/* * OMAP MPUSS low power code * * Copyright (C) 2011 Texas Instruments, Inc. * Santosh Shilimkar * * OMAP4430 MPUSS mainly consists of dual Cortex-A9 with per-CPU * Local timer and Watchdog, GIC, SCU, PL310 L2 cache controller, * CPU0 and CPU1 LPRM modules. * CPU0, CPU1 and MPUSS each have there own power domain and * hence multiple low power combinations of MPUSS are possible. * * The CPU0 and CPU1 can't support Closed switch Retention (CSWR) * because the mode is not supported by hw constraints of dormant * mode. While waking up from the dormant mode, a reset signal * to the Cortex-A9 processor must be asserted by the external * power controller. * * With architectural inputs and hardware recommendations, only * below modes are supported from power gain vs latency point of view. * * CPU0 CPU1 MPUSS * ---------------------------------------------- * ON ON ON * ON(Inactive) OFF ON(Inactive) * OFF OFF CSWR * OFF OFF OSWR * OFF OFF OFF(Device OFF *TBD) * ---------------------------------------------- * * Note: CPU0 is the master core and it is the last CPU to go down * and first to wake-up when MPUSS low power states are excercised * * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #include #include #include "soc.h" #include "common.h" #include "omap44xx.h" #include "omap4-sar-layout.h" #include "pm.h" #include "prcm_mpu44xx.h" #include "prcm_mpu54xx.h" #include "prminst44xx.h" #include "prcm44xx.h" #include "prm44xx.h" #include "prm-regbits-44xx.h" #ifdef CONFIG_SMP struct omap4_cpu_pm_info { struct powerdomain *pwrdm; void __iomem *scu_sar_addr; void __iomem *wkup_sar_addr; void __iomem *l2x0_sar_addr; }; /** * struct cpu_pm_ops - CPU pm operations * @finish_suspend: CPU suspend finisher function pointer * @resume: CPU resume function pointer * @scu_prepare: CPU Snoop Control program function pointer * @hotplug_restart: CPU restart function pointer * * Structure holds functions pointer for CPU low power operations like * suspend, resume and scu programming. */ struct cpu_pm_ops { int (*finish_suspend)(unsigned long cpu_state); void (*resume)(void); void (*scu_prepare)(unsigned int cpu_id, unsigned int cpu_state); void (*hotplug_restart)(void); }; static DEFINE_PER_CPU(struct omap4_cpu_pm_info, omap4_pm_info); static struct powerdomain *mpuss_pd; static void __iomem *sar_base; static u32 cpu_context_offset; static int default_finish_suspend(unsigned long cpu_state) { omap_do_wfi(); return 0; } static void dummy_cpu_resume(void) {} static void dummy_scu_prepare(unsigned int cpu_id, unsigned int cpu_state) {} struct cpu_pm_ops omap_pm_ops = { .finish_suspend = default_finish_suspend, .resume = dummy_cpu_resume, .scu_prepare = dummy_scu_prepare, .hotplug_restart = dummy_cpu_resume, }; /* * Program the wakeup routine address for the CPU0 and CPU1 * used for OFF or DORMANT wakeup. */ static inline void set_cpu_wakeup_addr(unsigned int cpu_id, u32 addr) { struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id); if (pm_info->wkup_sar_addr) writel_relaxed(addr, pm_info->wkup_sar_addr); } /* * Store the SCU power status value to scratchpad memory */ static void scu_pwrst_prepare(unsigned int cpu_id, unsigned int cpu_state) { struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id); u32 scu_pwr_st; switch (cpu_state) { case PWRDM_POWER_RET: scu_pwr_st = SCU_PM_DORMANT; break; case PWRDM_POWER_OFF: scu_pwr_st = SCU_PM_POWEROFF; break; case PWRDM_POWER_ON: case PWRDM_POWER_INACTIVE: default: scu_pwr_st = SCU_PM_NORMAL; break; } if (pm_info->scu_sar_addr) writel_relaxed(scu_pwr_st, pm_info->scu_sar_addr); } /* Helper functions for MPUSS OSWR */ static inline void mpuss_clear_prev_logic_pwrst(void) { u32 reg; reg = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION, OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET); omap4_prminst_write_inst_reg(reg, OMAP4430_PRM_PARTITION, OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET); } static