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/clk-provider.h>
  30 #include <linux/irq.h>
  31 #include <linux/time.h>
  32 #include <linux/gpio.h>
  33 #include <linux/platform_data/gpio-omap.h>
  34
  35 #include <asm/fncpy.h>
  36
  37 #include <asm/mach/time.h>
  38 #include <asm/mach/irq.h>
  39 #include <asm/mach-types.h>
  40 #include <asm/system_misc.h>
  41
  42 #include <linux/omap-dma.h>
  43
  44 #include "soc.h"
  45 #include "common.h"
  46 #include "clock.h"
  47 #include "prm2xxx.h"
  48 #include "prm-regbits-24xx.h"
  49 #include "cm2xxx.h"
  50 #include "cm-regbits-24xx.h"
  51 #include "sdrc.h"
  52 #include "sram.h"
  53 #include "pm.h"
  54 #include "control.h"
  55 #include "powerdomain.h"
  56 #include "clockdomain.h"
  57
  58 static void (*omap2_sram_suspend)(u32 dllctrl, void __iomem *sdrc_dlla_ctrl,
  59                                   void __iomem *sdrc_power);
  60
  61 static struct powerdomain *mpu_pwrdm, *core_pwrdm;
  62 static struct clockdomain *dsp_clkdm, *mpu_clkdm, *wkup_clkdm, *gfx_clkdm;
  63
  64 static struct clk *osc_ck, *emul_ck;
  65
  66 static int omap2_enter_full_retention(void)
  67 {
  68         u32 l;
  69
  70         /* There is 1 reference hold for all children of the oscillator
  71          * clock, the following will remove it. If no one else uses the
  72          * oscillator itself it will be disabled if/when we enter retention
  73          * mode.
  74          */
  75         clk_disable(osc_ck);
  76
  77         /* Clear old wake-up events */
  78         /* REVISIT: These write to reserved bits? */
  79         omap_prm_clear_mod_irqs(CORE_MOD, PM_WKST1, ~0);
  80         omap_prm_clear_mod_irqs(CORE_MOD, OMAP24XX_PM_WKST2, ~0);
  81         omap_prm_clear_mod_irqs(WKUP_MOD, PM_WKST, ~0);
  82
  83         pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_RET);
  84         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
  85
  86         /* Workaround to kill USB */
  87         l = omap_ctrl_readl(OMAP2_CONTROL_DEVCONF0) | OMAP24XX_USBSTANDBYCTRL;
  88         omap_ctrl_writel(l, OMAP2_CONTROL_DEVCONF0);
  89
  90         omap2_gpio_prepare_for_idle(0);
  91
  92         /* One last check for pending IRQs to avoid extra latency due
  93          * to sleeping unnecessarily. */
  94         if (omap_irq_pending())
  95                 goto no_sleep;
  96
  97         /* Jump to SRAM suspend code */
  98         omap2_sram_suspend(sdrc_read_reg(SDRC_DLLA_CTRL),
  99                            OMAP_SDRC_REGADDR(SDRC_DLLA_CTRL),
 100                            OMAP_SDRC_REGADDR(SDRC_POWER));
 101
 102 no_sleep:
 103         omap2_gpio_resume_after_idle();
 104
 105         clk_enable(osc_ck);
 106
 107         /* clear CORE wake-up events */
 108         omap_prm_clear_mod_irqs(CORE_MOD, PM_WKST1, ~0);
 109         omap_prm_clear_mod_irqs(CORE_MOD, OMAP24XX_PM_WKST2, ~0);
 110
 111         /* wakeup domain events - bit 1: GPT1, bit5 GPIO */
 112         omap_prm_clear_mod_irqs(WKUP_MOD, PM_WKST, 0x4 | 0x1);
 113
 114         /* MPU domain wake events */
 115         omap_prm_clear_mod_irqs(OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET, 0x1);
 116
 117         omap_prm_clear_mod_irqs(OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET, 0x20);
 118
 119         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
 120         pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_ON);
 121
 122         return 0;
 123 }
 124
 125 static int sti_console_enabled;
 126
 127 static int omap2_allow_mpu_retention(void)
