1<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>intel_logical_ring_begin</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="Linux GPU Driver Developer's Guide"><link rel="up" href="ch04s03.html#id-1.4.3.5.5" title="Logical Rings, Logical Ring Contexts and Execlists"><link rel="prev" href="API-intel-lrc-irq-handler.html" title="intel_lrc_irq_handler"><link rel="next" href="API-intel-execlists-submission.html" title="intel_execlists_submission"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span class="phrase">intel_logical_ring_begin</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-intel-lrc-irq-handler.html">Prev</a> </td><th width="60%" align="center">Logical Rings, Logical Ring Contexts and Execlists</th><td width="20%" align="right"> <a accesskey="n" href="API-intel-execlists-submission.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-intel-logical-ring-begin"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>intel_logical_ring_begin — 
2     prepare the logical ringbuffer to accept some commands
3 </p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">intel_logical_ring_begin </b>(</code></td><td>struct drm_i915_gem_request * <var class="pdparam">req</var>, </td></tr><tr><td> </td><td>int <var class="pdparam">num_dwords</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a name="id-1.4.3.5.5.25.5"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>req</code></em></span></dt><dd><p>
4     The request to start some new work for
5    </p></dd><dt><span class="term"><em class="parameter"><code>num_dwords</code></em></span></dt><dd><p>
6     number of DWORDs that we plan to write to the ringbuffer.
7    </p></dd></dl></div></div><div class="refsect1"><a name="id-1.4.3.5.5.25.6"></a><h2>Description</h2><p>
8   The ringbuffer might not be ready to accept the commands right away (maybe it needs to
9   be wrapped, or wait a bit for the tail to be updated). This function takes care of that
10   and also preallocates a request (every workload submission is still mediated through
11   requests, same as it did with legacy ringbuffer submission).
12</p></div><div class="refsect1"><a name="id-1.4.3.5.5.25.7"></a><h2>Return</h2><p>
13   non-zero if the ringbuffer is not ready to be written to.
14</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="API-intel-lrc-irq-handler.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="ch04s03.html#id-1.4.3.5.5">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="API-intel-execlists-submission.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top"><span class="phrase">intel_lrc_irq_handler</span> </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> <span class="phrase">intel_execlists_submission</span></td></tr></table></div></body></html>
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