arch/arm/mach-omap2/omap-wakeupgen.c

   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/platform_device.h>
  24 #include <linux/cpu.h>
  25 #include <linux/notifier.h>
  26 #include <linux/cpu_pm.h>
  27 #include <linux/irqchip/arm-gic.h>
  28
  29 #include "omap-wakeupgen.h"
  30 #include "omap-secure.h"
  31
  32 #include "soc.h"
  33 #include "omap4-sar-layout.h"
  34 #include "common.h"
  35
  36 #define MAX_NR_REG_BANKS        5
  37 #define MAX_IRQS                160
  38 #define WKG_MASK_ALL            0x00000000
  39 #define WKG_UNMASK_ALL          0xffffffff
  40 #define CPU_ENA_OFFSET          0x400
  41 #define CPU0_ID                 0x0
  42 #define CPU1_ID                 0x1
  43 #define OMAP4_NR_BANKS          4
  44 #define OMAP4_NR_IRQS           128
  45
  46 static void __iomem *wakeupgen_base;
  47 static void __iomem *sar_base;
  48 static DEFINE_RAW_SPINLOCK(wakeupgen_lock);
  49 static unsigned int irq_target_cpu[MAX_IRQS];
  50 static unsigned int irq_banks = MAX_NR_REG_BANKS;
  51 static unsigned int max_irqs = MAX_IRQS;
  52 static unsigned int omap_secure_apis;
  53
  54 /*
  55  * Static helper functions.
  56  */
  57 static inline u32 wakeupgen_readl(u8 idx, u32 cpu)
  58 {
  59         return __raw_readl(wakeupgen_base + OMAP_WKG_ENB_A_0 +
  60                                 (cpu * CPU_ENA_OFFSET) + (idx * 4));
  61 }
  62
  63 static inline void wakeupgen_writel(u32 val, u8 idx, u32 cpu)
  64 {
  65         __raw_writel(val, wakeupgen_base + OMAP_WKG_ENB_A_0 +
  66                                 (cpu * CPU_ENA_OFFSET) + (idx * 4));
  67 }
  68
  69 static inline void sar_writel(u32 val, u32 offset, u8 idx)
  70 {
  71         __raw_writel(val, sar_base + offset + (idx * 4));
  72 }
  73
  74 static inline int _wakeupgen_get_irq_info(u32 irq, u32 *bit_posn, u8 *reg_index)
  75 {
  76         unsigned int spi_irq;
  77
  78         /*
  79          * PPIs and SGIs are not supported.
  80          */
  81         if (irq < OMAP44XX_IRQ_GIC_START)
  82                 return -EINVAL;
  83
  84         /*
  85          * Subtract the GIC offset.
  86          */
  87         spi_irq = irq - OMAP44XX_IRQ_GIC_START;
  88         if (spi_irq > MAX_IRQS) {
  89                 pr_err("omap wakeupGen: Invalid IRQ%d\n", irq);
  90                 return -EINVAL;
  91         }
  92
  93         /*
  94          * Each WakeupGen register controls 32 interrupt.
  95          * i.e. 1 bit per SPI IRQ
  96          */
  97         *reg_index = spi_irq >> 5;
  98         *bit_posn = spi_irq %= 32;
  99
 100         return 0;
 101 }
 102
 103 static void _wakeupgen_clear(unsigned int irq, unsigned int cpu)
 104 {
 105         u32 val, bit_number;
 106         u8 i;
 107
 108         if (_wakeupgen_get_irq_info(irq, &bit_number, &i))
 109                 return;
 110
 111         val = wakeupgen_readl(i, cpu);
 112         val &= ~BIT(bit_number);
 113         wakeupgen_writel(val, i, cpu);
 114 }
 115
 116 static void _wakeupgen_set(unsigned int irq, unsigned int cpu)
 117 {
 118         u32 val, bit_number;
 119         u8 i;
 120
 121         if (_wakeupgen_get_irq_info(irq, &bit_number, &i))
 122                 return;
 123
 124         val = wakeupgen_readl(i, cpu);
 125         val |= BIT(bit_number);
 126         wakeupgen_writel(val, i, cpu);
