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-provider.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/fncpy.h>
  35
  36 #include <asm/mach/time.h>
  37 #include <asm/mach/irq.h>
  38 #include <asm/mach-types.h>
  39 #include <asm/system_misc.h>
  40
  41 #include <linux/omap-dma.h>
  42
  43 #include "soc.h"
  44 #include "common.h"
  45 #include "clock.h"
  46 #include "prm2xxx.h"
  47 #include "prm-regbits-24xx.h"
  48 #include "cm2xxx.h"
  49 #include "cm-regbits-24xx.h"
  50 #include "sdrc.h"
  51 #include "sram.h"
  52 #include "pm.h"
  53 #include "control.h"
  54 #include "powerdomain.h"
  55 #include "clockdomain.h"
  56
  57 static void (*omap2_sram_suspend)(u32 dllctrl, void __iomem *sdrc_dlla_ctrl,
  58                                   void __iomem *sdrc_power);
  59
  60 static struct powerdomain *mpu_pwrdm, *core_pwrdm;
  61 static struct clockdomain *dsp_clkdm, *mpu_clkdm, *wkup_clkdm, *gfx_clkdm;
  62
  63 static struct clk *osc_ck, *emul_ck;
  64
  65 static int omap2_enter_full_retention(void)
  66 {
  67         u32 l;
  68
  69         /* There is 1 reference hold for all children of the oscillator
  70          * clock, the following will remove it. If no one else uses the
  71          * oscillator itself it will be disabled if/when we enter retention
  72          * mode.
  73          */
  74         clk_disable(osc_ck);
  75
  76         /* Clear old wake-up events */
  77         /* REVISIT: These write to reserved bits? */
  78         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
  79         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
  80         omap2_prm_write_mod_reg(0xffffffff, WKUP_MOD, PM_WKST);
  81
  82         pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_RET);
  83         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
  84
  85         /* Workaround to kill USB */
  86         l = omap_ctrl_readl(OMAP2_CONTROL_DEVCONF0) | OMAP24XX_USBSTANDBYCTRL;
  87         omap_ctrl_writel(l, OMAP2_CONTROL_DEVCONF0);
  88
  89         omap2_gpio_prepare_for_idle(0);
  90
  91         /* One last check for pending IRQs to avoid extra latency due
  92          * to sleeping unnecessarily. */
  93         if (omap_irq_pending())
  94                 goto no_sleep;
  95
  96         /* Jump to SRAM suspend code */
  97         omap2_sram_suspend(sdrc_read_reg(SDRC_DLLA_CTRL),
  98                            OMAP_SDRC_REGADDR(SDRC_DLLA_CTRL),
  99                            OMAP_SDRC_REGADDR(SDRC_POWER));
 100
 101 no_sleep:
 102         omap2_gpio_resume_after_idle();
 103
 104         clk_enable(osc_ck);
 105
 106         /* clear CORE wake-up events */
 107         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
 108         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
 109
 110         /* wakeup domain events - bit 1: GPT1, bit5 GPIO */
 111         omap2_prm_clear_mod_reg_bits(0x4 | 0x1, WKUP_MOD, PM_WKST);
 112
 113         /* MPU domain wake events */
 114         l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 115         if (l & 0x01)
 116                 omap2_prm_write_mod_reg(0x01, OCP_MOD,
 117                                   OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 118         if (l & 0x20)
 119                 omap2_prm_write_mod_reg(0x20, OCP_MOD,
 120                                   OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 121
 122         /* Mask future PRCM-to-MPU interrupts */
 123         omap2_prm_write_mod_reg(0x0, OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 124
 125         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
 126         pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_ON);
 127
 128         return 0;
 129 }
 130
 131 static int sti_console_enabled;
 132
 133 static int omap2_allow_mpu_retention(void)
 134 {
 135         if (!omap2xxx_cm_mpu_retention_allowed())
 136                 return 0;
 137         if (sti_console_enabled)
 138                 return 0;
 139
 140         return 1;
 141 }
 142
 143 static void omap2_enter_mpu_retention(void)
 144 {
 145         const int zero = 0;
 146
 147         /* The peripherals seem not to be able to wake up the MPU when
 148          * it is in retention mode. */
 149         if (omap2_allow_mpu_retention()) {
 150                 /* REVISIT: These write to reserved bits? */
 151                 omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
 152                 omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
 153                 omap2_prm_write_mod_reg(0xffffffff, WKUP_MOD, PM_WKST);
 154
 155                 /* Try to enter MPU retention */
 156                 pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
 157
 158         } else {
 159                 /* Block MPU retention */
 160                 pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
 161         }
 162
 163         /* WFI */
 164         asm("mcr p15, 0, %0, c7, c0, 4" : : "r" (zero) : "memory", "cc");
 165
 166         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
 167 }
 168
 169 static int omap2_can_sleep(void)
 170 {
 171         if (omap2xxx_cm_fclks_active())
 172                 return 0;
 173         if (__clk_is_enabled(osc_ck))
 174                 return 0;
 175         if (omap_dma_running())
 176                 return 0;
 177
 178         return 1;
 179 }
 180
