/* SPDX-License-Identifier: GPL-2.0 */ /* * Low level suspend code for AM43XX SoCs * * Copyright (C) 2013-2018 Texas Instruments Incorporated - https://www.ti.com/ * Dave Gerlach, Vaibhav Bedia */ #include #include #include #include #include #include #include "cm33xx.h" #include "common.h" #include "iomap.h" #include "omap-secure.h" #include "omap44xx.h" #include "pm-asm-offsets.h" #include "prm33xx.h" #include "prcm43xx.h" /* replicated define because linux/bitops.h cannot be included in assembly */ #define BIT(nr) (1 << (nr)) #define AM33XX_CM_CLKCTRL_MODULESTATE_DISABLED 0x00030000 #define AM33XX_CM_CLKCTRL_MODULEMODE_DISABLE 0x0003 #define AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE 0x0002 #define AM43XX_EMIF_POWEROFF_ENABLE 0x1 #define AM43XX_EMIF_POWEROFF_DISABLE 0x0 #define AM43XX_CM_CLKSTCTRL_CLKTRCTRL_SW_SLEEP 0x1 #define AM43XX_CM_CLKSTCTRL_CLKTRCTRL_HW_AUTO 0x3 #define AM43XX_CM_BASE 0x44DF0000 #define AM43XX_CM_REGADDR(inst, reg) \ AM33XX_L4_WK_IO_ADDRESS(AM43XX_CM_BASE + (inst) + (reg)) #define AM43XX_CM_MPU_CLKSTCTRL AM43XX_CM_REGADDR(AM43XX_CM_MPU_INST, \ AM43XX_CM_MPU_MPU_CDOFFS) #define AM43XX_CM_MPU_MPU_CLKCTRL AM43XX_CM_REGADDR(AM43XX_CM_MPU_INST, \ AM43XX_CM_MPU_MPU_CLKCTRL_OFFSET) #define AM43XX_CM_PER_EMIF_CLKCTRL AM43XX_CM_REGADDR(AM43XX_CM_PER_INST, \ AM43XX_CM_PER_EMIF_CLKCTRL_OFFSET) #define AM43XX_PRM_EMIF_CTRL_OFFSET 0x0030 #define RTC_SECONDS_REG 0x0 #define RTC_PMIC_REG 0x98 #define RTC_PMIC_POWER_EN BIT(16) #define RTC_PMIC_EXT_WAKEUP_STS BIT(12) #define RTC_PMIC_EXT_WAKEUP_POL BIT(4) #define RTC_PMIC_EXT_WAKEUP_EN BIT(0) .arm .arch armv7-a .arch_extension sec .align 3 ENTRY(am43xx_do_wfi) stmfd sp!, {r4 - r11, lr} @ save registers on stack /* Save wfi_flags arg to data space */ mov r4, r0 adr r3, am43xx_pm_ro_sram_data ldr r2, [r3, #AMX3_PM_RO_SRAM_DATA_VIRT_OFFSET] str r4, [r2, #AMX3_PM_WFI_FLAGS_OFFSET] #ifdef CONFIG_CACHE_L2X0 /* Retrieve l2 cache virt address BEFORE we shut off EMIF */ ldr r1, get_l2cache_base blx r1 mov r8, r0 #endif /* Only flush cache is we know we are losing MPU context */ tst r4, #WFI_FLAG_FLUSH_CACHE beq cache_skip_flush /* * Flush all data from the L1 and L2 data cache before disabling * SCTLR.C bit. */ ldr r1, kernel_flush blx r1 /* * Clear the SCTLR.C bit to prevent further data cache * allocation. Clearing SCTLR.C would make all the data accesses * strongly ordered and would not hit the cache. */ mrc p15, 0, r0, c1, c0, 0 bic r0, r0, #(1 << 2) @ Disable the C bit mcr p15, 0, r0, c1, c0, 0 isb dsb /* * Invalidate L1 and L2 data cache. */ ldr r1, kernel_flush