 127 }
 128
 129 /*
 130  * Architecture specific Mask extension
 131  */
 132 static void wakeupgen_mask(struct irq_data *d)
 133 {
 134         unsigned long flags;
 135
 136         raw_spin_lock_irqsave(&wakeupgen_lock, flags);
 137         _wakeupgen_clear(d->irq, irq_target_cpu[d->irq]);
 138         raw_spin_unlock_irqrestore(&wakeupgen_lock, flags);
 139 }
 140
 141 /*
 142  * Architecture specific Unmask extension
 143  */
 144 static void wakeupgen_unmask(struct irq_data *d)
 145 {
 146         unsigned long flags;
 147
 148         raw_spin_lock_irqsave(&wakeupgen_lock, flags);
 149         _wakeupgen_set(d->irq, irq_target_cpu[d->irq]);
 150         raw_spin_unlock_irqrestore(&wakeupgen_lock, flags);
 151 }
 152
 153 #ifdef CONFIG_HOTPLUG_CPU
 154 static DEFINE_PER_CPU(u32 [MAX_NR_REG_BANKS], irqmasks);
 155
 156 static void _wakeupgen_save_masks(unsigned int cpu)
 157 {
 158         u8 i;
 159
 160         for (i = 0; i < irq_banks; i++)
 161                 per_cpu(irqmasks, cpu)[i] = wakeupgen_readl(i, cpu);
 162 }
 163
 164 static void _wakeupgen_restore_masks(unsigned int cpu)
 165 {
 166         u8 i;
 167
 168         for (i = 0; i < irq_banks; i++)
 169                 wakeupgen_writel(per_cpu(irqmasks, cpu)[i], i, cpu);
 170 }
 171
 172 static void _wakeupgen_set_all(unsigned int cpu, unsigned int reg)
 173 {
 174         u8 i;
 175
 176         for (i = 0; i < irq_banks; i++)
 177                 wakeupgen_writel(reg, i, cpu);
 178 }
 179
 180 /*
 181  * Mask or unmask all interrupts on given CPU.
 182  *      0 = Mask all interrupts on the 'cpu'
 183  *      1 = Unmask all interrupts on the 'cpu'
 184  * Ensure that the initial mask is maintained. This is faster than
 185  * iterating through GIC registers to arrive at the correct masks.
 186  */
 187 static void wakeupgen_irqmask_all(unsigned int cpu, unsigned int set)
 188 {
 189         unsigned long flags;
 190
 191         raw_spin_lock_irqsave(&wakeupgen_lock, flags);
 192         if (set) {
 193                 _wakeupgen_save_masks(cpu);
 194                 _wakeupgen_set_all(cpu, WKG_MASK_ALL);
 195         } else {
 196                 _wakeupgen_set_all(cpu, WKG_UNMASK_ALL);
 197                 _wakeupgen_restore_masks(cpu);
 198         }
 199         raw_spin_unlock_irqrestore(&wakeupgen_lock, flags);
 200 }
 201 #endif
 202
 203 #ifdef CONFIG_CPU_PM
 204 static inline void omap4_irq_save_context(void)
 205 {
 206         u32 i, val;
 207
 208         if (omap_rev() == OMAP4430_REV_ES1_0)
 209                 return;
 210
 211         for (i = 0; i < irq_banks; i++) {
 212                 /* Save the CPUx interrupt mask for IRQ 0 to 127 */
 213                 val = wakeupgen_readl(i, 0);
 214                 sar_writel(val, WAKEUPGENENB_OFFSET_CPU0, i);
 215                 val = wakeupgen_readl(i, 1);
 216                 sar_writel(val, WAKEUPGENENB_OFFSET_CPU1, i);
 217
 218                 /*
 219                  * Disable the secure interrupts for CPUx. The restore
 220                  * code blindly restores secure and non-secure interrupt
 221                  * masks from SAR RAM. Secure interrupts are not suppose
 222                  * to be enabled from HLOS. So overwrite the SAR location
 223                  * so that the secure interrupt remains disabled.
