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-rw-r--r--lib/el3_runtime/aarch64/context.S1136
1 files changed, 1136 insertions, 0 deletions
diff --git a/lib/el3_runtime/aarch64/context.S b/lib/el3_runtime/aarch64/context.S
new file mode 100644
index 0000000..6b88a90
--- /dev/null
+++ b/lib/el3_runtime/aarch64/context.S
@@ -0,0 +1,1136 @@
+/*
+ * Copyright (c) 2013-2022, Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arch.h>
+#include <asm_macros.S>
+#include <assert_macros.S>
+#include <context.h>
+#include <el3_common_macros.S>
+
+#if CTX_INCLUDE_EL2_REGS
+ .global el2_sysregs_context_save_common
+ .global el2_sysregs_context_restore_common
+#if ENABLE_SPE_FOR_LOWER_ELS
+ .global el2_sysregs_context_save_spe
+ .global el2_sysregs_context_restore_spe
+#endif /* ENABLE_SPE_FOR_LOWER_ELS */
+#if CTX_INCLUDE_MTE_REGS
+ .global el2_sysregs_context_save_mte
+ .global el2_sysregs_context_restore_mte
+#endif /* CTX_INCLUDE_MTE_REGS */
+#if ENABLE_MPAM_FOR_LOWER_ELS
+ .global el2_sysregs_context_save_mpam
+ .global el2_sysregs_context_restore_mpam
+#endif /* ENABLE_MPAM_FOR_LOWER_ELS */
+#if ENABLE_FEAT_FGT
+ .global el2_sysregs_context_save_fgt
+ .global el2_sysregs_context_restore_fgt
+#endif /* ENABLE_FEAT_FGT */
+#if ENABLE_FEAT_ECV
+ .global el2_sysregs_context_save_ecv
+ .global el2_sysregs_context_restore_ecv
+#endif /* ENABLE_FEAT_ECV */
+#if ENABLE_FEAT_VHE
+ .global el2_sysregs_context_save_vhe
+ .global el2_sysregs_context_restore_vhe
+#endif /* ENABLE_FEAT_VHE */
+#if RAS_EXTENSION
+ .global el2_sysregs_context_save_ras
+ .global el2_sysregs_context_restore_ras
+#endif /* RAS_EXTENSION */
+#if CTX_INCLUDE_NEVE_REGS
+ .global el2_sysregs_context_save_nv2
+ .global el2_sysregs_context_restore_nv2
+#endif /* CTX_INCLUDE_NEVE_REGS */
+#if ENABLE_TRF_FOR_NS
+ .global el2_sysregs_context_save_trf
+ .global el2_sysregs_context_restore_trf
+#endif /* ENABLE_TRF_FOR_NS */
+#if ENABLE_FEAT_CSV2_2
+ .global el2_sysregs_context_save_csv2
+ .global el2_sysregs_context_restore_csv2
+#endif /* ENABLE_FEAT_CSV2_2 */
+#if ENABLE_FEAT_HCX
+ .global el2_sysregs_context_save_hcx
+ .global el2_sysregs_context_restore_hcx
+#endif /* ENABLE_FEAT_HCX */
+#endif /* CTX_INCLUDE_EL2_REGS */
+
+ .global el1_sysregs_context_save
+ .global el1_sysregs_context_restore
+#if CTX_INCLUDE_FPREGS
+ .global fpregs_context_save
+ .global fpregs_context_restore
+#endif /* CTX_INCLUDE_FPREGS */
+ .global prepare_el3_entry
+ .global restore_gp_pmcr_pauth_regs
+ .global save_and_update_ptw_el1_sys_regs
+ .global el3_exit
+
+#if CTX_INCLUDE_EL2_REGS
+
+/* -----------------------------------------------------
+ * The following functions strictly follow the AArch64
+ * PCS to use x9-x16 (temporary caller-saved registers)
+ * to save/restore EL2 system register context.
+ * el2_sysregs_context_save/restore_common functions
+ * save and restore registers that are common to all
+ * configurations. The rest of the functions save and
+ * restore EL2 system registers that are present when a
+ * particular feature is enabled. All functions assume
+ * that 'x0' is pointing to a 'el2_sys_regs' structure
+ * where the register context will be saved/restored.
+ *
+ * The following registers are not added.
+ * AMEVCNTVOFF0<n>_EL2
+ * AMEVCNTVOFF1<n>_EL2
+ * ICH_AP0R<n>_EL2
+ * ICH_AP1R<n>_EL2
+ * ICH_LR<n>_EL2
+ * -----------------------------------------------------
+ */
+func el2_sysregs_context_save_common
+ mrs x9, actlr_el2
+ mrs x10, afsr0_el2
+ stp x9, x10, [x0, #CTX_ACTLR_EL2]
+
+ mrs x11, afsr1_el2
+ mrs x12, amair_el2
+ stp x11, x12, [x0, #CTX_AFSR1_EL2]
+
+ mrs x13, cnthctl_el2
+ mrs x14, cntvoff_el2
+ stp x13, x14, [x0, #CTX_CNTHCTL_EL2]
