OvmfPkg: Introduce XenResetVector

Introduce XenResetVector, a copy of OvmfPkg/ResetVector, with one
changes:
  - SEC_DEFAULT_CR0: enable cache (bit 30 or CD set to 0)

Xen copies the OVMF code to RAM, there is no need to disable cache.

This new module will later be modified to add a new entry point, more
detail in a following commit "OvmfPkg/XenResetVector: Add new entry point
for Xen PVH"

Value FILE_GUID of XenResetVector have not changed compare to ResetVector
because it is a special value (gEfiFirmwareVolumeTopFileGuid).

Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1689
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20190813113119.14804-4-anthony.perard@citrix.com>
This commit is contained in:
Anthony PERARD 2019-08-13 12:30:47 +01:00 committed by Laszlo Ersek
parent 75e85e3382
commit c05de360ec
7 changed files with 392 additions and 2 deletions

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@ -380,6 +380,7 @@ F: OvmfPkg/SmbiosPlatformDxe/*Xen.c
F: OvmfPkg/XenBusDxe/
F: OvmfPkg/XenIoPciDxe/
F: OvmfPkg/XenPvBlkDxe/
F: OvmfPkg/XenResetVector/
R: Anthony Perard <anthony.perard@citrix.com>
R: Julien Grall <julien.grall@arm.com>

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@ -495,7 +495,7 @@
#
################################################################################
[Components]
OvmfPkg/ResetVector/ResetVector.inf
OvmfPkg/XenResetVector/XenResetVector.inf
#
# SEC Phase modules

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@ -118,7 +118,7 @@ READ_LOCK_STATUS = TRUE
#
INF OvmfPkg/Sec/SecMain.inf
INF RuleOverride=RESET_VECTOR OvmfPkg/ResetVector/ResetVector.inf
INF RuleOverride=RESET_VECTOR OvmfPkg/XenResetVector/XenResetVector.inf
################################################################################
[FV.PEIFV]

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@ -0,0 +1,134 @@
;------------------------------------------------------------------------------
; @file
; Transition from 16 bit real mode into 32 bit flat protected mode
;
; Copyright (c) 2008 - 2010, Intel Corporation. All rights reserved.<BR>
; Copyright (c) 2019, Citrix Systems, Inc.
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
;------------------------------------------------------------------------------
%define SEC_DEFAULT_CR0 0x00000023
%define SEC_DEFAULT_CR4 0x640
BITS 16
;
; Modified: EAX, EBX
;
; @param[out] DS Selector allowing flat access to all addresses
; @param[out] ES Selector allowing flat access to all addresses
; @param[out] FS Selector allowing flat access to all addresses
; @param[out] GS Selector allowing flat access to all addresses
; @param[out] SS Selector allowing flat access to all addresses
;
TransitionFromReal16To32BitFlat:
debugShowPostCode POSTCODE_16BIT_MODE
cli
mov bx, 0xf000
mov ds, bx
mov bx, ADDR16_OF(gdtr)
o32 lgdt [cs:bx]
mov eax, SEC_DEFAULT_CR0
mov cr0, eax
jmp LINEAR_CODE_SEL:dword ADDR_OF(jumpTo32BitAndLandHere)
BITS 32
jumpTo32BitAndLandHere:
mov eax, SEC_DEFAULT_CR4
mov cr4, eax
debugShowPostCode POSTCODE_32BIT_MODE
mov ax, LINEAR_SEL
mov ds, ax
mov es, ax
mov fs, ax
mov gs, ax
mov ss, ax
OneTimeCallRet TransitionFromReal16To32BitFlat
ALIGN 2
gdtr:
dw GDT_END - GDT_BASE - 1 ; GDT limit
dd ADDR_OF(GDT_BASE)
ALIGN 16
;
; Macros for GDT entries
;
%define PRESENT_FLAG(p) (p << 7)
%define DPL(dpl) (dpl << 5)
%define SYSTEM_FLAG(s) (s << 4)
%define DESC_TYPE(t) (t)
; Type: data, expand-up, writable, accessed
%define DATA32_TYPE 3
; Type: execute, readable, expand-up, accessed
%define CODE32_TYPE 0xb
; Type: execute, readable, expand-up, accessed
%define CODE64_TYPE 0xb
%define GRANULARITY_FLAG(g) (g << 7)
%define DEFAULT_SIZE32(d) (d << 6)
%define CODE64_FLAG(l) (l << 5)
%define UPPER_LIMIT(l) (l)
;
; The Global Descriptor Table (GDT)
;
GDT_BASE:
; null descriptor
NULL_SEL equ $-GDT_BASE
DW 0 ; limit 15:0
DW 0 ; base 15:0
DB 0 ; base 23:16
DB 0 ; sys flag, dpl, type
DB 0 ; limit 19:16, flags
DB 0 ; base 31:24
; linear data segment descriptor
LINEAR_SEL equ $-GDT_BASE
DW 0xffff ; limit 15:0
DW 0 ; base 15:0
DB 0 ; base 23:16
DB PRESENT_FLAG(1)|DPL(0)|SYSTEM_FLAG(1)|DESC_TYPE(DATA32_TYPE)
DB GRANULARITY_FLAG(1)|DEFAULT_SIZE32(1)|CODE64_FLAG(0)|UPPER_LIMIT(0xf)
DB 0 ; base 31:24
; linear code segment descriptor
LINEAR_CODE_SEL equ $-GDT_BASE
DW 0xffff ; limit 15:0
DW 0 ; base 15:0
DB 0 ; base 23:16
DB PRESENT_FLAG(1)|DPL(0)|SYSTEM_FLAG(1)|DESC_TYPE(CODE32_TYPE)
DB GRANULARITY_FLAG(1)|DEFAULT_SIZE32(1)|CODE64_FLAG(0)|UPPER_LIMIT(0xf)
DB 0 ; base 31:24
%ifdef ARCH_X64
; linear code (64-bit) segment descriptor
LINEAR_CODE64_SEL equ $-GDT_BASE
DW 0xffff ; limit 15:0
DW 0 ; base 15:0
DB 0 ; base 23:16
DB PRESENT_FLAG(1)|DPL(0)|SYSTEM_FLAG(1)|DESC_TYPE(CODE64_TYPE)
DB GRANULARITY_FLAG(1)|DEFAULT_SIZE32(0)|CODE64_FLAG(1)|UPPER_LIMIT(0xf)
DB 0 ; base 31:24
%endif
GDT_END:

