1 /* 2 * OMAP WakeupGen Source file 3 * 4 * OMAP WakeupGen is the interrupt controller extension used along 5 * with ARM GIC to wake the CPU out from low power states on 6 * external interrupts. It is responsible for generating wakeup 7 * event from the incoming interrupts and enable bits. It is 8 * implemented in MPU always ON power domain. During normal operation, 9 * WakeupGen delivers external interrupts directly to the GIC. 10 * 11 * Copyright (C) 2011 Texas Instruments, Inc. 12 * Santosh Shilimkar <santosh.shilimkar@ti.com> 13 * 14 * This program is free software; you can redistribute it and/or modify 15 * it under the terms of the GNU General Public License version 2 as 16 * published by the Free Software Foundation. 17 */ 18 19 #include <linux/kernel.h> 20 #include <linux/init.h> 21 #include <linux/io.h> 22 #include <linux/irq.h> 23 #include <linux/irqchip.h> 24 #include <linux/irqdomain.h> 25 #include <linux/of_address.h> 26 #include <linux/platform_device.h> 27 #include <linux/cpu.h> 28 #include <linux/notifier.h> 29 #include <linux/cpu_pm.h> 30 31 #include "omap-wakeupgen.h" 32 #include "omap-secure.h" 33 34 #include "soc.h" 35 #include "omap4-sar-layout.h" 36 #include "common.h" 37 #include "pm.h" 38 39 #define AM43XX_NR_REG_BANKS 7 40 #define AM43XX_IRQS 224 41 #define MAX_NR_REG_BANKS AM43XX_NR_REG_BANKS 42 #define MAX_IRQS AM43XX_IRQS 43 #define DEFAULT_NR_REG_BANKS 5 44 #define DEFAULT_IRQS 160 45 #define WKG_MASK_ALL 0x00000000 46 #define WKG_UNMASK_ALL 0xffffffff 47 #define CPU_ENA_OFFSET 0x400 48 #define CPU0_ID 0x0 49 #define CPU1_ID 0x1 50 #define OMAP4_NR_BANKS 4 51 #define OMAP4_NR_IRQS 128 52 53 static void __iomem *wakeupgen_base; 54 static void __iomem *sar_base; 55 static DEFINE_RAW_SPINLOCK(wakeupgen_lock); 56 static unsigned int irq_target_cpu[MAX_IRQS]; 57 static unsigned int irq_banks = DEFAULT_NR_REG_BANKS; 58 static unsigned int max_irqs = DEFAULT_IRQS; 59 static unsigned int omap_secure_apis; 60 61 /* 62 * Static helper functions. 63 */ 64 static inline u32 wakeupgen_readl(u8 idx, u32 cpu) 65 { 66 return readl_relaxed(wakeupgen_base + OMAP_WKG_ENB_A_0 + 67 (cpu * CPU_ENA_OFFSET) + (idx * 4)); 68 } 69 70 static inline void wakeupgen_writel(u32 val, u8 idx, u32 cpu) 71 { 72 writel_relaxed(val, wakeupgen_base + OMAP_WKG_ENB_A_0 + 73 (cpu * CPU_ENA_OFFSET) + (idx * 4)); 74 } 75 76 static inline void sar_writel(u32 val, u32 offset, u8 idx) 77 { 78 writel_relaxed(val, sar_base + offset + (idx * 4)); 79 } 80 81 static inline int _wakeupgen_get_irq_info(u32 irq, u32 *bit_posn, u8 *reg_index) 82 { 83 /* 84 * Each WakeupGen register controls 32 interrupt. 85 * i.e. 1 bit per SPI IRQ 86 */ 87 *reg_index = irq >> 5; 88 *bit_posn = irq %= 32; 89 90 return 0; 91 } 92 93 static void _wakeupgen_clear(unsigned int irq, unsigned int cpu) 94 { 95 u32 val, bit_number; 96 u8 i; 97 98 if (_wakeupgen_get_irq_info(irq, &bit_number, &i)) 99 return; 100 101 val = wakeupgen_readl(i, cpu); 102 val &= ~BIT(bit_number); 103 wakeupgen_writel(val, i, cpu); 104 } 105 106 static void _wakeupgen_set(unsigned int irq, unsigned int cpu) 107 { 108 u32 val, bit_number; 