2 IA32 specific debug support functions
4 Copyright (c) 2006 - 2007, Intel Corporation
5 All rights reserved. This program and the accompanying materials
6 are licensed and made available under the terms and conditions of the BSD License
7 which accompanies this distribution. The full text of the license may be found at
8 http://opensource.org/licenses/bsd-license.php
10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
16 // private header files
18 #include "plDebugSupport.h"
21 // This the global main table to keep track of the interrupts
23 IDT_ENTRY
*IdtEntryTable
= NULL
;
24 DESCRIPTOR NullDesc
= 0;
29 IN EFI_EXCEPTION_TYPE ExceptionType
,
34 Routine Description: Allocate pool for a new IDT entry stub. Copy the generic
35 stub into the new buffer and fixup the vector number and jump target address.
38 ExceptionType - This is the exception type that the new stub will be created
40 Stub - On successful exit, *Stub contains the newly allocated entry stub.
43 other possibilities are passed through from AllocatePool
52 // Fixup the stub code for this vector
55 // The stub code looks like this:
57 // 00000000 89 25 00000004 R mov AppEsp, esp ; save stack top
58 // 00000006 BC 00008014 R mov esp, offset DbgStkBot ; switch to debugger stack
59 // 0000000B 6A 00 push 0 ; push vector number - will be modified before installed
60 // 0000000D E9 db 0e9h ; jump rel32
61 // 0000000E 00000000 dd 0 ; fixed up to relative address of CommonIdtEntry
65 // poke in the exception type so the second push pushes the exception type
67 StubCopy
[0x0c] = (UINT8
) ExceptionType
;
70 // fixup the jump target to point to the common entry
72 *(UINT32
*) &StubCopy
[0x0e] = (UINT32
) CommonIdtEntry
- (UINT32
) &StubCopy
[StubSize
];
80 IN EFI_EXCEPTION_TYPE ExceptionType
,
81 IN
VOID (*NewCallback
) ()
86 Creates a nes entry stub. Then saves the current IDT entry and replaces it
87 with an interrupt gate for the new entry point. The IdtEntryTable is updated
88 with the new registered function.
90 This code executes in boot services context. The stub entry executes in interrupt
94 ExceptionType - specifies which vector to hook.
95 NewCallback - a pointer to the new function to be registered.
99 Other possibilities are passed through by CreateEntryStub
103 BOOLEAN OldIntFlagState
;
106 Status
= CreateEntryStub (ExceptionType
, (VOID
**) &IdtEntryTable
[ExceptionType
].StubEntry
);
107 if (Status
== EFI_SUCCESS
) {
108 OldIntFlagState
= WriteInterruptFlag (0);
109 ReadIdt (ExceptionType
, &(IdtEntryTable
[ExceptionType
].OrigDesc
));
111 ((UINT16
*) &IdtEntryTable
[ExceptionType
].OrigVector
)[0] = ((UINT16
*) &IdtEntryTable
[ExceptionType
].OrigDesc
)[0];
112 ((UINT16
*) &IdtEntryTable
[ExceptionType
].OrigVector
)[1] = ((UINT16
*) &IdtEntryTable
[ExceptionType
].OrigDesc
)[3];
114 Vect2Desc (&IdtEntryTable
[ExceptionType
].NewDesc
, IdtEntryTable
[ExceptionType
].StubEntry
);
115 IdtEntryTable
[ExceptionType
].RegisteredCallback
= NewCallback
;
116 WriteIdt (ExceptionType
, &(IdtEntryTable
[ExceptionType
].NewDesc
));
117 WriteInterruptFlag (OldIntFlagState
);
126 IN EFI_EXCEPTION_TYPE ExceptionType
131 Undoes HookEntry. This code executes in boot services context.
134 ExceptionType - specifies which entry to unhook
141 BOOLEAN OldIntFlagState
;
143 OldIntFlagState
= WriteInterruptFlag (0);
144 WriteIdt (ExceptionType
, &(IdtEntryTable
[ExceptionType
].OrigDesc
));
145 WriteInterruptFlag (OldIntFlagState
);
151 ManageIdtEntryTable (
152 VOID (*NewCallback
)(),
153 EFI_EXCEPTION_TYPE ExceptionType
158 This is the main worker function that manages the state of the interrupt
159 handlers. It both installs and uninstalls interrupt handlers based on the
160 value of NewCallback. If NewCallback is NULL, then uninstall is indicated.
