diff options
Diffstat (limited to 'arch/arm/mach-omap2/sleep43xx.S')
-rw-r--r-- | arch/arm/mach-omap2/sleep43xx.S | 488 |
1 files changed, 488 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/sleep43xx.S b/arch/arm/mach-omap2/sleep43xx.S new file mode 100644 index 000000000..5b9343b58 --- /dev/null +++ b/arch/arm/mach-omap2/sleep43xx.S @@ -0,0 +1,488 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Low level suspend code for AM43XX SoCs + * + * Copyright (C) 2013-2018 Texas Instruments Incorporated - http://www.ti.com/ + * Dave Gerlach, Vaibhav Bedia + */ + +#include <generated/ti-pm-asm-offsets.h> +#include <linux/linkage.h> +#include <linux/ti-emif-sram.h> +#include <linux/platform_data/pm33xx.h> +#include <asm/assembler.h> +#include <asm/hardware/cache-l2x0.h> +#include <asm/memory.h> + +#include "cm33xx.h" +#include "common.h" +#include "iomap.h" +#include "omap-secure.h" +#include "omap44xx.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 + .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] + +#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 |