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_fclks_active(void)
  66 {
  67         u32 f1, f2;
  68
  69         f1 = omap2_cm_read_mod_reg(CORE_MOD, CM_FCLKEN1);
  70         f2 = omap2_cm_read_mod_reg(CORE_MOD, OMAP24XX_CM_FCLKEN2);
  71
  72         return (f1 | f2) ? 1 : 0;
  73 }
  74
  75 static int omap2_enter_full_retention(void)
  76 {
  77         u32 l;
  78
  79         /* There is 1 reference hold for all children of the oscillator
  80          * clock, the following will remove it. If no one else uses the
  81          * oscillator itself it will be disabled if/when we enter retention
  82          * mode.
  83          */
  84         clk_disable(osc_ck);
  85
  86         /* Clear old wake-up events */
  87         /* REVISIT: These write to reserved bits? */
  88         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
  89         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
  90         omap2_prm_write_mod_reg(0xffffffff, WKUP_MOD, PM_WKST);
  91
  92         pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_RET);
  93         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
  94
  95         /* Workaround to kill USB */
  96         l = omap_ctrl_readl(OMAP2_CONTROL_DEVCONF0) | OMAP24XX_USBSTANDBYCTRL;
  97         omap_ctrl_writel(l, OMAP2_CONTROL_DEVCONF0);
  98
  99         omap2_gpio_prepare_for_idle(0);
 100
 101         /* One last check for pending IRQs to avoid extra latency due
 102          * to sleeping unnecessarily. */
 103         if (omap_irq_pending())
 104                 goto no_sleep;
 105
 106         /* Jump to SRAM suspend code */
 107         omap2_sram_suspend(sdrc_read_reg(SDRC_DLLA_CTRL),
 108                            OMAP_SDRC_REGADDR(SDRC_DLLA_CTRL),
 109                            OMAP_SDRC_REGADDR(SDRC_POWER));
 110
 111 no_sleep:
 112         omap2_gpio_resume_after_idle();
 113
 114         clk_enable(osc_ck);
 115
 116         /* clear CORE wake-up events */
 117         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
 118         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
 119
 120         /* wakeup domain events - bit 1: GPT1, bit5 GPIO */
 121         omap2_prm_clear_mod_reg_bits(0x4 | 0x1, WKUP_MOD, PM_WKST);
 122
 123         /* MPU domain wake events */
 124         l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 125         if (l & 0x01)
 126                 omap2_prm_write_mod_reg(0x01, OCP_MOD,
 127                                   OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 128         if (l & 0x20)
 129                 omap2_prm_write_mod_reg(0x20, OCP_MOD,
 130                                   OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 131
 132         /* Mask future PRCM-to-MPU interrupts */
 133         omap2_prm_write_mod_reg(0x0, OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
 134
 135         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
 136         pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_ON);
 137
 138         return 0;
 139 }
 140
 141 static int sti_console_enabled;
 142
 143 static int omap2_allow_mpu_retention(void)
 144 {
 145         u32 l;
 146
 147         /* Check for MMC, UART2, UART1, McSPI2, McSPI1 and DSS1. */
 148         l = omap2_cm_read_mod_reg(CORE_MOD, CM_FCLKEN1);
 149         if (l & (OMAP2420_EN_MMC_MASK | OMAP24XX_EN_UART2_MASK |
 150                  OMAP24XX_EN_UART1_MASK | OMAP24XX_EN_MCSPI2_MASK |
 151                  OMAP24XX_EN_MCSPI1_MASK | OMAP24XX_EN_DSS1_MASK))
 152                 return 0;
 153         /* Check for UART3. */
 154         l = omap2_cm_read_mod_reg(CORE_MOD, OMAP24XX_CM_FCLKEN2);
 155         if (l & OMAP24XX_EN_UART3_MASK)
 156                 return 0;
 157         if (sti_console_enabled)
 158                 return 0;
 159
 160         return 1;
 161 }
 162
 163 static void omap2_enter_mpu_retention(void)
 164 {
 165         const int zero = 0;
 166
 167         /* The peripherals seem not to be able to wake up the MPU when
 168          * it is in retention mode. */
 169         if (omap2_allow_mpu_retention()) {
 170                 /* REVISIT: These write to reserved bits? */
 171                 omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
 172                 omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
 173                 omap2_prm_write_mod_reg(0xffffffff, WKUP_MOD, PM_WKST);
 174
 175                 /* Try to enter MPU retention */
 176                 pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
 177
 178         } else {
 179                 /* Block MPU retention */
 180                 pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
 181         }
 182
 183         /* WFI */
 184         asm("mcr p15, 0, %0, c7, c0, 4" : : "r" (zero) : "memory", "cc");
 185
 186         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
 187 }
 188
 189 static int omap2_can_sleep(void)
 190 {
 191         if (omap2_fclks_active())
 192                 return 0;
 193         if (__clk_is_enabled(osc_ck))
 194                 return 0;
 195         if (omap_dma_running())
 196                 return 0;
 197
 198         return 1;
 199 }
 200
 201 static void omap2_pm_idle(void)
 202 {
 203         local_fiq_disable();
 204
 205         if (!omap2_can_sleep()) {
 206                 if (omap_irq_pending())
