blob: 61f31e591a15735d582eeafc8313406331cf8bda [file] [log] [blame]
/*
* Copyright (c) 2014-2023, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <asm_macros.S>
#include <assert_macros.S>
#include <lib/psci/psci.h>
#include <platform_def.h>
.globl psci_do_pwrdown_cache_maintenance
.globl psci_do_pwrup_cache_maintenance
.globl psci_power_down_wfi
/* -----------------------------------------------------------------------
* void psci_do_pwrdown_cache_maintenance(unsigned int power level);
*
* This function performs cache maintenance for the specified power
* level. The levels of cache affected are determined by the power
* level which is passed as the argument i.e. level 0 results
* in a flush of the L1 cache. Both the L1 and L2 caches are flushed
* for a higher power level.
*
* Additionally, this function also ensures that stack memory is correctly
* flushed out to avoid coherency issues due to a change in its memory
* attributes after the data cache is disabled.
* -----------------------------------------------------------------------
*/
func psci_do_pwrdown_cache_maintenance
stp x29, x30, [sp,#-16]!
stp x19, x20, [sp,#-16]!
/* ---------------------------------------------
* Invoke CPU-specific power down operations for
* the appropriate level
* ---------------------------------------------
*/
bl prepare_cpu_pwr_dwn
/* ---------------------------------------------
* Do stack maintenance by flushing the used
* stack to the main memory and invalidating the
* remainder.
* ---------------------------------------------
*/
bl plat_get_my_stack
/* ---------------------------------------------
* Calculate and store the size of the used
* stack memory in x1.
* ---------------------------------------------
*/
mov x19, x0
mov x1, sp
sub x1, x0, x1
mov x0, sp
bl flush_dcache_range
/* ---------------------------------------------
* Calculate and store the size of the unused
* stack memory in x1. Calculate and store the
* stack base address in x0.
* ---------------------------------------------
*/
sub x0, x19, #PLATFORM_STACK_SIZE
sub x1, sp, x0
bl inv_dcache_range
ldp x19, x20, [sp], #16
ldp x29, x30, [sp], #16
ret
endfunc psci_do_pwrdown_cache_maintenance
/* -----------------------------------------------------------------------
* void psci_do_pwrup_cache_maintenance(void);
*
* This function performs cache maintenance after this cpu is powered up.
* Currently, this involves managing the used stack memory before turning
* on the data cache.
* -----------------------------------------------------------------------
*/
func psci_do_pwrup_cache_maintenance
stp x29, x30, [sp,#-16]!
/* ---------------------------------------------
* Ensure any inflight stack writes have made it
* to main memory.
* ---------------------------------------------
*/
dmb st
/* ---------------------------------------------
* Calculate and store the size of the used
* stack memory in x1. Calculate and store the
* stack base address in x0.
* ---------------------------------------------
*/
bl plat_get_my_stack
mov x1, sp
sub x1, x0, x1
mov x0, sp
bl inv_dcache_range
/* ---------------------------------------------
* Enable the data cache.
* ---------------------------------------------
*/
mrs x0, sctlr_el3
orr x0, x0, #SCTLR_C_BIT
msr sctlr_el3, x0
isb
ldp x29, x30, [sp], #16
ret
endfunc psci_do_pwrup_cache_maintenance
/* -----------------------------------------------------------------------
* void psci_power_down_wfi(void);
* This function is called to indicate to the power controller that it
* is safe to power down this cpu. It should not exit the wfi and will
* be released from reset upon power up.
* -----------------------------------------------------------------------
*/
func psci_power_down_wfi
#if ERRATA_A510_2684597
bl apply_cpu_pwr_dwn_errata
#endif
dsb sy // ensure write buffer empty
1:
wfi
b 1b
endfunc psci_power_down_wfi