1/** @file
2A driver allocates common SMM communication buffer in EfiReservedMemoryType.
3
4This driver allocates common SMM communication buffer in EfiReservedMemoryType,
5then it publishes the information to EFI configuration table with
6gEdkiiPiSmmCommunicationRegionTableGuid.
7Any other driver or application can get the table and know the common
8communication buffer.
9
10Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
11This program and the accompanying materials
12are licensed and made available under the terms and conditions of the BSD License
13which accompanies this distribution.  The full text of the license may be found at
14http://opensource.org/licenses/bsd-license.php
15
16THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
17WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
18
19**/
20
21#include <PiDxe.h>
22#include <Library/UefiBootServicesTableLib.h>
23#include <Library/UefiRuntimeServicesTableLib.h>
24#include <Library/BaseLib.h>
25#include <Library/BaseMemoryLib.h>
26#include <Library/MemoryAllocationLib.h>
27#include <Library/DebugLib.h>
28#include <Library/UefiLib.h>
29#include <Library/PcdLib.h>
30#include <Guid/PiSmmCommunicationRegionTable.h>
31
32#define DEFAULT_COMMON_PI_SMM_COMMUNIATION_REGION_PAGES  4
33
34/**
35  Entry Point for SMM communication buffer driver.
36
37  @param[in] ImageHandle  Image handle of this driver.
38  @param[in] SystemTable  A Pointer to the EFI System Table.
39
40  @retval EFI_SUCEESS
41  @return Others          Some error occurs.
42**/
43EFI_STATUS
44EFIAPI
45SmmCommunicationBufferEntryPoint (
46  IN EFI_HANDLE        ImageHandle,
47  IN EFI_SYSTEM_TABLE  *SystemTable
48  )
49{
50  EFI_STATUS                               Status;
51  UINT32                                   DescriptorSize;
52  EDKII_PI_SMM_COMMUNICATION_REGION_TABLE  *PiSmmCommunicationRegionTable;
53  EFI_MEMORY_DESCRIPTOR                    *Entry;
54
55  DescriptorSize = sizeof(EFI_MEMORY_DESCRIPTOR);
56  //
57  // Make sure Size != sizeof(EFI_MEMORY_DESCRIPTOR). This will
58  // prevent people from having pointer math bugs in their code.
59  // now you have to use *DescriptorSize to make things work.
60  //
61  DescriptorSize += sizeof(UINT64) - (DescriptorSize % sizeof (UINT64));
62
63  //
64  // Allocate and fill PiSmmCommunicationRegionTable
65  //
66  PiSmmCommunicationRegionTable = AllocateReservedPool (sizeof(EDKII_PI_SMM_COMMUNICATION_REGION_TABLE) + DescriptorSize);
67  ASSERT(PiSmmCommunicationRegionTable != NULL);
68  ZeroMem (PiSmmCommunicationRegionTable, sizeof(EDKII_PI_SMM_COMMUNICATION_REGION_TABLE) + DescriptorSize);
69
70  PiSmmCommunicationRegionTable->Version         = EDKII_PI_SMM_COMMUNICATION_REGION_TABLE_VERSION;
71  PiSmmCommunicationRegionTable->NumberOfEntries = 1;
72  PiSmmCommunicationRegionTable->DescriptorSize  = DescriptorSize;
73  Entry = (EFI_MEMORY_DESCRIPTOR *)(PiSmmCommunicationRegionTable + 1);
74  Entry->Type          = EfiConventionalMemory;
75  Entry->PhysicalStart = (EFI_PHYSICAL_ADDRESS)(UINTN)AllocateReservedPages (DEFAULT_COMMON_PI_SMM_COMMUNIATION_REGION_PAGES);
76  ASSERT(Entry->PhysicalStart != 0);
77  Entry->VirtualStart  = 0;
78  Entry->NumberOfPages = DEFAULT_COMMON_PI_SMM_COMMUNIATION_REGION_PAGES;
79  Entry->Attribute     = 0;
80
81  DEBUG ((EFI_D_INFO, "PiSmmCommunicationRegionTable:(0x%x)\n", PiSmmCommunicationRegionTable));
82  DEBUG ((EFI_D_INFO, "  Version         - 0x%x\n", PiSmmCommunicationRegionTable->Version));
83  DEBUG ((EFI_D_INFO, "  NumberOfEntries - 0x%x\n", PiSmmCommunicationRegionTable->NumberOfEntries));
84  DEBUG ((EFI_D_INFO, "  DescriptorSize  - 0x%x\n", PiSmmCommunicationRegionTable->DescriptorSize));
85  DEBUG ((EFI_D_INFO, "Entry:(0x%x)\n", Entry));
86  DEBUG ((EFI_D_INFO, "  Type            - 0x%x\n", Entry->Type));
87  DEBUG ((EFI_D_INFO, "  PhysicalStart   - 0x%lx\n", Entry->PhysicalStart));
88  DEBUG ((EFI_D_INFO, "  VirtualStart    - 0x%lx\n", Entry->VirtualStart));
89  DEBUG ((EFI_D_INFO, "  NumberOfPages   - 0x%lx\n", Entry->NumberOfPages));
90  DEBUG ((EFI_D_INFO, "  Attribute       - 0x%lx\n", Entry->Attribute));
91
92  //
93  // Publish this table, so that other driver can use the buffer.
94  //
95  Status = gBS->InstallConfigurationTable (&gEdkiiPiSmmCommunicationRegionTableGuid, PiSmmCommunicationRegionTable);
96  ASSERT_EFI_ERROR (Status);
97
98  return Status;
99}
100