+
+ mrs x15, cptr_el2
+ str x15, [x0, #CTX_CPTR_EL2]
+
+#if CTX_INCLUDE_AARCH32_REGS
+ mrs x16, dbgvcr32_el2
+ str x16, [x0, #CTX_DBGVCR32_EL2]
+#endif /* CTX_INCLUDE_AARCH32_REGS */
+
+ mrs x9, elr_el2
+ mrs x10, esr_el2
+ stp x9, x10, [x0, #CTX_ELR_EL2]
+
+ mrs x11, far_el2
+ mrs x12, hacr_el2
+ stp x11, x12, [x0, #CTX_FAR_EL2]
+
+ mrs x13, hcr_el2
+ mrs x14, hpfar_el2
+ stp x13, x14, [x0, #CTX_HCR_EL2]
+
+ mrs x15, hstr_el2
+ mrs x16, ICC_SRE_EL2
+ stp x15, x16, [x0, #CTX_HSTR_EL2]
+
+ mrs x9, ICH_HCR_EL2
+ mrs x10, ICH_VMCR_EL2
+ stp x9, x10, [x0, #CTX_ICH_HCR_EL2]
+
+ mrs x11, mair_el2
+ mrs x12, mdcr_el2
+ stp x11, x12, [x0, #CTX_MAIR_EL2]
+
+ mrs x14, sctlr_el2
+ str x14, [x0, #CTX_SCTLR_EL2]
+
+ mrs x15, spsr_el2
+ mrs x16, sp_el2
+ stp x15, x16, [x0, #CTX_SPSR_EL2]
+
+ mrs x9, tcr_el2
+ mrs x10, tpidr_el2
+ stp x9, x10, [x0, #CTX_TCR_EL2]
+
+ mrs x11, ttbr0_el2
+ mrs x12, vbar_el2
+ stp x11, x12, [x0, #CTX_TTBR0_EL2]
+
+ mrs x13, vmpidr_el2
+ mrs x14, vpidr_el2
+ stp x13, x14, [x0, #CTX_VMPIDR_EL2]
+
+ mrs x15, vtcr_el2
+ mrs x16, vttbr_el2
+ stp x15, x16, [x0, #CTX_VTCR_EL2]
+ ret
+endfunc el2_sysregs_context_save_common
+
+func el2_sysregs_context_restore_common
+ ldp x9, x10, [x0, #CTX_ACTLR_EL2]
+ msr actlr_el2, x9
+ msr afsr0_el2, x10
+
+ ldp x11, x12, [x0, #CTX_AFSR1_EL2]
+ msr afsr1_el2, x11
+ msr amair_el2, x12
+
+ ldp x13, x14, [x0, #CTX_CNTHCTL_EL2]
+ msr cnthctl_el2, x13
+ msr cntvoff_el2, x14
+
+ ldr x15, [x0, #CTX_CPTR_EL2]
+ msr cptr_el2, x15
+
+#if CTX_INCLUDE_AARCH32_REGS
+ ldr x16, [x0, #CTX_DBGVCR32_EL2]
+ msr dbgvcr32_el2, x16
+#endif /* CTX_INCLUDE_AARCH32_REGS */
+
+ ldp x9, x10, [x0, #CTX_ELR_EL2]
+ msr elr_el2, x9
+ msr esr_el2, x10
+
+ ldp x11, x12, [x0, #CTX_FAR_EL2]
+ msr far_el2, x11
+ msr hacr_el2, x12
+
+ ldp x13, x14, [x0, #CTX_HCR_EL2]
+ msr hcr_el2, x13
+ msr hpfar_el2, x14
+
+ ldp x15, x16, [x0, #CTX_HSTR_EL2]
+ msr hstr_el2, x15
+ msr ICC_SRE_EL2, x16
+
+ ldp x9, x10, [x0, #CTX_ICH_HCR_EL2]
+ msr ICH_HCR_EL2, x9
+ msr ICH_VMCR_EL2, x10
+
+ ldp x11, x12, [x0, #CTX_MAIR_EL2]
+ msr mair_el2, x11
+ msr mdcr_el2, x12
+
+ ldr x14, [x0, #CTX_SCTLR_EL2]
+ msr sctlr_el2, x14
+
+ ldp x15, x16, [x0, #CTX_SPSR_EL2]
+ msr spsr_el2, x15
+ msr sp_el2, x16
+
+ ldp x9, x10, [x0, #CTX_TCR_EL2]
+ msr tcr_el2, x9
+ msr tpidr_el2, x10
+
+ ldp x11, x12, [x0, #CTX_TTBR0_EL2]
+ msr ttbr0_el2, x11
+ msr vbar_el2, x12
+
+ ldp x13, x14, [x0, #CTX_VMPIDR_EL2]
+ msr vmpidr_el2, x13
+ msr vpidr_el2, x14
+
+ ldp x15, x16, [x0, #CTX_VTCR_EL2]
+ msr vtcr_el2, x15
+ msr vttbr_el2, x16
+ ret
+endfunc el2_sysregs_context_restore_common
+
+#if ENABLE_SPE_FOR_LOWER_ELS
+func el2_sysregs_context_save_spe
+ mrs x13, PMSCR_EL2
+ str x13, [x0, #CTX_PMSCR_EL2]
+ ret
+endfunc el2_sysregs_context_save_spe
+
+func el2_sysregs_context_restore_spe
+ ldr x13, [x0, #CTX_PMSCR_EL2]
+ msr PMSCR_EL2, x13
+ ret
+endfunc el2_sysregs_context_restore_spe
+#endif /* ENABLE_SPE_FOR_LOWER_ELS */
+
+#if CTX_INCLUDE_MTE_REGS
+func el2_sysregs_context_save_mte
+ mrs x9, TFSR_EL2
+ str x9, [x0, #CTX_TFSR_EL2]
+ ret
+endfunc el2_sysregs_context_save_mte
+
+func el2_sysregs_context_restore_mte
+ ldr x9, [x0, #CTX_TFSR_EL2]
+ msr TFSR_EL2, x9
+ ret
+endfunc el2_sysregs_context_restore_mte
+#endif /* CTX_INCLUDE_MTE_REGS */
+
+#if ENABLE_MPAM_FOR_LOWER_ELS
+func el2_sysregs_context_save_mpam
+ mrs x10, MPAM2_EL2
+ str x10, [x0, #CTX_MPAM2_EL2]
+
+ mrs x11, MPAMHCR_EL2
+ mrs x12, MPAMVPM0_EL2
+ stp x11, x12, [x0, #CTX_MPAMHCR_EL2]
+
+ mrs x13, MPAMVPM1_EL2
+ mrs x14, MPAMVPM2_EL2
+ stp x13, x14, [x0, #CTX_MPAMVPM1_EL2]
+
+ mrs x15, MPAMVPM3_EL2
+ mrs x16, MPAMVPM4_EL2
+ stp x15, x16, [x0, #CTX_MPAMVPM3_EL2]
