1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * OMAP MPUSS low power code 4 * 5 * Copyright (C) 2011 Texas Instruments, Inc. 6 * Santosh Shilimkar <santosh.shilimkar@ti.com> 7 * 8 * OMAP4430 MPUSS mainly consists of dual Cortex-A9 with per-CPU 9 * Local timer and Watchdog, GIC, SCU, PL310 L2 cache controller, 10 * CPU0 and CPU1 LPRM modules. 11 * CPU0, CPU1 and MPUSS each have there own power domain and 12 * hence multiple low power combinations of MPUSS are possible. 13 * 14 * The CPU0 and CPU1 can't support Closed switch Retention (CSWR) 15 * because the mode is not supported by hw constraints of dormant 16 * mode. While waking up from the dormant mode, a reset signal 17 * to the Cortex-A9 processor must be asserted by the external 18 * power controller. 19 * 20 * With architectural inputs and hardware recommendations, only 21 * below modes are supported from power gain vs latency point of view. 22 * 23 * CPU0 CPU1 MPUSS 24 * ---------------------------------------------- 25 * ON ON ON 26 * ON(Inactive) OFF ON(Inactive) 27 * OFF OFF CSWR 28 * OFF OFF OSWR 29 * OFF OFF OFF(Device OFF *TBD) 30 * ---------------------------------------------- 31 * 32 * Note: CPU0 is the master core and it is the last CPU to go down 33 * and first to wake-up when MPUSS low power states are excercised 34 */ 35 36 #include <linux/kernel.h> 37 #include <linux/io.h> 38 #include <linux/errno.h> 39 #include <linux/linkage.h> 40 #include <linux/smp.h> 41 42 #include <asm/cacheflush.h> 43 #include <asm/tlbflush.h> 44 #include <asm/smp_scu.h> 45 #include <asm/suspend.h> 46 #include <asm/virt.h> 47 #include <asm/hardware/cache-l2x0.h> 48 49 #include "soc.h" 50 #include "common.h" 51 #include "omap44xx.h" 52 #include "omap4-sar-layout.h" 53 #include "pm.h" 54 #include "prcm_mpu44xx.h" 55 #include "prcm_mpu54xx.h" 56 #include "prminst44xx.h" 57 #include "prcm44xx.h" 58 #include "prm44xx.h" 59 #include "prm-regbits-44xx.h" 60 61 static void __iomem *sar_base; 62 static u32 old_cpu1_ns_pa_addr; 63 64 #if defined(CONFIG_PM) && defined(CONFIG_SMP) 65 66 struct omap4_cpu_pm_info { 67 struct powerdomain *pwrdm; 68 void __iomem *scu_sar_addr; 69 void __iomem *wkup_sar_addr; 70 void __iomem *l2x0_sar_addr; 71 }; 72 73 /** 74 * struct cpu_pm_ops - CPU pm operations 75 * @finish_suspend: CPU suspend finisher function pointer 76 * @resume: CPU resume function pointer 77 * @scu_prepare: CPU Snoop Control program function pointer 78 * @hotplug_restart: CPU restart function pointer 79 * 80 * Structure holds functions pointer for CPU low power operations like 81 * suspend, resume and scu programming. 