arch/arm/mach-omap2/pm24xx.c

   1 /*
   2  * OMAP2 Power Management Routines
   3  *
   4  * Copyright (C) 2005 Texas Instruments, Inc.
   5  * Copyright (C) 2006-2008 Nokia Corporation
   6  *
   7  * Written by:
   8  * Richard Woodruff <r-woodruff2@ti.com>
   9  * Tony Lindgren
  10  * Juha Yrjola
  11  * Amit Kucheria <amit.kucheria@nokia.com>
  12  * Igor Stoppa <igor.stoppa@nokia.com>
  13  *
  14  * Based on pm.c for omap1
  15  *
  16  * This program is free software; you can redistribute it and/or modify
  17  * it under the terms of the GNU General Public License version 2 as
  18  * published by the Free Software Foundation.
  19  */
  20
  21 #include <linux/suspend.h>
  22 #include <linux/sched.h>
  23 #include <linux/proc_fs.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/sysfs.h>
  26 #include <linux/module.h>
  27 #include <linux/delay.h>
  28 #include <linux/clk.h>
  29 #include <linux/io.h>
  30 #include <linux/irq.h>
  31 #include <linux/time.h>
  32 #include <linux/gpio.h>
  33 #include <linux/console.h>
  34
  35 #include <asm/mach/time.h>
  36 #include <asm/mach/irq.h>
  37 #include <asm/mach-types.h>
  38
  39 #include <mach/irqs.h>
  40 #include <plat/clock.h>
  41 #include <plat/sram.h>
  42 #include <plat/dma.h>
  43 #include <plat/board.h>
  44
  45 #include "prm2xxx_3xxx.h"
  46 #include "prm-regbits-24xx.h"
  47 #include "cm2xxx_3xxx.h"
  48 #include "cm-regbits-24xx.h"
  49 #include "sdrc.h"
  50 #include "pm.h"
  51 #include "control.h"
  52
  53 #include "powerdomain.h"
  54 #include "clockdomain.h"
  55
  56 #ifdef CONFIG_SUSPEND
  57 static suspend_state_t suspend_state = PM_SUSPEND_ON;
  58 static inline bool is_suspending(void)
  59 {
  60         return (suspend_state != PM_SUSPEND_ON);
  61 }
  62 #else
  63 static inline bool is_suspending(void)
  64 {
  65         return false;
  66 }
  67 #endif
  68
  69 static void (*omap2_sram_idle)(void);
  70 static void (*omap2_sram_suspend)(u32 dllctrl, void __iomem *sdrc_dlla_ctrl,
  71                                   void __iomem *sdrc_power);
  72
  73 static struct powerdomain *mpu_pwrdm, *core_pwrdm;
  74 static struct clockdomain *dsp_clkdm, *mpu_clkdm, *wkup_clkdm, *gfx_clkdm;
  75
  76 static struct clk *osc_ck, *emul_ck;
  77
  78 static int omap2_fclks_active(void)
  79 {
  80         u32 f1, f2;
  81
  82         f1 = omap2_cm_read_mod_reg(CORE_MOD, CM_FCLKEN1);
  83         f2 = omap2_cm_read_mod_reg(CORE_MOD, OMAP24XX_CM_FCLKEN2);
  84
  85         /* Ignore UART clocks.  These are handled by UART core (serial.c) */
  86         f1 &= ~(OMAP24XX_EN_UART1_MASK | OMAP24XX_EN_UART2_MASK);
  87         f2 &= ~OMAP24XX_EN_UART3_MASK;
  88
  89         if (f1 | f2)
  90                 return 1;
  91         return 0;
  92 }
  93
  94 static void omap2_enter_full_retention(void)
  95 {
  96         u32 l;
  97
  98         /* There is 1 reference hold for all children of the oscillator
  99          * clock, the following will remove it. If no one else uses the
 100          * oscillator itself it will be disabled if/when we enter retention
 101          * mode.