+
+ mrs x9, MPAMVPM5_EL2
+ mrs x10, MPAMVPM6_EL2
+ stp x9, x10, [x0, #CTX_MPAMVPM5_EL2]
+
+ mrs x11, MPAMVPM7_EL2
+ mrs x12, MPAMVPMV_EL2
+ stp x11, x12, [x0, #CTX_MPAMVPM7_EL2]
+ ret
+endfunc func el2_sysregs_context_save_mpam
+
+func el2_sysregs_context_restore_mpam
+ ldr x10, [x0, #CTX_MPAM2_EL2]
+ msr MPAM2_EL2, x10
+
+ ldp x11, x12, [x0, #CTX_MPAMHCR_EL2]
+ msr MPAMHCR_EL2, x11
+ msr MPAMVPM0_EL2, x12
+
+ ldp x13, x14, [x0, #CTX_MPAMVPM1_EL2]
+ msr MPAMVPM1_EL2, x13
+ msr MPAMVPM2_EL2, x14
+
+ ldp x15, x16, [x0, #CTX_MPAMVPM3_EL2]
+ msr MPAMVPM3_EL2, x15
+ msr MPAMVPM4_EL2, x16
+
+ ldp x9, x10, [x0, #CTX_MPAMVPM5_EL2]
+ msr MPAMVPM5_EL2, x9
+ msr MPAMVPM6_EL2, x10
+
+ ldp x11, x12, [x0, #CTX_MPAMVPM7_EL2]
+ msr MPAMVPM7_EL2, x11
+ msr MPAMVPMV_EL2, x12
+ ret
+endfunc el2_sysregs_context_restore_mpam
+#endif /* ENABLE_MPAM_FOR_LOWER_ELS */
+
+#if ENABLE_FEAT_FGT
+func el2_sysregs_context_save_fgt
+ mrs x13, HDFGRTR_EL2
+#if ENABLE_FEAT_AMUv1
+ mrs x14, HAFGRTR_EL2
+ stp x13, x14, [x0, #CTX_HDFGRTR_EL2]
+#else
+ str x13, [x0, #CTX_HDFGRTR_EL2]
+#endif /* ENABLE_FEAT_AMUv1 */
+ mrs x15, HDFGWTR_EL2
+ mrs x16, HFGITR_EL2
+ stp x15, x16, [x0, #CTX_HDFGWTR_EL2]
+
+ mrs x9, HFGRTR_EL2
+ mrs x10, HFGWTR_EL2
+ stp x9, x10, [x0, #CTX_HFGRTR_EL2]
+ ret
+endfunc el2_sysregs_context_save_fgt
+
+func el2_sysregs_context_restore_fgt
+ #if ENABLE_FEAT_AMUv1
+ ldp x13, x14, [x0, #CTX_HDFGRTR_EL2]
+ msr HAFGRTR_EL2, x14
+#else
+ ldr x13, [x0, #CTX_HDFGRTR_EL2]
+#endif /* ENABLE_FEAT_AMUv1 */
+ msr HDFGRTR_EL2, x13
+
+ ldp x15, x16, [x0, #CTX_HDFGWTR_EL2]
+ msr HDFGWTR_EL2, x15
+ msr HFGITR_EL2, x16
+
+ ldp x9, x10, [x0, #CTX_HFGRTR_EL2]
+ msr HFGRTR_EL2, x9
+ msr HFGWTR_EL2, x10
+ ret
+endfunc el2_sysregs_context_restore_fgt
+#endif /* ENABLE_FEAT_FGT */
+
+#if ENABLE_FEAT_ECV
+func el2_sysregs_context_save_ecv
+ mrs x11, CNTPOFF_EL2
+ str x11, [x0, #CTX_CNTPOFF_EL2]
+ ret
+endfunc el2_sysregs_context_save_ecv
+
+func el2_sysregs_context_restore_ecv
+ ldr x11, [x0, #CTX_CNTPOFF_EL2]
+ msr CNTPOFF_EL2, x11
+ ret
+endfunc el2_sysregs_context_restore_ecv
+#endif /* ENABLE_FEAT_ECV */
+
+#if ENABLE_FEAT_VHE
+func el2_sysregs_context_save_vhe
+ /*
+ * CONTEXTIDR_EL2 register is saved only when FEAT_VHE or
+ * FEAT_Debugv8p2 (currently not in TF-A) is supported.
+ */
+ mrs x9, contextidr_el2
+ mrs x10, ttbr1_el2
+ stp x9, x10, [x0, #CTX_CONTEXTIDR_EL2]
+ ret
+endfunc el2_sysregs_context_save_vhe
+
+func el2_sysregs_context_restore_vhe
+ /*
+ * CONTEXTIDR_EL2 register is restored only when FEAT_VHE or
+ * FEAT_Debugv8p2 (currently not in TF-A) is supported.
+ */
+ ldp x9, x10, [x0, #CTX_CONTEXTIDR_EL2]
+ msr contextidr_el2, x9
+ msr ttbr1_el2, x10
+ ret
+endfunc el2_sysregs_context_restore_vhe
+#endif /* ENABLE_FEAT_VHE */
+
+#if RAS_EXTENSION
+func el2_sysregs_context_save_ras
+ /*
+ * VDISR_EL2 and VSESR_EL2 registers are saved only when
+ * FEAT_RAS is supported.
+ */
+ mrs x11, vdisr_el2
+ mrs x12, vsesr_el2
+ stp x11, x12, [x0, #CTX_VDISR_EL2]
+ ret
+endfunc el2_sysregs_context_save_ras
+
+func el2_sysregs_context_restore_ras
+ /*
+ * VDISR_EL2 and VSESR_EL2 registers are restored only when FEAT_RAS
+ * is supported.
+ */
+ ldp x11, x12, [x0, #CTX_VDISR_EL2]
+ msr vdisr_el2, x11
+ msr vsesr_el2, x12
+ ret
+endfunc el2_sysregs_context_restore_ras
+#endif /* RAS_EXTENSION */
+
+#if CTX_INCLUDE_NEVE_REGS
+func el2_sysregs_context_save_nv2
+ /*
+ * VNCR_EL2 register is saved only when FEAT_NV2 is supported.
+ */
+ mrs x16, vncr_el2
+ str x16, [x0, #CTX_VNCR_EL2]
+ ret
+endfunc el2_sysregs_context_save_nv2
+
+func el2_sysregs_context_restore_nv2
+ /*
+ * VNCR_EL2 register is restored only when FEAT_NV2 is supported.