 224                  */
 225                 sar_writel(0x0, WAKEUPGENENB_SECURE_OFFSET_CPU0, i);
 226                 sar_writel(0x0, WAKEUPGENENB_SECURE_OFFSET_CPU1, i);
 227         }
 228
 229         /* Save AuxBoot* registers */
 230         val = __raw_readl(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
 231         __raw_writel(val, sar_base + AUXCOREBOOT0_OFFSET);
 232         val = __raw_readl(wakeupgen_base + OMAP_AUX_CORE_BOOT_1);
 233         __raw_writel(val, sar_base + AUXCOREBOOT1_OFFSET);
 234
 235         /* Save SyncReq generation logic */
 236         val = __raw_readl(wakeupgen_base + OMAP_PTMSYNCREQ_MASK);
 237         __raw_writel(val, sar_base + PTMSYNCREQ_MASK_OFFSET);
 238         val = __raw_readl(wakeupgen_base + OMAP_PTMSYNCREQ_EN);
 239         __raw_writel(val, sar_base + PTMSYNCREQ_EN_OFFSET);
 240
 241         /* Set the Backup Bit Mask status */
 242         val = __raw_readl(sar_base + SAR_BACKUP_STATUS_OFFSET);
 243         val |= SAR_BACKUP_STATUS_WAKEUPGEN;
 244         __raw_writel(val, sar_base + SAR_BACKUP_STATUS_OFFSET);
 245
 246 }
 247
 248 static inline void omap5_irq_save_context(void)
 249 {
 250         u32 i, val;
 251
 252         for (i = 0; i < irq_banks; i++) {
 253                 /* Save the CPUx interrupt mask for IRQ 0 to 159 */
 254                 val = wakeupgen_readl(i, 0);
 255                 sar_writel(val, OMAP5_WAKEUPGENENB_OFFSET_CPU0, i);
 256                 val = wakeupgen_readl(i, 1);
 257                 sar_writel(val, OMAP5_WAKEUPGENENB_OFFSET_CPU1, i);
 258                 sar_writel(0x0, OMAP5_WAKEUPGENENB_SECURE_OFFSET_CPU0, i);
 259                 sar_writel(0x0, OMAP5_WAKEUPGENENB_SECURE_OFFSET_CPU1, i);
 260         }
 261
 262         /* Save AuxBoot* registers */
 263         val = __raw_readl(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
 264         __raw_writel(val, sar_base + OMAP5_AUXCOREBOOT0_OFFSET);
 265         val = __raw_readl(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
 266         __raw_writel(val, sar_base + OMAP5_AUXCOREBOOT1_OFFSET);
 267
 268         /* Set the Backup Bit Mask status */
 269         val = __raw_readl(sar_base + OMAP5_SAR_BACKUP_STATUS_OFFSET);
 270         val |= SAR_BACKUP_STATUS_WAKEUPGEN;
 271         __raw_writel(val, sar_base + OMAP5_SAR_BACKUP_STATUS_OFFSET);
 272
 273 }
 274
 275 /*
 276  * Save WakeupGen interrupt context in SAR BANK3. Restore is done by
 277  * ROM code. WakeupGen IP is integrated along with GIC to manage the
 278  * interrupt wakeups from CPU low power states. It manages
 279  * masking/unmasking of Shared peripheral interrupts(SPI). So the
 280  * interrupt enable/disable control should be in sync and consistent
 281  * at WakeupGen and GIC so that interrupts are not lost.
 282  */
 283 static void irq_save_context(void)
 284 {
 285         if (!sar_base)
 286                 sar_base = omap4_get_sar_ram_base();
 287
 288         if (soc_is_omap54xx())
 289                 omap5_irq_save_context();
 290         else
 291                 omap4_irq_save_context();
 292 }
 293
 294 /*
 295  * Clear WakeupGen SAR backup status.
 296  */
 297 static void irq_sar_clear(void)
 298 {
 299         u32 val;
 300         u32 offset = SAR_BACKUP_STATUS_OFFSET;
 301
 302         if (soc_is_omap54xx())
 303                 offset = OMAP5_SAR_BACKUP_STATUS_OFFSET;
 304
 305         val = __raw_readl(sar_base + offset);
 306         val &= ~SAR_BACKUP_STATUS_WAKEUPGEN;
 307         __raw_writel(val, sar_base + offset);
 308 }
 309
 310 /*
 311  * Save GIC and Wakeupgen interrupt context using secure API
 312  * for HS/EMU devices.