82 */ 83 struct cpu_pm_ops { 84 int (*finish_suspend)(unsigned long cpu_state); 85 void (*resume)(void); 86 void (*scu_prepare)(unsigned int cpu_id, unsigned int cpu_state); 87 void (*hotplug_restart)(void); 88 }; 89 90 static DEFINE_PER_CPU(struct omap4_cpu_pm_info, omap4_pm_info); 91 static struct powerdomain *mpuss_pd; 92 static u32 cpu_context_offset; 93 94 static int default_finish_suspend(unsigned long cpu_state) 95 { 96 omap_do_wfi(); 97 return 0; 98 } 99 100 static void dummy_cpu_resume(void) 101 {} 102 103 static void dummy_scu_prepare(unsigned int cpu_id, unsigned int cpu_state) 104 {} 105 106 static struct cpu_pm_ops omap_pm_ops = { 107 .finish_suspend = default_finish_suspend, 108 .resume = dummy_cpu_resume, 109 .scu_prepare = dummy_scu_prepare, 110 .hotplug_restart = dummy_cpu_resume, 111 }; 112 113 /* 114 * Program the wakeup routine address for the CPU0 and CPU1 115 * used for OFF or DORMANT wakeup. 116 */ 117 static inline void set_cpu_wakeup_addr(unsigned int cpu_id, u32 addr) 118 { 119 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id); 120 121 if (pm_info->wkup_sar_addr) 122 writel_relaxed(addr, pm_info->wkup_sar_addr); 123 } 124 125 /* 126 * Store the SCU power status value to scratchpad memory 127 */ 128 static void scu_pwrst_prepare(unsigned int cpu_id, unsigned int cpu_state) 129 { 130 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id); 131 u32 scu_pwr_st; 132 133 switch (cpu_state) { 134 case PWRDM_POWER_RET: 135 scu_pwr_st = SCU_PM_DORMANT; 136 break; 137 case PWRDM_POWER_OFF: 138 scu_pwr_st = SCU_PM_POWEROFF; 139 break; 140 case PWRDM_POWER_ON: 141 case PWRDM_POWER_INACTIVE: 142 default: 143 scu_pwr_st = SCU_PM_NORMAL; 144 break; 145 } 146 147 if (pm_info->scu_sar_addr) 148 writel_relaxed(scu_pwr_st, pm_info->scu_sar_addr); 149 } 150 151 /* Helper functions for MPUSS OSWR */ 152 static inline void mpuss_clear_prev_logic_pwrst(void) 153 { 154 u32 reg; 155 156 reg = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION, 157 OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET); 158 omap4_prminst_write_inst_reg(reg, OMAP4430_PRM_PARTITION, 159 OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET); 160 } 161 162 static inline void cpu_clear_prev_logic_pwrst(unsigned int cpu_id) 163 { 164 u32 reg; 165 166 if (cpu_id) { 167 reg = omap4_prcm_mpu_read_inst_reg(OMAP4430_PRCM_MPU_CPU1_INST, 168 cpu_context_offset); 169 omap4_prcm_mpu_write_inst_reg(reg, OMAP4430_PRCM_MPU_CPU1_INST, 170 cpu_context_offset); 171 } else { 172 reg = omap4_prcm_mpu_read_inst_reg(OMAP4430_PRCM_MPU_CPU0_INST, 173 cpu_context_offset); 174 omap4_prcm_mpu_write_inst_reg(reg, OMAP4430_PRCM_MPU_CPU0_INST, 175 cpu_context_offset); 176 } 177 } 178 179 /* 180 * Store the CPU cluster state for L2X0 low power operations. 181 */ 182 static void l2x0_pwrst_prepare(unsigned int cpu_id, unsigned int save_state) 183 { 184 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id); 185 186 if (pm_info->l2x0_sar_addr) 187 writel_relaxed(save_state, pm_info->l2x0_sar_addr); 188 } 189 190 /* 191 * Save the L2X0 AUXCTRL and POR value to SAR memory. Its used to 192 * in every restore MPUSS OFF path. 193 */ 194 #ifdef CONFIG_CACHE_L2X0 195 static void __init save_l2x0_context(void) 196 { 197 void __iomem *l2x0_base = omap4_get_l2cache_base(); 198 199 if (l2x0_base && sar_base) { 200 