xref: /linux/Documentation/driver-api/cxl/platform/acpi/dsdt.rst (revision e9ef810dfee7a2227da9d423aecb0ced35faddbe)
1*d1ba3646SGregory Price.. SPDX-License-Identifier: GPL-2.0
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3*d1ba3646SGregory Price==============================================
4*d1ba3646SGregory PriceDSDT - Differentiated system Description Table
5*d1ba3646SGregory Price==============================================
6*d1ba3646SGregory Price
7*d1ba3646SGregory PriceThis table describes what peripherals a machine has.
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9*d1ba3646SGregory PriceThis table's UIDs for CXL devices - specifically host bridges, must be
10*d1ba3646SGregory Priceconsistent with the contents of the CEDT, otherwise the CXL driver will
11*d1ba3646SGregory Pricefail to probe correctly.
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13*d1ba3646SGregory PriceExample Compute Express Link Host Bridge ::
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15*d1ba3646SGregory Price    Scope (_SB)
16*d1ba3646SGregory Price    {
17*d1ba3646SGregory Price        Device (S0D0)
18*d1ba3646SGregory Price        {
19*d1ba3646SGregory Price            Name (_HID, "ACPI0016" /* Compute Express Link Host Bridge */)  // _HID: Hardware ID
20*d1ba3646SGregory Price            Name (_CID, Package (0x02)  // _CID: Compatible ID
21*d1ba3646SGregory Price            {
22*d1ba3646SGregory Price                EisaId ("PNP0A08") /* PCI Express Bus */,
23*d1ba3646SGregory Price                EisaId ("PNP0A03") /* PCI Bus */
24*d1ba3646SGregory Price            })
25*d1ba3646SGregory Price            ...
26*d1ba3646SGregory Price            Name (_UID, 0x05)  // _UID: Unique ID
27*d1ba3646SGregory Price            ...
28*d1ba3646SGregory Price      }
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