arch/arm/mach-omap2/pm24xx.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * OMAP2 Power Management Routines
   4  *
   5  * Copyright (C) 2005 Texas Instruments, Inc.
   6  * Copyright (C) 2006-2008 Nokia Corporation
   7  *
   8  * Written by:
   9  * Richard Woodruff <r-woodruff2@ti.com>
  10  * Tony Lindgren
  11  * Juha Yrjola
  12  * Amit Kucheria <amit.kucheria@nokia.com>
  13  * Igor Stoppa <igor.stoppa@nokia.com>
  14  *
  15  * Based on pm.c for omap1
  16  */
  17
  18 #include <linux/cpu_pm.h>
  19 #include <linux/suspend.h>
  20 #include <linux/sched.h>
  21 #include <linux/proc_fs.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/sysfs.h>
  24 #include <linux/module.h>
  25 #include <linux/delay.h>
  26 #include <linux/clk.h>
  27 #include <linux/clk-provider.h>
  28 #include <linux/irq.h>
  29 #include <linux/time.h>
  30
  31 #include <asm/fncpy.h>
  32
  33 #include <asm/mach/time.h>
  34 #include <asm/mach/irq.h>
  35 #include <asm/mach-types.h>
  36 #include <asm/system_misc.h>
  37
  38 #include <linux/omap-dma.h>
  39
  40 #include "soc.h"
  41 #include "common.h"
  42 #include "clock.h"
  43 #include "prm2xxx.h"
  44 #include "prm-regbits-24xx.h"
  45 #include "cm2xxx.h"
  46 #include "cm-regbits-24xx.h"
  47 #include "sdrc.h"
  48 #include "sram.h"
  49 #include "pm.h"
  50 #include "control.h"
  51 #include "powerdomain.h"
  52 #include "clockdomain.h"
  53
  54 static void (*omap2_sram_suspend)(u32 dllctrl, void __iomem *sdrc_dlla_ctrl,
  55                                   void __iomem *sdrc_power);
  56
  57 static struct powerdomain *mpu_pwrdm, *core_pwrdm;
  58 static struct clockdomain *dsp_clkdm, *mpu_clkdm, *wkup_clkdm, *gfx_clkdm;
  59
  60 static struct clk *osc_ck, *emul_ck;
  61
  62 static int omap2_enter_full_retention(void)
  63 {
  64         u32 l;
  65
  66         /* There is 1 reference hold for all children of the oscillator
  67          * clock, the following will remove it. If no one else uses the
  68          * oscillator itself it will be disabled if/when we enter retention
  69          * mode.
  70          */
  71         clk_disable(osc_ck);
  72
  73         /* Clear old wake-up events */
  74         /* REVISIT: These write to reserved bits? */
  75         omap_prm_clear_mod_irqs(CORE_MOD, PM_WKST1, ~0);
  76         omap_prm_clear_mod_irqs(CORE_MOD, OMAP24XX_PM_WKST2, ~0);
  77         omap_prm_clear_mod_irqs(WKUP_MOD, PM_WKST, ~0);
  78
  79         pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_RET);
  80         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
  81
  82         /* Workaround to kill USB */
  83         l = omap_ctrl_readl(OMAP2_CONTROL_DEVCONF0) | OMAP24XX_USBSTANDBYCTRL;
  84         omap_ctrl_writel(l, OMAP2_CONTROL_DEVCONF0);
  85
  86         cpu_cluster_pm_enter();
  87
  88         /* One last check for pending IRQs to avoid extra latency due
  89          * to sleeping unnecessarily. */
  90         if (omap_irq_pending())
  91                 goto no_sleep;
  92
  93         /* Jump to SRAM suspend code */
  94         omap2_sram_suspend(sdrc_read_reg(SDRC_DLLA_CTRL),
  95                            OMAP_SDRC_REGADDR(SDRC_DLLA_CTRL),
  96                            OMAP_SDRC_REGADDR(SDRC_POWER));
  97
  98 no_sleep:
  99         cpu_cluster_pm_exit();
 100
 101         clk_enable(osc_ck);
 102
 103         /* clear CORE wake-up events */
 104         omap_prm_clear_mod_irqs(CORE_MOD, PM_WKST1, ~0);
 105         omap_prm_clear_mod_irqs(CORE_MOD, OMAP24XX_PM_WKST2, ~0);
 106
 107         /* wakeup domain events - bit 1: GPT1, bit5 GPIO */
 108         omap_prm_clear_mod_irqs(WKUP_MOD, PM_WKST, 0x4 | 0x1);
 109
 110         /* MPU domain wake events */
 111         omap_prm_clear_mod_irqs(OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET, 0x1);