writel_relaxed(l2x0_saved_regs.aux_ctrl, 201 sar_base + L2X0_AUXCTRL_OFFSET); 202 writel_relaxed(l2x0_saved_regs.prefetch_ctrl, 203 sar_base + L2X0_PREFETCH_CTRL_OFFSET); 204 } 205 } 206 #else 207 static void __init save_l2x0_context(void) 208 {} 209 #endif 210 211 /** 212 * omap4_enter_lowpower: OMAP4 MPUSS Low Power Entry Function 213 * The purpose of this function is to manage low power programming 214 * of OMAP4 MPUSS subsystem 215 * @cpu : CPU ID 216 * @power_state: Low power state. 217 * 218 * MPUSS states for the context save: 219 * save_state = 220 * 0 - Nothing lost and no need to save: MPUSS INACTIVE 221 * 1 - CPUx L1 and logic lost: MPUSS CSWR 222 * 2 - CPUx L1 and logic lost + GIC lost: MPUSS OSWR 223 * 3 - CPUx L1 and logic lost + GIC + L2 lost: DEVICE OFF 224 */ 225 int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state) 226 { 227 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu); 228 unsigned int save_state = 0, cpu_logic_state = PWRDM_POWER_RET; 229 230 if (omap_rev() == OMAP4430_REV_ES1_0) 231 return -ENXIO; 232 233 switch (power_state) { 234 case PWRDM_POWER_ON: 235 case PWRDM_POWER_INACTIVE: 236 save_state = 0; 237 break; 238 case PWRDM_POWER_OFF: 239 cpu_logic_state = PWRDM_POWER_OFF; 240 save_state = 1; 241 break; 242 case PWRDM_POWER_RET: 243 if (IS_PM44XX_ERRATUM(PM_OMAP4_CPU_OSWR_DISABLE)) 244 save_state = 0; 245 break; 246 default: 247 /* 248 * CPUx CSWR is invalid hardware state. Also CPUx OSWR 249 * doesn't make much scense, since logic is lost and $L1 250 * needs to be cleaned because of coherency. This makes 251 * CPUx OSWR equivalent to CPUX OFF and hence not supported 252 */ 253 WARN_ON(1); 254 return -ENXIO; 255 } 256 257 pwrdm_pre_transition(NULL); 258 259 /* 260 * Check MPUSS next state and save interrupt controller if needed. 261 * In MPUSS OSWR or device OFF, interrupt controller contest is lost. 262 */ 263 mpuss_clear_prev_logic_pwrst(); 264 if ((pwrdm_read_next_pwrst(mpuss_pd) == PWRDM_POWER_RET) && 265 (pwrdm_read_logic_retst(mpuss_pd) == PWRDM_POWER_OFF)) 266 save_state = 2; 267 268 cpu_clear_prev_logic_pwrst(cpu); 269 pwrdm_set_next_pwrst(pm_info->pwrdm, power_state); 270 pwrdm_set_logic_retst(pm_info->pwrdm, cpu_logic_state); 271 set_cpu_wakeup_addr(cpu, __pa_symbol(omap_pm_ops.resume)); 272 omap_pm_ops.scu_prepare(cpu, power_state); 273 l2x0_pwrst_prepare(cpu, save_state); 274 275 /* 276 * Call low level function with targeted low power state. 277 */ 278 if (save_state) 279 cpu_suspend(save_state, omap_pm_ops.finish_suspend); 280 else 281 omap_pm_ops.finish_suspend(save_state); 282 283 if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD) && cpu) 284 gic_dist_enable(); 285 286 /* 287 * Restore the CPUx power state to ON otherwise CPUx 288 * power domain can transitions to programmed low power 289 * state while doing WFI outside the low powe code. On 290 * secure devices, CPUx does WFI which can result in 291 * domain transition 292 */ 293 pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON); 294 295 pwrdm_post_transition(NULL); 296 297 return 0; 298 } 299 300 /** 301 * omap4_hotplug_cpu: OMAP4 CPU hotplug entry 302 * @cpu : CPU ID 303 * @power_state: CPU low power state. 