[ANNOUNCE] x86-cpuid-db: Release v2.0

[Ahmed S. Darwish]

Hi,

I'm happy to announce release 2.0 of the x86-cpuid-db project:

  https://gitlab.com/x86-cpuid.org/x86-cpuid-db
  https://gitlab.com/x86-cpuid.org/x86-cpuid-db/-/releases/v2.0

Changelog v2.0
--------------

- Introduce a new transformer, which generates one Linux kernel C header
  file for all the cpuid leaves' bitfields.

  (A single linux kernel C header file, with version tag on top, shall be
   easier to maintain than multiple headers; Linux x86 PQ pending)

- Introduce the cpuidgen --kheaders option to invoke that transformer.

- Extend the cpuid database bitfields coverage:

  - Add Transmeta vendor tags to the appropriate bitfields at leaves
    0x0, 0x01, and from leaves 0x80000000 to 0x80000006.

  - Add the Transmeta-specific CPUID leaves 0x03, and 0x80860000 to
    0x80860007.

  - Add Centaur/Zhaoxin leaves 0xc0000000 and 0xc0000001, along with
    Zhoaxin's exclusive feature bits.

- Add some documentation in the schema for the <linux> annotation tag.

CPUID bitfields coverage
~~~~~~~~~~~~~~~~~~~~~~~~

In total, this release increases the x86-cpuid database bitfield
coverage to:

    CPUID leaves:        63 leaves
    CPUID bitfields:     907 entries

Changes to generated files styling
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Beside the new cpuid leaves and bitfields, the generated Linux kernel C
structures has changed from:

    /*
     * CPUID leaf 0
     */

    struct leaf0_sl0 {
        ...;
    };

    /*
     * CPUID leaf 7
     */

    struct leaf7_sl0 {
        ...;
    };

    struct leaf7_sl1 {
        ...;
    };

to:

    /*
     * Leaf 0x0
     * Maximum standard leaf number + CPU vendor string
     */

    struct leaf_0x0_0 {
        ...;
    };

    /*
     * Leaf 0x7
     * Extended CPU features enumeration
     */

    struct leaf_0x7_0 {
        ...;
    };

    struct leaf_0x7_1 {
        ...;
    };

Overall, this removes ambiguity for IDs like 0x16, and improves kernel
code greppability (x86 PQ pending).

Finally, the generated CSV and C header files can be quickly checked in
full from the release artifacts at:

  https://gitlab.com/x86-cpuid.org/x86-cpuid-db/-/releases/v2.0

Thanks,

--
Ahmed S. Darwish
Linutronix GmbH