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/pgalloc.h> 46 #include <asm/suspend.h> 47 #include <asm/virt.h> 48 #include <asm/hardware/cache-l2x0.h> 49 50 #include "soc.h" 51 #include "common.h" 52 #include "omap44xx.h" 53 #include "omap4-sar-layout.h" 54 #include "pm.h" 55 #include "prcm_mpu44xx.h" 56 #include "prcm_mpu54xx.h" 57 #include "prminst44xx.h" 58 #include "prcm44xx.h" 59 #include "prm44xx.h" 60 #include "prm-regbits-44xx.h" 61 62 static void __iomem *sar_base; 63 static u32 old_cpu1_ns_pa_addr; 64 65 #if defined(CONFIG_PM) && defined(CONFIG_SMP) 66 67 struct omap4_cpu_pm_info { 68 struct powerdomain *pwrdm; 69 void __iomem *scu_sar_addr; 70 void __iomem *wkup_sar_addr; 71 void __iomem *l2x0_sar_addr; 72 }; 73 74 /** 75 * struct cpu_pm_ops - CPU pm operations 76 * @finish_suspend: CPU suspend finisher function pointer 77 * @resume: CPU resume function pointer 78 * @scu_prepare: CPU Snoop Control program function pointer 79 * @hotplug_restart: CPU restart function pointer 80 * 81 * Structure holds functions pointer for CPU low power operations like 82 * suspend, resume and scu programming. 83 */ 84 struct cpu_pm_ops { 85 int (*finish_suspend)(unsigned long cpu_state); 86 void (*resume)(void); 87 void (*scu_prepare)(unsigned int cpu_id, unsigned int cpu_state); 88 void (*hotplug_restart)(void); 89 }; 90 91 static DEFINE_PER_CPU(struct omap4_cpu_pm_info, omap4_pm_info); 92 static struct powerdomain *mpuss_pd; 93 static u32 cpu_context_offset; 94 95 static int default_finish_suspend(unsigned long cpu_state) 96 { 97 omap_do_wfi(); 98 return 0; 99 } 100 101 static void dummy_cpu_resume(void) 102 {} 103 104 static void dummy_scu_prepare(unsigned int cpu_id, unsigned int cpu_state) 105 {} 106 107 static struct cpu_pm_ops omap_pm_ops = { 108 .finish_suspend = default_finish_suspend, 109 .resume = dummy_cpu_resume, 110 .scu_prepare = dummy_scu_prepare, 111 .hotplug_restart = dummy_cpu_resume, 112 }; 113 114 /* 115 * Program the wakeup routine address for the CPU0 and CPU1 116 * used for OFF or DORMANT wakeup. 117 */ 118 static inline void set_cpu_wakeup_addr(unsigned int cpu_id, u32 addr) 119 { 120 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id); 121 122 if (pm_info->wkup_sar_addr) 123 writel_relaxed(addr, pm_info->wkup_sar_addr); 124 } 125 126 /* 127 * Store the SCU power status value to scratchpad memory 128 */ 129 static void scu_pwrst_prepare(unsigned int cpu_id, unsigned int cpu_state) 130 { 131 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id); 132 u32 scu_pwr_st; 133 134 switch (cpu_state) { 135 case PWRDM_POWER_RET: 136 scu_pwr_st = SCU_PM_DORMANT; 137 break; 138 case PWRDM_POWER_OFF: 139 scu_pwr_st = SCU_PM_POWEROFF; 140 break; 141 case PWRDM_POWER_ON: 142 case PWRDM_POWER_INACTIVE: 143 default: 144 scu_pwr_st = SCU_PM_NORMAL; 145 break; 146 } 147 148 if (pm_info->scu_sar_addr) 149 writel_relaxed(scu_pwr_st, pm_info->scu_sar_addr); 150 } 151 152 /* Helper functions for MPUSS OSWR */ 153 static inline void mpuss_clear_prev_logic_pwrst(void) 154 { 155 u32 reg; 156 157 reg = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION, 158 OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET); 159 omap4_prminst_write_inst_reg(reg, OMAP4430_PRM_PARTITION, 160 OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET); 161 } 162 163 static inline void