1 /** @file
2   CPU exception handler library implemenation for SEC/PEIM modules.
3 
4 Copyright (c) 2012 - 2018, Intel Corporation. All rights reserved.<BR>
5 SPDX-License-Identifier: BSD-2-Clause-Patent
6 
7 **/
8 
9 #include <PiPei.h>
10 #include <Library/VmgExitLib.h>
11 #include "CpuExceptionCommon.h"
12 
13 CONST UINTN    mDoFarReturnFlag  = 0;
14 
15 /**
16   Common exception handler.
17 
18   @param ExceptionType  Exception type.
19   @param SystemContext  Pointer to EFI_SYSTEM_CONTEXT.
20 **/
21 VOID
22 EFIAPI
CommonExceptionHandler(IN EFI_EXCEPTION_TYPE ExceptionType,IN EFI_SYSTEM_CONTEXT SystemContext)23 CommonExceptionHandler (
24   IN EFI_EXCEPTION_TYPE   ExceptionType,
25   IN EFI_SYSTEM_CONTEXT   SystemContext
26   )
27 {
28   if (ExceptionType == VC_EXCEPTION) {
29     EFI_STATUS  Status;
30     //
31     // #VC needs to be handled immediately upon enabling exception handling
32     // and therefore can't use the RegisterCpuInterruptHandler() interface
33     // (which isn't supported under Sec and Pei anyway).
34     //
35     // Handle the #VC:
36     //   On EFI_SUCCESS - Exception has been handled, return
37     //   On other       - ExceptionType contains (possibly new) exception
38     //                    value
39     //
40     Status = VmgExitHandleVc (&ExceptionType, SystemContext);
41     if (!EFI_ERROR (Status)) {
42       return;
43     }
44   }
45 
46   //
47   // Initialize the serial port before dumping.
48   //
49   SerialPortInitialize ();
50   //
51   // Display ExceptionType, CPU information and Image information
52   //
53   DumpImageAndCpuContent (ExceptionType, SystemContext);
54 
55   //
56   // Enter a dead loop.
57   //
58   CpuDeadLoop ();
59 }
60 
61 /**
62   Initializes all CPU exceptions entries and provides the default exception handlers.
63 
64   Caller should try to get an array of interrupt and/or exception vectors that are in use and need to
65   persist by EFI_VECTOR_HANDOFF_INFO defined in PI 1.3 specification.
66   If caller cannot get reserved vector list or it does not exists, set VectorInfo to NULL.
67   If VectorInfo is not NULL, the exception vectors will be initialized per vector attribute accordingly.
68   Note: Before invoking this API, caller must allocate memory for IDT table and load
69         IDTR by AsmWriteIdtr().
70 
71   @param[in]  VectorInfo    Pointer to reserved vector list.
72 
73   @retval EFI_SUCCESS           CPU Exception Entries have been successfully initialized
74                                 with default exception handlers.
75   @retval EFI_INVALID_PARAMETER VectorInfo includes the invalid content if VectorInfo is not NULL.
76   @retval EFI_UNSUPPORTED       This function is not supported.
77 
78 **/
79 EFI_STATUS
80 EFIAPI
InitializeCpuExceptionHandlers(IN EFI_VECTOR_HANDOFF_INFO * VectorInfo OPTIONAL)81 InitializeCpuExceptionHandlers (
82   IN EFI_VECTOR_HANDOFF_INFO       *VectorInfo OPTIONAL
83   )
84 {
85   EFI_STATUS                       Status;
86   RESERVED_VECTORS_DATA            ReservedVectorData[CPU_EXCEPTION_NUM];
87   IA32_DESCRIPTOR                  IdtDescriptor;
88   UINTN                            IdtEntryCount;
89   UINT16                           CodeSegment;
90   EXCEPTION_HANDLER_TEMPLATE_MAP   TemplateMap;
91   IA32_IDT_GATE_DESCRIPTOR         *IdtTable;
92   UINTN                            Index;
93   UINTN                            InterruptHandler;
94 
95   if (VectorInfo != NULL) {
96     SetMem ((VOID *) ReservedVectorData, sizeof (RESERVED_VECTORS_DATA) * CPU_EXCEPTION_NUM, 0xff);
97     Status = ReadAndVerifyVectorInfo (VectorInfo, ReservedVectorData, CPU_EXCEPTION_NUM);
98     if (EFI_ERROR (Status)) {
99       return EFI_INVALID_PARAMETER;
100     }
101   }
102   //
103   // Read IDT descriptor and calculate IDT size
104   //
105   AsmReadIdtr (&IdtDescriptor);
106   IdtEntryCount = (IdtDescriptor.Limit + 1) / sizeof (IA32_IDT_GATE_DESCRIPTOR);
107   if (IdtEntryCount > CPU_EXCEPTION_NUM) {
108     //
109     // CPU exception library only setup CPU_EXCEPTION_NUM exception handler at most
110     //
111     IdtEntryCount = CPU_EXCEPTION_NUM;
112   }
113   //
114   // Use current CS as the segment selector of interrupt gate in IDT
115   //
116   CodeSegment = AsmReadCs ();
117 
118   AsmGetTemplateAddressMap (&TemplateMap);
119   IdtTable = (IA32_IDT_GATE_DESCRIPTOR *)IdtDescriptor.Base;
120   for (Index = 0; Index < IdtEntryCount; Index ++) {
121     IdtTable[Index].Bits.Selector = CodeSegment;
122     //
123     // Check reserved vectors attributes if has, only EFI_VECTOR_HANDOFF_DO_NOT_HOOK
124     // supported in this instance
125     //
126     if (VectorInfo != NULL) {
127       if (ReservedVectorData[Index].Attribute == EFI_VECTOR_HANDOFF_DO_NOT_HOOK) {
128         continue;
129       }
130     }
131     //
132     // Update IDT entry
133     //
134     InterruptHandler = TemplateMap.ExceptionStart + Index * TemplateMap.ExceptionStubHeaderSize;
135     ArchUpdateIdtEntry (&IdtTable[Index], InterruptHandler);
136   }
137   return EFI_SUCCESS;
