15 lines
566 B
Markdown
15 lines
566 B
Markdown
# ACPI SSDT \_UID generation
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According to the ACPI spec:
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> The _UID must be unique across all devices with either a common _HID or _CID.
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When generating SSDTs in coreboot the independent drivers don't know
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which \_UID is already in use for a specific \_HID or \_CID. To generate
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unique \_UIDs the ACPI device's path is hashed and used as ID. As every ACPI
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device has a different path, the hash will be also different for every device.
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Windows 10 verifies all devices with the same \_HID or \_CID and makes
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sure that no \_UID is duplicated. If it is it'll BSOD.
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