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| <section id="network-drivers"> |
| <span id="netdriver"></span><h1>Network Drivers<a class="headerlink" href="#network-drivers" title="Permalink to this heading"></a></h1> |
| <p>The NuttX network driver is split into two parts:</p> |
| <ol class="arabic simple"> |
| <li><p>An “upper half”, generic driver that provides the common network |
| interface to application level code, and</p></li> |
| <li><p>A “lower half”, platform-specific driver that implements the |
| low-level timer controls to implement the network functionality.</p></li> |
| </ol> |
| <p>Files supporting network driver can be found in the following locations:</p> |
| <ul class="simple"> |
| <li><p><strong>Interface Definition</strong>. The header file for the NuttX network |
| driver resides at <code class="docutils literal notranslate"><span class="pre">include/nuttx/net/netdev_lowerhalf.h</span></code>. This |
| header file includes the interface between the “upper half” and |
| “lower half” drivers.</p></li> |
| <li><p><strong>“Upper Half” Driver</strong>. The generic, “upper half” network driver |
| resides at <code class="docutils literal notranslate"><span class="pre">drivers/net/netdev_upperhalf.c</span></code>.</p></li> |
| <li><p><strong>“Lower Half” Drivers</strong>. Platform-specific network drivers reside |
| in <code class="docutils literal notranslate"><span class="pre">arch/<architecture>/src/<hardware></span></code> or <code class="docutils literal notranslate"><span class="pre">drivers/net</span></code> |
| directory for the specific processor <code class="docutils literal notranslate"><span class="pre"><architecture></span></code> and for |
| the specific <code class="docutils literal notranslate"><span class="pre"><chip></span></code> network peripheral devices.</p></li> |
| </ul> |
| <p><strong>Special Note</strong>: Not all network drivers are implemented with this |
| architecture. Known lower-half drivers: |
| <code class="docutils literal notranslate"><span class="pre">arch/sim/src/sim/sim_netdriver.c</span></code>, <code class="docutils literal notranslate"><span class="pre">drivers/virtio/virtio-net.c</span></code></p> |
| <section id="how-to-change-full-network-driver-into-lower-half-one"> |
| <h2>How to change full network driver into lower-half one<a class="headerlink" href="#how-to-change-full-network-driver-into-lower-half-one" title="Permalink to this heading"></a></h2> |
| <p>We have many network drivers that are implemented as full network drivers |
| with <code class="docutils literal notranslate"><span class="pre">include/nuttx/net/netdev.h</span></code>, we can change them into lower-half |
| drivers to remove the common code (which is already in upper-half driver). |
| Here is a guide to do so:</p> |
| <ol class="arabic simple"> |
| <li><p>Change <code class="docutils literal notranslate"><span class="pre">struct</span> <span class="pre">net_driver_s</span></code> to <code class="docutils literal notranslate"><span class="pre">struct</span> <span class="pre">netdev_lowerhalf_s</span></code> in |
| the network driver structure. If you really need to touch some fields |
| inside <code class="docutils literal notranslate"><span class="pre">struct</span> <span class="pre">net_driver_s</span></code> like MAC address, you can access them |
| through <code class="docutils literal notranslate"><span class="pre">struct</span> <span class="pre">netdev_lowerhalf_s::netdev</span></code>.</p></li> |
| <li><p>Change the function names called in the network driver file to the names |
| with prefix <code class="docutils literal notranslate"><span class="pre">netdev_lower_</span></code>, e.g. <code class="docutils literal notranslate"><span class="pre">netdev_lower_register</span></code> and |
| <code class="docutils literal notranslate"><span class="pre">netdev_lower_carrier_on</span></code>.</p></li> |
| <li><p>Change the core functions called by work queue like <code class="docutils literal notranslate"><span class="pre">txpoll</span></code> as |
| <code class="docutils literal notranslate"><span class="pre">transmit</span></code> and <code class="docutils literal notranslate"><span class="pre">receive</span></code> in the <code class="docutils literal notranslate"><span class="pre">netdev_ops_s</span></code> structure. You may |
| need to change <code class="docutils literal notranslate"><span class="pre">memcpy</span></code> for <code class="docutils literal notranslate"><span class="pre">d_buf</span></code> into <code class="docutils literal notranslate"><span class="pre">netpkt_copyin</span></code> and |
| <code class="docutils literal notranslate"><span class="pre">netpkt_copyout</span></code>.</p> |
| <ul class="simple"> |
| <li><p>Note that the <code class="docutils literal notranslate"><span class="pre">receive</span></code> function just need to return the received |