 102          */
 103         clk_disable(osc_ck);
 104
 105         /* Clear old wake-up events */
 106         /* REVISIT: These write to reserved bits? */
 107         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
 108         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
 109         omap2_prm_write_mod_reg(0xffffffff, WKUP_MOD, PM_WKST);
 110
 111         /*
 112          * Set MPU powerdomain's next power state to RETENTION;
 113          * preserve logic state during retention
 114          */
 115         pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
 116         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
 117
 118         /* Workaround to kill USB */
 119         l = omap_ctrl_readl(OMAP2_CONTROL_DEVCONF0) | OMAP24XX_USBSTANDBYCTRL;
 120         omap_ctrl_writel(l, OMAP2_CONTROL_DEVCONF0);
 121
 122         omap2_gpio_prepare_for_idle(0);
 123
 124         /* One last check for pending IRQs to avoid extra latency due
 125          * to sleeping unnecessarily. */
 126         if (omap_irq_pending())
 127                 goto no_sleep;
 128
 129         /* Block console output in case it is on one of the OMAP UARTs */
 130         if (!is_suspending())
 131                 if (!console_trylock())
 132                         goto no_sleep;
 133
 134         omap_uart_prepare_idle(0);
 135         omap_uart_prepare_idle(1);
 136         omap_uart_prepare_idle(2);
 137
 138         /* Jump to SRAM suspend code */
 139         omap2_sram_suspend(sdrc_read_reg(SDRC_DLLA_CTRL),
 140                            OMAP_SDRC_REGADDR(SDRC_DLLA_CTRL),
 141                            OMAP_SDRC_REGADDR(SDRC_POWER));
 142
 143         omap_uart_resume_idle(2);
 144         omap_uart_resume_idle(1);
 145         omap_uart_resume_idle(0);
 146
 147         if (!is_suspending())
 148                 console_unlock();
 149
 150 no_sleep:
 151         omap2_gpio_resume_after_idle();
 152
 153         clk_enable(osc_ck);
 154
 155         /* clear CORE wake-up events */
 156         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
 157         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
 158
 159         /* wakeup domain events - bit 1: GPT1, bit5 GPIO */
 160         omap2_prm_clear_mod_reg_bits(0x4 | 0x1, WKUP_MOD, PM_WKST);
 161
 162         /* MPU domain wake events */
 163         l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 164         if (l & 0x01)
 165                 omap2_prm_write_mod_reg(0x01, OCP_MOD,
 166                                   OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 167         if (l & 0x20)
 168                 omap2_prm_write_mod_reg(0x20, OCP_MOD,
 169                                   OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 170
 171         /* Mask future PRCM-to-MPU interrupts */
 172         omap2_prm_write_mod_reg(0x0, OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 173 }
 174
 175 static int omap2_i2c_active(void)
 176 {
 177         u32 l;
 178
 179         l = omap2_cm_read_mod_reg(CORE_MOD, CM_FCLKEN1);
 180         return l & (OMAP2420_EN_I2C2_MASK | OMAP2420_EN_I2C1_MASK);
 181 }
 182
 183 static int sti_console_enabled;
 184
 185 static int omap2_allow_mpu_retention(void)
 186 {
 187         u32 l;
 188
 189         /* Check for MMC, UART2, UART1, McSPI2, McSPI1 and DSS1. */
 190         l = omap2_cm_read_mod_reg(CORE_MOD, CM_FCLKEN1);
 191         if (l & (OMAP2420_EN_MMC_MASK | OMAP24XX_EN_UART2_MASK |
 192                  OMAP24XX_EN_UART1_MASK | OMAP24XX_EN_MCSPI2_MASK |
 193                  OMAP24XX_EN_MCSPI1_MASK | OMAP24XX_EN_DSS1_MASK))
 194                 return 0;
 195         /* Check for UART3. */
 196         l = omap2_cm_read_mod_reg(CORE_MOD, OMAP24XX_CM_FCLKEN2);
 197         if (l & OMAP24XX_EN_UART3_MASK)
 198                 return 0;
 199         if (sti_console_enabled)
 200                 return 0;
 201
 202         return 1;
 203 }
 204
 205 static void omap2_enter_mpu_retention(void)
 206 {
 207         int only_idle = 0;
 208
 209         /* Putting MPU into the WFI state while a transfer is active
 210          * seems to cause the I2C block to timeout. Why? Good question. */
 211         if (omap2_i2c_active())
 212                 return;
 213
 214         /* The peripherals seem not to be able to wake up the MPU when
 215          * it is in retention mode. */
 216         if (omap2_allow_mpu_retention()) {
 217                 /* REVISIT: These write to reserved bits? */
 218                 omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
 219                 omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
 220                 omap2_prm_write_mod_reg(0xffffffff, WKUP_MOD, PM_WKST);
 221
 222                 /* Try to enter MPU retention */