 181 static void omap2_pm_idle(void)
 182 {
 183         if (!omap2_can_sleep()) {
 184                 if (omap_irq_pending())
 185                         return;
 186                 omap2_enter_mpu_retention();
 187                 return;
 188         }
 189
 190         if (omap_irq_pending())
 191                 return;
 192
 193         omap2_enter_full_retention();
 194 }
 195
 196 static void __init prcm_setup_regs(void)
 197 {
 198         int i, num_mem_banks;
 199         struct powerdomain *pwrdm;
 200
 201         /*
 202          * Enable autoidle
 203          * XXX This should be handled by hwmod code or PRCM init code
 204          */
 205         omap2_prm_write_mod_reg(OMAP24XX_AUTOIDLE_MASK, OCP_MOD,
 206                           OMAP2_PRCM_SYSCONFIG_OFFSET);
 207
 208         /*
 209          * Set CORE powerdomain memory banks to retain their contents
 210          * during RETENTION
 211          */
 212         num_mem_banks = pwrdm_get_mem_bank_count(core_pwrdm);
 213         for (i = 0; i < num_mem_banks; i++)
 214                 pwrdm_set_mem_retst(core_pwrdm, i, PWRDM_POWER_RET);
 215
 216         pwrdm_set_logic_retst(core_pwrdm, PWRDM_POWER_RET);
 217
 218         pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
 219
 220         /* Force-power down DSP, GFX powerdomains */
 221
 222         pwrdm = clkdm_get_pwrdm(dsp_clkdm);
 223         pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
 224
 225         pwrdm = clkdm_get_pwrdm(gfx_clkdm);
 226         pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
 227
 228         /* Enable hardware-supervised idle for all clkdms */
 229         clkdm_for_each(omap_pm_clkdms_setup, NULL);
 230         clkdm_add_wkdep(mpu_clkdm, wkup_clkdm);
 231
 232 #ifdef CONFIG_SUSPEND
 233         omap_pm_suspend = omap2_enter_full_retention;
 234 #endif
 235
 236         /* REVISIT: Configure number of 32 kHz clock cycles for sys_clk
 237          * stabilisation */
 238         omap2_prm_write_mod_reg(15 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
 239                                 OMAP2_PRCM_CLKSSETUP_OFFSET);
 240
 241         /* Configure automatic voltage transition */
 242         omap2_prm_write_mod_reg(2 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
 243                                 OMAP2_PRCM_VOLTSETUP_OFFSET);
 244         omap2_prm_write_mod_reg(OMAP24XX_AUTO_EXTVOLT_MASK |
 245                                 (0x1 << OMAP24XX_SETOFF_LEVEL_SHIFT) |
 246                                 OMAP24XX_MEMRETCTRL_MASK |
 247                                 (0x1 << OMAP24XX_SETRET_LEVEL_SHIFT) |
 248                                 (0x0 << OMAP24XX_VOLT_LEVEL_SHIFT),
 249                                 OMAP24XX_GR_MOD, OMAP2_PRCM_VOLTCTRL_OFFSET);
 250
 251         /* Enable wake-up events */
 252         omap2_prm_write_mod_reg(OMAP24XX_EN_GPIOS_MASK | OMAP24XX_EN_GPT1_MASK,
 253                                 WKUP_MOD, PM_WKEN);
 254 }
 255
 256 int __init omap2_pm_init(void)
 257 {
 258         u32 l;
 259
 260         printk(KERN_INFO "Power Management for OMAP2 initializing\n");
 261         l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_REVISION_OFFSET);
 262         printk(KERN_INFO "PRCM revision %d.%d\n", (l >> 4) & 0x0f, l & 0x0f);
 263
 264         /* Look up important powerdomains */
 265
 266         mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
 267         if (!mpu_pwrdm)
 268                 pr_err("PM: mpu_pwrdm not found\n");
 269
 270         core_pwrdm = pwrdm_lookup("core_pwrdm");
 271         if (!core_pwrdm)
 272                 pr_err("PM: core_pwrdm not found\n");
 273
 274         /* Look up important clockdomains */
 275
 276         mpu_clkdm = clkdm_lookup("mpu_clkdm");
 277         if (!mpu_clkdm)
 278                 pr_err("PM: mpu_clkdm not found\n");
 279
 280         wkup_clkdm = clkdm_lookup("wkup_clkdm");
 281         if (!wkup_clkdm)
 282                 pr_err("PM: wkup_clkdm not found\n");
 283
 284         dsp_clkdm = clkdm_lookup("dsp_clkdm");
 285         if (!dsp_clkdm)
 286                 pr_err("PM: dsp_clkdm not found\n");
 287
 288         gfx_clkdm = clkdm_lookup("gfx_clkdm");
 289         if (!gfx_clkdm)
 290                 pr_err("PM: gfx_clkdm not found\n");
 291
 292
 293         osc_ck = clk_get(NULL, "osc_ck");
 294         if (IS_ERR(osc_ck)) {
 295                 printk(KERN_ERR "could not get osc_ck\n");
 296                 return -ENODEV;
 297         }
 298
 299         if (cpu_is_omap242x()) {
 300                 emul_ck = clk_get(NULL, "emul_ck");
 301                 if (IS_ERR(emul_ck)) {
 302                         printk(KERN_ERR "could not get emul_ck\n");
 303                         clk_put(osc_ck);
 304                         return -ENODEV;
 305                 }
 306         }
 307
 308         prcm_setup_regs();
 309
 310         /*
 311          * We copy the assembler sleep/wakeup routines to SRAM.
 312          * These routines need to be in SRAM as that's the only
 313          * memory the MPU can see when it wakes up after the entire
 314          * chip enters idle.
 315          */
 316         omap2_sram_suspend = omap_sram_push(omap24xx_cpu_suspend,
 317                                             omap24xx_cpu_suspend_sz);
 318
 319         arm_pm_idle = omap2_pm_idle;
 320
 321         return 0;
 322 }