109 u8 i; 110 111 if (_wakeupgen_get_irq_info(irq, &bit_number, &i)) 112 return; 113 114 val = wakeupgen_readl(i, cpu); 115 val |= BIT(bit_number); 116 wakeupgen_writel(val, i, cpu); 117 } 118 119 /* 120 * Architecture specific Mask extension 121 */ 122 static void wakeupgen_mask(struct irq_data *d) 123 { 124 unsigned long flags; 125 126 raw_spin_lock_irqsave(&wakeupgen_lock, flags); 127 _wakeupgen_clear(d->hwirq, irq_target_cpu[d->hwirq]); 128 raw_spin_unlock_irqrestore(&wakeupgen_lock, flags); 129 irq_chip_mask_parent(d); 130 } 131 132 /* 133 * Architecture specific Unmask extension 134 */ 135 static void wakeupgen_unmask(struct irq_data *d) 136 { 137 unsigned long flags; 138 139 raw_spin_lock_irqsave(&wakeupgen_lock, flags); 140 _wakeupgen_set(d->hwirq, irq_target_cpu[d->hwirq]); 141 raw_spin_unlock_irqrestore(&wakeupgen_lock, flags); 142 irq_chip_unmask_parent(d); 143 } 144 145 #ifdef CONFIG_HOTPLUG_CPU 146 static DEFINE_PER_CPU(u32 [MAX_NR_REG_BANKS], irqmasks); 147 148 static void _wakeupgen_save_masks(unsigned int cpu) 149 { 150 u8 i; 151 152 for (i = 0; i < irq_banks; i++) 153 per_cpu(irqmasks, cpu)[i] = wakeupgen_readl(i, cpu); 154 } 155 156 static void _wakeupgen_restore_masks(unsigned int cpu) 157 { 158 u8 i; 159 160 for (i = 0; i < irq_banks; i++) 161 wakeupgen_writel(per_cpu(irqmasks, cpu)[i], i, cpu); 162 } 163 164 static void _wakeupgen_set_all(unsigned int cpu, unsigned int reg) 165 { 166 u8 i; 167 168 for (i = 0; i < irq_banks; i++) 169 wakeupgen_writel(reg, i, cpu); 170 } 171 172 /* 173 * Mask or unmask all interrupts on given CPU. 174 * 0 = Mask all interrupts on the 'cpu' 175 * 1 = Unmask all interrupts on the 'cpu' 176 * Ensure that the initial mask is maintained. This is faster than 177 * iterating through GIC registers to arrive at the correct masks. 178 */ 179 static void wakeupgen_irqmask_all(unsigned int cpu, unsigned int set) 180 { 181 unsigned long flags; 182 183 raw_spin_lock_irqsave(&wakeupgen_lock, flags); 184 if (set) { 185 _wakeupgen_save_masks(cpu); 186 _wakeupgen_set_all(cpu, WKG_MASK_ALL); 187 } else { 188 _wakeupgen_set_all(cpu, WKG_UNMASK_ALL); 189 _wakeupgen_restore_masks(cpu); 190 } 191 raw_spin_unlock_irqrestore(&wakeupgen_lock, flags); 192 } 193 #endif 194 195 #ifdef CONFIG_CPU_PM 196 static inline void omap4_irq_save_context(void) 197 { 198 u32 i, val; 199 200 if (omap_rev() == OMAP4430_REV_ES1_0) 201 return; 202 203 for (i = 0; i < irq_banks; i++) { 204 /* Save the CPUx interrupt mask for IRQ 0 to 127 */ 205 val = wakeupgen_readl(i, 0); 206 sar_writel(val, WAKEUPGENENB_OFFSET_CPU0, i); 207 val = wakeupgen_readl(i, 1); 208 sar_writel(val, WAKEUPGENENB_OFFSET_CPU1, i); 209 210 /* 211 * Disable the secure interrupts for CPUx. The restore 212 * code blindly restores secure and non-secure interrupt 213 * masks from SAR RAM. Secure interrupts are not suppose 214 * to be enabled from HLOS. So overwrite the SAR location 215 * so that the secure interrupt remains disabled. 