+ */
+ ldr x16, [x0, #CTX_VNCR_EL2]
+ msr vncr_el2, x16
+ ret
+endfunc el2_sysregs_context_restore_nv2
+#endif /* CTX_INCLUDE_NEVE_REGS */
+
+#if ENABLE_TRF_FOR_NS
+func el2_sysregs_context_save_trf
+ /*
+ * TRFCR_EL2 register is saved only when FEAT_TRF is supported.
+ */
+ mrs x12, TRFCR_EL2
+ str x12, [x0, #CTX_TRFCR_EL2]
+ ret
+endfunc el2_sysregs_context_save_trf
+
+func el2_sysregs_context_restore_trf
+ /*
+ * TRFCR_EL2 register is restored only when FEAT_TRF is supported.
+ */
+ ldr x12, [x0, #CTX_TRFCR_EL2]
+ msr TRFCR_EL2, x12
+ ret
+endfunc el2_sysregs_context_restore_trf
+#endif /* ENABLE_TRF_FOR_NS */
+
+#if ENABLE_FEAT_CSV2_2
+func el2_sysregs_context_save_csv2
+ /*
+ * SCXTNUM_EL2 register is saved only when FEAT_CSV2_2 is supported.
+ */
+ mrs x13, scxtnum_el2
+ str x13, [x0, #CTX_SCXTNUM_EL2]
+ ret
+endfunc el2_sysregs_context_save_csv2
+
+func el2_sysregs_context_restore_csv2
+ /*
+ * SCXTNUM_EL2 register is restored only when FEAT_CSV2_2 is supported.
+ */
+ ldr x13, [x0, #CTX_SCXTNUM_EL2]
+ msr scxtnum_el2, x13
+ ret
+endfunc el2_sysregs_context_restore_csv2
+#endif /* ENABLE_FEAT_CSV2_2 */
+
+#if ENABLE_FEAT_HCX
+func el2_sysregs_context_save_hcx
+ mrs x14, hcrx_el2
+ str x14, [x0, #CTX_HCRX_EL2]
+ ret
+endfunc el2_sysregs_context_save_hcx
+
+func el2_sysregs_context_restore_hcx
+ ldr x14, [x0, #CTX_HCRX_EL2]
+ msr hcrx_el2, x14
+ ret
+endfunc el2_sysregs_context_restore_hcx
+#endif /* ENABLE_FEAT_HCX */
+#endif /* CTX_INCLUDE_EL2_REGS */
+
+/* ------------------------------------------------------------------
+ * The following function strictly follows the AArch64 PCS to use
+ * x9-x17 (temporary caller-saved registers) to save EL1 system
+ * register context. It assumes that 'x0' is pointing to a
+ * 'el1_sys_regs' structure where the register context will be saved.
+ * ------------------------------------------------------------------
+ */
+func el1_sysregs_context_save
+
+ mrs x9, spsr_el1
+ mrs x10, elr_el1
+ stp x9, x10, [x0, #CTX_SPSR_EL1]
+
+#if !ERRATA_SPECULATIVE_AT
+ mrs x15, sctlr_el1
+ mrs x16, tcr_el1
+ stp x15, x16, [x0, #CTX_SCTLR_EL1]
+#endif /* ERRATA_SPECULATIVE_AT */
+
+ mrs x17, cpacr_el1
+ mrs x9, csselr_el1
+ stp x17, x9, [x0, #CTX_CPACR_EL1]
+
+ mrs x10, sp_el1
+ mrs x11, esr_el1
+ stp x10, x11, [x0, #CTX_SP_EL1]
+
+ mrs x12, ttbr0_el1
+ mrs x13, ttbr1_el1
+ stp x12, x13, [x0, #CTX_TTBR0_EL1]
+
+ mrs x14, mair_el1
+ mrs x15, amair_el1
+ stp x14, x15, [x0, #CTX_MAIR_EL1]
+
+ mrs x16, actlr_el1
+ mrs x17, tpidr_el1
+ stp x16, x17, [x0, #CTX_ACTLR_EL1]
+
+ mrs x9, tpidr_el0
+ mrs x10, tpidrro_el0
+ stp x9, x10, [x0, #CTX_TPIDR_EL0]
+
+ mrs x13, par_el1
+ mrs x14, far_el1
+ stp x13, x14, [x0, #CTX_PAR_EL1]
+
+ mrs x15, afsr0_el1
+ mrs x16, afsr1_el1
+ stp x15, x16, [x0, #CTX_AFSR0_EL1]
+
+ mrs x17, contextidr_el1
+ mrs x9, vbar_el1
+ stp x17, x9, [x0, #CTX_CONTEXTIDR_EL1]
+
+ /* Save AArch32 system registers if the build has instructed so */
+#if CTX_INCLUDE_AARCH32_REGS
+ mrs x11, spsr_abt
+ mrs x12, spsr_und
+ stp x11, x12, [x0, #CTX_SPSR_ABT]
+
+ mrs x13, spsr_irq
+ mrs x14, spsr_fiq
+ stp x13, x14, [x0, #CTX_SPSR_IRQ]
+
+ mrs x15, dacr32_el2
+ mrs x16, ifsr32_el2
+ stp x15, x16, [x0, #CTX_DACR32_EL2]
+#endif /* CTX_INCLUDE_AARCH32_REGS */
+
+ /* Save NS timer registers if the build has instructed so */
+#if NS_TIMER_SWITCH
+ mrs x10, cntp_ctl_el0
+ mrs x11, cntp_cval_el0
+ stp x10, x11, [x0, #CTX_CNTP_CTL_EL0]
+
+ mrs x12, cntv_ctl_el0
+ mrs x13, cntv_cval_el0
+ stp x12, x13, [x0, #CTX_CNTV_CTL_EL0]
+
+ mrs x14, cntkctl_el1
+ str x14, [x0, #CTX_CNTKCTL_EL1]
+#endif /* NS_TIMER_SWITCH */
+
+ /* Save MTE system registers if the build has instructed so */
+#if CTX_INCLUDE_MTE_REGS
+ mrs x15, TFSRE0_EL1
+ mrs x16, TFSR_EL1
+ stp x15, x16, [x0, #CTX_TFSRE0_EL1]
+
+ mrs x9, RGSR_EL1
+ mrs x10, GCR_EL1
+ stp x9, x10, [x0, #CTX_RGSR_EL1]
+#endif /* CTX_INCLUDE_MTE_REGS */
+
+ ret
+endfunc el1_sysregs_context_save
+
+/* ------------------------------------------------------------------
+ * The following function strictly follows the AArch64 PCS to use
+ * x9-x17 (temporary caller-saved registers) to restore EL1 system
+ * register context. It assumes that 'x0' is pointing to a