inline void cpu_clear_prev_logic_pwrst(unsigned int cpu_id) { u32 reg; if (cpu_id) { reg = omap4_prcm_mpu_read_inst_reg(OMAP4430_PRCM_MPU_CPU1_INST, cpu_context_offset); omap4_prcm_mpu_write_inst_reg(reg, OMAP4430_PRCM_MPU_CPU1_INST, cpu_context_offset); } else { reg = omap4_prcm_mpu_read_inst_reg(OMAP4430_PRCM_MPU_CPU0_INST, cpu_context_offset); omap4_prcm_mpu_write_inst_reg(reg, OMAP4430_PRCM_MPU_CPU0_INST, cpu_context_offset); } } /* * Store the CPU cluster state for L2X0 low power operations. */ static void l2x0_pwrst_prepare(unsigned int cpu_id, unsigned int save_state) { struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id); if (pm_info->l2x0_sar_addr) writel_relaxed(save_state, pm_info->l2x0_sar_addr); } /* * Save the L2X0 AUXCTRL and POR value to SAR memory. Its used to * in every restore MPUSS OFF path. */ #ifdef CONFIG_CACHE_L2X0 static void __init save_l2x0_context(void) { void __iomem *l2x0_base = omap4_get_l2cache_base(); if (l2x0_base && sar_base) { writel_relaxed(l2x0_saved_regs.aux_ctrl, sar_base + L2X0_AUXCTRL_OFFSET); writel_relaxed(l2x0_saved_regs.prefetch_ctrl, sar_base + L2X0_PREFETCH_CTRL_OFFSET); } } #else static void __init save_l2x0_context(void) {} #endif /** * omap4_enter_lowpower: OMAP4 MPUSS Low Power Entry Function * The purpose of this function is to manage low power programming * of OMAP4 MPUSS subsystem * @cpu : CPU ID * @power_state: Low power state. * * MPUSS states for the context save: * save_state = * 0 - Nothing lost and no need to save: MPUSS INACTIVE * 1 - CPUx L1 and logic lost: MPUSS CSWR * 2 - CPUx L1 and logic lost + GIC lost: MPUSS OSWR * 3 - CPUx L1 and logic lost + GIC + L2 lost: DEVICE OFF */ int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state) { struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu); unsigned int save_state = 0, cpu_logic_state = PWRDM_POWER_RET; unsigned int wakeup_cpu; if (omap_rev() == OMAP4430_REV_ES1_0) return -ENXIO; switch (power_state) { case PWRDM_POWER_ON: case PWRDM_POWER_INACTIVE: save_state = 0; break; case PWRDM_POWER_OFF: cpu_logic_state = PWRDM_POWER_OFF; save_state = 1; break; case PWRDM_POWER_RET: if (IS_PM44XX_ERRATUM(PM_OMAP4_CPU_OSWR_DISABLE)) { save_state = 0; break; } default: /* * CPUx CSWR is invalid hardware state. Also CPUx OSWR * doesn't make much scense, since logic is lost and $L1 * needs to be cleaned because of coherency. This makes * CPUx OSWR equivalent to CPUX OFF and hence not supported */ WARN_ON(1); return -ENXIO; } pwrdm_pre_transition(NULL); /* * Check MPUSS next state and save interrupt controller if needed. * In MPUSS OSWR or device OFF, interrupt controller contest is lost. */ mpuss_clear_prev_logic_pwrst(); if ((pwrdm_read_next_pwrst(mpuss_pd) == PWRDM_POWER_RET) && (pwrdm_read_logic_retst(mpuss_pd) == PWRDM_POWER_OFF)) save_state = 2; cpu_clear_prev_logic_pwrst(cpu); pwrdm_set_next_pwrst(pm_info->pwrdm, power_state); pwrdm_set_logic_retst(pm_info->pwrdm, cpu_logic_state); set_cpu_wakeup_addr(cpu, virt_to_phys(omap_pm_ops.resume)); omap_pm_ops.scu_prepare(cpu, power_state); l2x0_pwrst_prepare(cpu, save_state); /* * Call low level function with targeted low power state. */ if (save_state) cpu_suspend(save_state, omap_pm_ops.finish_suspend); else omap_pm_ops.finish_suspend(save_state); if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD) && cpu) gic_dist_enable(); /* * Restore the CPUx power state to ON otherwise CPUx * power domain can transitions to programmed low power * state while doing WFI outside the low powe code. On * secure devices, CPUx does WFI which can result in * domain transition */ wakeup_cpu = smp_processor_id(); pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON); pwrdm_post_transition(NULL); return 