216 */ 217 sar_writel(0x0, WAKEUPGENENB_SECURE_OFFSET_CPU0, i); 218 sar_writel(0x0, WAKEUPGENENB_SECURE_OFFSET_CPU1, i); 219 } 220 221 /* Save AuxBoot* registers */ 222 val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_0); 223 writel_relaxed(val, sar_base + AUXCOREBOOT0_OFFSET); 224 val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_1); 225 writel_relaxed(val, sar_base + AUXCOREBOOT1_OFFSET); 226 227 /* Save SyncReq generation logic */ 228 val = readl_relaxed(wakeupgen_base + OMAP_PTMSYNCREQ_MASK); 229 writel_relaxed(val, sar_base + PTMSYNCREQ_MASK_OFFSET); 230 val = readl_relaxed(wakeupgen_base + OMAP_PTMSYNCREQ_EN); 231 writel_relaxed(val, sar_base + PTMSYNCREQ_EN_OFFSET); 232 233 /* Set the Backup Bit Mask status */ 234 val = readl_relaxed(sar_base + SAR_BACKUP_STATUS_OFFSET); 235 val |= SAR_BACKUP_STATUS_WAKEUPGEN; 236 writel_relaxed(val, sar_base + SAR_BACKUP_STATUS_OFFSET); 237 238 } 239 240 static inline void omap5_irq_save_context(void) 241 { 242 u32 i, val; 243 244 for (i = 0; i < irq_banks; i++) { 245 /* Save the CPUx interrupt mask for IRQ 0 to 159 */ 246 val = wakeupgen_readl(i, 0); 247 sar_writel(val, OMAP5_WAKEUPGENENB_OFFSET_CPU0, i); 248 val = wakeupgen_readl(i, 1); 249 sar_writel(val, OMAP5_WAKEUPGENENB_OFFSET_CPU1, i); 250 sar_writel(0x0, OMAP5_WAKEUPGENENB_SECURE_OFFSET_CPU0, i); 251 sar_writel(0x0, OMAP5_WAKEUPGENENB_SECURE_OFFSET_CPU1, i); 252 } 253 254 /* Save AuxBoot* registers */ 255 val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_0); 256 writel_relaxed(val, sar_base + OMAP5_AUXCOREBOOT0_OFFSET); 257 val = readl_relaxed(wakeupgen_base + OMAP_AUX_CORE_BOOT_0); 258 writel_relaxed(val, sar_base + OMAP5_AUXCOREBOOT1_OFFSET); 259 260 /* Set the Backup Bit Mask status */ 261 val = readl_relaxed(sar_base + OMAP5_SAR_BACKUP_STATUS_OFFSET); 262 val |= SAR_BACKUP_STATUS_WAKEUPGEN; 263 writel_relaxed(val, sar_base + OMAP5_SAR_BACKUP_STATUS_OFFSET); 264 265 } 266 267 /* 268 * Save WakeupGen interrupt context in SAR BANK3. Restore is done by 269 * ROM code. WakeupGen IP is integrated along with GIC to manage the 270 * interrupt wakeups from CPU low power states. It manages 271 * masking/unmasking of Shared peripheral interrupts(SPI). So the 272 * interrupt enable/disable control should be in sync and consistent 273 * at WakeupGen and GIC so that interrupts are not lost. 274 */ 275 static void irq_save_context(void) 276 { 277 if (!sar_base) 278 sar_base = omap4_get_sar_ram_base(); 279 280 if (soc_is_omap54xx()) 281 omap5_irq_save_context(); 282 else 283 omap4_irq_save_context(); 284 } 285 286 /* 287 * Clear WakeupGen SAR backup status. 288 */ 289 static void irq_sar_clear(void) 290 { 291 u32 val; 292 u32 offset = SAR_BACKUP_STATUS_OFFSET; 293 294 if (soc_is_omap54xx()) 295 offset = OMAP5_SAR_BACKUP_STATUS_OFFSET; 296 297 val = readl_relaxed(sar_base + offset); 298 val &= ~SAR_BACKUP_STATUS_WAKEUPGEN; 299 writel_relaxed(val, sar_base + offset); 300 } 301 302 /* 303 * Save GIC and Wakeupgen interrupt context using secure API 304 * for HS/EMU devices. 