blx r1 #ifdef CONFIG_CACHE_L2X0 /* * Clean and invalidate the L2 cache. */ #ifdef CONFIG_PL310_ERRATA_727915 mov r0, #0x03 mov r12, #OMAP4_MON_L2X0_DBG_CTRL_INDEX dsb smc #0 dsb #endif mov r0, r8 adr r4, am43xx_pm_ro_sram_data ldr r3, [r4, #AMX3_PM_RO_SRAM_DATA_VIRT_OFFSET] mov r2, r0 ldr r0, [r2, #L2X0_AUX_CTRL] str r0, [r3, #AMX3_PM_L2_AUX_CTRL_VAL_OFFSET] ldr r0, [r2, #L310_PREFETCH_CTRL] str r0, [r3, #AMX3_PM_L2_PREFETCH_CTRL_VAL_OFFSET] ldr r0, l2_val str r0, [r2, #L2X0_CLEAN_INV_WAY] wait: ldr r0, [r2, #L2X0_CLEAN_INV_WAY] ldr r1, l2_val ands r0, r0, r1 bne wait #ifdef CONFIG_PL310_ERRATA_727915 mov r0, #0x00 mov r12, #OMAP4_MON_L2X0_DBG_CTRL_INDEX dsb smc #0 dsb #endif l2x_sync: mov r0, r8 mov r2, r0 mov r0, #0x0 str r0, [r2, #L2X0_CACHE_SYNC] sync: ldr r0, [r2, #L2X0_CACHE_SYNC] ands r0, r0, #0x1 bne sync #endif /* Restore wfi_flags */ adr r3, am43xx_pm_ro_sram_data ldr r2, [r3, #AMX3_PM_RO_SRAM_DATA_VIRT_OFFSET] ldr r4, [r2, #AMX3_PM_WFI_FLAGS_OFFSET] cache_skip_flush: /* * If we are trying to enter RTC+DDR mode we must perform * a read from the rtc address space to ensure translation * presence in the TLB to avoid page table walk after DDR * is unavailable. */ tst r4, #WFI_FLAG_RTC_ONLY beq skip_rtc_va_refresh adr r3, am43xx_pm_ro_sram_data ldr r1, [r3, #AMX3_PM_RTC_BASE_VIRT_OFFSET] ldr r0, [r1] skip_rtc_va_refresh: /* Check if we want self refresh */ tst r4, #WFI_FLAG_SELF_REFRESH beq emif_skip_enter_sr adr r9, am43xx_emif_sram_table ldr r3, [r9, #EMIF_PM_ENTER_SR_OFFSET] blx r3 emif_skip_enter_sr: /* Only necessary if PER is losing context */ tst r4, #WFI_FLAG_SAVE_EMIF beq emif_skip_save ldr r3, [r9, #EMIF_PM_SAVE_CONTEXT_OFFSET] blx r3 emif_skip_save: /* Only can disable EMIF if we have entered self refresh */ tst r4, #WFI_FLAG_SELF_REFRESH beq emif_skip_disable /* Disable EMIF */ ldr r1, am43xx_virt_emif_clkctrl ldr r2, [r1] bic r2, r2, #AM33XX_CM_CLKCTRL_MODULEMODE_DISABLE str r2, [r1] wait_emif_disable: ldr r2, [r1] mov r3, #AM33XX_CM_CLKCTRL_MODULESTATE_DISABLED cmp r2, r3 bne wait_emif_disable emif_skip_disable: tst r4, #WFI_FLAG_RTC_ONLY beq skip_rtc_only adr r3, am43xx_pm_ro_sram_data ldr r1, [r3, #AMX3_PM_RTC_BASE_VIRT_OFFSET] ldr r0, [r1, #RTC_PMIC_REG] orr r0, r0, #RTC_PMIC_POWER_EN orr r0, r0, #RTC_PMIC_EXT_WAKEUP_STS orr r0, r0, #RTC_PMIC_EXT_WAKEUP_EN orr r0, r0, #RTC_PMIC_EXT_WAKEUP_POL str r0, [r1, #RTC_PMIC_REG] ldr r0, [r1, #RTC_PMIC_REG] /* Wait for 2 seconds to lose power */ mov r3, #2 ldr r2, [r1, #RTC_SECONDS_REG] rtc_loop: ldr r0, [r1, #RTC_SECONDS_REG] cmp r0, r2 beq rtc_loop mov