138 }
139 
140 /**
141   Initializes all CPU interrupt/exceptions entries and provides the default interrupt/exception handlers.
142 
143   Caller should try to get an array of interrupt and/or exception vectors that are in use and need to
144   persist by EFI_VECTOR_HANDOFF_INFO defined in PI 1.3 specification.
145   If caller cannot get reserved vector list or it does not exists, set VectorInfo to NULL.
146   If VectorInfo is not NULL, the exception vectors will be initialized per vector attribute accordingly.
147 
148   @param[in]  VectorInfo    Pointer to reserved vector list.
149 
150   @retval EFI_SUCCESS           All CPU interrupt/exception entries have been successfully initialized
151                                 with default interrupt/exception handlers.
152   @retval EFI_INVALID_PARAMETER VectorInfo includes the invalid content if VectorInfo is not NULL.
153   @retval EFI_UNSUPPORTED       This function is not supported.
154 
155 **/
156 EFI_STATUS
157 EFIAPI
InitializeCpuInterruptHandlers(IN EFI_VECTOR_HANDOFF_INFO * VectorInfo OPTIONAL)158 InitializeCpuInterruptHandlers (
159   IN EFI_VECTOR_HANDOFF_INFO       *VectorInfo OPTIONAL
160   )
161 {
162   return EFI_UNSUPPORTED;
163 }
164 
165 /**
166   Registers a function to be called from the processor interrupt handler.
167 
168   This function registers and enables the handler specified by InterruptHandler for a processor
169   interrupt or exception type specified by InterruptType. If InterruptHandler is NULL, then the
170   handler for the processor interrupt or exception type specified by InterruptType is uninstalled.
171   The installed handler is called once for each processor interrupt or exception.
172   NOTE: This function should be invoked after InitializeCpuExceptionHandlers() or
173   InitializeCpuInterruptHandlers() invoked, otherwise EFI_UNSUPPORTED returned.
174 
175   @param[in]  InterruptType     Defines which interrupt or exception to hook.
176   @param[in]  InterruptHandler  A pointer to a function of type EFI_CPU_INTERRUPT_HANDLER that is called
177                                 when a processor interrupt occurs. If this parameter is NULL, then the handler
178                                 will be uninstalled.
179 
180   @retval EFI_SUCCESS           The handler for the processor interrupt was successfully installed or uninstalled.
181   @retval EFI_ALREADY_STARTED   InterruptHandler is not NULL, and a handler for InterruptType was
182                                 previously installed.
183   @retval EFI_INVALID_PARAMETER InterruptHandler is NULL, and a handler for InterruptType was not
184                                 previously installed.
185   @retval EFI_UNSUPPORTED       The interrupt specified by InterruptType is not supported,
186                                 or this function is not supported.
187 **/
188 EFI_STATUS
189 EFIAPI
RegisterCpuInterruptHandler(IN EFI_EXCEPTION_TYPE InterruptType,IN EFI_CPU_INTERRUPT_HANDLER InterruptHandler)190 RegisterCpuInterruptHandler (
191   IN EFI_EXCEPTION_TYPE            InterruptType,
192   IN EFI_CPU_INTERRUPT_HANDLER     InterruptHandler
193   )
194 {
195   return EFI_UNSUPPORTED;
196 }
197 
198 /**
199   Initializes all CPU exceptions entries with optional extra initializations.
200 
201   By default, this method should include all functionalities implemented by
202   InitializeCpuExceptionHandlers(), plus extra initialization works, if any.
203   This could be done by calling InitializeCpuExceptionHandlers() directly
204   in this method besides the extra works.
205 
206   InitData is optional and its use and content are processor arch dependent.
207   The typical usage of it is to convey resources which have to be reserved
208   elsewhere and are necessary for the extra initializations of exception.
209 
210   @param[in]  VectorInfo    Pointer to reserved vector list.
211   @param[in]  InitData      Pointer to data optional for extra initializations
212                             of exception.
213 
214   @retval EFI_SUCCESS             The exceptions have been successfully
215                                   initialized.
216   @retval EFI_INVALID_PARAMETER   VectorInfo or InitData contains invalid
217                                   content.
218 
219 **/
220 EFI_STATUS
221 EFIAPI
InitializeCpuExceptionHandlersEx(IN EFI_VECTOR_HANDOFF_INFO * VectorInfo OPTIONAL,IN CPU_EXCEPTION_INIT_DATA * InitData OPTIONAL)222 InitializeCpuExceptionHandlersEx (
223   IN EFI_VECTOR_HANDOFF_INFO            *VectorInfo OPTIONAL,
224   IN CPU_EXCEPTION_INIT_DATA            *InitData OPTIONAL
225   )
226 {
227   return InitializeCpuExceptionHandlers (VectorInfo);
228 }
229