cpu_clear_prev_logic_pwrst(unsigned int cpu_id) 164 { 165 u32 reg; 166 167 if (cpu_id) { 168 reg = omap4_prcm_mpu_read_inst_reg(OMAP4430_PRCM_MPU_CPU1_INST, 169 cpu_context_offset); 170 omap4_prcm_mpu_write_inst_reg(reg, OMAP4430_PRCM_MPU_CPU1_INST, 171 cpu_context_offset); 172 } else { 173 reg = omap4_prcm_mpu_read_inst_reg(OMAP4430_PRCM_MPU_CPU0_INST, 174 cpu_context_offset); 175 omap4_prcm_mpu_write_inst_reg(reg, OMAP4430_PRCM_MPU_CPU0_INST, 176 cpu_context_offset); 177 } 178 } 179 180 /* 181 * Store the CPU cluster state for L2X0 low power operations. 182 */ 183 static void l2x0_pwrst_prepare(unsigned int cpu_id, unsigned int save_state) 184 { 185 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id); 186 187 if (pm_info->l2x0_sar_addr) 188 writel_relaxed(save_state, pm_info->l2x0_sar_addr); 189 } 190 191 /* 192 * Save the L2X0 AUXCTRL and POR value to SAR memory. Its used to 193 * in every restore MPUSS OFF path. 194 */ 195 #ifdef CONFIG_CACHE_L2X0 196 static void __init save_l2x0_context(void) 197 { 198 void __iomem *l2x0_base = omap4_get_l2cache_base(); 199 200 if (l2x0_base && sar_base) { 201 writel_relaxed(l2x0_saved_regs.aux_ctrl, 202 sar_base + L2X0_AUXCTRL_OFFSET); 203 writel_relaxed(l2x0_saved_regs.prefetch_ctrl, 204 sar_base + L2X0_PREFETCH_CTRL_OFFSET); 205 } 206 } 207 #else 208 static void __init save_l2x0_context(void) 209 {} 210 #endif 211 212 /** 213 * omap4_enter_lowpower: OMAP4 MPUSS Low Power Entry Function 214 * The purpose of this function is to manage low power programming 215 * of OMAP4 MPUSS subsystem 216 * @cpu : CPU ID 217 * @power_state: Low power state. 218 * 219 * MPUSS states for the context save: 220 * save_state = 221 * 0 - Nothing lost and no need to save: MPUSS INACTIVE 222 * 1 - CPUx L1 and logic lost: MPUSS CSWR 223 * 2 - CPUx L1 and logic lost + GIC lost: MPUSS OSWR 224 * 3 - CPUx L1 and logic lost + GIC + L2 lost: DEVICE OFF 225 */ 226 int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state) 227 { 228 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu); 229 unsigned int save_state = 0, cpu_logic_state = PWRDM_POWER_RET; 230 231 if (omap_rev() == OMAP4430_REV_ES1_0) 232 return -ENXIO; 233 234 switch (power_state) { 235 case PWRDM_POWER_ON: 236 case PWRDM_POWER_INACTIVE: 237 save_state = 0; 238 break; 239 case PWRDM_POWER_OFF: 240 cpu_logic_state = PWRDM_POWER_OFF; 241 save_state = 1; 242 break; 243 case PWRDM_POWER_RET: 244 if (IS_PM44XX_ERRATUM(PM_OMAP4_CPU_OSWR_DISABLE)) 245 save_state = 0; 246 break; 247 default: 248 /* 249 * CPUx CSWR is invalid hardware state. Also CPUx OSWR 250 * doesn't make much scense, since logic is lost and $L1 251 * needs to be cleaned because of coherency. This makes 252 * CPUx OSWR equivalent to CPUX OFF and hence not supported 253 */ 254 WARN_ON(1); 255 return -ENXIO; 256 } 257 258 pwrdm_pre_transition(NULL); 259 260 /* 261 * Check MPUSS next state and save interrupt controller if needed. 262 * In MPUSS OSWR or device OFF, interrupt controller contest is lost. 263 */ 264 mpuss_clear_prev_logic_pwrst(); 265 if ((pwrdm_read_next_pwrst(mpuss_pd) == PWRDM_POWER_RET) && 266 (pwrdm_read_logic_retst(mpuss_pd) == PWRDM_POWER_OFF)) 267 save_state = 2; 268 269 cpu_clear_prev_logic_pwrst(cpu); 270 pwrdm_set_next_pwrst(pm_info->pwrdm, power_state); 271 pwrdm_set_logic_retst(pm_info->pwrdm, cpu_logic_state); 272 set_cpu_wakeup_addr(cpu, __pa_symbol(omap_pm_ops.resume)); 273 omap_pm_ops.scu_prepare(cpu, power_state); 274 l2x0_pwrst_prepare(cpu, save_state); 275 276 /* 277 * Call low level function with targeted low power state. 