161 If NewCallback is non-NULL, then install is indicated.
164 NewCallback - If non-NULL, NewCallback specifies the new handler to register.
165 If NULL, specifies that the previously registered handler should
167 ExceptionType - Indicates which entry to manage
171 EFI_INVALID_PARAMETER - requested uninstalling a handler from a vector that has
172 no handler registered for it
173 EFI_ALREADY_STARTED - requested install to a vector that already has a handler registered.
175 Other possible return values are passed through from UnHookEntry and HookEntry.
181 Status
= EFI_SUCCESS
;
183 if (FeaturePcdGet (PcdNtEmulatorEnable
)) {
184 if (CompareDescriptor (&IdtEntryTable
[ExceptionType
].NewDesc
, &NullDesc
)) {
186 // we've already installed to this vector
188 if (NewCallback
!= NULL
) {
190 // if the input handler is non-null, error
192 Status
= EFI_ALREADY_STARTED
;
194 Status
= UnhookEntry (ExceptionType
);
198 // no user handler installed on this vector
200 if (NewCallback
== NULL
) {
202 // if the input handler is null, error
204 Status
= EFI_INVALID_PARAMETER
;
206 Status
= HookEntry (ExceptionType
, NewCallback
);
216 GetMaximumProcessorIndex (
217 IN EFI_DEBUG_SUPPORT_PROTOCOL
*This
,
218 OUT UINTN
*MaxProcessorIndex
222 Routine Description: This is a DebugSupport protocol member function.
225 This - The DebugSupport instance
226 MaxProcessorIndex - The maximuim supported processor index
229 Always returns EFI_SUCCESS with *MaxProcessorIndex set to 0
233 *MaxProcessorIndex
= 0;
234 return (EFI_SUCCESS
);
239 RegisterPeriodicCallback (
240 IN EFI_DEBUG_SUPPORT_PROTOCOL
*This
,
241 IN UINTN ProcessorIndex
,
242 IN EFI_PERIODIC_CALLBACK PeriodicCallback
246 Routine Description: This is a DebugSupport protocol member function.
249 This - The DebugSupport instance
250 ProcessorIndex - Which processor the callback applies to.
251 PeriodicCallback - Callback function
256 EFI_INVALID_PARAMETER - requested uninstalling a handler from a vector that has
257 no handler registered for it
258 EFI_ALREADY_STARTED - requested install to a vector that already has a handler registered.
260 Other possible return values are passed through from UnHookEntry and HookEntry.
264 return ManageIdtEntryTable (PeriodicCallback
, SYSTEM_TIMER_VECTOR
);
