| 1 | /* |
| 2 | * rmobile power management support |
| 3 | * |
| 4 | * Copyright (C) 2012 Renesas Solutions Corp. |
| 5 | * Copyright (C) 2012 Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> |
| 6 | * Copyright (C) 2014 Glider bvba |
| 7 | * |
| 8 | * based on pm-sh7372.c |
| 9 | * Copyright (C) 2011 Magnus Damm |
| 10 | * |
| 11 | * This file is subject to the terms and conditions of the GNU General Public |
| 12 | * License. See the file "COPYING" in the main directory of this archive |
| 13 | * for more details. |
| 14 | */ |
| 15 | #include <linux/console.h> |
| 16 | #include <linux/delay.h> |
| 17 | #include <linux/of.h> |
| 18 | #include <linux/of_address.h> |
| 19 | #include <linux/of_platform.h> |
| 20 | #include <linux/platform_device.h> |
| 21 | #include <linux/pm.h> |
| 22 | #include <linux/pm_clock.h> |
| 23 | #include <linux/slab.h> |
| 24 | |
| 25 | #include <asm/io.h> |
| 26 | |
| 27 | #include "pm-rmobile.h" |
| 28 | |
| 29 | /* SYSC */ |
| 30 | #define SPDCR 0x08 /* SYS Power Down Control Register */ |
| 31 | #define SWUCR 0x14 /* SYS Wakeup Control Register */ |
| 32 | #define PSTR 0x80 /* Power Status Register */ |
| 33 | |
| 34 | #define PSTR_RETRIES 100 |
| 35 | #define PSTR_DELAY_US 10 |
| 36 | |
| 37 | static inline |
| 38 | struct rmobile_pm_domain *to_rmobile_pd(struct generic_pm_domain *d) |
| 39 | { |
| 40 | return container_of(d, struct rmobile_pm_domain, genpd); |
| 41 | } |
| 42 | |
| 43 | static int rmobile_pd_power_down(struct generic_pm_domain *genpd) |
| 44 | { |
| 45 | struct rmobile_pm_domain *rmobile_pd = to_rmobile_pd(genpd); |
| 46 | unsigned int mask; |
| 47 | |
| 48 | if (rmobile_pd->bit_shift == ~0) |
| 49 | return -EBUSY; |
| 50 | |
| 51 | mask = BIT(rmobile_pd->bit_shift); |
| 52 | if (rmobile_pd->suspend) { |
| 53 | int ret = rmobile_pd->suspend(); |
| 54 | |
| 55 | if (ret) |
| 56 | return ret; |
| 57 | } |
| 58 | |
| 59 | if (__raw_readl(rmobile_pd->base + PSTR) & mask) { |
| 60 | unsigned int retry_count; |
| 61 | __raw_writel(mask, rmobile_pd->base + SPDCR); |
| 62 | |
| 63 | for (retry_count = PSTR_RETRIES; retry_count; retry_count--) { |
| 64 | if (!(__raw_readl(rmobile_pd->base + SPDCR) & mask)) |
| 65 | break; |
| 66 | cpu_relax(); |
| 67 | } |
| 68 | } |
| 69 | |
| 70 | if (!rmobile_pd->no_debug) |
| 71 | pr_debug("%s: Power off, 0x%08x -> PSTR = 0x%08x\n", |
| 72 | genpd->name, mask, |
| 73 | __raw_readl(rmobile_pd->base + PSTR)); |
| 74 | |
| 75 | return 0; |
| 76 | } |
| 77 | |
| 78 | static int __rmobile_pd_power_up(struct rmobile_pm_domain *rmobile_pd, |
| 79 | bool do_resume) |
| 80 | { |
| 81 | unsigned int mask; |
| 82 | unsigned int retry_count; |
| 83 | int ret = 0; |
| 84 | |
| 85 | if (rmobile_pd->bit_shift == ~0) |
| 86 | return 0; |
| 87 | |
| 88 | mask = BIT(rmobile_pd->bit_shift); |
| 89 | if (__raw_readl(rmobile_pd->base + PSTR) & mask) |
| 90 | goto out; |
| 91 | |
| 92 | __raw_writel(mask, rmobile_pd->base + SWUCR); |
| 93 | |
| 94 | for (retry_count = 2 * PSTR_RETRIES; retry_count; retry_count--) { |
| 95 | if (!(__raw_readl(rmobile_pd->base + SWUCR) & mask)) |
| 96 | break; |
| 97 | if (retry_count > PSTR_RETRIES) |
