remove unnecessary comments introduced by tools from MdePkg. The regular express...

[mirror_edk2.git] / MdePkg / Library / BaseLib / Ia32 / EnablePaging32.c

diff --git a/MdePkg/Library/BaseLib/Ia32/EnablePaging32.c b/MdePkg/Library/BaseLib/Ia32/EnablePaging32.c
index 7aecd0179039604411d5a2d56d94e31257214704..8d963e15d0c32fae26588ff8a5b2e266e6c58df2 100644 (file)
--- a/MdePkg/Library/BaseLib/Ia32/EnablePaging32.c
+++ b/MdePkg/Library/BaseLib/Ia32/EnablePaging32.c
@@ -12,6 +12,44 @@
 \r
 **/\r
 \r
+\r
+#include <BaseLibInternals.h>\r
+\r
+#if _MSC_EXTENSIONS\r
+\r
+/**\r
+  Enables the 32-bit paging mode on the CPU.\r
+\r
+  Enables the 32-bit paging mode on the CPU. CR0, CR3, CR4, and the page tables\r
+  must be properly initialized prior to calling this service. This function\r
+  assumes the current execution mode is 32-bit protected mode. This function is\r
+  only available on IA-32. After the 32-bit paging mode is enabled, control is\r
+  transferred to the function specified by EntryPoint using the new stack\r
+  specified by NewStack and passing in the parameters specified by Context1 and\r
+  Context2. Context1 and Context2 are optional and may be NULL. The function\r
+  EntryPoint must never return.\r
+\r
+  There are a number of constraints that must be followed before calling this\r
+  function:\r
+  1)  Interrupts must be disabled.\r
+  2)  The caller must be in 32-bit protected mode with flat descriptors. This\r
+      means all descriptors must have a base of 0 and a limit of 4GB.\r
+  3)  CR0 and CR4 must be compatible with 32-bit protected mode with flat\r
+      descriptors.\r
+  4)  CR3 must point to valid page tables that will be used once the transition\r
+      is complete, and those page tables must guarantee that the pages for this\r
+      function and the stack are identity mapped.\r
+\r
+  @param  EntryPoint  A pointer to function to call with the new stack after\r
+                      paging is enabled.\r
+  @param  Context1    A pointer to the context to pass into the EntryPoint\r
+                      function as the first parameter after paging is enabled.\r
+  @param  Context2    A pointer to the context to pass into the EntryPoint\r
+                      function as the second parameter after paging is enabled.\r
+  @param  NewStack    A pointer to the new stack to use for the EntryPoint\r
+                      function after paging is enabled.\r
+\r
+**/\r
 __declspec (naked)\r
 VOID\r
 EFIAPI\r
@@ -44,3 +82,4 @@ InternalX86EnablePaging32 (
   }\r
 }\r
 \r
+#endif\r