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/irq.h>
  30 #include <linux/time.h>
  31 #include <linux/gpio.h>
  32 #include <linux/platform_data/gpio-omap.h>
  33
  34 #include <asm/mach/time.h>
  35 #include <asm/mach/irq.h>
  36 #include <asm/mach-types.h>
  37 #include <asm/system_misc.h>
  38
  39 #include <plat/clock.h>
  40 #include <plat-omap/dma-omap.h>
  41
  42 #include "../plat-omap/sram.h"
  43
  44 #include "common.h"
  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 #include "powerdomain.h"
  53 #include "clockdomain.h"
  54
  55 static void (*omap2_sram_idle)(void);
  56 static void (*omap2_sram_suspend)(u32 dllctrl, void __iomem *sdrc_dlla_ctrl,
  57                                   void __iomem *sdrc_power);
  58
  59 static struct powerdomain *mpu_pwrdm, *core_pwrdm;
  60 static struct clockdomain *dsp_clkdm, *mpu_clkdm, *wkup_clkdm, *gfx_clkdm;
  61
  62 static struct clk *osc_ck, *emul_ck;
  63
  64 static int omap2_fclks_active(void)
  65 {
  66         u32 f1, f2;
  67
  68         f1 = omap2_cm_read_mod_reg(CORE_MOD, CM_FCLKEN1);
  69         f2 = omap2_cm_read_mod_reg(CORE_MOD, OMAP24XX_CM_FCLKEN2);
  70
  71         return (f1 | f2) ? 1 : 0;
  72 }
  73
  74 static int omap2_enter_full_retention(void)
  75 {
  76         u32 l;
  77
  78         /* There is 1 reference hold for all children of the oscillator
  79          * clock, the following will remove it. If no one else uses the
  80          * oscillator itself it will be disabled if/when we enter retention
  81          * mode.
  82          */
  83         clk_disable(osc_ck);
  84
  85         /* Clear old wake-up events */
  86         /* REVISIT: These write to reserved bits? */
  87         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
  88         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
  89         omap2_prm_write_mod_reg(0xffffffff, WKUP_MOD, PM_WKST);
  90
  91         /*
  92          * Set MPU powerdomain's next power state to RETENTION;
  93          * preserve logic state during retention
  94          */
  95         pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
  96         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
  97
  98         /* Workaround to kill USB */
  99         l = omap_ctrl_readl(OMAP2_CONTROL_DEVCONF0) | OMAP24XX_USBSTANDBYCTRL;
 100         omap_ctrl_writel(l, OMAP2_CONTROL_DEVCONF0);
 101
 102         omap2_gpio_prepare_for_idle(0);
 103
 104         /* One last check for pending IRQs to avoid extra latency due
 105          * to sleeping unnecessarily. */
 106         if (omap_irq_pending())
 107                 goto no_sleep;
 108
 109         /* Jump to SRAM suspend code */
 110         omap2_sram_suspend(sdrc_read_reg(SDRC_DLLA_CTRL),
 111                            OMAP_SDRC_REGADDR(SDRC_DLLA_CTRL),
 112                            OMAP_SDRC_REGADDR(SDRC_POWER));
 113
 114 no_sleep:
 115         omap2_gpio_resume_after_idle();
 116
 117         clk_enable(osc_ck);
 118
 119         /* clear CORE wake-up events */
 120         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
 121         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
 122
 123         /* wakeup domain events - bit 1: GPT1, bit5 GPIO */
 124         omap2_prm_clear_mod_reg_bits(0x4 | 0x1, WKUP_MOD, PM_WKST);
 125
 126         /* MPU domain wake events */
 127         l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 128         if (l & 0x01)
 129                 omap2_prm_write_mod_reg(0x01, OCP_MOD,
 130                                   OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 131         if (l & 0x20)
 132                 omap2_prm_write_mod_reg(0x20, OCP_MOD,
 133                                   OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 134
 135         /* Mask future PRCM-to-MPU interrupts */
 136         omap2_prm_write_mod_reg(0x0, OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 137
 138         return 0;
 139 }
 140
 141 static int omap2_i2c_active(void)
 142 {
 143         u32 l;
 144
 145         l = omap2_cm_read_mod_reg(CORE_MOD, CM_FCLKEN1);
 146         return l & (OMAP2420_EN_I2C2_MASK | OMAP2420_EN_I2C1_MASK);