| 98 | udelay(PSTR_DELAY_US); |
| 99 | else |
| 100 | cpu_relax(); |
| 101 | } |
| 102 | if (!retry_count) |
| 103 | ret = -EIO; |
| 104 | |
| 105 | if (!rmobile_pd->no_debug) |
| 106 | pr_debug("%s: Power on, 0x%08x -> PSTR = 0x%08x\n", |
| 107 | rmobile_pd->genpd.name, mask, |
| 108 | __raw_readl(rmobile_pd->base + PSTR)); |
| 109 | |
| 110 | out: |
| 111 | if (ret == 0 && rmobile_pd->resume && do_resume) |
| 112 | rmobile_pd->resume(); |
| 113 | |
| 114 | return ret; |
| 115 | } |
| 116 | |
| 117 | static int rmobile_pd_power_up(struct generic_pm_domain *genpd) |
| 118 | { |
| 119 | return __rmobile_pd_power_up(to_rmobile_pd(genpd), true); |
| 120 | } |
| 121 | |
| 122 | static bool rmobile_pd_active_wakeup(struct device *dev) |
| 123 | { |
| 124 | return true; |
| 125 | } |
| 126 | |
| 127 | static int rmobile_pd_attach_dev(struct generic_pm_domain *domain, |
| 128 | struct device *dev) |
| 129 | { |
| 130 | int error; |
| 131 | |
| 132 | error = pm_clk_create(dev); |
| 133 | if (error) { |
| 134 | dev_err(dev, "pm_clk_create failed %d\n", error); |
| 135 | return error; |
| 136 | } |
| 137 | |
| 138 | error = pm_clk_add(dev, NULL); |
| 139 | if (error) { |
| 140 | dev_err(dev, "pm_clk_add failed %d\n", error); |
| 141 | goto fail; |
| 142 | } |
| 143 | |
| 144 | return 0; |
| 145 | |
| 146 | fail: |
| 147 | pm_clk_destroy(dev); |
| 148 | return error; |
| 149 | } |
| 150 | |
| 151 | static void rmobile_pd_detach_dev(struct generic_pm_domain *domain, |
| 152 | struct device *dev) |
| 153 | { |
| 154 | pm_clk_destroy(dev); |
| 155 | } |
| 156 | |
| 157 | static void rmobile_init_pm_domain(struct rmobile_pm_domain *rmobile_pd) |
| 158 | { |
| 159 | struct generic_pm_domain *genpd = &rmobile_pd->genpd; |
| 160 | struct dev_power_governor *gov = rmobile_pd->gov; |
| 161 | |
| 162 | genpd->flags = GENPD_FLAG_PM_CLK; |
| 163 | pm_genpd_init(genpd, gov ? : &simple_qos_governor, false); |
| 164 | genpd->dev_ops.active_wakeup = rmobile_pd_active_wakeup; |
| 165 | genpd->power_off = rmobile_pd_power_down; |
| 166 | genpd->power_on = rmobile_pd_power_up; |
| 167 | genpd->attach_dev = rmobile_pd_attach_dev; |
| 168 | genpd->detach_dev = rmobile_pd_detach_dev; |
| 169 | __rmobile_pd_power_up(rmobile_pd, false); |
| 170 | } |
| 171 | |
| 172 | static int rmobile_pd_suspend_busy(void) |
| 173 | { |
| 174 | /* |
| 175 | * This domain should not be turned off. |
| 176 | */ |
| 177 | return -EBUSY; |
| 178 | } |
| 179 | |
| 180 | static int rmobile_pd_suspend_console(void) |
| 181 | { |
| 182 | /* |
| 183 | * Serial consoles make use of SCIF hardware located in this domain, |
| 184 | * hence keep the power domain on if "no_console_suspend" is set. |
| 185 | */ |
| 186 | return console_suspend_enabled ? 0 : -EBUSY; |
| 187 | } |
| 188 | |
| 189 | enum pd_types { |
| 190 | PD_NORMAL, |
| 191 | PD_CPU, |
| 192 | PD_CONSOLE, |
| 193 | PD_DEBUG, |
| 194 | PD_MEMCTL, |
| 195 | }; |
| 196 | |
| 197 | #define MAX_NUM_SPECIAL_PDS 16 |
| 198 | |
| 199 | static struct special_pd { |
| 200 | struct device_node *pd; |
| 201 | enum pd_types type; |
| 202 | } special_pds[MAX_NUM_SPECIAL_PDS] __initdata; |
| 203 | |
