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<?xml-stylesheet type="text/xsl" href="https://community.arm.com/utility/feedstylesheets/rss.xsl" media="screen"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/" xmlns:wfw="http://wellformedweb.org/CommentAPI/"><channel><title>Is it possible to move up from EL0 AARCH32 to EL1 AARCH64</title><link>https://community.arm.com/developer/ip-products/processors/f/cortex-a-forum/47708/is-it-possible-to-move-up-from-el0-aarch32-to-el1-aarch64</link><description> In baremetal boot code implementation https://developer.arm.com/documentation/dai0527/a , it is explained that depending on the SOC implementation, if the ARMv8 comes out on reset as EL3, AArch64 configuration, then it is possible to drop down to EL0</description><dc:language>en-US</dc:language><generator>Telligent Community 10</generator><item><title>RE: Is it possible to move up from EL0 AARCH32 to EL1 AARCH64</title><link>https://community.arm.com/thread/167667?ContentTypeID=1</link><pubDate>Thu, 24 Sep 2020 15:06:49 GMT</pubDate><guid isPermaLink="false">dd9e70c8-6d3c-4c71-b136-2456382a7b5c:1df8915d-98c8-4f69-a07b-05e8ffc671bb</guid><dc:creator>vstehle</dc:creator><description>&lt;p&gt;Hi &lt;a href="/members/harshit" class="internal-link view-user-profile"&gt;Harshit&lt;/a&gt;,&lt;/p&gt;
&lt;p&gt;Your bootable application could go back to EL1/EL2 at the end of its execution.&lt;/p&gt;
&lt;p&gt;Going from 32b EL0 to EL1 is typically done with an&amp;nbsp;&lt;a href="https://developer.arm.com/documentation/den0013/d/instruction-summary/instruction-summary/svc?search=5eec6e55e24a5e02d07b256e"&gt;AArch32 SVC&lt;/a&gt;&amp;nbsp;instruction.&lt;/p&gt;
&lt;p&gt;64b EL1 can call EL2 with an AArch64 HVC instruction.&lt;/p&gt;
&lt;p&gt;64b EL1/EL2 can call EL3 with an AArch64 SMC&amp;nbsp;instruction.&lt;/p&gt;
&lt;p&gt;(See&amp;nbsp;&lt;a href="https://developer.arm.com/documentation/den0024/a/aarch64-exception-handling?lang=en"&gt;AArch64 Exceptions&lt;/a&gt;.)&lt;/p&gt;
&lt;p&gt;Your EL3 bootloader will need to install the proper exception handlers in EL3/EL2/EL1 before running the bootable application.&lt;/p&gt;&lt;div style="clear:both;"&gt;&lt;/div&gt;</description></item></channel></rss>