30 lines
1.1 KiB
Plaintext
30 lines
1.1 KiB
Plaintext
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The AMD64 kernel is loaded with an X86 loader. This is to enable a single
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loader to dual-boot either an i386 or Amd64 build. The remainder of this
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text refers to only the i386 version of the loader.
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There are two new AMD64-specific exports in boot.lib:
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ARC_STATUS
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BlAmd64CheckForLongMode(
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IN ULONG LoadDeviceId,
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IN OUT PCHAR KernelPath,
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IN PCHAR KernelFileName
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);
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extern BOOLEAN BlAmd64UseLongMode;
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BlAmd64CheckForLongMode() is called from the loader. If an AMD64 kernel
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image is found, then the global BlAmd64UseLongMode is set to TRUE. From
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this point forward, all images are expected to be AMD64 images.
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Almost all of the code specific to AMD64 support is found in
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boot\lib\amd64. At present, the contents of this directory is available to
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only a few people. However the loader, obviously, must build for
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everybody.
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To facilitate this, _X86AMD64_ is defined while building the boot\lib
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directory if files within the amd64 directory are present on the build
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machine. If they are not present, then a stub version of
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BlAmd64CheckForLongMode() is created.
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