omap4430 power management hardware

1) device power management introduction

   three levels of resource management:

   clock, power, and valtage

 

clock:

   a) interface clock _ICLK

   b) function clock  _FCLK

 

2) module-level clock management

 

|--master satandby protocol:CM___CLKCTRL[x].STBYST

|--slave standby protocol:  Cm___CLKCTRL[x].IDLEST

 

3) module wake-up request:

 

   slave module --> wake-up request --> PRCM

   

   PRCM --> activates the module clocks and acknowledges the module wake-up request.

 

4) clock domain

 

   CM__CLKSTCTRl[x] CLKACTIVITY_

 

   clock domain state transitions

   CM__CLKSTCTRL[x] CLKTRCTRL

 

5) Clock domain HW_ATTO Mode sequences

主要数据结构：

struct power_state {
    struct powerdomain *pwrdm;
    u32 next_state;
#ifdef CONFIG_SUSPEND
    u32 saved_state;
    u32 saved_logic_state;
#endif
    struct list_head node;
};

pwrst_list 构建：

static int __init omap4_pm_init(void)
{
    int ret;
    int ram_addr;

    if (!cpu_is_omap44xx())
        return -ENODEV;

    /*
     * Keep volt/device off disabled by default
     * on 446x.
     */
    if (cpu_is_omap446x())
        volt_off_mode = 0;
    else
        volt_off_mode = 1;

    enable_off_mode = 0;

    pr_err("Power Management for TI OMAP4.\n");
    mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
    cpu0_pwrdm = pwrdm_lookup("cpu0_pwrdm");
    cpu1_pwrdm = pwrdm_lookup("cpu1_pwrdm");
    core_pwrdm = pwrdm_lookup("core_pwrdm");
    per_pwrdm = pwrdm_lookup("l4per_pwrdm");


#ifdef CONFIG_PM
    prcm_setup_regs();
    prcm_clear_statdep_regs();

    ret = request_irq(OMAP44XX_IRQ_PRCM,
              (irq_handler_t)prcm_interrupt_handler,
              IRQF_DISABLED, "prcm", NULL);
    if (ret) {
        printk(KERN_ERR "request_irq failed to register for 0x%x\n",
               OMAP44XX_IRQ_PRCM);
        goto err2;
    }

    so_ram_address = (void *)dma_alloc_so_coherent(NULL, 1024,
            (dma_addr_t *)&ram_addr, GFP_KERNEL);

    if (!so_ram_address) {
        printk ("omap4_pm_init: failed to allocate SO mem.\n");
        return -ENOMEM;
    }

    ret = pwrdm_for_each(pwrdms_setup, NULL); //对于每个power domain 创建power stat
    if (ret) {
        pr_err("Failed to setup powerdomains\n");
        goto err2;
    }

    mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
    if (!mpu_pwrdm) {
        printk(KERN_ERR "Failed to get lookup for MPU pwrdm's\n");
        goto err2;
    }

    (void) clkdm_for_each(clkdms_setup, NULL);

    /* Get handles for VDD's for enabling/disabling SR */
    vdd_mpu = omap_voltage_domain_get("mpu");
    if (IS_ERR(vdd_mpu)) {
        printk(KERN_ERR "Failed to get handle for VDD MPU\n");
        goto err2;
    }

    vdd_iva = omap_voltage_domain_get("iva");
    if (IS_ERR(vdd_iva)) {
        printk(KERN_ERR "Failed to get handle for VDD IVA\n");
        goto err2;
    }

    vdd_core = omap_voltage_domain_get("core");
    if (IS_ERR(vdd_core)) {
        printk(KERN_ERR "Failed to get handle for VDD CORE\n");
        goto err2;
    }

    omap4_mpuss_init();
    omap4_pm_off_mode_enable(enable_off_mode);
#endif

#ifdef CONFIG_SUSPEND
    suspend_set_ops(&omap_pm_ops);
#endif /* CONFIG_SUSPEND */

    omap4_idle_init();
    omap4_trigger_ioctrl();

err2:
    return ret;
}

static int __init pwrdms_setup(struct powerdomain *pwrdm, void *unused)
{
    struct power_state *pwrst;