| packet instead of calling functions like <code class="docutils literal notranslate"><span class="pre">ipv4_input</span></code> or doing reply. |
| The upper-half will call <code class="docutils literal notranslate"><span class="pre">receive</span></code> to get all packets until it |
| returns <code class="docutils literal notranslate"><span class="pre">NULL</span></code> and send these packets into the network stack.</p></li> |
| <li><p>Also remember to call <code class="docutils literal notranslate"><span class="pre">netpkt_free</span></code> for the transmitted packets.</p></li> |
| </ul> |
| </li> |
| <li><p>Remove work queues related to send and receive, and replace them |
| with calling <code class="docutils literal notranslate"><span class="pre">netdev_lower_txdone</span></code> and <code class="docutils literal notranslate"><span class="pre">netdev_lower_rxready</span></code>. |
| Then the upper-half driver will call <code class="docutils literal notranslate"><span class="pre">transmit</span></code> and <code class="docutils literal notranslate"><span class="pre">receive</span></code> to |
| send/get packets.</p></li> |
| <li><p>Remove any buffer related to <code class="docutils literal notranslate"><span class="pre">d_buf</span></code>, and make sure <code class="docutils literal notranslate"><span class="pre">d_buf</span></code> is not |
| used in the lower-half driver.</p></li> |
| <li><p>Remove <code class="docutils literal notranslate"><span class="pre">txavail</span></code> function, the upper-half driver will call <code class="docutils literal notranslate"><span class="pre">transmit</span></code> |
| when it has packets to send.</p></li> |
| <li><p>Remove the statistics macros like <code class="docutils literal notranslate"><span class="pre">NETDEV_TXPACKETS</span></code>, <code class="docutils literal notranslate"><span class="pre">NETDEV_TXDONE</span></code>, |
| <code class="docutils literal notranslate"><span class="pre">NETDEV_RXPACKETS</span></code> or <code class="docutils literal notranslate"><span class="pre">NETDEV_RXDROPPED</span></code>, these macros are well |
| handled in upper-half. But you may still keep macros like |
| <code class="docutils literal notranslate"><span class="pre">NETDEV_TXTIMEOUTS</span></code> and <code class="docutils literal notranslate"><span class="pre">NETDEV_RXERRORS</span></code> because the upper-half |
| cannot know whether these error happens.</p></li> |
| <li><p>Find a suitable <code class="docutils literal notranslate"><span class="pre">quota</span></code> for the driver, and set it in the driver |
| initialization function. The quota is the maximum number of buffers |
| that the driver can hold at the same time. For example, if the TX quota |
| is set to 5, it means that if the driver has 5 unreleased packets |
| (<code class="docutils literal notranslate"><span class="pre">netpkt_free</span></code>), the upper-half will not call <code class="docutils literal notranslate"><span class="pre">transmit</span></code> until they |
| are released.</p> |
| <ul class="simple"> |
| <li><p>Note: An exception is that if the net stack is replying for RX packet, |
| this replied packet will always be put into <code class="docutils literal notranslate"><span class="pre">transmit</span></code>, which may |
| exceed the TX quota temporarily.</p></li> |
| </ul> |
| </li> |
| </ol> |
| </section> |
| <section id="lower-half-example"> |
| <h2>“Lower Half” Example<a class="headerlink" href="#lower-half-example" title="Permalink to this heading"></a></h2> |
| <div class="highlight-c notranslate"><div class="highlight"><pre><span></span><span class="k">struct</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_priv_s</span> |
| <span class="p">{</span> |
| <span class="w"> </span><span class="cm">/* This holds the information visible to the NuttX network */</span> |
| |
| <span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="nc">netdev_lowerhalf_s</span><span class="w"> </span><span class="n">dev</span><span class="p">;</span> |
| |
| <span class="w"> </span><span class="p">...</span> |
| <span class="p">};</span> |
| |
| <span class="k">static</span><span class="w"> </span><span class="k">const</span><span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="nc">netdev_ops_s</span><span class="w"> </span><span class="n">g_ops</span><span class="w"> </span><span class="o">=</span> |
| <span class="p">{</span> |
| <span class="w"> </span><span class="p">.</span><span class="n">ifup</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_ifup</span><span class="p">,</span> |
| <span class="w"> </span><span class="p">.</span><span class="n">ifdown</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_ifdown</span><span class="p">,</span> |
| <span class="w"> </span><span class="p">.</span><span class="n">transmit</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_transmit</span><span class="p">,</span> |