278 */ 279 if (save_state) 280 cpu_suspend(save_state, omap_pm_ops.finish_suspend); 281 else 282 omap_pm_ops.finish_suspend(save_state); 283 284 if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD) && cpu) 285 gic_dist_enable(); 286 287 /* 288 * Restore the CPUx power state to ON otherwise CPUx 289 * power domain can transitions to programmed low power 290 * state while doing WFI outside the low powe code. On 291 * secure devices, CPUx does WFI which can result in 292 * domain transition 293 */ 294 pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON); 295 296 pwrdm_post_transition(NULL); 297 298 return 0; 299 } 300 301 /** 302 * omap4_hotplug_cpu: OMAP4 CPU hotplug entry 303 * @cpu : CPU ID 304 * @power_state: CPU low power state. 305 */ 306 int omap4_hotplug_cpu(unsigned int cpu, unsigned int power_state) 307 { 308 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu); 309 unsigned int cpu_state = 0; 310 311 if (omap_rev() == OMAP4430_REV_ES1_0) 312 return -ENXIO; 313 314 /* Use the achievable power state for the domain */ 315 power_state = pwrdm_get_valid_lp_state(pm_info->pwrdm, 316 false, power_state); 317 318 if (power_state == PWRDM_POWER_OFF) 319 cpu_state = 1; 320 321 pwrdm_clear_all_prev_pwrst(pm_info->pwrdm); 322 pwrdm_set_next_pwrst(pm_info->pwrdm, power_state); 323 set_cpu_wakeup_addr(cpu, __pa_symbol(omap_pm_ops.hotplug_restart)); 324 omap_pm_ops.scu_prepare(cpu, power_state); 325 326 /* 327 * CPU never retuns back if targeted power state is OFF mode. 328 * CPU ONLINE follows normal CPU ONLINE ptah via 329 * omap4_secondary_startup(). 330 */ 331 omap_pm_ops.finish_suspend(cpu_state); 332 333 pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON); 334 return 0; 335 } 336 337 338 /* 339 * Enable Mercury Fast HG retention mode by default. 340 */ 341 static void enable_mercury_retention_mode(void) 342 { 343 u32 reg; 344 345 reg = omap4_prcm_mpu_read_inst_reg(OMAP54XX_PRCM_MPU_DEVICE_INST, 346 OMAP54XX_PRCM_MPU_PRM_PSCON_COUNT_OFFSET); 347 /* Enable HG_EN, HG_RAMPUP = fast mode */ 348 reg |= BIT(24) | BIT(25); 349 omap4_prcm_mpu_write_inst_reg(reg, OMAP54XX_PRCM_MPU_DEVICE_INST, 350 OMAP54XX_PRCM_MPU_PRM_PSCON_COUNT_OFFSET); 351 } 352 353 /* 354 * Initialise OMAP4 MPUSS 355 */ 356 int __init omap4_mpuss_init(void) 357 { 358 struct omap4_cpu_pm_info *pm_info; 359 360 if (omap_rev() == OMAP4430_REV_ES1_0) { 361 WARN(1, "Power Management not supported on OMAP4430 ES1.0\n"); 362 return -ENODEV; 363 } 364 365 /* Initilaise per CPU PM information */ 366 pm_info = &per_cpu(omap4_pm_info, 0x0); 367 if (sar_base) { 368 pm_info->scu_sar_addr = sar_base + SCU_OFFSET0; 369 if (cpu_is_omap44xx()) 370 pm_info->wkup_sar_addr = sar_base + 371 CPU0_WAKEUP_NS_PA_ADDR_OFFSET; 372 else 373 pm_info->wkup_sar_addr = sar_base + 374 OMAP5_CPU0_WAKEUP_NS_PA_ADDR_OFFSET; 375 pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET0; 376 } 377 pm_info->pwrdm = pwrdm_lookup("cpu0_pwrdm"); 378 if (!pm_info->pwrdm) { 379 pr_err("Lookup failed for CPU0 pwrdm\n"); 380 return -ENODEV; 381 } 382 383 /* Clear CPU previous power domain state */ 384 pwrdm_clear_all_prev_pwrst(pm_info->pwrdm); 385 