+ * 'el1_sys_regs' structure from where the register context will be
+ * restored
+ * ------------------------------------------------------------------
+ */
+func el1_sysregs_context_restore
+
+ ldp x9, x10, [x0, #CTX_SPSR_EL1]
+ msr spsr_el1, x9
+ msr elr_el1, x10
+
+#if !ERRATA_SPECULATIVE_AT
+ ldp x15, x16, [x0, #CTX_SCTLR_EL1]
+ msr sctlr_el1, x15
+ msr tcr_el1, x16
+#endif /* ERRATA_SPECULATIVE_AT */
+
+ ldp x17, x9, [x0, #CTX_CPACR_EL1]
+ msr cpacr_el1, x17
+ msr csselr_el1, x9
+
+ ldp x10, x11, [x0, #CTX_SP_EL1]
+ msr sp_el1, x10
+ msr esr_el1, x11
+
+ ldp x12, x13, [x0, #CTX_TTBR0_EL1]
+ msr ttbr0_el1, x12
+ msr ttbr1_el1, x13
+
+ ldp x14, x15, [x0, #CTX_MAIR_EL1]
+ msr mair_el1, x14
+ msr amair_el1, x15
+
+ ldp x16, x17, [x0, #CTX_ACTLR_EL1]
+ msr actlr_el1, x16
+ msr tpidr_el1, x17
+
+ ldp x9, x10, [x0, #CTX_TPIDR_EL0]
+ msr tpidr_el0, x9
+ msr tpidrro_el0, x10
+
+ ldp x13, x14, [x0, #CTX_PAR_EL1]
+ msr par_el1, x13
+ msr far_el1, x14
+
+ ldp x15, x16, [x0, #CTX_AFSR0_EL1]
+ msr afsr0_el1, x15
+ msr afsr1_el1, x16
+
+ ldp x17, x9, [x0, #CTX_CONTEXTIDR_EL1]
+ msr contextidr_el1, x17
+ msr vbar_el1, x9
+
+ /* Restore AArch32 system registers if the build has instructed so */
+#if CTX_INCLUDE_AARCH32_REGS
+ ldp x11, x12, [x0, #CTX_SPSR_ABT]
+ msr spsr_abt, x11
+ msr spsr_und, x12
+
+ ldp x13, x14, [x0, #CTX_SPSR_IRQ]
+ msr spsr_irq, x13
+ msr spsr_fiq, x14
+
+ ldp x15, x16, [x0, #CTX_DACR32_EL2]
+ msr dacr32_el2, x15
+ msr ifsr32_el2, x16
+#endif /* CTX_INCLUDE_AARCH32_REGS */
+
+ /* Restore NS timer registers if the build has instructed so */
+#if NS_TIMER_SWITCH
+ ldp x10, x11, [x0, #CTX_CNTP_CTL_EL0]
+ msr cntp_ctl_el0, x10
+ msr cntp_cval_el0, x11
+
+ ldp x12, x13, [x0, #CTX_CNTV_CTL_EL0]
+ msr cntv_ctl_el0, x12
+ msr cntv_cval_el0, x13
+
+ ldr x14, [x0, #CTX_CNTKCTL_EL1]
+ msr cntkctl_el1, x14
+#endif /* NS_TIMER_SWITCH */
+
+ /* Restore MTE system registers if the build has instructed so */
+#if CTX_INCLUDE_MTE_REGS
+ ldp x11, x12, [x0, #CTX_TFSRE0_EL1]
+ msr TFSRE0_EL1, x11
+ msr TFSR_EL1, x12
+
+ ldp x13, x14, [x0, #CTX_RGSR_EL1]
+ msr RGSR_EL1, x13
+ msr GCR_EL1, x14
+#endif /* CTX_INCLUDE_MTE_REGS */
+
+ /* No explict ISB required here as ERET covers it */
+ ret
+endfunc el1_sysregs_context_restore
+
+/* ------------------------------------------------------------------
+ * The following function follows the aapcs_64 strictly to use
+ * x9-x17 (temporary caller-saved registers according to AArch64 PCS)
+ * to save floating point register context. It assumes that 'x0' is
+ * pointing to a 'fp_regs' structure where the register context will
+ * be saved.
+ *
+ * Access to VFP registers will trap if CPTR_EL3.TFP is set.
+ * However currently we don't use VFP registers nor set traps in
+ * Trusted Firmware, and assume it's cleared.
+ *
+ * TODO: Revisit when VFP is used in secure world
+ * ------------------------------------------------------------------
+ */
+#if CTX_INCLUDE_FPREGS
+func fpregs_context_save
+ stp q0, q1, [x0, #CTX_FP_Q0]
+ stp q2, q3, [x0, #CTX_FP_Q2]
+ stp q4, q5, [x0, #CTX_FP_Q4]
+ stp q6, q7, [x0, #CTX_FP_Q6]
+ stp q8, q9, [x0, #CTX_FP_Q8]
+ stp q10, q11, [x0, #CTX_FP_Q10]
+ stp q12, q13, [x0, #CTX_FP_Q12]
+ stp q14, q15, [x0, #CTX_FP_Q14]
+ stp q16, q17, [x0, #CTX_FP_Q16]
+ stp q18, q19, [x0, #CTX_FP_Q18]
+ stp q20, q21, [x0, #CTX_FP_Q20]
+ stp q22, q23, [x0, #CTX_FP_Q22]
+ stp q24, q25, [x0, #CTX_FP_Q24]
+ stp q26, q27, [x0, #CTX_FP_Q26]
+ stp q28, q29, [x0, #CTX_FP_Q28]
+ stp q30, q31, [x0, #CTX_FP_Q30]
+
+ mrs x9, fpsr
+ str x9, [x0, #CTX_FP_FPSR]
+
+ mrs x10, fpcr
+ str x10, [x0, #CTX_FP_FPCR]
+
+#if CTX_INCLUDE_AARCH32_REGS
+ mrs x11, fpexc32_el2
+ str x11, [x0, #CTX_FP_FPEXC32_EL2]
+#endif /* CTX_INCLUDE_AARCH32_REGS */
+ ret
+endfunc fpregs_context_save
+
+/* ------------------------------------------------------------------
+ * The following function follows the aapcs_64 strictly to use x9-x17
+ * (temporary caller-saved registers according to AArch64 PCS) to
+ * restore floating point register context. It assumes that 'x0' is
+ * pointing to a 'fp_regs' structure from where the register context
+ * will be restored.