305 */ 306 static void irq_save_secure_context(void) 307 { 308 u32 ret; 309 ret = omap_secure_dispatcher(OMAP4_HAL_SAVEGIC_INDEX, 310 FLAG_START_CRITICAL, 311 0, 0, 0, 0, 0); 312 if (ret != API_HAL_RET_VALUE_OK) 313 pr_err("GIC and Wakeupgen context save failed\n"); 314 } 315 #endif 316 317 #ifdef CONFIG_HOTPLUG_CPU 318 static int irq_cpu_hotplug_notify(struct notifier_block *self, 319 unsigned long action, void *hcpu) 320 { 321 unsigned int cpu = (unsigned int)hcpu; 322 323 switch (action) { 324 case CPU_ONLINE: 325 wakeupgen_irqmask_all(cpu, 0); 326 break; 327 case CPU_DEAD: 328 wakeupgen_irqmask_all(cpu, 1); 329 break; 330 } 331 return NOTIFY_OK; 332 } 333 334 static struct notifier_block irq_hotplug_notifier = { 335 .notifier_call = irq_cpu_hotplug_notify, 336 }; 337 338 static void __init irq_hotplug_init(void) 339 { 340 register_hotcpu_notifier(&irq_hotplug_notifier); 341 } 342 #else 343 static void __init irq_hotplug_init(void) 344 {} 345 #endif 346 347 #ifdef CONFIG_CPU_PM 348 static int irq_notifier(struct notifier_block *self, unsigned long cmd, void *v) 349 { 350 switch (cmd) { 351 case CPU_CLUSTER_PM_ENTER: 352 if (omap_type() == OMAP2_DEVICE_TYPE_GP) 353 irq_save_context(); 354 else 355 irq_save_secure_context(); 356 break; 357 case CPU_CLUSTER_PM_EXIT: 358 if (omap_type() == OMAP2_DEVICE_TYPE_GP) 359 irq_sar_clear(); 360 break; 361 } 362 return NOTIFY_OK; 363 } 364 365 static struct notifier_block irq_notifier_block = { 366 .notifier_call = irq_notifier, 367 }; 368 369 static void __init irq_pm_init(void) 370 { 371 /* FIXME: Remove this when MPU OSWR support is added */ 372 if (!IS_PM44XX_ERRATUM(PM_OMAP4_CPU_OSWR_DISABLE)) 373 cpu_pm_register_notifier(&irq_notifier_block); 374 } 375 #else 376 static void __init irq_pm_init(void) 377 {} 378 #endif 379 380 void __iomem *omap_get_wakeupgen_base(void) 381 { 382 return wakeupgen_base; 383 } 384 385 int omap_secure_apis_support(void) 386 { 387 return omap_secure_apis; 388 } 389 390 static struct irq_chip wakeupgen_chip = { 391 .name = "WUGEN", 392 .irq_eoi = irq_chip_eoi_parent, 393 .irq_mask = wakeupgen_mask, 394 .irq_unmask = wakeupgen_unmask, 395 .irq_retrigger = irq_chip_retrigger_hierarchy, 396 .irq_set_type = irq_chip_set_type_parent, 397 .flags = IRQCHIP_SKIP_SET_WAKE | IRQCHIP_MASK_ON_SUSPEND, 398 #ifdef CONFIG_SMP 399 .irq_set_affinity = irq_chip_set_affinity_parent, 400 #endif 401 }; 402 403 static int wakeupgen_domain_xlate(struct irq_domain *domain, 404 struct device_node *controller, 405 const u32 *intspec, 406 unsigned int intsize, 407 unsigned long *out_hwirq, 408 unsigned int *out_type) 409 { 410 if (domain->of_node != controller) 411 return -EINVAL; /* Shouldn't happen, really... */ 412 if (intsize != 3) 413 return -EINVAL; /* Not GIC compliant */ 414 if (intspec[0] != 0) 415 return -EINVAL; /* No PPI should point to this domain */ 416 417 *out_hwirq = intspec[1]; 418 *out_type = intspec[2]; 419 return 0; 420 } 421 422 static int wakeupgen_domain_alloc(struct irq_domain *domain, 423 unsigned int virq, 424 unsigned int nr_irqs, void *data) 425 { 426 struct of_phandle_args *args = data; 427 struct of_phandle_args parent_args; 428 irq_hw_number_t hwirq; 429 int i; 430 431 if (args->args_count != 3) 432 return -EINVAL; /* Not GIC compliant */ 433 if (args->args[0] != 0) 434 return -EINVAL; /* No PPI should