3 Copyright (c) 2006, Intel Corporation
4 All rights reserved. This program and the accompanying materials
5 are licensed and made available under the terms and conditions of the BSD License
6 which accompanies this distribution. The full text of the license may be found at
7 http://opensource.org/licenses/bsd-license.php
9 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
10 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
18 Ia32-specifc functionality for DxeLoad.
23 #include "VirtualMemory.h"
26 // Global Descriptor Table (GDT)
28 GLOBAL_REMOVE_IF_UNREFERENCED IA32_GDT gGdtEntries
[] = {
29 /* selector { Global Segment Descriptor } */
30 /* 0x00 */ {{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}}, //null descriptor
31 /* 0x08 */ {{0xffff, 0, 0, 0x2, 1, 0, 1, 0xf, 0, 0, 1, 1, 0}}, //linear data segment descriptor
32 /* 0x10 */ {{0xffff, 0, 0, 0xf, 1, 0, 1, 0xf, 0, 0, 1, 1, 0}}, //linear code segment descriptor
33 /* 0x18 */ {{0xffff, 0, 0, 0x3, 1, 0, 1, 0xf, 0, 0, 1, 1, 0}}, //system data segment descriptor
34 /* 0x20 */ {{0xffff, 0, 0, 0xa, 1, 0, 1, 0xf, 0, 0, 1, 1, 0}}, //system code segment descriptor
35 /* 0x28 */ {{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}}, //spare segment descriptor
36 /* 0x30 */ {{0xffff, 0, 0, 0x2, 1, 0, 1, 0xf, 0, 0, 1, 1, 0}}, //system data segment descriptor
37 /* 0x38 */ {{0xffff, 0, 0, 0xa, 1, 0, 1, 0xf, 0, 1, 0, 1, 0}}, //system code segment descriptor
38 /* 0x40 */ {{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}}, //spare segment descriptor
44 GLOBAL_REMOVE_IF_UNREFERENCED CONST IA32_DESCRIPTOR gGdt
= {
45 sizeof (gGdtEntries
) - 1,
51 IN EFI_PHYSICAL_ADDRESS DxeCoreEntryPoint
,
52 IN EFI_PEI_HOB_POINTERS HobList
,
53 IN EFI_PEI_PPI_DESCRIPTOR
*EndOfPeiSignal
57 EFI_PHYSICAL_ADDRESS BaseOfStack
;
58 EFI_PHYSICAL_ADDRESS TopOfStack
;
61 Status
= PeiServicesAllocatePages (EfiBootServicesData
, EFI_SIZE_TO_PAGES (STACK_SIZE
), &BaseOfStack
);
62 ASSERT_EFI_ERROR (Status
);
64 if (FeaturePcdGet(PcdDxeIplSwitchToLongMode
)) {
66 // Compute the top of the stack we were allocated, which is used to load X64 dxe core.
67 // Pre-allocate a 32 bytes which confroms to x64 calling convention.
69 // The first four parameters to a function are passed in rcx, rdx, r8 and r9.
70 // Any further parameters are pushed on the stack. Furthermore, space (4 * 8bytes) for the
71 // register parameters is reserved on the stack, in case the called function
72 // wants to spill them; this is important if the function is variadic.
74 TopOfStack
= BaseOfStack
+ EFI_SIZE_TO_PAGES (STACK_SIZE
) * EFI_PAGE_SIZE
- 32;
77 // X64 Calling Conventions requires that the stack must be aligned to 16 bytes
79 TopOfStack
= (EFI_PHYSICAL_ADDRESS
) (UINTN
) ALIGN_POINTER (TopOfStack
, 16);
82 // Load the GDT of Go64. Since the GDT of 32-bit Tiano locates in the BS_DATA
83 // memory, it may be corrupted when copying FV to high-end memory
87 // Create page table and save PageMapLevel4 to CR3
89 PageTables
= CreateIdentityMappingPageTables ();
92 // End of PEI phase singal
94 Status
= PeiServicesInstallPpi (EndOfPeiSignal
);
95 ASSERT_EFI_ERROR (Status
);
97 AsmWriteCr3 (PageTables
);
99 // Go to Long Mode. Interrupts will not get turned on until the CPU AP is loaded.
100 // Call x64 drivers passing in single argument, a pointer to the HOBs.
105 (EFI_PHYSICAL_ADDRESS
)(UINTN
)(HobList
.Raw
),
111 // Compute the top of the stack we were allocated. Pre-allocate a UINTN
114 TopOfStack
= BaseOfStack
+ EFI_SIZE_TO_PAGES (STACK_SIZE
) * EFI_PAGE_SIZE
- CPU_STACK_ALIGNMENT
;
115 TopOfStack
= (EFI_PHYSICAL_ADDRESS
) (UINTN
) ALIGN_POINTER (TopOfStack
, CPU_STACK_ALIGNMENT
);
118 // End of PEI phase singal
120 Status
= PeiServicesInstallPpi (EndOfPeiSignal
);
121 ASSERT_EFI_ERROR (Status
);
124 (SWITCH_STACK_ENTRY_POINT
)(UINTN
)DxeCoreEntryPoint
,
127 (VOID
*) (UINTN
) TopOfStack