+ *
+ * Access to VFP registers will trap if CPTR_EL3.TFP is set.
+ * However currently we don't use VFP registers nor set traps in
+ * Trusted Firmware, and assume it's cleared.
+ *
+ * TODO: Revisit when VFP is used in secure world
+ * ------------------------------------------------------------------
+ */
+func fpregs_context_restore
+ ldp q0, q1, [x0, #CTX_FP_Q0]
+ ldp q2, q3, [x0, #CTX_FP_Q2]
+ ldp q4, q5, [x0, #CTX_FP_Q4]
+ ldp q6, q7, [x0, #CTX_FP_Q6]
+ ldp q8, q9, [x0, #CTX_FP_Q8]
+ ldp q10, q11, [x0, #CTX_FP_Q10]
+ ldp q12, q13, [x0, #CTX_FP_Q12]
+ ldp q14, q15, [x0, #CTX_FP_Q14]
+ ldp q16, q17, [x0, #CTX_FP_Q16]
+ ldp q18, q19, [x0, #CTX_FP_Q18]
+ ldp q20, q21, [x0, #CTX_FP_Q20]
+ ldp q22, q23, [x0, #CTX_FP_Q22]
+ ldp q24, q25, [x0, #CTX_FP_Q24]
+ ldp q26, q27, [x0, #CTX_FP_Q26]
+ ldp q28, q29, [x0, #CTX_FP_Q28]
+ ldp q30, q31, [x0, #CTX_FP_Q30]
+
+ ldr x9, [x0, #CTX_FP_FPSR]
+ msr fpsr, x9
+
+ ldr x10, [x0, #CTX_FP_FPCR]
+ msr fpcr, x10
+
+#if CTX_INCLUDE_AARCH32_REGS
+ ldr x11, [x0, #CTX_FP_FPEXC32_EL2]
+ msr fpexc32_el2, x11
+#endif /* CTX_INCLUDE_AARCH32_REGS */
+
+ /*
+ * No explict ISB required here as ERET to
+ * switch to secure EL1 or non-secure world
+ * covers it
+ */
+
+ ret
+endfunc fpregs_context_restore
+#endif /* CTX_INCLUDE_FPREGS */
+
+ /*
+ * Set the PSTATE bits not set when the exception was taken as
+ * described in the AArch64.TakeException() pseudocode function
+ * in ARM DDI 0487F.c page J1-7635 to a default value.
+ */
+ .macro set_unset_pstate_bits
+ /*
+ * If Data Independent Timing (DIT) functionality is implemented,
+ * always enable DIT in EL3
+ */
+#if ENABLE_FEAT_DIT
+ mov x8, #DIT_BIT
+ msr DIT, x8
+#endif /* ENABLE_FEAT_DIT */
+ .endm /* set_unset_pstate_bits */
+
+/* ------------------------------------------------------------------
+ * The following macro is used to save and restore all the general
+ * purpose and ARMv8.3-PAuth (if enabled) registers.
+ * It also checks if the Secure Cycle Counter (PMCCNTR_EL0)
+ * is disabled in EL3/Secure (ARMv8.5-PMU), wherein PMCCNTR_EL0
+ * needs not to be saved/restored during world switch.
+ *
+ * Ideally we would only save and restore the callee saved registers
+ * when a world switch occurs but that type of implementation is more
+ * complex. So currently we will always save and restore these
+ * registers on entry and exit of EL3.
+ * clobbers: x18
+ * ------------------------------------------------------------------
+ */
+ .macro save_gp_pmcr_pauth_regs
+ stp x0, x1, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X0]
+ stp x2, x3, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X2]
+ stp x4, x5, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X4]
+ stp x6, x7, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X6]
+ stp x8, x9, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X8]
+ stp x10, x11, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X10]
+ stp x12, x13, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X12]
+ stp x14, x15, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X14]
+ stp x16, x17, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X16]
+ stp x18, x19, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X18]
+ stp x20, x21, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X20]
+ stp x22, x23, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X22]
+ stp x24, x25, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X24]
+ stp x26, x27, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X26]
+ stp x28, x29, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X28]
+ mrs x18, sp_el0
+ str x18, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_SP_EL0]
+
+ /* ----------------------------------------------------------
+ * Check if earlier initialization of MDCR_EL3.SCCD/MCCD to 1
+ * has failed.
+ *
+ * MDCR_EL3:
+ * MCCD bit set, Prohibits the Cycle Counter PMCCNTR_EL0 from
+ * counting at EL3.
+ * SCCD bit set, Secure Cycle Counter Disable. Prohibits PMCCNTR_EL0
+ * from counting in Secure state.
+ * If these bits are not set, meaning that FEAT_PMUv3p5/7 is
+ * not implemented and PMCR_EL0 should be saved in non-secure
+ * context.
+ * ----------------------------------------------------------
+ */
+ mov_imm x10, (MDCR_SCCD_BIT | MDCR_MCCD_BIT)
+ mrs x9, mdcr_el3
+ tst x9, x10
+ bne 1f
+
+ /* ----------------------------------------------------------
+ * If control reaches here, it ensures the Secure Cycle
+ * Counter (PMCCNTR_EL0) is not prohibited from counting at
+ * EL3 and in secure states.