| 204 | static unsigned int num_special_pds __initdata; |
| 205 | |
| 206 | static const struct of_device_id special_ids[] __initconst = { |
| 207 | { .compatible = "arm,coresight-etm3x", .data = (void *)PD_DEBUG }, |
| 208 | { .compatible = "renesas,dbsc-r8a73a4", .data = (void *)PD_MEMCTL, }, |
| 209 | { .compatible = "renesas,dbsc3-r8a7740", .data = (void *)PD_MEMCTL, }, |
| 210 | { .compatible = "renesas,sbsc-sh73a0", .data = (void *)PD_MEMCTL, }, |
| 211 | { /* sentinel */ }, |
| 212 | }; |
| 213 | |
| 214 | static void __init add_special_pd(struct device_node *np, enum pd_types type) |
| 215 | { |
| 216 | unsigned int i; |
| 217 | struct device_node *pd; |
| 218 | |
| 219 | pd = of_parse_phandle(np, "power-domains", 0); |
| 220 | if (!pd) |
| 221 | return; |
| 222 | |
| 223 | for (i = 0; i < num_special_pds; i++) |
| 224 | if (pd == special_pds[i].pd && type == special_pds[i].type) { |
| 225 | of_node_put(pd); |
| 226 | return; |
| 227 | } |
| 228 | |
| 229 | if (num_special_pds == ARRAY_SIZE(special_pds)) { |
| 230 | pr_warn("Too many special PM domains\n"); |
| 231 | of_node_put(pd); |
| 232 | return; |
| 233 | } |
| 234 | |
| 235 | pr_debug("Special PM domain %s type %d for %s\n", pd->name, type, |
| 236 | np->full_name); |
| 237 | |
| 238 | special_pds[num_special_pds].pd = pd; |
| 239 | special_pds[num_special_pds].type = type; |
| 240 | num_special_pds++; |
| 241 | } |
| 242 | |
| 243 | static void __init get_special_pds(void) |
| 244 | { |
| 245 | struct device_node *np; |
| 246 | const struct of_device_id *id; |
| 247 | |
| 248 | /* PM domains containing CPUs */ |
| 249 | for_each_node_by_type(np, "cpu") |
| 250 | add_special_pd(np, PD_CPU); |
| 251 | |
| 252 | /* PM domain containing console */ |
| 253 | if (of_stdout) |
| 254 | add_special_pd(of_stdout, PD_CONSOLE); |
| 255 | |
| 256 | /* PM domains containing other special devices */ |
| 257 | for_each_matching_node_and_match(np, special_ids, &id) |
| 258 | add_special_pd(np, (enum pd_types)id->data); |
| 259 | } |
| 260 | |
| 261 | static void __init put_special_pds(void) |
| 262 | { |
| 263 | unsigned int i; |
| 264 | |
| 265 | for (i = 0; i < num_special_pds; i++) |
| 266 | of_node_put(special_pds[i].pd); |
| 267 | } |
| 268 | |
| 269 | static enum pd_types __init pd_type(const struct device_node *pd) |
| 270 | { |
| 271 | unsigned int i; |
| 272 | |
| 273 | for (i = 0; i < num_special_pds; i++) |
| 274 | if (pd == special_pds[i].pd) |
| 275 | return special_pds[i].type; |
| 276 | |
| 277 | return PD_NORMAL; |
| 278 | } |
| 279 | |
| 280 | static void __init rmobile_setup_pm_domain(struct device_node *np, |
| 281 | struct rmobile_pm_domain *pd) |
| 282 | { |
| 283 | const char *name = pd->genpd.name; |
| 284 | |
| 285 | switch (pd_type(np)) { |
| 286 | case PD_CPU: |
| 287 | /* |
| 288 | * This domain contains the CPU core and therefore it should |
| 289 | * only be turned off if the CPU is not in use. |
| 290 | */ |
| 291 | pr_debug("PM domain %s contains CPU\n", name); |
| 292 | pd->gov = &pm_domain_always_on_gov; |
| 293 | pd->suspend = rmobile_pd_suspend_busy; |
| 294 | break; |
| 295 | |
| 296 | case PD_CONSOLE: |