    if (!pwrdm->pwrsts)
        return 0;

    pwrst = kmalloc(sizeof(struct power_state), GFP_ATOMIC);
    if (!pwrst)
        return -ENOMEM;
    pwrst->pwrdm = pwrdm;
    if ((!strcmp(pwrdm->name, mpu_pwrdm->name)) ||
            (!strcmp(pwrdm->name, core_pwrdm->name)) ||
            (!strcmp(pwrdm->name, cpu0_pwrdm->name)) ||
            (!strcmp(pwrdm->name, cpu1_pwrdm->name)))
        pwrst->next_state = PWRDM_POWER_ON;  //
    else
        pwrst->next_state = PWRDM_POWER_RET;
    list_add(&pwrst->node, &pwrst_list);
     /* 核心的power domain 的电源状态设置为 PWRDM_POWER_ON， 其他的设置成 PWRDM_POWER_RET × /

    return omap4_set_pwrdm_state(pwrst->pwrdm, pwrst->next_state);
}

1.  omap4 power domain  的定义

   static struct powerdomain *powerdomains_omap[] __initdata = {
   
   #if defined(CONFIG_ARCH_OMAP2) || defined(CONFIG_ARCH_OMAP3)
   &wkup_omap2_pwrdm,
   &gfx_omap2_pwrdm,
   #endif
   
   #ifdef CONFIG_ARCH_OMAP2
   &dsp_pwrdm,
   &mpu_24xx_pwrdm,
   &core_24xx_pwrdm,
   #endif
   
   #ifdef CONFIG_ARCH_OMAP2430
   &mdm_pwrdm,
   #endif
   
   #ifdef CONFIG_ARCH_OMAP3
   &iva2_pwrdm,
   &mpu_3xxx_pwrdm,
   &neon_pwrdm,
   &core_3xxx_pre_es3_1_pwrdm,
   &core_3xxx_es3_1_pwrdm,
   &cam_pwrdm,
   &dss_pwrdm,
   &per_pwrdm,
   &emu_pwrdm,
   &sgx_pwrdm,
   &usbhost_pwrdm,
   &dpll1_pwrdm,
   &dpll2_pwrdm,
   &dpll3_pwrdm,
   &dpll4_pwrdm,
   &dpll5_pwrdm,
   #endif
   
   #ifdef CONFIG_ARCH_OMAP4
   &core_44xx_pwrdm,
   &gfx_44xx_pwrdm,
   &abe_44xx_pwrdm,
   &dss_44xx_pwrdm,
   &tesla_44xx_pwrdm,
   &wkup_44xx_pwrdm,
   &cpu0_44xx_pwrdm,
   &cpu1_44xx_pwrdm,
   &emu_44xx_pwrdm,
   &mpu_443x_pwrdm,
   &mpu_446x_pwrdm,
   &ivahd_44xx_pwrdm,
   &cam_44xx_pwrdm,
   &l3init_44xx_pwrdm,
   &l4per_44xx_pwrdm,
   &always_on_core_44xx_pwrdm,
   &cefuse_44xx_pwrdm,
   #endif
   NULL
   };

   power domain list  的构建：

   static void __init omap_4430sdp_init_irq(void) 调用

void __init omap2_init_common_hw(struct omap_sdrc_params *sdrc_cs0,

struct omap_sdrc_params *sdrc_cs1)

调用

pwrdm_init(powerdomains_omap, &omap4_pwrdm_functions);

void pwrdm_init(struct powerdomain **pwrdm_list, struct pwrdm_functions * custom_funcs)
{
    struct powerdomain **p = NULL;

    /*Initialise the global latency constraint mutex */
    mutex_init(&global_wakeuplat_mutex);

    if (!custom_funcs) {
        printk(KERN_ERR "No custom pwrdm functions registered\n");
        BUG();
    }

    arch_pwrdm = custom_funcs;

    if (pwrdm_list) {
        for (p = pwrdm_list; *p; p++)
            _pwrdm_register(*p);  //这个函数将把list  建起了
    }
}