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) 2015-2018 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 /**
  27  * struct zynqmp_pm_domain - Wrapper around struct generic_pm_domain
  28  * @gpd:                Generic power domain
  29  * @node_id:            PM node ID corresponding to device inside PM domain
  30  * @flags:              ZynqMP PM domain flags
  31  */
  32 struct zynqmp_pm_domain {
  33         struct generic_pm_domain gpd;
  34         u32 node_id;
  35         u8 flags;
  36 };
  37
  38 /**
  39  * zynqmp_gpd_is_active_wakeup_path() - Check if device is in wakeup source
  40  *                                      path
  41  * @dev:        Device to check for wakeup source path
  42  * @not_used:   Data member (not required)
  43  *
  44  * This function is checks device's child hierarchy and checks if any device is
  45  * set as wakeup source.
  46  *
  47  * Return: 1 if device is in wakeup source path else 0
  48  */
  49 static int zynqmp_gpd_is_active_wakeup_path(struct device *dev, void *not_used)
  50 {
  51         int may_wakeup;
  52
  53         may_wakeup = device_may_wakeup(dev);
  54         if (may_wakeup)
  55                 return may_wakeup;
  56
  57         return device_for_each_child(dev, NULL,
  58                         zynqmp_gpd_is_active_wakeup_path);
  59 }
  60
  61 /**
  62  * zynqmp_gpd_power_on() - Power on PM domain
  63  * @domain:     Generic PM domain
  64  *
  65  * This function is called before devices inside a PM domain are resumed, to
  66  * power on PM domain.
  67  *
  68  * Return: 0 on success, error code otherwise
  69  */
  70 static int zynqmp_gpd_power_on(struct generic_pm_domain *domain)
  71 {
  72         int ret;
  73         struct zynqmp_pm_domain *pd;
  74         const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops();
  75
  76         if (!eemi_ops || !eemi_ops->set_requirement)
  77                 return -ENXIO;
  78
  79         pd = container_of(domain, struct zynqmp_pm_domain, gpd);
  80         ret = eemi_ops->set_requirement(pd->node_id,
  81                                         ZYNQMP_PM_CAPABILITY_ACCESS,
  82                                         ZYNQMP_PM_MAX_QOS,
  83                                         ZYNQMP_PM_REQUEST_ACK_BLOCKING);
  84         if (ret) {
  85                 pr_err("%s() %s set requirement for node %d failed: %d\n",
  86                        __func__, domain->name, pd->node_id, ret);
  87                 return ret;
  88         }
  89
  90         pr_debug("%s() Powered on %s domain\n", __func__, domain->name);
  91         return 0;
  92 }
  93
  94 /**
  95  * zynqmp_gpd_power_off() - Power off PM domain
  96  * @domain:     Generic PM domain
  97  *
  98  * This function is called after devices inside a PM domain are suspended, to
  99  * power off PM domain.
 100  *
 101  * Return: 0 on success, error code otherwise
 102  */
 103 static int zynqmp_gpd_power_off(struct generic_pm_domain *domain)
 104 {
 105         int ret;
 106         struct pm_domain_data *pdd, *tmp;
 107         struct zynqmp_pm_domain *pd;
 108         u32 capabilities = 0;
 109         bool may_wakeup;
 110         const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops();
 111
 112         if (!eemi_ops || !eemi_ops->set_requirement)
 113                 return -ENXIO;
 114
 115         pd = container_of(domain, struct zynqmp_pm_domain, gpd);
 116
 117         /* If domain is already released there is nothing to be done */
 118         if (!(pd->flags & ZYNQMP_PM_DOMAIN_REQUESTED)) {
 119                 pr_debug("%s() %s domain is already released\n",
 120                          __func__, domain->name);
 121                 return 0;
 122         }
 123
 124         list_for_each_entry_safe(pdd, tmp, &domain->dev_list, list_node) {
 125                 /* If device is in wakeup path, set capability to WAKEUP */
 126                 may_wakeup = zynqmp_gpd_is_active_wakeup_path(pdd->dev, NULL);
 127                 if (may_wakeup) {
 128                         dev_dbg(pdd->dev, "device is in wakeup path in %s\n",
 129                                 domain->name);
 130                         capabilities = ZYNQMP_PM_CAPABILITY_WAKEUP;
 131                         break;
 132                 }
 133         }
 134
 135         ret = eemi_ops->set_requirement(pd->node_id, capabilities, 0,
 136                                         ZYNQMP_PM_REQUEST_ACK_NO);