+ * Henceforth, PMCR_EL0 to be saved before world switch.
+ * ----------------------------------------------------------
+ */
+ mrs x9, pmcr_el0
+
+ /* Check caller's security state */
+ mrs x10, scr_el3
+ tst x10, #SCR_NS_BIT
+ beq 2f
+
+ /* Save PMCR_EL0 if called from Non-secure state */
+ str x9, [sp, #CTX_EL3STATE_OFFSET + CTX_PMCR_EL0]
+
+ /* Disable cycle counter when event counting is prohibited */
+2: orr x9, x9, #PMCR_EL0_DP_BIT
+ msr pmcr_el0, x9
+ isb
+1:
+#if CTX_INCLUDE_PAUTH_REGS
+ /* ----------------------------------------------------------
+ * Save the ARMv8.3-PAuth keys as they are not banked
+ * by exception level
+ * ----------------------------------------------------------
+ */
+ add x19, sp, #CTX_PAUTH_REGS_OFFSET
+
+ mrs x20, APIAKeyLo_EL1 /* x21:x20 = APIAKey */
+ mrs x21, APIAKeyHi_EL1
+ mrs x22, APIBKeyLo_EL1 /* x23:x22 = APIBKey */
+ mrs x23, APIBKeyHi_EL1
+ mrs x24, APDAKeyLo_EL1 /* x25:x24 = APDAKey */
+ mrs x25, APDAKeyHi_EL1
+ mrs x26, APDBKeyLo_EL1 /* x27:x26 = APDBKey */
+ mrs x27, APDBKeyHi_EL1
+ mrs x28, APGAKeyLo_EL1 /* x29:x28 = APGAKey */
+ mrs x29, APGAKeyHi_EL1
+
+ stp x20, x21, [x19, #CTX_PACIAKEY_LO]
+ stp x22, x23, [x19, #CTX_PACIBKEY_LO]
+ stp x24, x25, [x19, #CTX_PACDAKEY_LO]
+ stp x26, x27, [x19, #CTX_PACDBKEY_LO]
+ stp x28, x29, [x19, #CTX_PACGAKEY_LO]
+#endif /* CTX_INCLUDE_PAUTH_REGS */
+ .endm /* save_gp_pmcr_pauth_regs */
+
+/* -----------------------------------------------------------------
+ * This function saves the context and sets the PSTATE to a known
+ * state, preparing entry to el3.
+ * Save all the general purpose and ARMv8.3-PAuth (if enabled)
+ * registers.
+ * Then set any of the PSTATE bits that are not set by hardware
+ * according to the Aarch64.TakeException pseudocode in the Arm
+ * Architecture Reference Manual to a default value for EL3.
+ * clobbers: x17
+ * -----------------------------------------------------------------
+ */
+func prepare_el3_entry
+ save_gp_pmcr_pauth_regs
+ /*
+ * Set the PSTATE bits not described in the Aarch64.TakeException
+ * pseudocode to their default values.
+ */
+ set_unset_pstate_bits
+ ret
+endfunc prepare_el3_entry
+
+/* ------------------------------------------------------------------
+ * This function restores ARMv8.3-PAuth (if enabled) and all general
+ * purpose registers except x30 from the CPU context.
+ * x30 register must be explicitly restored by the caller.
+ * ------------------------------------------------------------------
+ */
+func restore_gp_pmcr_pauth_regs
+#if CTX_INCLUDE_PAUTH_REGS
+ /* Restore the ARMv8.3 PAuth keys */
+ add x10, sp, #CTX_PAUTH_REGS_OFFSET
+
+ ldp x0, x1, [x10, #CTX_PACIAKEY_LO] /* x1:x0 = APIAKey */
+ ldp x2, x3, [x10, #CTX_PACIBKEY_LO] /* x3:x2 = APIBKey */
+ ldp x4, x5, [x10, #CTX_PACDAKEY_LO] /* x5:x4 = APDAKey */
+ ldp x6, x7, [x10, #CTX_PACDBKEY_LO] /* x7:x6 = APDBKey */
+ ldp x8, x9, [x10, #CTX_PACGAKEY_LO] /* x9:x8 = APGAKey */
+
+ msr APIAKeyLo_EL1, x0
+ msr APIAKeyHi_EL1, x1
+ msr APIBKeyLo_EL1, x2
+ msr APIBKeyHi_EL1, x3
+ msr APDAKeyLo_EL1, x4
+ msr APDAKeyHi_EL1, x5
+ msr APDBKeyLo_EL1, x6
+ msr APDBKeyHi_EL1, x7
+ msr APGAKeyLo_EL1, x8
+ msr APGAKeyHi_EL1, x9
+#endif /* CTX_INCLUDE_PAUTH_REGS */
+
+ /* ----------------------------------------------------------
+ * Restore PMCR_EL0 when returning to Non-secure state if
+ * Secure Cycle Counter is not disabled in MDCR_EL3 when
+ * ARMv8.5-PMU is implemented.
+ * ----------------------------------------------------------
+ */
+ mrs x0, scr_el3
+ tst x0, #SCR_NS_BIT
+ beq 2f
+
+ /* ----------------------------------------------------------
+ * Back to Non-secure state.
+ * Check if earlier initialization MDCR_EL3.SCCD/MCCD to 1
+ * failed, meaning that FEAT_PMUv3p5/7 is not implemented and
+ * PMCR_EL0 should be restored from non-secure context.