 223                 omap2_prm_write_mod_reg((0x01 << OMAP_POWERSTATE_SHIFT) |
 224                                   OMAP_LOGICRETSTATE_MASK,
 225                                   MPU_MOD, OMAP2_PM_PWSTCTRL);
 226         } else {
 227                 /* Block MPU retention */
 228
 229                 omap2_prm_write_mod_reg(OMAP_LOGICRETSTATE_MASK, MPU_MOD,
 230                                                  OMAP2_PM_PWSTCTRL);
 231                 only_idle = 1;
 232         }
 233
 234         omap2_sram_idle();
 235 }
 236
 237 static int omap2_can_sleep(void)
 238 {
 239         if (omap2_fclks_active())
 240                 return 0;
 241         if (!omap_uart_can_sleep())
 242                 return 0;
 243         if (osc_ck->usecount > 1)
 244                 return 0;
 245         if (omap_dma_running())
 246                 return 0;
 247
 248         return 1;
 249 }
 250
 251 static void omap2_pm_idle(void)
 252 {
 253         local_irq_disable();
 254
 255         if (!omap2_can_sleep()) {
 256                 if (omap_irq_pending())
 257                         goto out;
 258                 omap2_enter_mpu_retention();
 259                 goto out;
 260         }
 261
 262         if (omap_irq_pending())
 263                 goto out;
 264
 265         omap2_enter_full_retention();
 266
 267 out:
 268         local_irq_enable();
 269 }
 270
 271 #ifdef CONFIG_SUSPEND
 272 static int omap2_pm_begin(suspend_state_t state)
 273 {
 274         disable_hlt();
 275         suspend_state = state;
 276         return 0;
 277 }
 278
 279 static int omap2_pm_suspend(void)
 280 {
 281         u32 wken_wkup, mir1;
 282
 283         wken_wkup = omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
 284         wken_wkup &= ~OMAP24XX_EN_GPT1_MASK;
 285         omap2_prm_write_mod_reg(wken_wkup, WKUP_MOD, PM_WKEN);
 286
 287         /* Mask GPT1 */
 288         mir1 = omap_readl(0x480fe0a4);
 289         omap_writel(1 << 5, 0x480fe0ac);
 290
 291         omap_uart_prepare_suspend();
 292         omap2_enter_full_retention();
 293
 294         omap_writel(mir1, 0x480fe0a4);
 295         omap2_prm_write_mod_reg(wken_wkup, WKUP_MOD, PM_WKEN);
 296
 297         return 0;
 298 }
 299
 300 static int omap2_pm_enter(suspend_state_t state)
 301 {
 302         int ret = 0;
 303
 304         switch (state) {
 305         case PM_SUSPEND_STANDBY:
 306         case PM_SUSPEND_MEM:
 307                 ret = omap2_pm_suspend();
 308                 break;
 309         default:
 310                 ret = -EINVAL;
 311         }
 312
 313         return ret;
 314 }
 315
 316 static void omap2_pm_end(void)
 317 {
 318         suspend_state = PM_SUSPEND_ON;
 319         enable_hlt();
 320 }
 321
 322 static const struct platform_suspend_ops omap_pm_ops = {
 323         .begin          = omap2_pm_begin,
 324         .enter          = omap2_pm_enter,
 325         .end            = omap2_pm_end,
 326         .valid          = suspend_valid_only_mem,
 327 };
 328 #else
 329 static const struct platform_suspend_ops __initdata omap_pm_ops;
 330 #endif /* CONFIG_SUSPEND */
 331
 332 /* XXX This function should be shareable between OMAP2xxx and OMAP3 */
 333 static int __init clkdms_setup(struct clockdomain *clkdm, void *unused)
 334 {
 335         if (clkdm->flags & CLKDM_CAN_ENABLE_AUTO)
 336                 clkdm_allow_idle(clkdm);
 337         else if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP &&
 338                  atomic_read(&clkdm->usecount) == 0)
 339                 clkdm_sleep(clkdm);
 340         return 0;
 341 }
 342
 343 static void __init prcm_setup_regs(void)
 344 {
 345         int i, num_mem_banks;
 346         struct powerdomain *pwrdm;
 347
 348         /*
 349          * Enable autoidle
 350          * XXX This should be handled by hwmod code or PRCM init code
 351          */
 352         omap2_prm_write_mod_reg(OMAP24XX_AUTOIDLE_MASK, OCP_MOD,
 353                           OMAP2_PRCM_SYSCONFIG_OFFSET);
 354
 355         /*
 356          * Set CORE powerdomain memory banks to retain their contents
 357          * during RETENTION
 358          */
 359         num_mem_banks = pwrdm_get_mem_bank_count(core_pwrdm);
 360         for (i = 0; i < num_mem_banks; i++)
 361                 pwrdm_set_mem_retst(core_pwrdm, i, PWRDM_POWER_RET);
 362
 363         /* Set CORE powerdomain's next power state to RETENTION */
 364         pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_RET);
 365
 366         /*
 367          * Set MPU powerdomain's next power state to RETENTION;
 368          * preserve logic state during retention
 369          */
 370         pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
 371         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
 372
 373         /* Force-power down DSP, GFX powerdomains */
 374