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@ -0,0 +1,149 @@
;------------------------------------------------------------------------------
; @file
; Sets the CR3 register for 64-bit paging
;
; Copyright (c) 2008 - 2013, Intel Corporation. All rights reserved.<BR>
; Copyright (c) 2019, Citrix Systems, Inc.
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
;------------------------------------------------------------------------------
BITS 32
%define PAGE_PRESENT 0x01
%define PAGE_READ_WRITE 0x02
%define PAGE_USER_SUPERVISOR 0x04
%define PAGE_WRITE_THROUGH 0x08
%define PAGE_CACHE_DISABLE 0x010
%define PAGE_ACCESSED 0x020
%define PAGE_DIRTY 0x040
%define PAGE_PAT 0x080
%define PAGE_GLOBAL 0x0100
%define PAGE_2M_MBO 0x080
%define PAGE_2M_PAT 0x01000
%define PAGE_2M_PDE_ATTR (PAGE_2M_MBO + \
PAGE_ACCESSED + \
PAGE_DIRTY + \
PAGE_READ_WRITE + \
PAGE_PRESENT)
%define PAGE_PDP_ATTR (PAGE_ACCESSED + \
PAGE_READ_WRITE + \
PAGE_PRESENT)
; Check if Secure Encrypted Virtualization (SEV) feature is enabled
;
; If SEV is enabled then EAX will be at least 32
; If SEV is disabled then EAX will be zero.
;
CheckSevFeature:
; Check if we have a valid (0x8000_001F) CPUID leaf
mov eax, 0x80000000
cpuid
; This check should fail on Intel or Non SEV AMD CPUs. In future if
; Intel CPUs supports this CPUID leaf then we are guranteed to have exact
; same bit definition.
cmp eax, 0x8000001f
jl NoSev
; Check for memory encryption feature:
; CPUID Fn8000_001F[EAX] - Bit 1
;
mov eax, 0x8000001f
cpuid
bt eax, 1
jnc NoSev
; Check if memory encryption is enabled
; MSR_0xC0010131 - Bit 0 (SEV enabled)
mov ecx, 0xc0010131
rdmsr
bt eax, 0
jnc NoSev
; Get pte bit position to enable memory encryption
; CPUID Fn8000_001F[EBX] - Bits 5:0
;
mov eax, ebx
and eax, 0x3f
jmp SevExit
NoSev:
xor eax, eax
SevExit:
OneTimeCallRet CheckSevFeature
;
; Modified: EAX, EBX, ECX, EDX
;
SetCr3ForPageTables64:
OneTimeCall CheckSevFeature
xor edx, edx
test eax, eax
jz SevNotActive
; If SEV is enabled, C-bit is always above 31
sub eax, 32
bts edx, eax
SevNotActive:
;
; For OVMF, build some initial page tables at
; PcdOvmfSecPageTablesBase - (PcdOvmfSecPageTablesBase + 0x6000).
;
; This range should match with PcdOvmfSecPageTablesSize which is
; declared in the FDF files.
;
; At the end of PEI, the pages tables will be rebuilt into a
; more permanent location by DxeIpl.
;
mov ecx, 6 * 0x1000 / 4
xor eax, eax
clearPageTablesMemoryLoop:
mov dword[ecx * 4 + PT_ADDR (0) - 4], eax
loop clearPageTablesMemoryLoop
;
; Top level Page Directory Pointers (1 * 512GB entry)
;
mov dword[PT_ADDR (0)], PT_ADDR (0x1000) + PAGE_PDP_ATTR
mov dword[PT_ADDR (4)], edx
;
; Next level Page Directory Pointers (4 * 1GB entries => 4GB)
;
mov dword[PT_ADDR (0x1000)], PT_ADDR (0x2000) + PAGE_PDP_ATTR
mov dword[PT_ADDR (0x1004)], edx
mov dword[PT_ADDR (0x1008)], PT_ADDR (0x3000) + PAGE_PDP_ATTR
mov dword[PT_ADDR (0x100C)], edx
mov dword[PT_ADDR (0x1010)], PT_ADDR (0x4000) + PAGE_PDP_ATTR
mov dword[PT_ADDR (0x1014)], edx
mov dword[PT_ADDR (0x1018)], PT_ADDR (0x5000) + PAGE_PDP_ATTR
mov dword[PT_ADDR (0x101C)], edx
;
; Page Table Entries (2048 * 2MB entries => 4GB)
;
mov ecx, 0x800
pageTableEntriesLoop:
mov eax, ecx
dec eax
shl eax, 21
add eax, PAGE_2M_PDE_ATTR
mov [ecx * 8 + PT_ADDR (0x2000 - 8)], eax
mov [(ecx * 8 + PT_ADDR (0x2000 - 8)) + 4], edx
loop pageTableEntriesLoop
;
; Set CR3 now that the paging structures are available
;
mov eax, PT_ADDR (0)
mov cr3, eax
OneTimeCallRet SetCr3ForPageTables64