 128 {
 129         if (!omap2xxx_cm_mpu_retention_allowed())
 130                 return 0;
 131         if (sti_console_enabled)
 132                 return 0;
 133
 134         return 1;
 135 }
 136
 137 static void omap2_enter_mpu_retention(void)
 138 {
 139         const int zero = 0;
 140
 141         /* The peripherals seem not to be able to wake up the MPU when
 142          * it is in retention mode. */
 143         if (omap2_allow_mpu_retention()) {
 144                 /* REVISIT: These write to reserved bits? */
 145                 omap_prm_clear_mod_irqs(CORE_MOD, PM_WKST1, ~0);
 146                 omap_prm_clear_mod_irqs(CORE_MOD, OMAP24XX_PM_WKST2, ~0);
 147                 omap_prm_clear_mod_irqs(WKUP_MOD, PM_WKST, ~0);
 148
 149                 /* Try to enter MPU retention */
 150                 pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
 151
 152         } else {
 153                 /* Block MPU retention */
 154                 pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
 155         }
 156
 157         /* WFI */
 158         asm("mcr p15, 0, %0, c7, c0, 4" : : "r" (zero) : "memory", "cc");
 159
 160         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
 161 }
 162
 163 static int omap2_can_sleep(void)
 164 {
 165         if (omap2xxx_cm_fclks_active())
 166                 return 0;
 167         if (__clk_is_enabled(osc_ck))
 168                 return 0;
 169         if (omap_dma_running())
 170                 return 0;
 171
 172         return 1;
 173 }
 174
 175 static void omap2_pm_idle(void)
 176 {
 177         if (!omap2_can_sleep()) {
 178                 if (omap_irq_pending())
 179                         return;
 180                 omap2_enter_mpu_retention();
 181                 return;
 182         }
 183
 184         if (omap_irq_pending())
 185                 return;
 186
 187         omap2_enter_full_retention();
 188 }
 189
 190 static void __init prcm_setup_regs(void)
 191 {
 192         int i, num_mem_banks;
 193         struct powerdomain *pwrdm;
 194
 195         /*
 196          * Enable autoidle
 197          * XXX This should be handled by hwmod code or PRCM init code
 198          */
 199         omap2_prm_write_mod_reg(OMAP24XX_AUTOIDLE_MASK, OCP_MOD,
 200                           OMAP2_PRCM_SYSCONFIG_OFFSET);
 201
 202         /*
 203          * Set CORE powerdomain memory banks to retain their contents
 204          * during RETENTION
 205          */
 206         num_mem_banks = pwrdm_get_mem_bank_count(core_pwrdm);
 207         for (i = 0; i < num_mem_banks; i++)
 208                 pwrdm_set_mem_retst(core_pwrdm, i, PWRDM_POWER_RET);
 209
 210         pwrdm_set_logic_retst(core_pwrdm, PWRDM_POWER_RET);
 211
 212         pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
 213
 214         /* Force-power down DSP, GFX powerdomains */
 215
 216         pwrdm = clkdm_get_pwrdm(dsp_clkdm);
 217         pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
 218
 219         pwrdm = clkdm_get_pwrdm(gfx_clkdm);
 220         pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
 221
 222         /* Enable hardware-supervised idle for all clkdms */
 223         clkdm_for_each(omap_pm_clkdms_setup, NULL);
 224         clkdm_add_wkdep(mpu_clkdm, wkup_clkdm);
 225
 226         omap_common_suspend_init(omap2_enter_full_retention);
 227
 228         /* REVISIT: Configure number of 32 kHz clock cycles for sys_clk
 229          * stabilisation */
 230         omap2_prm_write_mod_reg(15 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
