5a7cbd54a1
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3275 The PVALIDATE instruction validates or rescinds validation of a guest page RMP entry. Upon completion, a return code is stored in EAX, rFLAGS bits OF, ZF, AF, PF and SF are set based on this return code. If the instruction completed succesfully, the rFLAGS bit CF indicates if the contents of the RMP entry were changed or not. For more information about the instruction see AMD APM volume 3. Cc: James Bottomley <jejb@linux.ibm.com> Cc: Min Xu <min.m.xu@intel.com> Cc: Jiewen Yao <jiewen.yao@intel.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Jordan Justen <jordan.l.justen@intel.com> Cc: Ard Biesheuvel <ardb+tianocore@kernel.org> Cc: Laszlo Ersek <lersek@redhat.com> Cc: Erdem Aktas <erdemaktas@google.com> Cc: Michael D Kinney <michael.d.kinney@intel.com> Cc: Liming Gao <gaoliming@byosoft.com.cn> Cc: Zhiguang Liu <zhiguang.liu@intel.com> Reviewed-by: Liming Gao <gaoliming@byosoft.com.cn> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Message-Id: <20210519181949.6574-8-brijesh.singh@amd.com>
43 lines
1.1 KiB
NASM
43 lines
1.1 KiB
NASM
;-----------------------------------------------------------------------------
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;
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; Copyright (c) 2021, AMD. All rights reserved.<BR>
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; SPDX-License-Identifier: BSD-2-Clause-Patent
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;
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;-----------------------------------------------------------------------------
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%include "Nasm.inc"
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SECTION .text
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;-----------------------------------------------------------------------------
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; UINT32
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; EFIAPI
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; AsmPvalidate (
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; IN UINT32 PageSize
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; IN UINT32 Validate,
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; IN UINT64 Address
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; )
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;-----------------------------------------------------------------------------
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global ASM_PFX(AsmPvalidate)
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ASM_PFX(AsmPvalidate):
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mov rax, r8
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PVALIDATE
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; Save the carry flag.
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setc dl
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; The PVALIDATE instruction returns the status in rax register.
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cmp rax, 0
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jne PvalidateExit
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; Check the carry flag to determine if RMP entry was updated.
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cmp dl, 0
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je PvalidateExit
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; Return the PVALIDATE_RET_NO_RMPUPDATE.
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mov rax, 255
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PvalidateExit:
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ret
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