269 RegisterExceptionCallback (
270 IN EFI_DEBUG_SUPPORT_PROTOCOL
*This
,
271 IN UINTN ProcessorIndex
,
272 IN EFI_EXCEPTION_CALLBACK NewCallback
,
273 IN EFI_EXCEPTION_TYPE ExceptionType
278 This is a DebugSupport protocol member function.
280 This code executes in boot services context.
283 This - The DebugSupport instance
284 ProcessorIndex - Which processor the callback applies to.
285 NewCallback - Callback function
286 ExceptionType - Which exception to hook
291 EFI_INVALID_PARAMETER - requested uninstalling a handler from a vector that has
292 no handler registered for it
293 EFI_ALREADY_STARTED - requested install to a vector that already has a handler registered.
295 Other possible return values are passed through from UnHookEntry and HookEntry.
299 return ManageIdtEntryTable (NewCallback
, ExceptionType
);
304 InvalidateInstructionCache (
305 IN EFI_DEBUG_SUPPORT_PROTOCOL
*This
,
306 IN UINTN ProcessorIndex
,
313 This is a DebugSupport protocol member function.
314 Calls assembly routine to flush cache.
317 This - The DebugSupport instance
318 ProcessorIndex - Which processor the callback applies to.
319 Start - Physical base of the memory range to be invalidated
320 Length - mininum number of bytes in instruction cache to invalidate
324 EFI_SUCCESS - always return success
333 plInitializeDebugSupportDriver (
339 Initializes driver's handler registration database.
341 This code executes in boot services context.
348 EFI_UNSUPPORTED - if IA32 processor does not support FXSTOR/FXRSTOR instructions,
349 the context save will fail, so these processor's are not supported.
350 EFI_OUT_OF_RESOURCES - not resource to finish initialization
354 EFI_EXCEPTION_TYPE ExceptionType
;
356 if (!FxStorSupport ()) {
357 return EFI_UNSUPPORTED
;
360 IdtEntryTable
= AllocateZeroPool (sizeof (IDT_ENTRY
) * NUM_IDT_ENTRIES
);
361 if (IdtEntryTable
== NULL
) {
362 return EFI_OUT_OF_RESOURCES
;
365 for (ExceptionType
= 0; ExceptionType
< NUM_IDT_ENTRIES
; ExceptionType
++) {
366 IdtEntryTable
[ExceptionType
].StubEntry
= (DEBUG_PROC
) (UINTN
) AllocatePool (StubSize
);
367 if (IdtEntryTable
[ExceptionType
].StubEntry
== NULL
) {
371 CopyMem ((VOID
*)(UINTN
)IdtEntryTable
[ExceptionType
].StubEntry
, InterruptEntryStub
, StubSize
);
377 for (ExceptionType
= 0; ExceptionType
< NUM_IDT_ENTRIES
; ExceptionType
++) {
378 if (IdtEntryTable
[ExceptionType
].StubEntry
!= NULL
) {
379 FreePool ((VOID
*)(UINTN
)IdtEntryTable
[ExceptionType
].StubEntry
);
382 FreePool (IdtEntryTable
);
384 return EFI_OUT_OF_RESOURCES
;
389 plUnloadDebugSupportDriver (
390 IN EFI_HANDLE ImageHandle
395 This is the callback that is written to the LoadedImage protocol instance
396 on the image handle. It uninstalls all registered handlers and frees all entry
399 This code executes in boot services context.
402 ImageHandle - The image handle of the unload handler
406 EFI_SUCCESS - always return success
410 EFI_EXCEPTION_TYPE ExceptionType
;
412 for (ExceptionType
= 0; ExceptionType
< NUM_IDT_ENTRIES
; ExceptionType
++) {
413 ManageIdtEntryTable (NULL
, ExceptionType
);
416 FreePool (IdtEntryTable
);
421 InterruptDistrubutionHub (
422 EFI_EXCEPTION_TYPE ExceptionType
,
423 EFI_SYSTEM_CONTEXT_IA32
*ContextRecord
427 Routine Description: Common piece of code that invokes the registered handlers.
429 This code executes in exception context so no efi calls are allowed.
432 ExceptionType - exception type
433 ContextRecord - system context
441 if (IdtEntryTable
[ExceptionType
].RegisteredCallback
!= NULL
) {
442 if (ExceptionType
!= SYSTEM_TIMER_VECTOR
) {
443 IdtEntryTable
[ExceptionType
].RegisteredCallback (ExceptionType
, ContextRecord
);
445 OrigVector
= IdtEntryTable
[ExceptionType
].OrigVector
;
446 IdtEntryTable
[ExceptionType
].RegisteredCallback (ContextRecord
);