Documentation/driver-api/cxl/platform/example-configurations/flexible.rst

Source file repositories/reference/linux-study-clean/Documentation/driver-api/cxl/platform/example-configurations/flexible.rst

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Linux kernel
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Documentation/driver-api/cxl/platform/example-configurations/flexible.rst
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.rst
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Support Tooling And Documentation
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Documentation
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Support Tooling And Documentation: documentation
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Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

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.. SPDX-License-Identifier: GPL-2.0

=====================
Flexible Presentation
=====================
This system has a single socket with two CXL host bridges. Each host bridge
has two CXL memory expanders with a 4GB of memory (32GB total).

On this system, the platform designer wanted to provide the user flexibility
to configure the memory devices in various interleave or NUMA node
configurations.  So they provided every combination.

Things to note:

* Cross-Bridge interleave is described in one CFMWS that covers all capacity.
* One CFMWS is also described per-host bridge.
* One CFMWS is also described per-device.
* This SRAT describes one node for each of the above CFMWS.
* The HMAT describes performance for each node in the SRAT.

:doc:`CEDT <../acpi/cedt>`::

            Subtable Type : 00 [CXL Host Bridge Structure]
                 Reserved : 00
                   Length : 0020
   Associated host bridge : 00000007
    Specification version : 00000001
                 Reserved : 00000000
            Register base : 0000010370400000
          Register length : 0000000000010000

            Subtable Type : 00 [CXL Host Bridge Structure]
                 Reserved : 00
                   Length : 0020
   Associated host bridge : 00000006
    Specification version : 00000001
                 Reserved : 00000000
            Register base : 0000010380800000
          Register length : 0000000000010000

            Subtable Type : 01 [CXL Fixed Memory Window Structure]
                 Reserved : 00
                   Length : 002C
                 Reserved : 00000000
      Window base address : 0000001000000000
              Window size : 0000000400000000
 Interleave Members (2^n) : 01
    Interleave Arithmetic : 00
                 Reserved : 0000
              Granularity : 00000000
             Restrictions : 0006
                    QtgId : 0001
             First Target : 00000007
            Second Target : 00000006

            Subtable Type : 01 [CXL Fixed Memory Window Structure]
                 Reserved : 00
                   Length : 002C
                 Reserved : 00000000
      Window base address : 0000002000000000
              Window size : 0000000200000000
 Interleave Members (2^n) : 00
    Interleave Arithmetic : 00
                 Reserved : 0000
              Granularity : 00000000
             Restrictions : 0006
                    QtgId : 0001
             First Target : 00000007

            Subtable Type : 01 [CXL Fixed Memory Window Structure]

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