| <span class="w"> </span><span class="p">.</span><span class="n">receive</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_receive</span><span class="p">,</span> |
| <span class="w"> </span><span class="p">.</span><span class="n">addmac</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_addmac</span><span class="p">,</span> |
| <span class="w"> </span><span class="p">.</span><span class="n">rmmac</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_rmmac</span><span class="p">,</span> |
| <span class="w"> </span><span class="p">.</span><span class="n">ioctl</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_ioctl</span> |
| <span class="p">};</span> |
| |
| <span class="cm">/* The Wi-Fi driver registration function can be implemented as follows,</span> |
| <span class="cm"> * where <chip> refers to the chip name. netdev_lower_register() is the</span> |
| <span class="cm"> * network device interface provided by upper-half drivers to register</span> |
| <span class="cm"> * network device drivers.</span> |
| <span class="cm"> */</span> |
| |
| <span class="kt">int</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_netdev_init</span><span class="p">(</span><span class="n">FAR</span><span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_priv_s</span><span class="w"> </span><span class="o">*</span><span class="n">priv</span><span class="p">)</span> |
| <span class="p">{</span> |
| <span class="w"> </span><span class="n">FAR</span><span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="nc">netdev_lowerhalf_s</span><span class="w"> </span><span class="o">*</span><span class="n">dev</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="o">&</span><span class="n">priv</span><span class="o">-></span><span class="n">dev</span><span class="p">;</span> |
| |
| <span class="w"> </span><span class="n">dev</span><span class="o">-></span><span class="n">ops</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="o">&</span><span class="n">g_ops</span><span class="p">;</span> |
| |
| <span class="w"> </span><span class="cm">/* The maximum number of buffers that the driver can hold</span> |
| <span class="cm"> * at the same time. For example, if the TX quota is set to 5, it</span> |
| <span class="cm"> * means that if the driver has 5 unreleased packets (netpkt_free),</span> |
| <span class="cm"> * the upper layer will not call transmit until they are released.</span> |
| <span class="cm"> * After the rx quota is used up and no new buffer can be allocated</span> |
| <span class="cm"> * (netpkt_alloc), it needs to notify the upper layer</span> |
| <span class="cm"> * (netdev_lower_rxready) and restore the quota by submitting buffer</span> |
| <span class="cm"> * back through receive function.</span> |
| <span class="cm"> * If the driver processes each packet individually (without</span> |
| <span class="cm"> * accumulating multiple packets before sending/receiving), it can be</span> |
| <span class="cm"> * set to 1.</span> |
| <span class="cm"> */</span> |
| |
| <span class="w"> </span><span class="n">dev</span><span class="o">-></span><span class="n">quota</span><span class="p">[</span><span class="n">NETPKT_TX</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">1</span><span class="p">;</span> |
| <span class="w"> </span><span class="n">dev</span><span class="o">-></span><span class="n">quota</span><span class="p">[</span><span class="n">NETPKT_RX</span><span class="p">]</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="mi">1</span><span class="p">;</span> |
| |
| <span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="n">netdev_lower_register</span><span class="p">(</span><span class="n">dev</span><span class="p">,</span><span class="w"> </span><span class="n">NET_LL_ETHERNET</span><span class="p">);</span> |
| <span class="p">}</span> |
| |
| <span class="cm">/* The transmit function can be implemented as follows, where <chip></span> |
| <span class="cm"> * refers to the chip name.</span> |
| <span class="cm"> */</span> |
| |
| <span class="k">static</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_transmit</span><span class="p">(</span><span class="n">FAR</span><span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="nc">netdev_lowerhalf_s</span><span class="w"> </span><span class="o">*</span><span class="n">dev</span><span class="p">,</span> |
| <span class="w"> </span><span class="n">FAR</span><span class="w"> </span><span class="n">netpkt_t</span><span class="w"> </span><span class="o">*</span><span class="n">pkt</span><span class="p">)</span> |
| <span class="p">{</span> |
| <span class="w"> </span><span class="n">FAR</span><span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_priv_s</span><span class="w"> </span><span class="o">*</span><span class="n">priv</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="p">(</span><span class="n">FAR</span><span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_priv_s</span><span class="w"> </span><span class="o">*</span><span class="p">)</span><span class="n">dev</span><span class="p">;</span> |