| 297 | pr_debug("PM domain %s contains serial console\n", name); |
| 298 | pd->gov = &pm_domain_always_on_gov; |
| 299 | pd->suspend = rmobile_pd_suspend_console; |
| 300 | break; |
| 301 | |
| 302 | case PD_DEBUG: |
| 303 | /* |
| 304 | * This domain contains the Coresight-ETM hardware block and |
| 305 | * therefore it should only be turned off if the debug module |
| 306 | * is not in use. |
| 307 | */ |
| 308 | pr_debug("PM domain %s contains Coresight-ETM\n", name); |
| 309 | pd->gov = &pm_domain_always_on_gov; |
| 310 | pd->suspend = rmobile_pd_suspend_busy; |
| 311 | break; |
| 312 | |
| 313 | case PD_MEMCTL: |
| 314 | /* |
| 315 | * This domain contains a memory-controller and therefore it |
| 316 | * should only be turned off if memory is not in use. |
| 317 | */ |
| 318 | pr_debug("PM domain %s contains MEMCTL\n", name); |
| 319 | pd->gov = &pm_domain_always_on_gov; |
| 320 | pd->suspend = rmobile_pd_suspend_busy; |
| 321 | break; |
| 322 | |
| 323 | case PD_NORMAL: |
| 324 | break; |
| 325 | } |
| 326 | |
| 327 | rmobile_init_pm_domain(pd); |
| 328 | } |
| 329 | |
| 330 | static int __init rmobile_add_pm_domains(void __iomem *base, |
| 331 | struct device_node *parent, |
| 332 | struct generic_pm_domain *genpd_parent) |
| 333 | { |
| 334 | struct device_node *np; |
| 335 | |
| 336 | for_each_child_of_node(parent, np) { |
| 337 | struct rmobile_pm_domain *pd; |
| 338 | u32 idx = ~0; |
| 339 | |
| 340 | if (of_property_read_u32(np, "reg", &idx)) { |
| 341 | /* always-on domain */ |
| 342 | } |
| 343 | |
| 344 | pd = kzalloc(sizeof(*pd), GFP_KERNEL); |
| 345 | if (!pd) |
| 346 | return -ENOMEM; |
| 347 | |
| 348 | pd->genpd.name = np->name; |
| 349 | pd->base = base; |
| 350 | pd->bit_shift = idx; |
| 351 | |
| 352 | rmobile_setup_pm_domain(np, pd); |
| 353 | if (genpd_parent) |
| 354 | pm_genpd_add_subdomain(genpd_parent, &pd->genpd); |
| 355 | of_genpd_add_provider_simple(np, &pd->genpd); |
| 356 | |
| 357 | rmobile_add_pm_domains(base, np, &pd->genpd); |
| 358 | } |
| 359 | return 0; |
| 360 | } |
| 361 | |
| 362 | static int __init rmobile_init_pm_domains(void) |
| 363 | { |
| 364 | struct device_node *np, *pmd; |
| 365 | bool scanned = false; |
| 366 | void __iomem *base; |
| 367 | int ret = 0; |
| 368 | |
| 369 | for_each_compatible_node(np, NULL, "renesas,sysc-rmobile") { |
| 370 | base = of_iomap(np, 0); |
| 371 | if (!base) { |
| 372 | pr_warn("%s cannot map reg 0\n", np->full_name); |
| 373 | continue; |
| 374 | } |
| 375 | |
| 376 | pmd = of_get_child_by_name(np, "pm-domains"); |
| 377 | if (!pmd) { |
| 378 | pr_warn("%s lacks pm-domains node\n", np->full_name); |
| 379 | continue; |
| 380 | } |
| 381 | |
| 382 | if (!scanned) { |
| 383 | /* Find PM domains containing special blocks */ |
| 384 | get_special_pds(); |
| 385 | scanned = true; |
| 386 | } |
| 387 | |
| 388 | ret = rmobile_add_pm_domains(base, pmd, NULL); |
| 389 | of_node_put(pmd); |
| 390 | if (ret) { |
| 391 | of_node_put(np); |
| 392 | break; |
| 393 | } |
| 394 | } |
| 395 | |
| 396 | put_special_pds(); |
| 397 | |
| 398 | return ret; |
| 399 | } |
| 400 | |
| 401 | core_initcall(rmobile_init_pm_domains); |