304 */ 305 int omap4_hotplug_cpu(unsigned int cpu, unsigned int power_state) 306 { 307 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu); 308 unsigned int cpu_state = 0; 309 310 if (omap_rev() == OMAP4430_REV_ES1_0) 311 return -ENXIO; 312 313 /* Use the achievable power state for the domain */ 314 power_state = pwrdm_get_valid_lp_state(pm_info->pwrdm, 315 false, power_state); 316 317 if (power_state == PWRDM_POWER_OFF) 318 cpu_state = 1; 319 320 pwrdm_clear_all_prev_pwrst(pm_info->pwrdm); 321 pwrdm_set_next_pwrst(pm_info->pwrdm, power_state); 322 set_cpu_wakeup_addr(cpu, __pa_symbol(omap_pm_ops.hotplug_restart)); 323 omap_pm_ops.scu_prepare(cpu, power_state); 324 325 /* 326 * CPU never retuns back if targeted power state is OFF mode. 327 * CPU ONLINE follows normal CPU ONLINE ptah via 328 * omap4_secondary_startup(). 329 */ 330 omap_pm_ops.finish_suspend(cpu_state); 331 332 pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON); 333 return 0; 334 } 335 336 337 /* 338 * Enable Mercury Fast HG retention mode by default. 339 */ 340 static void enable_mercury_retention_mode(void) 341 { 342 u32 reg; 343 344 reg = omap4_prcm_mpu_read_inst_reg(OMAP54XX_PRCM_MPU_DEVICE_INST, 345 OMAP54XX_PRCM_MPU_PRM_PSCON_COUNT_OFFSET); 346 /* Enable HG_EN, HG_RAMPUP = fast mode */ 347 reg |= BIT(24) | BIT(25); 348 omap4_prcm_mpu_write_inst_reg(reg, OMAP54XX_PRCM_MPU_DEVICE_INST, 349 OMAP54XX_PRCM_MPU_PRM_PSCON_COUNT_OFFSET); 350 } 351 352 /* 353 * Initialise OMAP4 MPUSS 354 */ 355 int __init omap4_mpuss_init(void) 356 { 357 struct omap4_cpu_pm_info *pm_info; 358 359 if (omap_rev() == OMAP4430_REV_ES1_0) { 360 WARN(1, "Power Management not supported on OMAP4430 ES1.0\n"); 361 return -ENODEV; 362 } 363 364 /* Initilaise per CPU PM information */ 365 pm_info = &per_cpu(omap4_pm_info, 0x0); 366 if (sar_base) { 367 pm_info->scu_sar_addr = sar_base + SCU_OFFSET0; 368 if (cpu_is_omap44xx()) 369 pm_info->wkup_sar_addr = sar_base + 370 CPU0_WAKEUP_NS_PA_ADDR_OFFSET; 371 else 372 pm_info->wkup_sar_addr = sar_base + 373 OMAP5_CPU0_WAKEUP_NS_PA_ADDR_OFFSET; 374 pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET0; 375 } 376 pm_info->pwrdm = pwrdm_lookup("cpu0_pwrdm"); 377 if (!pm_info->pwrdm) { 378 pr_err("Lookup failed for CPU0 pwrdm\n"); 379 return -ENODEV; 380 } 381 382 /* Clear CPU previous power domain state */ 383 pwrdm_clear_all_prev_pwrst(pm_info->pwrdm); 384 cpu_clear_prev_logic_pwrst(0); 385 386 /* Initialise CPU0 power domain state to ON */ 387 pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON); 388 389 pm_info = &per_cpu(omap4_pm_info, 0x1); 390 if (sar_base) { 391 pm_info->scu_sar_addr = sar_base + SCU_OFFSET1; 392 if (cpu_is_omap44xx()) 393 pm_info->wkup_sar_addr = sar_base + 394 CPU1_WAKEUP_NS_PA_ADDR_OFFSET; 395 else 