 147 }
 148
 149 static int sti_console_enabled;
 150
 151 static int omap2_allow_mpu_retention(void)
 152 {
 153         u32 l;
 154
 155         /* Check for MMC, UART2, UART1, McSPI2, McSPI1 and DSS1. */
 156         l = omap2_cm_read_mod_reg(CORE_MOD, CM_FCLKEN1);
 157         if (l & (OMAP2420_EN_MMC_MASK | OMAP24XX_EN_UART2_MASK |
 158                  OMAP24XX_EN_UART1_MASK | OMAP24XX_EN_MCSPI2_MASK |
 159                  OMAP24XX_EN_MCSPI1_MASK | OMAP24XX_EN_DSS1_MASK))
 160                 return 0;
 161         /* Check for UART3. */
 162         l = omap2_cm_read_mod_reg(CORE_MOD, OMAP24XX_CM_FCLKEN2);
 163         if (l & OMAP24XX_EN_UART3_MASK)
 164                 return 0;
 165         if (sti_console_enabled)
 166                 return 0;
 167
 168         return 1;
 169 }
 170
 171 static void omap2_enter_mpu_retention(void)
 172 {
 173         /* Putting MPU into the WFI state while a transfer is active
 174          * seems to cause the I2C block to timeout. Why? Good question. */
 175         if (omap2_i2c_active())
 176                 return;
 177
 178         /* The peripherals seem not to be able to wake up the MPU when
 179          * it is in retention mode. */
 180         if (omap2_allow_mpu_retention()) {
 181                 /* REVISIT: These write to reserved bits? */
 182                 omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
 183                 omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
 184                 omap2_prm_write_mod_reg(0xffffffff, WKUP_MOD, PM_WKST);
 185
 186                 /* Try to enter MPU retention */
 187                 omap2_prm_write_mod_reg((0x01 << OMAP_POWERSTATE_SHIFT) |
 188                                   OMAP_LOGICRETSTATE_MASK,
 189                                   MPU_MOD, OMAP2_PM_PWSTCTRL);
 190         } else {
 191                 /* Block MPU retention */
 192
 193                 omap2_prm_write_mod_reg(OMAP_LOGICRETSTATE_MASK, MPU_MOD,
 194                                                  OMAP2_PM_PWSTCTRL);
 195         }
 196
 197         omap2_sram_idle();
 198 }
 199
 200 static int omap2_can_sleep(void)
 201 {
 202         if (omap2_fclks_active())
 203                 return 0;
 204         if (osc_ck->usecount > 1)
 205                 return 0;
 206         if (omap_dma_running())
 207                 return 0;
 208
 209         return 1;
 210 }
 211
 212 static void omap2_pm_idle(void)
 213 {
 214         local_fiq_disable();
 215
 216         if (!omap2_can_sleep()) {
 217                 if (omap_irq_pending())
 218                         goto out;
 219                 omap2_enter_mpu_retention();
 220                 goto out;
 221         }
 222
 223         if (omap_irq_pending())
 224                 goto out;
 225
 226         omap2_enter_full_retention();
 227
 228 out:
 229         local_fiq_enable();
 230 }
 231
 232 static void __init prcm_setup_regs(void)
 233 {
 234         int i, num_mem_banks;
 235         struct powerdomain *pwrdm;
 236
 237         /*
 238          * Enable autoidle
 239          * XXX This should be handled by hwmod code or PRCM init code
 240          */
 241         omap2_prm_write_mod_reg(OMAP24XX_AUTOIDLE_MASK, OCP_MOD,
 242                           OMAP2_PRCM_SYSCONFIG_OFFSET);
 243
 244         /*
 245          * Set CORE powerdomain memory banks to retain their contents
 246          * during RETENTION
 247          */
 248         num_mem_banks = pwrdm_get_mem_bank_count(core_pwrdm);
 249         for (i = 0; i < num_mem_banks; i++)
 250                 pwrdm_set_mem_retst(core_pwrdm, i, PWRDM_POWER_RET);
 251
 252         /* Set CORE powerdomain's next power state to RETENTION */
 253         pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_RET);
 254
 255         /*
 256          * Set MPU powerdomain's next power state to RETENTION;
 257          * preserve logic state during retention
 258          */
 259         pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
 260         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
 261
 262         /* Force-power down DSP, GFX powerdomains */
 263
 264         pwrdm = clkdm_get_pwrdm(dsp_clkdm);