| <span class="w"> </span><span class="kt">unsigned</span><span class="w"> </span><span class="kt">int</span><span class="w"> </span><span class="n">len</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">netpkt_getdatalen</span><span class="p">(</span><span class="n">dev</span><span class="p">,</span><span class="w"> </span><span class="n">pkt</span><span class="p">);</span> |
| |
| <span class="cp">#if you want to do offloading</span> |
| <span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="o">!</span><span class="n">netpkt_is_fragmented</span><span class="p">(</span><span class="n">pkt</span><span class="p">))</span> |
| <span class="w"> </span><span class="p">{</span> |
| <span class="w"> </span><span class="cm">/* Contiguous memory, just use data pointer */</span> |
| |
| <span class="w"> </span><span class="n">FAR</span><span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="o">*</span><span class="n">databuf</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">netpkt_getdata</span><span class="p">(</span><span class="n">dev</span><span class="p">,</span><span class="w"> </span><span class="n">pkt</span><span class="p">);</span> |
| <span class="w"> </span><span class="n">FAR</span><span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="o">*</span><span class="n">devbuf</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">databuf</span><span class="w"> </span><span class="o">-</span><span class="w"> </span><span class="k">sizeof</span><span class="p">(</span><span class="k">struct</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_txhead_s</span><span class="p">);</span> |
| |
| <span class="w"> </span><span class="cm">/* Do Transmit. Note: `databuf` points to the L2 data, and there is</span> |
| <span class="cm"> * a reserved memory with size of `CONFIG_NET_LL_GUARDSIZE` before</span> |
| <span class="cm"> * databuf to be used for driver header, drivers can just fill data</span> |
| <span class="cm"> * there (`devbuf`) and start the transmission.</span> |
| <span class="cm"> */</span> |
| |
| <span class="w"> </span><span class="p">...</span> |
| <span class="w"> </span><span class="p">}</span> |
| <span class="w"> </span><span class="k">else</span> |
| <span class="cp">#endif</span> |
| <span class="w"> </span><span class="p">{</span> |
| <span class="w"> </span><span class="cm">/* Copyout the L2 data and transmit. */</span> |
| |
| <span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">devbuf</span><span class="p">[</span><span class="mi">1600</span><span class="p">];</span> |
| <span class="w"> </span><span class="n">netpkt_copyout</span><span class="p">(</span><span class="n">dev</span><span class="p">,</span><span class="w"> </span><span class="n">devbuf</span><span class="p">,</span><span class="w"> </span><span class="n">pkt</span><span class="p">,</span><span class="w"> </span><span class="n">len</span><span class="p">,</span><span class="w"> </span><span class="mi">0</span><span class="p">);</span> |
| |
| <span class="w"> </span><span class="cm">/* Do Transmit */</span> |
| |
| <span class="w"> </span><span class="p">...</span> |
| <span class="w"> </span><span class="p">}</span> |
| |
| <span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="n">OK</span><span class="p">;</span> |
| <span class="p">}</span> |
| |
| <span class="k">static</span><span class="w"> </span><span class="kt">void</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_txdone_interrupt</span><span class="p">(</span><span class="n">FAR</span><span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_priv_s</span><span class="w"> </span><span class="o">*</span><span class="n">priv</span><span class="p">)</span> |
| <span class="p">{</span> |
| <span class="w"> </span><span class="n">FAR</span><span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="nc">netdev_lowerhalf_s</span><span class="w"> </span><span class="o">*</span><span class="n">dev</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="o">&</span><span class="n">priv</span><span class="o">-></span><span class="n">dev</span><span class="p">;</span> |
| |
| <span class="w"> </span><span class="cm">/* Perform some processing in the driver (if necessary) */</span> |
| |
| <span class="w"> </span><span class="p">...</span> |
| |
| <span class="w"> </span><span class="cm">/* Free the buffer and notify the upper layer */</span> |
| |
| <span class="w"> </span><span class="n">netpkt_free</span><span class="p">(</span><span class="n">dev</span><span class="p">,</span><span class="w"> </span><span class="n">pkt</span><span class="p">,</span><span class="w"> </span><span class="n">NETPKT_TX</span><span class="p">);</span> |