 231                                 OMAP2_PRCM_CLKSSETUP_OFFSET);
 232
 233         /* Configure automatic voltage transition */
 234         omap2_prm_write_mod_reg(2 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
 235                                 OMAP2_PRCM_VOLTSETUP_OFFSET);
 236         omap2_prm_write_mod_reg(OMAP24XX_AUTO_EXTVOLT_MASK |
 237                                 (0x1 << OMAP24XX_SETOFF_LEVEL_SHIFT) |
 238                                 OMAP24XX_MEMRETCTRL_MASK |
 239                                 (0x1 << OMAP24XX_SETRET_LEVEL_SHIFT) |
 240                                 (0x0 << OMAP24XX_VOLT_LEVEL_SHIFT),
 241                                 OMAP24XX_GR_MOD, OMAP2_PRCM_VOLTCTRL_OFFSET);
 242
 243         /* Enable wake-up events */
 244         omap2_prm_write_mod_reg(OMAP24XX_EN_GPIOS_MASK | OMAP24XX_EN_GPT1_MASK,
 245                                 WKUP_MOD, PM_WKEN);
 246
 247         /* Enable SYS_CLKEN control when all domains idle */
 248         omap2_prm_set_mod_reg_bits(OMAP_AUTOEXTCLKMODE_MASK, OMAP24XX_GR_MOD,
 249                                    OMAP2_PRCM_CLKSRC_CTRL_OFFSET);
 250 }
 251
 252 int __init omap2_pm_init(void)
 253 {
 254         u32 l;
 255
 256         printk(KERN_INFO "Power Management for OMAP2 initializing\n");
 257         l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_REVISION_OFFSET);
 258         printk(KERN_INFO "PRCM revision %d.%d\n", (l >> 4) & 0x0f, l & 0x0f);
 259
 260         /* Look up important powerdomains */
 261
 262         mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
 263         if (!mpu_pwrdm)
 264                 pr_err("PM: mpu_pwrdm not found\n");
 265
 266         core_pwrdm = pwrdm_lookup("core_pwrdm");
 267         if (!core_pwrdm)
 268                 pr_err("PM: core_pwrdm not found\n");
 269
 270         /* Look up important clockdomains */
 271
 272         mpu_clkdm = clkdm_lookup("mpu_clkdm");
 273         if (!mpu_clkdm)
 274                 pr_err("PM: mpu_clkdm not found\n");
 275
 276         wkup_clkdm = clkdm_lookup("wkup_clkdm");
 277         if (!wkup_clkdm)
 278                 pr_err("PM: wkup_clkdm not found\n");
 279
 280         dsp_clkdm = clkdm_lookup("dsp_clkdm");
 281         if (!dsp_clkdm)
 282                 pr_err("PM: dsp_clkdm not found\n");
 283
 284         gfx_clkdm = clkdm_lookup("gfx_clkdm");
 285         if (!gfx_clkdm)
 286                 pr_err("PM: gfx_clkdm not found\n");
 287
 288
 289         osc_ck = clk_get(NULL, "osc_ck");
 290         if (IS_ERR(osc_ck)) {
 291                 printk(KERN_ERR "could not get osc_ck\n");
 292                 return -ENODEV;
 293         }
 294
 295         if (cpu_is_omap242x()) {
 296                 emul_ck = clk_get(NULL, "emul_ck");
 297                 if (IS_ERR(emul_ck)) {
 298                         printk(KERN_ERR "could not get emul_ck\n");
 299                         clk_put(osc_ck);
 300                         return -ENODEV;
 301                 }
 302         }
 303
 304         prcm_setup_regs();
 305
 306         /*
 307          * We copy the assembler sleep/wakeup routines to SRAM.
 308          * These routines need to be in SRAM as that's the only
 309          * memory the MPU can see when it wakes up after the entire
 310          * chip enters idle.
 311          */
 312         omap2_sram_suspend = omap_sram_push(omap24xx_cpu_suspend,
 313                                             omap24xx_cpu_suspend_sz);
 314
 315         arm_pm_idle = omap2_pm_idle;
 316
 317         return 0;
 318 }