blob: e7d94b509ca7ca29c428dbec0c33863450c72091 [file] [log] [blame]
/*
* Copyright (c) 2013-2018, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <arch.h>
#include <bl_common.h>
#include <el3_common_macros.S>
#include <pmf_asm_macros.S>
#include <runtime_instr.h>
#include <xlat_mmu_helpers.h>
.globl bl31_entrypoint
.globl bl31_warm_entrypoint
/* -----------------------------------------------------
* bl31_entrypoint() is the cold boot entrypoint,
* executed only by the primary cpu.
* -----------------------------------------------------
*/
func bl31_entrypoint
#if !RESET_TO_BL31
/* ---------------------------------------------------------------
* Preceding bootloader has populated x0 with a pointer to a
* 'bl31_params' structure & x1 with a pointer to platform
* specific structure
* ---------------------------------------------------------------
*/
mov x20, x0
mov x21, x1
/* ---------------------------------------------------------------------
* For !RESET_TO_BL31 systems, only the primary CPU ever reaches
* bl31_entrypoint() during the cold boot flow, so the cold/warm boot
* and primary/secondary CPU logic should not be executed in this case.
*
* Also, assume that the previous bootloader has already initialised the
* SCTLR_EL3, including the endianness, and has initialised the memory.
* ---------------------------------------------------------------------
*/
el3_entrypoint_common \
_init_sctlr=0 \
_warm_boot_mailbox=0 \
_secondary_cold_boot=0 \
_init_memory=0 \
_init_c_runtime=1 \
_exception_vectors=runtime_exceptions
/* ---------------------------------------------------------------------
* Relay the previous bootloader's arguments to the platform layer
* ---------------------------------------------------------------------
*/
mov x0, x20
mov x1, x21
#else
/* ---------------------------------------------------------------------
* For RESET_TO_BL31 systems which have a programmable reset address,
* bl31_entrypoint() is executed only on the cold boot path so we can
* skip the warm boot mailbox mechanism.
* ---------------------------------------------------------------------
*/
el3_entrypoint_common \
_init_sctlr=1 \
_warm_boot_mailbox=!PROGRAMMABLE_RESET_ADDRESS \
_secondary_cold_boot=!COLD_BOOT_SINGLE_CPU \
_init_memory=1 \
_init_c_runtime=1 \
_exception_vectors=runtime_exceptions
/* ---------------------------------------------------------------------
* For RESET_TO_BL31 systems, BL31 is the first bootloader to run so
* there's no argument to relay from a previous bootloader. Zero the
* arguments passed to the platform layer to reflect that.
* ---------------------------------------------------------------------
*/
mov x0, 0
mov x1, 0
#endif /* RESET_TO_BL31 */
/* ---------------------------------------------
* Perform platform specific early arch. setup
* ---------------------------------------------
*/
bl bl31_early_platform_setup
bl bl31_plat_arch_setup
/* ---------------------------------------------
* Jump to main function.
* ---------------------------------------------
*/
bl bl31_main
/* -------------------------------------------------------------
* Clean the .data & .bss sections to main memory. This ensures
* that any global data which was initialised by the primary CPU
* is visible to secondary CPUs before they enable their data
* caches and participate in coherency.
* -------------------------------------------------------------
*/
adr x0, __DATA_START__
adr x1, __DATA_END__
sub x1, x1, x0
bl clean_dcache_range
adr x0, __BSS_START__
adr x1, __BSS_END__
sub x1, x1, x0
bl clean_dcache_range
b el3_exit
endfunc bl31_entrypoint
/* --------------------------------------------------------------------
* This CPU has been physically powered up. It is either resuming from
* suspend or has simply been turned on. In both cases, call the BL31
* warmboot entrypoint
* --------------------------------------------------------------------
*/
func bl31_warm_entrypoint
#if ENABLE_RUNTIME_INSTRUMENTATION
/*
* This timestamp update happens with cache off. The next
* timestamp collection will need to do cache maintenance prior
* to timestamp update.
*/
pmf_calc_timestamp_addr rt_instr_svc RT_INSTR_EXIT_HW_LOW_PWR
mrs x1, cntpct_el0
str x1, [x0]
#endif
/*
* On the warm boot path, most of the EL3 initialisations performed by
* 'el3_entrypoint_common' must be skipped:
*
* - Only when the platform bypasses the BL1/BL31 entrypoint by
* programming the reset address do we need to initialise SCTLR_EL3.
* In other cases, we assume this has been taken care by the
* entrypoint code.
*
* - No need to determine the type of boot, we know it is a warm boot.
*
* - Do not try to distinguish between primary and secondary CPUs, this
* notion only exists for a cold boot.
*
* - No need to initialise the memory or the C runtime environment,
* it has been done once and for all on the cold boot path.
*/
el3_entrypoint_common \
_init_sctlr=PROGRAMMABLE_RESET_ADDRESS \
_warm_boot_mailbox=0 \
_secondary_cold_boot=0 \
_init_memory=0 \
_init_c_runtime=0 \
_exception_vectors=runtime_exceptions
/*
* We're about to enable MMU and participate in PSCI state coordination.
*
* The PSCI implementation invokes platform routines that enable CPUs to
* participate in coherency. On a system where CPUs are not
* cache-coherent without appropriate platform specific programming,
* having caches enabled until such time might lead to coherency issues
* (resulting from stale data getting speculatively fetched, among
* others). Therefore we keep data caches disabled even after enabling
* the MMU for such platforms.
*
* On systems with hardware-assisted coherency, or on single cluster
* platforms, such platform specific programming is not required to
* enter coherency (as CPUs already are); and there's no reason to have
* caches disabled either.
*/
mov x0, #DISABLE_DCACHE
bl bl31_plat_enable_mmu
#if HW_ASSISTED_COHERENCY || WARMBOOT_ENABLE_DCACHE_EARLY
mrs x0, sctlr_el3
orr x0, x0, #SCTLR_C_BIT
msr sctlr_el3, x0
isb
#endif
bl psci_warmboot_entrypoint
#if ENABLE_RUNTIME_INSTRUMENTATION
pmf_calc_timestamp_addr rt_instr_svc RT_INSTR_EXIT_PSCI
mov x19, x0
/*
* Invalidate before updating timestamp to ensure previous timestamp
* updates on the same cache line with caches disabled are properly
* seen by the same core. Without the cache invalidate, the core might
* write into a stale cache line.
*/
mov x1, #PMF_TS_SIZE
mov x20, x30
bl inv_dcache_range
mov x30, x20
mrs x0, cntpct_el0
str x0, [x19]
#endif
b el3_exit
endfunc bl31_warm_entrypoint