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@ -0,0 +1,38 @@
## @file
# Reset Vector
#
# Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR>
# Copyright (c) 2019, Citrix Systems, Inc.
#
# SPDX-License-Identifier: BSD-2-Clause-Patent
#
##
[Defines]
INF_VERSION = 0x00010005
BASE_NAME = XenResetVector
FILE_GUID = 1BA0062E-C779-4582-8566-336AE8F78F09
MODULE_TYPE = SEC
VERSION_STRING = 1.1
#
# The following information is for reference only and not required by the build tools.
#
# VALID_ARCHITECTURES = IA32 X64
#
[Sources]
XenResetVector.nasmb
[Packages]
OvmfPkg/OvmfPkg.dec
MdePkg/MdePkg.dec
UefiCpuPkg/UefiCpuPkg.dec
[BuildOptions]
*_*_IA32_NASMB_FLAGS = -I$(WORKSPACE)/UefiCpuPkg/ResetVector/Vtf0/
*_*_X64_NASMB_FLAGS = -I$(WORKSPACE)/UefiCpuPkg/ResetVector/Vtf0/
[Pcd]
gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSecPageTablesBase
gUefiOvmfPkgTokenSpaceGuid.PcdOvmfSecPageTablesSize

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@ -0,0 +1,68 @@
;------------------------------------------------------------------------------
; @file
; This file includes all other code files to assemble the reset vector code
;
; Copyright (c) 2008 - 2013, Intel Corporation. All rights reserved.<BR>
; Copyright (c) 2019, Citrix Systems, Inc.
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
;------------------------------------------------------------------------------
;
; If neither ARCH_IA32 nor ARCH_X64 are defined, then try to include
; Base.h to use the C pre-processor to determine the architecture.
;
%ifndef ARCH_IA32
%ifndef ARCH_X64
#include <Base.h>
#if defined (MDE_CPU_IA32)
%define ARCH_IA32
#elif defined (MDE_CPU_X64)
%define ARCH_X64
#endif
%endif
%endif
%ifdef ARCH_IA32
%ifdef ARCH_X64
%error "Only one of ARCH_IA32 or ARCH_X64 can be defined."
%endif
%elifdef ARCH_X64
%else
%error "Either ARCH_IA32 or ARCH_X64 must be defined."
%endif
%include "CommonMacros.inc"
%include "PostCodes.inc"
%ifdef DEBUG_PORT80
%include "Port80Debug.asm"
%elifdef DEBUG_SERIAL
%include "SerialDebug.asm"
%else
%include "DebugDisabled.asm"
%endif
%include "Ia32/SearchForBfvBase.asm"
%include "Ia32/SearchForSecEntry.asm"
%ifdef ARCH_X64
#include <AutoGen.h>
%if (FixedPcdGet32 (PcdOvmfSecPageTablesSize) != 0x6000)
%error "This implementation inherently depends on PcdOvmfSecPageTablesSize"
%endif
%define PT_ADDR(Offset) (FixedPcdGet32 (PcdOvmfSecPageTablesBase) + (Offset))
%include "Ia32/Flat32ToFlat64.asm"
%include "Ia32/PageTables64.asm"
%endif
%include "Ia16/Real16ToFlat32.asm"
%include "Ia16/Init16.asm"
%include "Main.asm"
%include "Ia16/ResetVectorVtf0.asm"