 265         pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
 266         clkdm_sleep(dsp_clkdm);
 267
 268         pwrdm = clkdm_get_pwrdm(gfx_clkdm);
 269         pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
 270         clkdm_sleep(gfx_clkdm);
 271
 272         /* Enable hardware-supervised idle for all clkdms */
 273         clkdm_for_each(omap_pm_clkdms_setup, NULL);
 274         clkdm_add_wkdep(mpu_clkdm, wkup_clkdm);
 275
 276 #ifdef CONFIG_SUSPEND
 277         omap_pm_suspend = omap2_enter_full_retention;
 278 #endif
 279
 280         /* REVISIT: Configure number of 32 kHz clock cycles for sys_clk
 281          * stabilisation */
 282         omap2_prm_write_mod_reg(15 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
 283                                 OMAP2_PRCM_CLKSSETUP_OFFSET);
 284
 285         /* Configure automatic voltage transition */
 286         omap2_prm_write_mod_reg(2 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
 287                                 OMAP2_PRCM_VOLTSETUP_OFFSET);
 288         omap2_prm_write_mod_reg(OMAP24XX_AUTO_EXTVOLT_MASK |
 289                                 (0x1 << OMAP24XX_SETOFF_LEVEL_SHIFT) |
 290                                 OMAP24XX_MEMRETCTRL_MASK |
 291                                 (0x1 << OMAP24XX_SETRET_LEVEL_SHIFT) |
 292                                 (0x0 << OMAP24XX_VOLT_LEVEL_SHIFT),
 293                                 OMAP24XX_GR_MOD, OMAP2_PRCM_VOLTCTRL_OFFSET);
 294
 295         /* Enable wake-up events */
 296         omap2_prm_write_mod_reg(OMAP24XX_EN_GPIOS_MASK | OMAP24XX_EN_GPT1_MASK,
 297                                 WKUP_MOD, PM_WKEN);
 298 }
 299
 300 int __init omap2_pm_init(void)
 301 {
 302         u32 l;
 303
 304         printk(KERN_INFO "Power Management for OMAP2 initializing\n");
 305         l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_REVISION_OFFSET);
 306         printk(KERN_INFO "PRCM revision %d.%d\n", (l >> 4) & 0x0f, l & 0x0f);
 307
 308         /* Look up important powerdomains */
 309
 310         mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
 311         if (!mpu_pwrdm)
 312                 pr_err("PM: mpu_pwrdm not found\n");
 313
 314         core_pwrdm = pwrdm_lookup("core_pwrdm");
 315         if (!core_pwrdm)
 316                 pr_err("PM: core_pwrdm not found\n");
 317
 318         /* Look up important clockdomains */
 319
 320         mpu_clkdm = clkdm_lookup("mpu_clkdm");
 321         if (!mpu_clkdm)
 322                 pr_err("PM: mpu_clkdm not found\n");
 323
 324         wkup_clkdm = clkdm_lookup("wkup_clkdm");
 325         if (!wkup_clkdm)
 326                 pr_err("PM: wkup_clkdm not found\n");
 327
 328         dsp_clkdm = clkdm_lookup("dsp_clkdm");
 329         if (!dsp_clkdm)
 330                 pr_err("PM: dsp_clkdm not found\n");
 331
 332         gfx_clkdm = clkdm_lookup("gfx_clkdm");
 333         if (!gfx_clkdm)
 334                 pr_err("PM: gfx_clkdm not found\n");
 335
 336
 337         osc_ck = clk_get(NULL, "osc_ck");
 338         if (IS_ERR(osc_ck)) {
 339                 printk(KERN_ERR "could not get osc_ck\n");
 340                 return -ENODEV;
 341         }
 342
 343         if (cpu_is_omap242x()) {
 344                 emul_ck = clk_get(NULL, "emul_ck");
 345                 if (IS_ERR(emul_ck)) {
 346                         printk(KERN_ERR "could not get emul_ck\n");
 347                         clk_put(osc_ck);
 348                         return -ENODEV;
 349                 }
 350         }
 351
 352         prcm_setup_regs();
 353
 354         /*
 355          * We copy the assembler sleep/wakeup routines to SRAM.
 356          * These routines need to be in SRAM as that's the only
 357          * memory the MPU can see when it wakes up.
 358          */
 359         omap2_sram_idle = omap_sram_push(omap24xx_idle_loop_suspend,
 360                                          omap24xx_idle_loop_suspend_sz);
 361
 362         omap2_sram_suspend = omap_sram_push(omap24xx_cpu_suspend,
 363                                             omap24xx_cpu_suspend_sz);
 364
 365         arm_pm_idle = omap2_pm_idle;
 366
 367         return 0;
 368 }