 375         pwrdm = clkdm_get_pwrdm(dsp_clkdm);
 376         pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
 377         clkdm_sleep(dsp_clkdm);
 378
 379         pwrdm = clkdm_get_pwrdm(gfx_clkdm);
 380         pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
 381         clkdm_sleep(gfx_clkdm);
 382
 383         /* Enable hardware-supervised idle for all clkdms */
 384         clkdm_for_each(clkdms_setup, NULL);
 385         clkdm_add_wkdep(mpu_clkdm, wkup_clkdm);
 386
 387         /* REVISIT: Configure number of 32 kHz clock cycles for sys_clk
 388          * stabilisation */
 389         omap2_prm_write_mod_reg(15 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
 390                                 OMAP2_PRCM_CLKSSETUP_OFFSET);
 391
 392         /* Configure automatic voltage transition */
 393         omap2_prm_write_mod_reg(2 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
 394                                 OMAP2_PRCM_VOLTSETUP_OFFSET);
 395         omap2_prm_write_mod_reg(OMAP24XX_AUTO_EXTVOLT_MASK |
 396                                 (0x1 << OMAP24XX_SETOFF_LEVEL_SHIFT) |
 397                                 OMAP24XX_MEMRETCTRL_MASK |
 398                                 (0x1 << OMAP24XX_SETRET_LEVEL_SHIFT) |
 399                                 (0x0 << OMAP24XX_VOLT_LEVEL_SHIFT),
 400                                 OMAP24XX_GR_MOD, OMAP2_PRCM_VOLTCTRL_OFFSET);
 401
 402         /* Enable wake-up events */
 403         omap2_prm_write_mod_reg(OMAP24XX_EN_GPIOS_MASK | OMAP24XX_EN_GPT1_MASK,
 404                                 WKUP_MOD, PM_WKEN);
 405 }
 406
 407 static int __init omap2_pm_init(void)
 408 {
 409         u32 l;
 410
 411         if (!cpu_is_omap24xx())
 412                 return -ENODEV;
 413
 414         printk(KERN_INFO "Power Management for OMAP2 initializing\n");
 415         l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_REVISION_OFFSET);
 416         printk(KERN_INFO "PRCM revision %d.%d\n", (l >> 4) & 0x0f, l & 0x0f);
 417
 418         /* Look up important powerdomains */
 419
 420         mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
 421         if (!mpu_pwrdm)
 422                 pr_err("PM: mpu_pwrdm not found\n");
 423
 424         core_pwrdm = pwrdm_lookup("core_pwrdm");
 425         if (!core_pwrdm)
 426                 pr_err("PM: core_pwrdm not found\n");
 427
 428         /* Look up important clockdomains */
 429
 430         mpu_clkdm = clkdm_lookup("mpu_clkdm");
 431         if (!mpu_clkdm)
 432                 pr_err("PM: mpu_clkdm not found\n");
 433
 434         wkup_clkdm = clkdm_lookup("wkup_clkdm");
 435         if (!wkup_clkdm)
 436                 pr_err("PM: wkup_clkdm not found\n");
 437
 438         dsp_clkdm = clkdm_lookup("dsp_clkdm");
 439         if (!dsp_clkdm)
 440                 pr_err("PM: dsp_clkdm not found\n");
 441
 442         gfx_clkdm = clkdm_lookup("gfx_clkdm");
 443         if (!gfx_clkdm)
 444                 pr_err("PM: gfx_clkdm not found\n");
 445
 446
 447         osc_ck = clk_get(NULL, "osc_ck");
 448         if (IS_ERR(osc_ck)) {
 449                 printk(KERN_ERR "could not get osc_ck\n");
 450                 return -ENODEV;
 451         }
 452
 453         if (cpu_is_omap242x()) {
 454                 emul_ck = clk_get(NULL, "emul_ck");
 455                 if (IS_ERR(emul_ck)) {
 456                         printk(KERN_ERR "could not get emul_ck\n");
 457                         clk_put(osc_ck);
 458                         return -ENODEV;
 459                 }
 460         }
 461
 462         prcm_setup_regs();
 463
 464         /* Hack to prevent MPU retention when STI console is enabled. */
 465         {
 466                 const struct omap_sti_console_config *sti;
 467
 468                 sti = omap_get_config(OMAP_TAG_STI_CONSOLE,
 469                                       struct omap_sti_console_config);
 470                 if (sti != NULL && sti->enable)
 471                         sti_console_enabled = 1;
 472         }
 473
 474         /*
 475          * We copy the assembler sleep/wakeup routines to SRAM.
 476          * These routines need to be in SRAM as that's the only
 477          * memory the MPU can see when it wakes up.
 478          */
 479         if (cpu_is_omap24xx()) {
 480                 omap2_sram_idle = omap_sram_push(omap24xx_idle_loop_suspend,
 481                                                  omap24xx_idle_loop_suspend_sz);
 482
 483                 omap2_sram_suspend = omap_sram_push(omap24xx_cpu_suspend,
 484                                                     omap24xx_cpu_suspend_sz);
 485         }
 486
 487         suspend_set_ops(&omap_pm_ops);
 488         pm_idle = omap2_pm_idle;
 489
 490         return 0;
 491 }
 492
 493 late_initcall(omap2_pm_init);