+ * ----------------------------------------------------------
+ */
+ mov_imm x1, (MDCR_SCCD_BIT | MDCR_MCCD_BIT)
+ mrs x0, mdcr_el3
+ tst x0, x1
+ bne 2f
+ ldr x0, [sp, #CTX_EL3STATE_OFFSET + CTX_PMCR_EL0]
+ msr pmcr_el0, x0
+2:
+ ldp x0, x1, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X0]
+ ldp x2, x3, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X2]
+ ldp x4, x5, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X4]
+ ldp x6, x7, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X6]
+ ldp x8, x9, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X8]
+ ldp x10, x11, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X10]
+ ldp x12, x13, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X12]
+ ldp x14, x15, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X14]
+ ldp x16, x17, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X16]
+ ldp x18, x19, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X18]
+ ldp x20, x21, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X20]
+ ldp x22, x23, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X22]
+ ldp x24, x25, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X24]
+ ldp x26, x27, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X26]
+ ldr x28, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_SP_EL0]
+ msr sp_el0, x28
+ ldp x28, x29, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_X28]
+ ret
+endfunc restore_gp_pmcr_pauth_regs
+
+/*
+ * In case of ERRATA_SPECULATIVE_AT, save SCTLR_EL1 and TCR_EL1
+ * registers and update EL1 registers to disable stage1 and stage2
+ * page table walk
+ */
+func save_and_update_ptw_el1_sys_regs
+ /* ----------------------------------------------------------
+ * Save only sctlr_el1 and tcr_el1 registers
+ * ----------------------------------------------------------
+ */
+ mrs x29, sctlr_el1
+ str x29, [sp, #(CTX_EL1_SYSREGS_OFFSET + CTX_SCTLR_EL1)]
+ mrs x29, tcr_el1
+ str x29, [sp, #(CTX_EL1_SYSREGS_OFFSET + CTX_TCR_EL1)]
+
+ /* ------------------------------------------------------------
+ * Must follow below order in order to disable page table
+ * walk for lower ELs (EL1 and EL0). First step ensures that
+ * page table walk is disabled for stage1 and second step
+ * ensures that page table walker should use TCR_EL1.EPDx
+ * bits to perform address translation. ISB ensures that CPU
+ * does these 2 steps in order.
+ *
+ * 1. Update TCR_EL1.EPDx bits to disable page table walk by
+ * stage1.
+ * 2. Enable MMU bit to avoid identity mapping via stage2
+ * and force TCR_EL1.EPDx to be used by the page table
+ * walker.
+ * ------------------------------------------------------------
+ */
+ orr x29, x29, #(TCR_EPD0_BIT)
+ orr x29, x29, #(TCR_EPD1_BIT)
+ msr tcr_el1, x29
+ isb
+ mrs x29, sctlr_el1
+ orr x29, x29, #SCTLR_M_BIT
+ msr sctlr_el1, x29
+ isb
+
+ ret
+endfunc save_and_update_ptw_el1_sys_regs
+
+/* ------------------------------------------------------------------
+ * This routine assumes that the SP_EL3 is pointing to a valid
+ * context structure from where the gp regs and other special
+ * registers can be retrieved.
+ * ------------------------------------------------------------------
+ */
+func el3_exit
+#if ENABLE_ASSERTIONS
+ /* el3_exit assumes SP_EL0 on entry */
+ mrs x17, spsel
+ cmp x17, #MODE_SP_EL0
+ ASM_ASSERT(eq)
+#endif /* ENABLE_ASSERTIONS */
+
+ /* ----------------------------------------------------------
+ * Save the current SP_EL0 i.e. the EL3 runtime stack which
+ * will be used for handling the next SMC.
+ * Then switch to SP_EL3.
+ * ----------------------------------------------------------
+ */
+ mov x17, sp
+ msr spsel, #MODE_SP_ELX
+ str x17, [sp, #CTX_EL3STATE_OFFSET + CTX_RUNTIME_SP]
+
+ /* ----------------------------------------------------------
+ * Restore SPSR_EL3, ELR_EL3 and SCR_EL3 prior to ERET
+ * ----------------------------------------------------------
+ */
+ ldr x18, [sp, #CTX_EL3STATE_OFFSET + CTX_SCR_EL3]
+ ldp x16, x17, [sp, #CTX_EL3STATE_OFFSET + CTX_SPSR_EL3]
+ msr scr_el3, x18
+ msr spsr_el3, x16
+ msr elr_el3, x17
+
+#if IMAGE_BL31
+ /* ----------------------------------------------------------
+ * Restore CPTR_EL3.
+ * ZCR is only restored if SVE is supported and enabled.
+ * Synchronization is required before zcr_el3 is addressed.
+ * ----------------------------------------------------------
+ */
+ ldp x19, x20, [sp, #CTX_EL3STATE_OFFSET + CTX_CPTR_EL3]
+ msr cptr_el3, x19
+
+ ands x19, x19, #CPTR_EZ_BIT
+ beq sve_not_enabled
+
+ isb
+ msr S3_6_C1_C2_0, x20 /* zcr_el3 */
+sve_not_enabled:
+#endif /* IMAGE_BL31 */
+
+#if IMAGE_BL31 && DYNAMIC_WORKAROUND_CVE_2018_3639
+ /* ----------------------------------------------------------
+ * Restore mitigation state as it was on entry to EL3
+ * ----------------------------------------------------------
+ */
+ ldr x17, [sp, #CTX_CVE_2018_3639_OFFSET + CTX_CVE_2018_3639_DISABLE]
+ cbz x17, 1f
+ blr x17
+1:
+#endif /* IMAGE_BL31 && DYNAMIC_WORKAROUND_CVE_2018_3639 */
+
+ restore_ptw_el1_sys_regs
+
+ /* ----------------------------------------------------------
+ * Restore general purpose (including x30), PMCR_EL0 and
+ * ARMv8.3-PAuth registers.
+ * Exit EL3 via ERET to a lower exception level.
+ * ----------------------------------------------------------
+ */
+ bl restore_gp_pmcr_pauth_regs
+ ldr x30, [sp, #CTX_GPREGS_OFFSET + CTX_GPREG_LR]
+
+#if IMAGE_BL31 && RAS_EXTENSION
+ /* ----------------------------------------------------------
+ * Issue Error Synchronization Barrier to synchronize SErrors
+ * before exiting EL3. We're running with EAs unmasked, so
+ * any synchronized errors would be taken immediately;
+ * therefore no need to inspect DISR_EL1 register.
+ * ----------------------------------------------------------
+ */
+ esb
+#else
+ dsb sy
+#endif /* IMAGE_BL31 && RAS_EXTENSION */
+
+#ifdef IMAGE_BL31
+ str xzr, [sp, #CTX_EL3STATE_OFFSET + CTX_IS_IN_EL3]
+#endif /* IMAGE_BL31 */
+
+ exception_return
+
+endfunc el3_exit