r2, r0 subs r3, r3, #1 bne rtc_loop b re_enable_emif skip_rtc_only: tst r4, #WFI_FLAG_WAKE_M3 beq wkup_m3_skip /* * For the MPU WFI to be registered as an interrupt * to WKUP_M3, MPU_CLKCTRL.MODULEMODE needs to be set * to DISABLED */ ldr r1, am43xx_virt_mpu_clkctrl ldr r2, [r1] bic r2, r2, #AM33XX_CM_CLKCTRL_MODULEMODE_DISABLE str r2, [r1] /* * Put MPU CLKDM to SW_SLEEP */ ldr r1, am43xx_virt_mpu_clkstctrl mov r2, #AM43XX_CM_CLKSTCTRL_CLKTRCTRL_SW_SLEEP str r2, [r1] wkup_m3_skip: /* * Execute a barrier instruction to ensure that all cache, * TLB and branch predictor maintenance operations issued * have completed. */ dsb dmb /* * Execute a WFI instruction and wait until the * STANDBYWFI output is asserted to indicate that the * CPU is in idle and low power state. CPU can specualatively * prefetch the instructions so add NOPs after WFI. Sixteen * NOPs as per Cortex-A9 pipeline. */ wfi nop nop nop nop nop nop nop nop nop nop nop nop nop nop nop nop /* We come here in case of an abort due to a late interrupt */ ldr r1, am43xx_virt_mpu_clkstctrl mov r2, #AM43XX_CM_CLKSTCTRL_CLKTRCTRL_HW_AUTO str r2, [r1] /* Set MPU_CLKCTRL.MODULEMODE back to ENABLE */ ldr r1, am43xx_virt_mpu_clkctrl mov r2, #AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE str r2, [r1] re_enable_emif: /* Re-enable EMIF */ ldr r1, am43xx_virt_emif_clkctrl mov r2, #AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE str r2, [r1] wait_emif_enable: ldr r3, [r1] cmp r2, r3 bne wait_emif_enable tst r4, #WFI_FLAG_FLUSH_CACHE beq cache_skip_restore /* * Set SCTLR.C bit to allow data cache allocation */ mrc p15, 0, r0, c1, c0, 0 orr r0, r0, #(1 << 2) @ Enable the C bit mcr p15, 0, r0, c1, c0, 0 isb cache_skip_restore: /* Only necessary if PER is losing context */ tst r4, #WFI_FLAG_SELF_REFRESH beq emif_skip_exit_sr_abt adr r9, am43xx_emif_sram_table ldr r1, [r9, #EMIF_PM_ABORT_SR_OFFSET] blx r1 emif_skip_exit_sr_abt: /* Let the suspend code know about the abort */ mov r0, #1 ldmfd sp!, {r4 - r11, pc} @ restore regs and return ENDPROC(am43xx_do_wfi) .align ENTRY(am43xx_resume_offset) .word . - am43xx_do_wfi ENTRY(am43xx_resume_from_deep_sleep) /* Set MPU CLKSTCTRL to HW AUTO so that CPUidle works properly */ ldr r1, am43xx_virt_mpu_clkstctrl mov r2, #AM43XX_CM_CLKSTCTRL_CLKTRCTRL_HW_AUTO str r2, [r1] /* For AM43xx, use EMIF power down until context is restored */ ldr r2, am43xx_phys_emif_poweroff mov r1, #AM43XX_EMIF_POWEROFF_ENABLE str r1, [r2, #0x0] /* Re-enable EMIF */ ldr r1, am43xx_phys_emif_clkctrl mov r2, #AM33XX_CM_CLKCTRL_MODULEMODE_ENABLE str