 112
 113         omap_prm_clear_mod_irqs(OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET, 0x20);
 114
 115         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
 116         pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_ON);
 117
 118         return 0;
 119 }
 120
 121 static int sti_console_enabled;
 122
 123 static int omap2_allow_mpu_retention(void)
 124 {
 125         if (!omap2xxx_cm_mpu_retention_allowed())
 126                 return 0;
 127         if (sti_console_enabled)
 128                 return 0;
 129
 130         return 1;
 131 }
 132
 133 static void omap2_enter_mpu_retention(void)
 134 {
 135         const int zero = 0;
 136
 137         /* The peripherals seem not to be able to wake up the MPU when
 138          * it is in retention mode. */
 139         if (omap2_allow_mpu_retention()) {
 140                 /* REVISIT: These write to reserved bits? */
 141                 omap_prm_clear_mod_irqs(CORE_MOD, PM_WKST1, ~0);
 142                 omap_prm_clear_mod_irqs(CORE_MOD, OMAP24XX_PM_WKST2, ~0);
 143                 omap_prm_clear_mod_irqs(WKUP_MOD, PM_WKST, ~0);
 144
 145                 /* Try to enter MPU retention */
 146                 pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
 147
 148         } else {
 149                 /* Block MPU retention */
 150                 pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
 151         }
 152
 153         /* WFI */
 154         asm("mcr p15, 0, %0, c7, c0, 4" : : "r" (zero) : "memory", "cc");
 155
 156         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
 157 }
 158
 159 static int omap2_can_sleep(void)
 160 {
 161         if (omap2xxx_cm_fclks_active())
 162                 return 0;
 163         if (__clk_is_enabled(osc_ck))
 164                 return 0;
 165         if (omap_dma_running())
 166                 return 0;
 167
 168         return 1;
 169 }
 170
 171 static void omap2_pm_idle(void)
 172 {
 173         if (!omap2_can_sleep()) {
 174                 if (omap_irq_pending())
 175                         return;
 176                 omap2_enter_mpu_retention();
 177                 return;
 178         }
 179
 180         if (omap_irq_pending())
 181                 return;
 182
 183         omap2_enter_full_retention();
 184 }
 185
 186 static void __init prcm_setup_regs(void)
 187 {
 188         int i, num_mem_banks;
 189         struct powerdomain *pwrdm;
 190
 191         /*
 192          * Enable autoidle
 193          * XXX This should be handled by hwmod code or PRCM init code
 194          */
 195         omap2_prm_write_mod_reg(OMAP24XX_AUTOIDLE_MASK, OCP_MOD,
 196                           OMAP2_PRCM_SYSCONFIG_OFFSET);
 197
 198         /*
 199          * Set CORE powerdomain memory banks to retain their contents
 200          * during RETENTION
 201          */
 202         num_mem_banks = pwrdm_get_mem_bank_count(core_pwrdm);
 203         for (i = 0; i < num_mem_banks; i++)
 204                 pwrdm_set_mem_retst(core_pwrdm, i, PWRDM_POWER_RET);
 205
 206         pwrdm_set_logic_retst(core_pwrdm, PWRDM_POWER_RET);
 207
 208         pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
 209
 210         /* Force-power down DSP, GFX powerdomains */
 211
 212         pwrdm = clkdm_get_pwrdm(dsp_clkdm);
 213         pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
 214
 215         pwrdm = clkdm_get_pwrdm(gfx_clkdm);
 216         pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
 217
 218         /* Enable hardware-supervised idle for all clkdms */
 219         clkdm_for_each(omap_pm_clkdms_setup, NULL);
 220         clkdm_add_wkdep(mpu_clkdm, wkup_clkdm);
 221
 222         omap_common_suspend_init(omap2_enter_full_retention);