cpu_clear_prev_logic_pwrst(0); 386 387 /* Initialise CPU0 power domain state to ON */ 388 pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON); 389 390 pm_info = &per_cpu(omap4_pm_info, 0x1); 391 if (sar_base) { 392 pm_info->scu_sar_addr = sar_base + SCU_OFFSET1; 393 if (cpu_is_omap44xx()) 394 pm_info->wkup_sar_addr = sar_base + 395 CPU1_WAKEUP_NS_PA_ADDR_OFFSET; 396 else 397 pm_info->wkup_sar_addr = sar_base + 398 OMAP5_CPU1_WAKEUP_NS_PA_ADDR_OFFSET; 399 pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET1; 400 } 401 402 pm_info->pwrdm = pwrdm_lookup("cpu1_pwrdm"); 403 if (!pm_info->pwrdm) { 404 pr_err("Lookup failed for CPU1 pwrdm\n"); 405 return -ENODEV; 406 } 407 408 /* Clear CPU previous power domain state */ 409 pwrdm_clear_all_prev_pwrst(pm_info->pwrdm); 410 cpu_clear_prev_logic_pwrst(1); 411 412 /* Initialise CPU1 power domain state to ON */ 413 pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON); 414 415 mpuss_pd = pwrdm_lookup("mpu_pwrdm"); 416 if (!mpuss_pd) { 417 pr_err("Failed to lookup MPUSS power domain\n"); 418 return -ENODEV; 419 } 420 pwrdm_clear_all_prev_pwrst(mpuss_pd); 421 mpuss_clear_prev_logic_pwrst(); 422 423 if (sar_base) { 424 /* Save device type on scratchpad for low level code to use */ 425 writel_relaxed((omap_type() != OMAP2_DEVICE_TYPE_GP) ? 1 : 0, 426 sar_base + OMAP_TYPE_OFFSET); 427 save_l2x0_context(); 428 } 429 430 if (cpu_is_omap44xx()) { 431 omap_pm_ops.finish_suspend = omap4_finish_suspend; 432 omap_pm_ops.resume = omap4_cpu_resume; 433 omap_pm_ops.scu_prepare = scu_pwrst_prepare; 434 omap_pm_ops.hotplug_restart = omap4_secondary_startup; 435 cpu_context_offset = OMAP4_RM_CPU0_CPU0_CONTEXT_OFFSET; 436 } else if (soc_is_omap54xx() || soc_is_dra7xx()) { 437 cpu_context_offset = OMAP54XX_RM_CPU0_CPU0_CONTEXT_OFFSET; 438 enable_mercury_retention_mode(); 439 } 440 441 if (cpu_is_omap446x()) 442 omap_pm_ops.hotplug_restart = omap4460_secondary_startup; 443 444 return 0; 445 } 446 447 #endif 448 449 u32 omap4_get_cpu1_ns_pa_addr(void) 450 { 451 return old_cpu1_ns_pa_addr; 452 } 453 454 /* 455 * For kexec, we must set CPU1_WAKEUP_NS_PA_ADDR to point to 456 * current kernel's secondary_startup() early before 457 * clockdomains_init(). Otherwise clockdomain_init() can 458 * wake CPU1 and cause a hang. 459 */ 460 void __init omap4_mpuss_early_init(void) 461 { 462 unsigned long startup_pa; 463 void __iomem *ns_pa_addr; 464 465 if (!(soc_is_omap44xx() || soc_is_omap54xx())) 466 return; 467 468 sar_base = omap4_get_sar_ram_base(); 469 470 /* Save old NS_PA_ADDR for validity checks later on */ 471 if (soc_is_omap44xx()) 472 ns_pa_addr = sar_base + CPU1_WAKEUP_NS_PA_ADDR_OFFSET; 473 else 474 ns_pa_addr = sar_base + OMAP5_CPU1_WAKEUP_NS_PA_ADDR_OFFSET; 475 old_cpu1_ns_pa_addr = readl_relaxed(ns_pa_addr); 476 477 if (soc_is_omap443x()) 478 startup_pa = __pa_symbol(omap4_secondary_startup); 479 else if (soc_is_omap446x()) 480 startup_pa = __pa_symbol(omap4460_secondary_startup); 481 else if ((__boot_cpu_mode & MODE_MASK) == HYP_MODE) 482 startup_pa = __pa_symbol(omap5_secondary_hyp_startup); 483 else 484 startup_pa = __pa_symbol(omap5_secondary_startup); 485 486 if (soc_is_omap44xx()) 487 writel_relaxed(startup_pa, sar_base + 488 CPU1_WAKEUP_NS_PA_ADDR_OFFSET); 489 else 490 writel_relaxed(startup_pa, sar_base + 491 OMAP5_CPU1_WAKEUP_NS_PA_ADDR_OFFSET); 492 } 493