0; } /** * omap4_hotplug_cpu: OMAP4 CPU hotplug entry * @cpu : CPU ID * @power_state: CPU low power state. */ int omap4_hotplug_cpu(unsigned int cpu, unsigned int power_state) { struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu); unsigned int cpu_state = 0; if (omap_rev() == OMAP4430_REV_ES1_0) return -ENXIO; /* Use the achievable power state for the domain */ power_state = pwrdm_get_valid_lp_state(pm_info->pwrdm, false, power_state); if (power_state == PWRDM_POWER_OFF) cpu_state = 1; pwrdm_clear_all_prev_pwrst(pm_info->pwrdm); pwrdm_set_next_pwrst(pm_info->pwrdm, power_state); set_cpu_wakeup_addr(cpu, virt_to_phys(omap_pm_ops.hotplug_restart)); omap_pm_ops.scu_prepare(cpu, power_state); /* * CPU never retuns back if targeted power state is OFF mode. * CPU ONLINE follows normal CPU ONLINE ptah via * omap4_secondary_startup(). */ omap_pm_ops.finish_suspend(cpu_state); pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON); return 0; } /* * Enable Mercury Fast HG retention mode by default. */ static void enable_mercury_retention_mode(void) { u32 reg; reg = omap4_prcm_mpu_read_inst_reg(OMAP54XX_PRCM_MPU_DEVICE_INST, OMAP54XX_PRCM_MPU_PRM_PSCON_COUNT_OFFSET); /* Enable HG_EN, HG_RAMPUP = fast mode */ reg |= BIT(24) | BIT(25); omap4_prcm_mpu_write_inst_reg(reg, OMAP54XX_PRCM_MPU_DEVICE_INST, OMAP54XX_PRCM_MPU_PRM_PSCON_COUNT_OFFSET); } /* * Initialise OMAP4 MPUSS */ int __init omap4_mpuss_init(void) { struct omap4_cpu_pm_info *pm_info; if (omap_rev() == OMAP4430_REV_ES1_0) { WARN(1, "Power Management not supported on OMAP4430 ES1.0\n"); return -ENODEV; } if (cpu_is_omap44xx()) sar_base = omap4_get_sar_ram_base(); /* Initilaise per CPU PM information */ pm_info = &per_cpu(omap4_pm_info, 0x0); if (sar_base) { pm_info->scu_sar_addr = sar_base + SCU_OFFSET0; pm_info->wkup_sar_addr = sar_base + CPU0_WAKEUP_NS_PA_ADDR_OFFSET; pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET0; } pm_info->pwrdm = pwrdm_lookup("cpu0_pwrdm"); if (!pm_info->pwrdm) { pr_err("Lookup failed for CPU0 pwrdm\n"); return -ENODEV; } /* Clear CPU previous power domain state */ pwrdm_clear_all_prev_pwrst(pm_info->pwrdm); cpu_clear_prev_logic_pwrst(0); /* Initialise CPU0 power domain state to ON */ pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON); pm_info = &per_cpu(omap4_pm_info, 0x1); if (sar_base) { pm_info->scu_sar_addr = sar_base + SCU_OFFSET1; pm_info->wkup_sar_addr = sar_base + CPU1_WAKEUP_NS_PA_ADDR_OFFSET; pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET1; } pm_info->pwrdm = pwrdm_lookup("cpu1_pwrdm"); if (!pm_info->pwrdm) { pr_err("Lookup failed for CPU1 pwrdm\n"); return -ENODEV; } /* Clear CPU previous power domain state */ pwrdm_clear_all_prev_pwrst(pm_info->pwrdm); cpu_clear_prev_logic_pwrst(1); /* Initialise CPU1 power domain state to ON */ pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON); mpuss_pd = pwrdm_lookup("mpu_pwrdm"); if (!mpuss_pd) { pr_err("Failed to lookup MPUSS power domain\n"); return -ENODEV; } pwrdm_clear_all_prev_pwrst(mpuss_pd); mpuss_clear_prev_logic_pwrst(); if (sar_base) { /* Save device type on scratchpad for low level code to use */ writel_relaxed((omap_type() != OMAP2_DEVICE_TYPE_GP) ? 1 : 0, sar_base + OMAP_TYPE_OFFSET); save_l2x0_context(); } if (cpu_is_omap44xx()) { omap_pm_ops.finish_suspend = omap4_finish_suspend; omap_pm_ops.resume = omap4_cpu_resume; omap_pm_ops.scu_prepare = scu_pwrst_prepare; omap_pm_ops.hotplug_restart = omap4_secondary_startup; cpu_context_offset = OMAP4_RM_CPU0_CPU0_CONTEXT_OFFSET; } else if (soc_is_omap54xx() || soc_is_dra7xx()) { cpu_context_offset = OMAP54XX_RM_CPU0_CPU0_CONTEXT_OFFSET; enable_mercury_retention_mode(); } if (cpu_is_omap446x()) omap_pm_ops.hotplug_restart = omap4460_secondary_startup; return 0; } #endif