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Diffstat (limited to 'OvmfPkg/ResetVector/Ia16/ResetVectorVtf0.asm')
-rw-r--r--OvmfPkg/ResetVector/Ia16/ResetVectorVtf0.asm100
1 files changed, 100 insertions, 0 deletions
diff --git a/OvmfPkg/ResetVector/Ia16/ResetVectorVtf0.asm b/OvmfPkg/ResetVector/Ia16/ResetVectorVtf0.asm
new file mode 100644
index 0000000000..980e0138e7
--- /dev/null
+++ b/OvmfPkg/ResetVector/Ia16/ResetVectorVtf0.asm
@@ -0,0 +1,100 @@
+;------------------------------------------------------------------------------
+; @file
+; First code executed by processor after resetting.
+; Derived from UefiCpuPkg/ResetVector/Vtf0/Ia16/ResetVectorVtf0.asm
+;
+; Copyright (c) 2008 - 2014, Intel Corporation. All rights reserved.<BR>
+; SPDX-License-Identifier: BSD-2-Clause-Patent
+;
+;------------------------------------------------------------------------------
+
+BITS 16
+
+ALIGN 16
+
+;
+; Pad the image size to 4k when page tables are in VTF0
+;
+; If the VTF0 image has page tables built in, then we need to make
+; sure the end of VTF0 is 4k above where the page tables end.
+;
+; This is required so the page tables will be 4k aligned when VTF0 is
+; located just below 0x100000000 (4GB) in the firmware device.
+;
+%ifdef ALIGN_TOP_TO_4K_FOR_PAGING
+ TIMES (0x1000 - ($ - EndOfPageTables) - 0x20) DB 0
+%endif
+
+;
+; SEV-ES Processor Reset support
+;
+; sevEsResetBlock:
+; For the initial boot of an AP under SEV-ES, the "reset" RIP must be
+; programmed to the RAM area defined by SEV_ES_AP_RESET_IP. A known offset
+; and GUID will be used to locate this block in the firmware and extract
+; the build time RIP value. The GUID must always be 48 bytes from the
+; end of the firmware.
+;
+; 0xffffffca (-0x36) - IP value
+; 0xffffffcc (-0x34) - CS segment base [31:16]
+; 0xffffffce (-0x32) - Size of the SEV-ES reset block
+; 0xffffffd0 (-0x30) - SEV-ES reset block GUID
+; (00f771de-1a7e-4fcb-890e-68c77e2fb44e)
+;
+; A hypervisor reads the CS segement base and IP value. The CS segment base
+; value represents the high order 16-bits of the CS segment base, so the
+; hypervisor must left shift the value of the CS segement base by 16 bits to
+; form the full CS segment base for the CS segment register. It would then
+; program the EIP register with the IP value as read.
+;
+
+TIMES (32 - (sevEsResetBlockEnd - sevEsResetBlockStart)) DB 0
+
+sevEsResetBlockStart:
+ DD SEV_ES_AP_RESET_IP
+ DW sevEsResetBlockEnd - sevEsResetBlockStart
+ DB 0xDE, 0x71, 0xF7, 0x00, 0x7E, 0x1A, 0xCB, 0x4F
+ DB 0x89, 0x0E, 0x68, 0xC7, 0x7E, 0x2F, 0xB4, 0x4E
+sevEsResetBlockEnd:
+
+ALIGN 16
+
+applicationProcessorEntryPoint:
+;
+; Application Processors entry point
+;
+; GenFv generates code aligned on a 4k boundary which will jump to this
+; location. (0xffffffe0) This allows the Local APIC Startup IPI to be
+; used to wake up the application processors.
+;
+ jmp EarlyApInitReal16
+
+ALIGN 8
+
+ DD 0
+
+;
+; The VTF signature
+;
+; VTF-0 means that the VTF (Volume Top File) code does not require
+; any fixups.
+;
+vtfSignature:
+ DB 'V', 'T', 'F', 0
+
+ALIGN 16
+
+resetVector:
+;
+; Reset Vector
+;
+; This is where the processor will begin execution
+;
+ nop
+ nop
+ jmp EarlyBspInitReal16
+
+ALIGN 16
+
+fourGigabytes:
+