1 <?xml version="1.0" encoding="utf-8"?>

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     7     Nokia Corporation - initial contribution.

     8 Contributors: 

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    10 <!DOCTYPE concept

    11   PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">

    12 <concept id="GUID-96F07979-3863-5198-AF8B-4ACC1193CF3E" xml:lang="en"><title>Level

    13 2 Cache Tutorial</title><shortdesc>This topic describes how to configure the base port to use the

    14 ARM L210 cache or L220 cache controllers in ARM processors. </shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

    15 <p>Cache is a fast buffer that keeps copies of recently accessed memory. </p>

    16 <section id="GUID-6ECBAFBD-87A5-4CB2-8A83-24F5208A58DA"><title>L210 Cache</title> <p>In the <filepath>variant.mmh</filepath> file,

    17 set the macro: </p> <codeblock id="GUID-FB4E4E84-828F-5FD6-A296-F55FA8F7C25D" xml:space="preserve">__ARM_L210_CACHE__</codeblock> <p>You

    18 must also set a L210 Cache macro and initialise Level 2 cache in the Bootstrap.

    19 See <xref href="GUID-4A910E9F-E881-51D7-A84A-CBC6AC343FD1.dita">Level 2 Cache Macros</xref> and <xref href="GUID-F67FA7B5-F6D1-5C5C-8E10-A8E317A778E4.dita#GUID-F67FA7B5-F6D1-5C5C-8E10-A8E317A778E4/GUID-C111DA06-F7EE-5E70-8D86-26BA2213B506">HardwareInitialise()</xref>. </p> <p>The

    20 L210 cache is switched on by generic Symbian OS code before jumping into the

    21 kernel code. The cache is switched on after the MMU and L1 cache are enabled. </p> </section>

    22 <section id="GUID-D713DF71-C896-45EA-86D6-55E5FF9CFABC"><title>L220 Cache</title> <p>In the <filepath>variant.mmh</filepath> file,

    23 set the macro: </p> <codeblock id="GUID-8DCEE6B7-E852-5B3D-AFE7-E512DCAA73C0" xml:space="preserve">__ARM_L220_CACHE__</codeblock> <p>You

    24 must also set a L220 Cache macro and initialise Level 2 cache in the Bootstrap.

    25 See <xref href="GUID-4A910E9F-E881-51D7-A84A-CBC6AC343FD1.dita">Level 2 Cache Macros</xref> and <xref href="GUID-F67FA7B5-F6D1-5C5C-8E10-A8E317A778E4.dita#GUID-F67FA7B5-F6D1-5C5C-8E10-A8E317A778E4/GUID-C111DA06-F7EE-5E70-8D86-26BA2213B506">HardwareInitialise()</xref>. </p> <p>Code

    26 to switch on the L220 cache on must be provided by the base port. You can

    27 do this in the <xref href="GUID-F67FA7B5-F6D1-5C5C-8E10-A8E317A778E4.dita#GUID-F67FA7B5-F6D1-5C5C-8E10-A8E317A778E4/GUID-C111DA06-F7EE-5E70-8D86-26BA2213B506">HardwareInitialise()</xref> function

    28 or the <xref href="GUID-B3F6FC45-3BF0-5F92-8325-44C705BA47AE.dita#GUID-B3F6FC45-3BF0-5F92-8325-44C705BA47AE/GUID-EEF889E7-915F-57E9-8E2D-DC17B24C7728">BTF_Final()</xref> function

    29 in the Bootstrap. </p> </section>

    30 </conbody></concept>