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        <title>ARM Machine Readable Schema - 2.9.6</title>

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            <div class="col-md-6 pull-left"><h1>AARCHMRS Schema <small>2.9.6</small></h1></div>

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    <h1 id="27">2.7</h1>
<h2 id="highlights">Highlights</h2>
<p>Version 2.7.5 introduces additive changes to the schema only. These updates extend the existing schema with new fields and definitions and do not modify or remove any existing schema elements.</p>
<h3 id="aarchmrs-5217-fieldgettersetter-to-be-able-to-represent-shorthand-accessors-275">AARCHMRS-5217: FieldGetterSetter to be able to represent shorthand accessors (2.7.5)</h3>
<p>The <code><a class="schema_link" href="../Accessors/Permission/AccessTypes/Field/ReadWriteAccess_schema.html" title="Accessors.Permission.AccessTypes.Field.ReadWriteAccess">Accessors.Permission.AccessTypes.Field.ReadWriteAccess</a></code> model now supports optional <code>getter</code>
and <code>setter</code> fields storing explicit ASL logic strings.</p>
<h3 id="aarchmrs-5447-improve-the-registers-schema-274">AARCHMRS-5447: Improve the Registers schema (2.7.4)</h3>
<p>The <code><a class="schema_link" href="../Registers_schema.html" title="Registers">Registers</a></code> schema has been improved to include information about the schema.</p>
<h3 id="aarchmrs-5366-disallow-additional-properties-for-conditionalfieldfields-and-resets-273">AARCHMRS-5366: Disallow additional properties for ConditionalField.fields and Resets (2.7.3)</h3>
<p>The schema has been improved to use the correct <code>additionalProperties</code> for the following schemas:</p>
<ul>
<li><code><a class="schema_link" href="../Fields/ConditionalField_schema.html" title="Fields.ConditionalField">Fields.ConditionalField</a></code>: <code>additionalProperties</code> have been disallowed for items in "fields"</li>
<li><code><a class="schema_link" href="../Resets/ArchitecturallyUnknown_schema.html" title="Resets.ArchitecturallyUnknown">Resets.ArchitecturallyUnknown</a></code>: <code>additionalProperties</code> have been  disallowed for the model</li>
<li><code><a class="schema_link" href="../Resets/ConditionalReset_schema.html" title="Resets.ConditionalReset">Resets.ConditionalReset</a></code>: <code>additionalProperties</code> have been disallowed for the model and for items in "resets"</li>
<li><code><a class="schema_link" href="../Resets/InstanceReset_schema.html" title="Resets.InstanceReset">Resets.InstanceReset</a></code>: <code>additionalProperties</code> have been  disallowed for the model</li>
<li><code><a class="schema_link" href="../Resets/Unknown_schema.html" title="Resets.Unknown">Resets.Unknown</a></code>: <code>additionalProperties</code> have been  disallowed for the model</li>
</ul>
<h3 id="aarchmrs-5420-add-registers-schema-to-support-an-array-of-register-registerarray-or-registerblock-273">AARCHMRS-5420: Add Registers schema to support an array of Register, RegisterArray, or RegisterBlock (2.7.3)</h3>
<p>A <a class="schema_link" href="../Registers_schema.html" title="Registers">Registers</a> schema has been added to represent an array that can contain the following objects:</p>
<ul>
<li><code><a class="schema_link" href="../Register_schema.html" title="Register">Register</a></code></li>
<li><code><a class="schema_link" href="../RegisterArray_schema.html" title="RegisterArray">RegisterArray</a></code></li>
<li><code><a class="schema_link" href="../RegisterBlock_schema.html" title="RegisterBlock">RegisterBlock</a></code></li>
</ul>
<h3 id="aarchmrs-5239-support-for-additional-combinations-of-readwrite-accesses-and-side-effects">AARCHMRS-5239: Support for additional combinations of read/write accesses and side effects</h3>
<p>Support has been added for the following shorthand read/write accesses:</p>
<ol>
<li><strong>RC/WS</strong> (W: sets all bits, R: clears all bits)</li>
<li><strong>RS/WC</strong> (W: clears all bits, R: sets all bits)</li>
<li><strong>RC/W1S</strong> (W: 1/0 sets/no effect on matching bit, R: clears all bits)</li>
<li><strong>RS/W1C</strong> (W: 1/0 clears/no effect on matching bit, R: sets all bits)</li>
<li><strong>RC/W0S</strong> (W: 1/0 no effect on/sets matching bit, R: clears all bits)</li>
<li><strong>RS/W0C</strong> (W: 1/0 no effect on/clears matching bit, R: sets all bits)</li>
<li><strong>ERROR/W</strong> (W: as-is, R: error)</li>
<li><strong>ERROR/W0C</strong> (W: clears all bits, R: error)</li>
<li><strong>ERROR/W0S</strong> (W: sets all bits, R: error)</li>
</ol>
<h3 id="aarchmrs-5227-update-asl1-implication-and-logical-equivalence-syntax">AARCHMRS-5227: Update ASL1 implication and logical equivalence syntax</h3>
<p>The syntax of the implication and logical equivalence has been updated in the BinaryOp schema
to align with the latest ASL reference documentation as the following:</p>
<ul>
<li>Implication: --&gt; becomes ==&gt;</li>
<li>Biconditional: &lt;-&gt; becomes &lt;=&gt;</li>
</ul>
<p>For more details refer to Chapter 3 of <a href="https://developer.arm.com/documentation/ddi0626/00bet0/?lang=en">ASLRef BET0</a>.</p>
<h3 id="aarchmrs-5226-change-astconcat-into-an-astbinaryop-operator">AARCHMRS-5226: Change AST.Concat into an AST.BinaryOp operator (<code>::</code>)</h3>
<p>In order to align more closely with the ASL Reference manual we have updated bit concatenation
to an AST.BinaryOp operator.</p>
<p>AST.Concat will remain in use when specifying mulit-bit field accesses of the form <code>REG.[F1,F2]</code> and is
planned for deprecation in a future version when a better model is made available.</p>
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