 137         /**
 138          * If powering down of any node inside this domain fails,
 139          * report and return the error
 140          */
 141         if (ret) {
 142                 pr_err("%s() %s set requirement for node %d failed: %d\n",
 143                        __func__, domain->name, pd->node_id, ret);
 144                 return ret;
 145         }
 146
 147         pr_debug("%s() Powered off %s domain\n", __func__, domain->name);
 148         return 0;
 149 }
 150
 151 /**
 152  * zynqmp_gpd_attach_dev() - Attach device to the PM domain
 153  * @domain:     Generic PM domain
 154  * @dev:        Device to attach
 155  *
 156  * Return: 0 on success, error code otherwise
 157  */
 158 static int zynqmp_gpd_attach_dev(struct generic_pm_domain *domain,
 159                                  struct device *dev)
 160 {
 161         int ret;
 162         struct zynqmp_pm_domain *pd;
 163         const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops();
 164
 165         if (!eemi_ops || !eemi_ops->request_node)
 166                 return -ENXIO;
 167
 168         pd = container_of(domain, struct zynqmp_pm_domain, gpd);
 169
 170         /* If this is not the first device to attach there is nothing to do */
 171         if (domain->device_count)
 172                 return 0;
 173
 174         ret = eemi_ops->request_node(pd->node_id, 0, 0,
 175                                      ZYNQMP_PM_REQUEST_ACK_BLOCKING);
 176         /* If requesting a node fails print and return the error */
 177         if (ret) {
 178                 pr_err("%s() %s request failed for node %d: %d\n",
 179                        __func__, domain->name, pd->node_id, ret);
 180                 return ret;
 181         }
 182
 183         pd->flags |= ZYNQMP_PM_DOMAIN_REQUESTED;
 184
 185         pr_debug("%s() %s attached to %s domain\n", __func__,
 186                  dev_name(dev), domain->name);
 187         return 0;
 188 }
 189
 190 /**
 191  * zynqmp_gpd_detach_dev() - Detach device from the PM domain
 192  * @domain:     Generic PM domain
 193  * @dev:        Device to detach
 194  */
 195 static void zynqmp_gpd_detach_dev(struct generic_pm_domain *domain,
 196                                   struct device *dev)
 197 {
 198         int ret;
 199         struct zynqmp_pm_domain *pd;
 200         const struct zynqmp_eemi_ops *eemi_ops = zynqmp_pm_get_eemi_ops();
 201
 202         if (!eemi_ops || !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         pd = devm_kcalloc(dev, ZYNQMP_NUM_DOMAINS, sizeof(*pd), GFP_KERNEL);
 270         if (!pd)
 271                 return -ENOMEM;
 272
 273         zynqmp_pd_data = devm_kzalloc(dev, sizeof(*zynqmp_pd_data), GFP_KERNEL);
 274         if (!zynqmp_pd_data)
 275                 return -ENOMEM;
 276
 277         zynqmp_pd_data->xlate = zynqmp_gpd_xlate;
 278
 279         domains = devm_kcalloc(dev, ZYNQMP_NUM_DOMAINS, sizeof(*domains),
 280                                GFP_KERNEL);
 281         if (!domains)
 282                 return -ENOMEM;
 283
 284         for (i = 0; i < ZYNQMP_NUM_DOMAINS; i++, pd++) {
 285                 pd->node_id = 0;
 286                 pd->gpd.name = kasprintf(GFP_KERNEL, "domain%d", i);
 287                 pd->gpd.power_off = zynqmp_gpd_power_off;
 288                 pd->gpd.power_on = zynqmp_gpd_power_on;
 289                 pd->gpd.attach_dev = zynqmp_gpd_attach_dev;
 290                 pd->gpd.detach_dev = zynqmp_gpd_detach_dev;
 291
 292                 domains[i] = &pd->gpd;
 293
 294                 /* Mark all PM domains as initially powered off */
 295                 pm_genpd_init(&pd->gpd, NULL, true);
 296         }
 297
 298         zynqmp_pd_data->domains = domains;
 299         zynqmp_pd_data->num_domains = ZYNQMP_NUM_DOMAINS;
 300         of_genpd_add_provider_onecell(dev->parent->of_node, zynqmp_pd_data);
 301
 302         return 0;
 303 }
 304
 305 static int zynqmp_gpd_remove(struct platform_device *pdev)
 306 {
 307         of_genpd_del_provider(pdev->dev.parent->of_node);
 308
 309         return 0;
 310 }
 311
 312 static struct platform_driver zynqmp_power_domain_driver = {
 313         .driver = {
 314                 .name = "zynqmp_power_controller",
 315         },
 316         .probe = zynqmp_gpd_probe,
 317         .remove = zynqmp_gpd_remove,
 318 };
 319 module_platform_driver(zynqmp_power_domain_driver);
 320
 321 MODULE_ALIAS("platform:zynqmp_power_controller");