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