396 pm_info->wkup_sar_addr = sar_base + 397 OMAP5_CPU1_WAKEUP_NS_PA_ADDR_OFFSET; 398 pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET1; 399 } 400 401 pm_info->pwrdm = pwrdm_lookup("cpu1_pwrdm"); 402 if (!pm_info->pwrdm) { 403 pr_err("Lookup failed for CPU1 pwrdm\n"); 404 return -ENODEV; 405 } 406 407 /* Clear CPU previous power domain state */ 408 pwrdm_clear_all_prev_pwrst(pm_info->pwrdm); 409 cpu_clear_prev_logic_pwrst(1); 410 411 /* Initialise CPU1 power domain state to ON */ 412 pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON); 413 414 mpuss_pd = pwrdm_lookup("mpu_pwrdm"); 415 if (!mpuss_pd) { 416 pr_err("Failed to lookup MPUSS power domain\n"); 417 return -ENODEV; 418 } 419 pwrdm_clear_all_prev_pwrst(mpuss_pd); 420 mpuss_clear_prev_logic_pwrst(); 421 422 if (sar_base) { 423 /* Save device type on scratchpad for low level code to use */ 424 writel_relaxed((omap_type() != OMAP2_DEVICE_TYPE_GP) ? 1 : 0, 425 sar_base + OMAP_TYPE_OFFSET); 426 save_l2x0_context(); 427 } 428 429 if (cpu_is_omap44xx()) { 430 omap_pm_ops.finish_suspend = omap4_finish_suspend; 431 omap_pm_ops.resume = omap4_cpu_resume; 432 omap_pm_ops.scu_prepare = scu_pwrst_prepare; 433 omap_pm_ops.hotplug_restart = omap4_secondary_startup; 434 cpu_context_offset = OMAP4_RM_CPU0_CPU0_CONTEXT_OFFSET; 435 } else if (soc_is_omap54xx() || soc_is_dra7xx()) { 436 cpu_context_offset = OMAP54XX_RM_CPU0_CPU0_CONTEXT_OFFSET; 437 enable_mercury_retention_mode(); 438 } 439 440 if (cpu_is_omap446x()) 441 omap_pm_ops.hotplug_restart = omap4460_secondary_startup; 442 443 return 0; 444 } 445 446 #endif 447 448 u32 omap4_get_cpu1_ns_pa_addr(void) 449 { 450 return old_cpu1_ns_pa_addr; 451 } 452 453 /* 454 * For kexec, we must set CPU1_WAKEUP_NS_PA_ADDR to point to 455 * current kernel's secondary_startup() early before 456 * clockdomains_init(). Otherwise clockdomain_init() can 457 * wake CPU1 and cause a hang. 458 */ 459 void __init omap4_mpuss_early_init(void) 460 { 461 unsigned long startup_pa; 462 void __iomem *ns_pa_addr; 463 464 if (!(soc_is_omap44xx() || soc_is_omap54xx())) 465 return; 466 467 sar_base = omap4_get_sar_ram_base(); 468 469 /* Save old NS_PA_ADDR for validity checks later on */ 470 if (soc_is_omap44xx()) 471 ns_pa_addr = sar_base + CPU1_WAKEUP_NS_PA_ADDR_OFFSET; 472 else 473 ns_pa_addr = sar_base + OMAP5_CPU1_WAKEUP_NS_PA_ADDR_OFFSET; 474 old_cpu1_ns_pa_addr = readl_relaxed(ns_pa_addr); 475 476 if (soc_is_omap443x()) 477 startup_pa = __pa_symbol(omap4_secondary_startup); 478 else if (soc_is_omap446x()) 479 startup_pa = __pa_symbol(omap4460_secondary_startup); 480 else if ((__boot_cpu_mode & MODE_MASK) == HYP_MODE) 481 startup_pa = __pa_symbol(omap5_secondary_hyp_startup); 482 else 483 startup_pa = __pa_symbol(omap5_secondary_startup); 484 485 if (soc_is_omap44xx()) 486 writel_relaxed(startup_pa, sar_base + 487 CPU1_WAKEUP_NS_PA_ADDR_OFFSET); 488 else 489 writel_relaxed(startup_pa, sar_base + 490 OMAP5_CPU1_WAKEUP_NS_PA_ADDR_OFFSET); 491 } 492