 207                         goto out;
 208                 omap2_enter_mpu_retention();
 209                 goto out;
 210         }
 211
 212         if (omap_irq_pending())
 213                 goto out;
 214
 215         omap2_enter_full_retention();
 216
 217 out:
 218         local_fiq_enable();
 219 }
 220
 221 static void __init prcm_setup_regs(void)
 222 {
 223         int i, num_mem_banks;
 224         struct powerdomain *pwrdm;
 225
 226         /*
 227          * Enable autoidle
 228          * XXX This should be handled by hwmod code or PRCM init code
 229          */
 230         omap2_prm_write_mod_reg(OMAP24XX_AUTOIDLE_MASK, OCP_MOD,
 231                           OMAP2_PRCM_SYSCONFIG_OFFSET);
 232
 233         /*
 234          * Set CORE powerdomain memory banks to retain their contents
 235          * during RETENTION
 236          */
 237         num_mem_banks = pwrdm_get_mem_bank_count(core_pwrdm);
 238         for (i = 0; i < num_mem_banks; i++)
 239                 pwrdm_set_mem_retst(core_pwrdm, i, PWRDM_POWER_RET);
 240
 241         pwrdm_set_logic_retst(core_pwrdm, PWRDM_POWER_RET);
 242
 243         pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
 244
 245         /* Force-power down DSP, GFX powerdomains */
 246
 247         pwrdm = clkdm_get_pwrdm(dsp_clkdm);
 248         pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
 249
 250         pwrdm = clkdm_get_pwrdm(gfx_clkdm);
 251         pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
 252
 253         /* Enable hardware-supervised idle for all clkdms */
 254         clkdm_for_each(omap_pm_clkdms_setup, NULL);
 255         clkdm_add_wkdep(mpu_clkdm, wkup_clkdm);
 256
 257 #ifdef CONFIG_SUSPEND
 258         omap_pm_suspend = omap2_enter_full_retention;
 259 #endif
 260
 261         /* REVISIT: Configure number of 32 kHz clock cycles for sys_clk
 262          * stabilisation */
 263         omap2_prm_write_mod_reg(15 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
 264                                 OMAP2_PRCM_CLKSSETUP_OFFSET);
 265
 266         /* Configure automatic voltage transition */
 267         omap2_prm_write_mod_reg(2 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
 268                                 OMAP2_PRCM_VOLTSETUP_OFFSET);
 269         omap2_prm_write_mod_reg(OMAP24XX_AUTO_EXTVOLT_MASK |
 270                                 (0x1 << OMAP24XX_SETOFF_LEVEL_SHIFT) |
 271                                 OMAP24XX_MEMRETCTRL_MASK |
 272                                 (0x1 << OMAP24XX_SETRET_LEVEL_SHIFT) |
 273                                 (0x0 << OMAP24XX_VOLT_LEVEL_SHIFT),
 274                                 OMAP24XX_GR_MOD, OMAP2_PRCM_VOLTCTRL_OFFSET);
 275
 276         /* Enable wake-up events */
 277         omap2_prm_write_mod_reg(OMAP24XX_EN_GPIOS_MASK | OMAP24XX_EN_GPT1_MASK,
 278                                 WKUP_MOD, PM_WKEN);
 279 }
 280
 281 int __init omap2_pm_init(void)
 282 {
 283         u32 l;
 284
 285         printk(KERN_INFO "Power Management for OMAP2 initializing\n");
 286         l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_REVISION_OFFSET);
 287         printk(KERN_INFO "PRCM revision %d.%d\n", (l >> 4) & 0x0f, l & 0x0f);
 288
 289         /* Look up important powerdomains */
 290
 291         mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
 292         if (!mpu_pwrdm)
 293                 pr_err("PM: mpu_pwrdm not found\n");
 294
 295         core_pwrdm = pwrdm_lookup("core_pwrdm");
 296         if (!core_pwrdm)
 297                 pr_err("PM: core_pwrdm not found\n");
 298
 299         /* Look up important clockdomains */
 300
 301         mpu_clkdm = clkdm_lookup("mpu_clkdm");
 302         if (!mpu_clkdm)
 303                 pr_err("PM: mpu_clkdm not found\n");
 304
 305         wkup_clkdm = clkdm_lookup("wkup_clkdm");
 306         if (!wkup_clkdm)
 307                 pr_err("PM: wkup_clkdm not found\n");
 308
 309         dsp_clkdm = clkdm_lookup("dsp_clkdm");
 310         if (!dsp_clkdm)
 311                 pr_err("PM: dsp_clkdm not found\n");
 312
 313         gfx_clkdm = clkdm_lookup("gfx_clkdm");
 314         if (!gfx_clkdm)
 315                 pr_err("PM: gfx_clkdm not found\n");
 316
 317
 318         osc_ck = clk_get(NULL, "osc_ck");
 319         if (IS_ERR(osc_ck)) {
 320                 printk(KERN_ERR "could not get osc_ck\n");
 321                 return -ENODEV;
 322         }
 323
 324         if (cpu_is_omap242x()) {
 325                 emul_ck = clk_get(NULL, "emul_ck");
 326                 if (IS_ERR(emul_ck)) {
 327                         printk(KERN_ERR "could not get emul_ck\n");
 328                         clk_put(osc_ck);
 329                         return -ENODEV;
 330                 }
 331         }
 332
 333         prcm_setup_regs();
 334
 335         /*
 336          * We copy the assembler sleep/wakeup routines to SRAM.
 337          * These routines need to be in SRAM as that's the only
 338          * memory the MPU can see when it wakes up after the entire
 339          * chip enters idle.
 340          */
 341         omap2_sram_suspend = omap_sram_push(omap24xx_cpu_suspend,
 342                                             omap24xx_cpu_suspend_sz);
 343
 344         arm_pm_idle = omap2_pm_idle;
 345
 346         return 0;
 347 }