r2, [r1] wait_emif_enable1: ldr r3, [r1] cmp r2, r3 bne wait_emif_enable1 adr r9, am43xx_emif_sram_table ldr r1, [r9, #EMIF_PM_RESTORE_CONTEXT_OFFSET] blx r1 ldr r1, [r9, #EMIF_PM_EXIT_SR_OFFSET] blx r1 ldr r2, am43xx_phys_emif_poweroff mov r1, #AM43XX_EMIF_POWEROFF_DISABLE str r1, [r2, #0x0] ldr r1, [r9, #EMIF_PM_RUN_HW_LEVELING] blx r1 #ifdef CONFIG_CACHE_L2X0 ldr r2, l2_cache_base ldr r0, [r2, #L2X0_CTRL] and r0, #0x0f cmp r0, #1 beq skip_l2en @ Skip if already enabled adr r4, am43xx_pm_ro_sram_data ldr r3, [r4, #AMX3_PM_RO_SRAM_DATA_PHYS_OFFSET] ldr r0, [r3, #AMX3_PM_L2_PREFETCH_CTRL_VAL_OFFSET] ldr r12, l2_smc1 dsb smc #0 dsb set_aux_ctrl: ldr r0, [r3, #AMX3_PM_L2_AUX_CTRL_VAL_OFFSET] ldr r12, l2_smc2 dsb smc #0 dsb /* L2 invalidate on resume */ ldr r0, l2_val ldr r2, l2_cache_base str r0, [r2, #L2X0_INV_WAY] wait2: ldr r0, [r2, #L2X0_INV_WAY] ldr r1, l2_val ands r0, r0, r1 bne wait2 #ifdef CONFIG_PL310_ERRATA_727915 mov r0, #0x00 mov r12, #OMAP4_MON_L2X0_DBG_CTRL_INDEX dsb smc #0 dsb #endif l2x_sync2: ldr r2, l2_cache_base mov r0, #0x0 str r0, [r2, #L2X0_CACHE_SYNC] sync2: ldr r0, [r2, #L2X0_CACHE_SYNC] ands r0, r0, #0x1 bne sync2 mov r0, #0x1 ldr r12, l2_smc3 dsb smc #0 dsb #endif skip_l2en: /* We are back. Branch to the common CPU resume routine */ mov r0, #0 ldr pc, resume_addr ENDPROC(am43xx_resume_from_deep_sleep) /* * Local variables */ .align kernel_flush: .word v7_flush_dcache_all ddr_start: .word PAGE_OFFSET am43xx_phys_emif_poweroff: .word (AM43XX_CM_BASE + AM43XX_PRM_DEVICE_INST + \ AM43XX_PRM_EMIF_CTRL_OFFSET) am43xx_virt_mpu_clkstctrl: .word (AM43XX_CM_MPU_CLKSTCTRL) am43xx_virt_mpu_clkctrl: .word (AM43XX_CM_MPU_MPU_CLKCTRL) am43xx_virt_emif_clkctrl: .word (AM43XX_CM_PER_EMIF_CLKCTRL) am43xx_phys_emif_clkctrl: .word (AM43XX_CM_BASE + AM43XX_CM_PER_INST + \ AM43XX_CM_PER_EMIF_CLKCTRL_OFFSET) #ifdef CONFIG_CACHE_L2X0 /* L2 cache related defines for AM437x */ get_l2cache_base: .word omap4_get_l2cache_base l2_cache_base: .word OMAP44XX_L2CACHE_BASE l2_smc1: .word OMAP4_MON_L2X0_PREFETCH_INDEX l2_smc2: .word OMAP4_MON_L2X0_AUXCTRL_INDEX l2_smc3: .word OMAP4_MON_L2X0_CTRL_INDEX l2_val: .word 0xffff #endif .align 3 /* DDR related defines */ ENTRY(am43xx_emif_sram_table) .space EMIF_PM_FUNCTIONS_SIZE ENTRY(am43xx_pm_sram) .word am43xx_do_wfi .word am43xx_do_wfi_sz .word am43xx_resume_offset .word am43xx_emif_sram_table .word am43xx_pm_ro_sram_data resume_addr: .word cpu_resume - PAGE_OFFSET + 0x80000000 .align 3 ENTRY(am43xx_pm_ro_sram_data) .space AMX3_PM_RO_SRAM_DATA_SIZE ENTRY(am43xx_do_wfi_sz) .word . - am43xx_do_wfi