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 int ret; 157 158 /* If this is not the first device to attach there is nothing to do */ 159 if (domain->device_count) 160 return 0; 161 162 ret = zynqmp_pm_request_node(pd->node_id, 0, 0, 163 ZYNQMP_PM_REQUEST_ACK_BLOCKING); 164 if (ret) { 165 dev_err(&domain->dev, "%s request failed for node %d: %d\n", 166 domain->name, pd->node_id, ret); 167 return ret; 168 } 169 170 pd->requested = true; 171 172 dev_dbg(&domain->dev, "%s requested PM node id %d\n", 173 dev_name(dev), pd->node_id); 174 175 return 0; 176 } 177 178 /** 179 * zynqmp_gpd_detach_dev() - Detach device from the PM domain 180 * @domain: Generic PM domain 181 * @dev: Device to detach 182 */ 183 static void zynqmp_gpd_detach_dev(struct generic_pm_domain *domain, 184 struct device *dev) 185 { 186 struct zynqmp_pm_domain *pd = to_zynqmp_pm_domain(domain); 187 int ret; 188 189 /* If this is not the last device to detach there is nothing to do */ 190 if (domain->device_count) 191 return; 192 193 ret = zynqmp_pm_release_node(pd->node_id); 194 if (ret) { 195 dev_err(&domain->dev, "failed to release PM node id %d: %d\n", 196 pd->node_id, ret); 197 return; 198 } 199 200 pd->requested = false; 201 202 dev_dbg(&domain->dev, "%s released PM node id %d\n", 203 dev_name(dev), pd->node_id); 204 } 205 206 static struct generic_pm_domain *zynqmp_gpd_xlate 207 (const struct of_phandle_args *genpdspec, void *data) 208 { 209 struct genpd_onecell_data *genpd_data = data; 210 unsigned int i, idx = genpdspec->args[0]; 211 struct zynqmp_pm_domain *pd; 212 213 pd = to_zynqmp_pm_domain(genpd_data->domains[0]); 214 215 if (genpdspec->args_count != 1) 216 return ERR_PTR(-EINVAL); 217 218 /* Check for existing pm domains */ 219 for (i = 0; i < ZYNQMP_NUM_DOMAINS; i++) { 220 if (pd[i].node_id == idx) 221 goto done; 222 } 223 224 /* 225 * Add index in empty node_id of power domain list as no existing 226 * power domain found for current index. 227 */ 228 for (i = 0; i < ZYNQMP_NUM_DOMAINS; i++) { 229 if (pd[i].node_id == 0) { 230 pd[i].node_id = idx; 231 break; 232 } 233 } 234 235 done: 236 if (!genpd_data->domains[i] || i == ZYNQMP_NUM_DOMAINS) 237 return ERR_PTR(-ENOENT); 238 239 return genpd_data->domains[i]; 240 } 241 242 static int zynqmp_gpd_probe(struct platform_device *pdev) 243 { 244 int i; 245 struct genpd_onecell_data *zynqmp_pd_data; 246 struct generic_pm_domain **domains; 247 struct zynqmp_pm_domain *pd; 248 struct device *dev = &pdev->dev; 249 250 pd = devm_kcalloc(dev, ZYNQMP_NUM_DOMAINS, sizeof(*pd), GFP_KERNEL); 251 if (!pd) 252 return -ENOMEM; 253 254 zynqmp_pd_data = devm_kzalloc(dev, sizeof(*zynqmp_pd_data), GFP_KERNEL); 255 if (!zynqmp_pd_data) 256 return -ENOMEM; 257 258 zynqmp_pd_data->xlate = zynqmp_gpd_xlate; 259 260 domains = devm_kcalloc(dev, ZYNQMP_NUM_DOMAINS, sizeof(*domains), 261 GFP_KERNEL); 262 if (!domains) 263 return -ENOMEM; 264 265 if (!of_device_is_compatible(dev->parent->of_node, 266 "xlnx,zynqmp-firmware")) 267 min_capability = ZYNQMP_PM_CAPABILITY_UNUSABLE; 268 269 for (i = 0; i < ZYNQMP_NUM_DOMAINS; i++, pd++) { 270 pd->node_id = 0; 271 pd->gpd.name = kasprintf(GFP_KERNEL, "domain%d", i); 272 pd->gpd.power_off = zynqmp_gpd_power_off; 273 pd->gpd.power_on = zynqmp_gpd_power_on; 274 pd->gpd.attach_dev = zynqmp_gpd_attach_dev; 275 pd->gpd.detach_dev = zynqmp_gpd_detach_dev; 276 277 domains[i] = &pd->gpd; 278 279 /* Mark all PM domains as initially powered off */ 280 pm_genpd_init(&pd->gpd, NULL, true); 281 } 282 283 zynqmp_pd_data->domains = domains; 284 zynqmp_pd_data->num_domains = ZYNQMP_NUM_DOMAINS; 285 of_genpd_add_provider_onecell(dev->parent->of_node, zynqmp_pd_data); 286 287 return 0; 288 } 289 290 static void zynqmp_gpd_remove(struct platform_device *pdev) 291 { 292 of_genpd_del_provider(pdev->dev.parent->of_node); 293 } 294 295 static struct platform_driver zynqmp_power_domain_driver = { 296 .driver = { 297 .name = "zynqmp_power_controller", 298 }, 299 .probe = zynqmp_gpd_probe, 300 .remove = zynqmp_gpd_remove, 301 }; 302 module_platform_driver(zynqmp_power_domain_driver); 303 304 MODULE_ALIAS("platform:zynqmp_power_controller"); 305