 223
 224         /* REVISIT: Configure number of 32 kHz clock cycles for sys_clk
 225          * stabilisation */
 226         omap2_prm_write_mod_reg(15 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
 227                                 OMAP2_PRCM_CLKSSETUP_OFFSET);
 228
 229         /* Configure automatic voltage transition */
 230         omap2_prm_write_mod_reg(2 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
 231                                 OMAP2_PRCM_VOLTSETUP_OFFSET);
 232         omap2_prm_write_mod_reg(OMAP24XX_AUTO_EXTVOLT_MASK |
 233                                 (0x1 << OMAP24XX_SETOFF_LEVEL_SHIFT) |
 234                                 OMAP24XX_MEMRETCTRL_MASK |
 235                                 (0x1 << OMAP24XX_SETRET_LEVEL_SHIFT) |
 236                                 (0x0 << OMAP24XX_VOLT_LEVEL_SHIFT),
 237                                 OMAP24XX_GR_MOD, OMAP2_PRCM_VOLTCTRL_OFFSET);
 238
 239         /* Enable wake-up events */
 240         omap2_prm_write_mod_reg(OMAP24XX_EN_GPIOS_MASK | OMAP24XX_EN_GPT1_MASK,
 241                                 WKUP_MOD, PM_WKEN);
 242
 243         /* Enable SYS_CLKEN control when all domains idle */
 244         omap2_prm_set_mod_reg_bits(OMAP_AUTOEXTCLKMODE_MASK, OMAP24XX_GR_MOD,
 245                                    OMAP2_PRCM_CLKSRC_CTRL_OFFSET);
 246 }
 247
 248 int __init omap2_pm_init(void)
 249 {
 250         u32 l;
 251
 252         printk(KERN_INFO "Power Management for OMAP2 initializing\n");
 253         l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_REVISION_OFFSET);
 254         printk(KERN_INFO "PRCM revision %d.%d\n", (l >> 4) & 0x0f, l & 0x0f);
 255
 256         /* Look up important powerdomains */
 257
 258         mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
 259         if (!mpu_pwrdm)
 260                 pr_err("PM: mpu_pwrdm not found\n");
 261
 262         core_pwrdm = pwrdm_lookup("core_pwrdm");
 263         if (!core_pwrdm)
 264                 pr_err("PM: core_pwrdm not found\n");
 265
 266         /* Look up important clockdomains */
 267
 268         mpu_clkdm = clkdm_lookup("mpu_clkdm");
 269         if (!mpu_clkdm)
 270                 pr_err("PM: mpu_clkdm not found\n");
 271
 272         wkup_clkdm = clkdm_lookup("wkup_clkdm");
 273         if (!wkup_clkdm)
 274                 pr_err("PM: wkup_clkdm not found\n");
 275
 276         dsp_clkdm = clkdm_lookup("dsp_clkdm");
 277         if (!dsp_clkdm)
 278                 pr_err("PM: dsp_clkdm not found\n");
 279
 280         gfx_clkdm = clkdm_lookup("gfx_clkdm");
 281         if (!gfx_clkdm)
 282                 pr_err("PM: gfx_clkdm not found\n");
 283
 284
 285         osc_ck = clk_get(NULL, "osc_ck");
 286         if (IS_ERR(osc_ck)) {
 287                 printk(KERN_ERR "could not get osc_ck\n");
 288                 return -ENODEV;
 289         }
 290
 291         if (cpu_is_omap242x()) {
 292                 emul_ck = clk_get(NULL, "emul_ck");
 293                 if (IS_ERR(emul_ck)) {
 294                         printk(KERN_ERR "could not get emul_ck\n");
 295                         clk_put(osc_ck);
 296                         return -ENODEV;
 297                 }
 298         }
 299
 300         prcm_setup_regs();
 301
 302         /*
 303          * We copy the assembler sleep/wakeup routines to SRAM.
 304          * These routines need to be in SRAM as that's the only
 305          * memory the MPU can see when it wakes up after the entire
 306          * chip enters idle.
 307          */
 308         omap2_sram_suspend = omap_sram_push(omap24xx_cpu_suspend,
 309                                             omap24xx_cpu_suspend_sz);
 310
 311         arm_pm_idle = omap2_pm_idle;
 312
 313         return 0;
 314 }