 313  */
 314 static void irq_save_secure_context(void)
 315 {
 316         u32 ret;
 317         ret = omap_secure_dispatcher(OMAP4_HAL_SAVEGIC_INDEX,
 318                                 FLAG_START_CRITICAL,
 319                                 0, 0, 0, 0, 0);
 320         if (ret != API_HAL_RET_VALUE_OK)
 321                 pr_err("GIC and Wakeupgen context save failed\n");
 322 }
 323 #endif
 324
 325 #ifdef CONFIG_HOTPLUG_CPU
 326 static int __cpuinit irq_cpu_hotplug_notify(struct notifier_block *self,
 327                                          unsigned long action, void *hcpu)
 328 {
 329         unsigned int cpu = (unsigned int)hcpu;
 330
 331         switch (action) {
 332         case CPU_ONLINE:
 333                 wakeupgen_irqmask_all(cpu, 0);
 334                 break;
 335         case CPU_DEAD:
 336                 wakeupgen_irqmask_all(cpu, 1);
 337                 break;
 338         }
 339         return NOTIFY_OK;
 340 }
 341
 342 static struct notifier_block __refdata irq_hotplug_notifier = {
 343         .notifier_call = irq_cpu_hotplug_notify,
 344 };
 345
 346 static void __init irq_hotplug_init(void)
 347 {
 348         register_hotcpu_notifier(&irq_hotplug_notifier);
 349 }
 350 #else
 351 static void __init irq_hotplug_init(void)
 352 {}
 353 #endif
 354
 355 #ifdef CONFIG_CPU_PM
 356 static int irq_notifier(struct notifier_block *self, unsigned long cmd, void *v)
 357 {
 358         switch (cmd) {
 359         case CPU_CLUSTER_PM_ENTER:
 360                 if (omap_type() == OMAP2_DEVICE_TYPE_GP)
 361                         irq_save_context();
 362                 else
 363                         irq_save_secure_context();
 364                 break;
 365         case CPU_CLUSTER_PM_EXIT:
 366                 if (omap_type() == OMAP2_DEVICE_TYPE_GP)
 367                         irq_sar_clear();
 368                 break;
 369         }
 370         return NOTIFY_OK;
 371 }
 372
 373 static struct notifier_block irq_notifier_block = {
 374         .notifier_call = irq_notifier,
 375 };
 376
 377 static void __init irq_pm_init(void)
 378 {
 379         /* FIXME: Remove this when MPU OSWR support is added */
 380         if (!soc_is_omap54xx())
 381                 cpu_pm_register_notifier(&irq_notifier_block);
 382 }
 383 #else
 384 static void __init irq_pm_init(void)
 385 {}
 386 #endif
 387
 388 void __iomem *omap_get_wakeupgen_base(void)
 389 {
 390         return wakeupgen_base;
 391 }
 392
 393 int omap_secure_apis_support(void)
 394 {
 395         return omap_secure_apis;
 396 }
 397
 398 /*
 399  * Initialise the wakeupgen module.
 400  */
 401 int __init omap_wakeupgen_init(void)
 402 {
 403         int i;
 404         unsigned int boot_cpu = smp_processor_id();
 405
 406         /* Not supported on OMAP4 ES1.0 silicon */
 407         if (omap_rev() == OMAP4430_REV_ES1_0) {
 408                 WARN(1, "WakeupGen: Not supported on OMAP4430 ES1.0\n");
 409                 return -EPERM;
 410         }
 411
 412         /* Static mapping, never released */
 413         wakeupgen_base = ioremap(OMAP_WKUPGEN_BASE, SZ_4K);
 414         if (WARN_ON(!wakeupgen_base))
 415                 return -ENOMEM;
 416
 417         if (cpu_is_omap44xx()) {
 418                 irq_banks = OMAP4_NR_BANKS;
 419                 max_irqs = OMAP4_NR_IRQS;
 420                 omap_secure_apis = 1;
 421         }
 422
 423         /* Clear all IRQ bitmasks at wakeupGen level */
 424         for (i = 0; i < irq_banks; i++) {
 425                 wakeupgen_writel(0, i, CPU0_ID);
 426                 wakeupgen_writel(0, i, CPU1_ID);
 427         }
 428
 429         /*
 430          * Override GIC architecture specific functions to add
 431          * OMAP WakeupGen interrupt controller along with GIC
 432          */
 433         gic_arch_extn.irq_mask = wakeupgen_mask;
 434         gic_arch_extn.irq_unmask = wakeupgen_unmask;
 435         gic_arch_extn.flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_SKIP_SET_WAKE;
 436
 437         /*
 438          * FIXME: Add support to set_smp_affinity() once the core
 439          * GIC code has necessary hooks in place.
 440          */
 441
 442         /* Associate all the IRQs to boot CPU like GIC init does. */
 443         for (i = 0; i < max_irqs; i++)
 444                 irq_target_cpu[i] = boot_cpu;
 445
 446         irq_hotplug_init();
 447         irq_pm_init();
 448
 449         return 0;
 450 }