops = zynqmp_pm_get_eemi_ops();
 270         if (IS_ERR(eemi_ops))
 271                 return PTR_ERR(eemi_ops);
 272
 273         pd = devm_kcalloc(dev, ZYNQMP_NUM_DOMAINS, sizeof(*pd), GFP_KERNEL);
 274         if (!pd)
 275                 return -ENOMEM;
 276
 277         zynqmp_pd_data = devm_kzalloc(dev, sizeof(*zynqmp_pd_data), GFP_KERNEL);
 278         if (!zynqmp_pd_data)
 279                 return -ENOMEM;
 280
 281         zynqmp_pd_data->xlate = zynqmp_gpd_xlate;
 282
 283         domains = devm_kcalloc(dev, ZYNQMP_NUM_DOMAINS, sizeof(*domains),
 284                                GFP_KERNEL);
 285         if (!domains)
 286                 return -ENOMEM;
 287
 288         if (!of_device_is_compatible(dev->parent->of_node,
 289                                      "xlnx,zynqmp-firmware"))
 290                 min_capability = ZYNQMP_PM_CAPABILITY_UNUSABLE;
 291
 292         for (i = 0; i < ZYNQMP_NUM_DOMAINS; i++, pd++) {
 293                 pd->node_id = 0;
 294                 pd->gpd.name = kasprintf(GFP_KERNEL, "domain%d", i);
 295                 pd->gpd.power_off = zynqmp_gpd_power_off;
 296                 pd->gpd.power_on = zynqmp_gpd_power_on;
 297                 pd->gpd.attach_dev = zynqmp_gpd_attach_dev;
 298                 pd->gpd.detach_dev = zynqmp_gpd_detach_dev;
 299
 300                 domains[i] = &pd->gpd;
 301
 302                 /* Mark all PM domains as initially powered off */
 303                 pm_genpd_init(&pd->gpd, NULL, true);
 304         }
 305
 306         zynqmp_pd_data->domains = domains;
 307         zynqmp_pd_data->num_domains = ZYNQMP_NUM_DOMAINS;
 308         of_genpd_add_provider_onecell(dev->parent->of_node, zynqmp_pd_data);
 309
 310         return 0;
 311 }
 312
 313 static int zynqmp_gpd_remove(struct platform_device *pdev)
 314 {
 315         of_genpd_del_provider(pdev->dev.parent->of_node);
 316
 317         return 0;
 318 }
 319
 320 static struct platform_driver zynqmp_power_domain_driver = {
 321         .driver = {
 322                 .name = "zynqmp_power_controller",
 323         },
 324         .probe = zynqmp_gpd_probe,
 325         .remove = zynqmp_gpd_remove,
 326 };
 327 module_platform_driver(zynqmp_power_domain_driver);
 328
 329 MODULE_ALIAS("platform:zynqmp_power_controller");