point to this domain */ 435 436 hwirq = args->args[1]; 437 if (hwirq >= MAX_IRQS) 438 return -EINVAL; /* Can't deal with this */ 439 440 for (i = 0; i < nr_irqs; i++) 441 irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i, 442 &wakeupgen_chip, NULL); 443 444 parent_args = *args; 445 parent_args.np = domain->parent->of_node; 446 return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &parent_args); 447 } 448 449 static const struct irq_domain_ops wakeupgen_domain_ops = { 450 .xlate = wakeupgen_domain_xlate, 451 .alloc = wakeupgen_domain_alloc, 452 .free = irq_domain_free_irqs_common, 453 }; 454 455 /* 456 * Initialise the wakeupgen module. 457 */ 458 static int __init wakeupgen_init(struct device_node *node, 459 struct device_node *parent) 460 { 461 struct irq_domain *parent_domain, *domain; 462 int i; 463 unsigned int boot_cpu = smp_processor_id(); 464 u32 val; 465 466 if (!parent) { 467 pr_err("%s: no parent, giving up\n", node->full_name); 468 return -ENODEV; 469 } 470 471 parent_domain = irq_find_host(parent); 472 if (!parent_domain) { 473 pr_err("%s: unable to obtain parent domain\n", node->full_name); 474 return -ENXIO; 475 } 476 /* Not supported on OMAP4 ES1.0 silicon */ 477 if (omap_rev() == OMAP4430_REV_ES1_0) { 478 WARN(1, "WakeupGen: Not supported on OMAP4430 ES1.0\n"); 479 return -EPERM; 480 } 481 482 /* Static mapping, never released */ 483 wakeupgen_base = of_iomap(node, 0); 484 if (WARN_ON(!wakeupgen_base)) 485 return -ENOMEM; 486 487 if (cpu_is_omap44xx()) { 488 irq_banks = OMAP4_NR_BANKS; 489 max_irqs = OMAP4_NR_IRQS; 490 omap_secure_apis = 1; 491 } else if (soc_is_am43xx()) { 492 irq_banks = AM43XX_NR_REG_BANKS; 493 max_irqs = AM43XX_IRQS; 494 } 495 496 domain = irq_domain_add_hierarchy(parent_domain, 0, max_irqs, 497 node, &wakeupgen_domain_ops, 498 NULL); 499 if (!domain) { 500 iounmap(wakeupgen_base); 501 return -ENOMEM; 502 } 503 504 /* Clear all IRQ bitmasks at wakeupGen level */ 505 for (i = 0; i < irq_banks; i++) { 506 wakeupgen_writel(0, i, CPU0_ID); 507 if (!soc_is_am43xx()) 508 wakeupgen_writel(0, i, CPU1_ID); 509 } 510 511 /* 512 * FIXME: Add support to set_smp_affinity() once the core 513 * GIC code has necessary hooks in place. 514 */ 515 516 /* Associate all the IRQs to boot CPU like GIC init does. */ 517 for (i = 0; i < max_irqs; i++) 518 irq_target_cpu[i] = boot_cpu; 519 520 /* 521 * Enables OMAP5 ES2 PM Mode using ES2_PM_MODE in AMBA_IF_MODE 522 * 0x0: ES1 behavior, CPU cores would enter and exit OFF mode together. 523 * 0x1: ES2 behavior, CPU cores are allowed to enter/exit OFF mode 524 * independently. 525 * This needs to be set one time thanks to always ON domain. 526 * 527 * We do not support ES1 behavior anymore. OMAP5 is assumed to be 528 * ES2.0, and the same is applicable for DRA7. 529 */ 530 if (soc_is_omap54xx() || soc_is_dra7xx()) { 531 val = __raw_readl(wakeupgen_base + OMAP_AMBA_IF_MODE); 532 val |= BIT(5); 533 omap_smc1(OMAP5_MON_AMBA_IF_INDEX, val); 534 } 535 536 irq_hotplug_init(); 537 irq_pm_init(); 538 539 return 0; 540 } 541 IRQCHIP_DECLARE(ti_wakeupgen, "ti,omap4-wugen-mpu", wakeupgen_init); 542