| <span class="w"> </span><span class="n">netdev_lower_txdone</span><span class="p">(</span><span class="n">dev</span><span class="p">);</span> |
| <span class="p">}</span> |
| |
| <span class="cm">/* The receive function can be implemented as follows, where <chip></span> |
| <span class="cm"> * refers to the chip name.</span> |
| <span class="cm"> */</span> |
| |
| <span class="k">static</span><span class="w"> </span><span class="kt">void</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_rxready_interrupt</span><span class="p">(</span><span class="n">FAR</span><span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_priv_s</span><span class="w"> </span><span class="o">*</span><span class="n">priv</span><span class="p">)</span> |
| <span class="p">{</span> |
| <span class="w"> </span><span class="n">FAR</span><span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="nc">netdev_lowerhalf_s</span><span class="w"> </span><span class="o">*</span><span class="n">dev</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="o">&</span><span class="n">priv</span><span class="o">-></span><span class="n">dev</span><span class="p">;</span> |
| <span class="w"> </span><span class="n">netdev_lower_rxready</span><span class="p">(</span><span class="n">dev</span><span class="p">);</span> |
| <span class="p">}</span> |
| |
| <span class="k">static</span><span class="w"> </span><span class="n">FAR</span><span class="w"> </span><span class="n">netpkt_t</span><span class="w"> </span><span class="o">*<</span><span class="n">chip</span><span class="o">></span><span class="n">_receive</span><span class="p">(</span><span class="n">FAR</span><span class="w"> </span><span class="k">struct</span><span class="w"> </span><span class="nc">netdev_lowerhalf_s</span><span class="w"> </span><span class="o">*</span><span class="n">dev</span><span class="p">)</span> |
| <span class="p">{</span> |
| <span class="w"> </span><span class="cm">/* It is also possible to allocate the pkt and receive the data in</span> |
| <span class="cm"> * advance, and then call rxready and return pkt through receive</span> |
| <span class="cm"> */</span> |
| |
| <span class="w"> </span><span class="n">FAR</span><span class="w"> </span><span class="n">netpkt_t</span><span class="w"> </span><span class="o">*</span><span class="n">pkt</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">netpkt_alloc</span><span class="p">(</span><span class="n">dev</span><span class="p">,</span><span class="w"> </span><span class="n">NETPKT_RX</span><span class="p">);</span> |
| |
| <span class="w"> </span><span class="k">if</span><span class="w"> </span><span class="p">(</span><span class="n">pkt</span><span class="p">)</span> |
| <span class="w"> </span><span class="p">{</span> |
| <span class="cp">#if NETPKT_BUFLEN > 15xx && you want to do offloading</span> |
| <span class="w"> </span><span class="cm">/* Write directly to the buffer inside pkt, len corresponds to the</span> |
| <span class="cm"> * length of L2 data (need the NETPKT_BUFLEN to be large enough to</span> |
| <span class="cm"> * hold the data). The `<chip>_rxhead_s` is the driver header before</span> |
| <span class="cm"> * the actual data (maybe you don't have).</span> |
| <span class="cm"> */</span> |
| |
| <span class="w"> </span><span class="n">len</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">receive_data_into</span><span class="p">(</span><span class="n">netpkt_getbase</span><span class="p">(</span><span class="n">pkt</span><span class="p">));</span> |
| <span class="w"> </span><span class="n">netpkt_resetreserved</span><span class="p">(</span><span class="o">&</span><span class="n">priv</span><span class="o">-></span><span class="n">dev</span><span class="p">,</span><span class="w"> </span><span class="n">pkt</span><span class="p">,</span><span class="w"> </span><span class="k">sizeof</span><span class="p">(</span><span class="k">struct</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_rxhead_s</span><span class="p">));</span> |
| <span class="w"> </span><span class="n">netpkt_setdatalen</span><span class="p">(</span><span class="o">&</span><span class="n">priv</span><span class="o">-></span><span class="n">dev</span><span class="p">,</span><span class="w"> </span><span class="n">pkt</span><span class="p">,</span><span class="w"> </span><span class="n">len</span><span class="p">);</span> |
| <span class="cp">#else</span> |
| <span class="w"> </span><span class="kt">uint8_t</span><span class="w"> </span><span class="n">devbuf</span><span class="p">[</span><span class="mi">1600</span><span class="p">];</span> |
| |
| <span class="w"> </span><span class="cm">/* Copy from src, len corresponds to the length of L2 data, you can</span> |
| <span class="cm"> * always use this method to receive data. The `<chip>_rxhead_s` is</span> |
| <span class="cm"> * the driver header before the actual data (maybe you don't have).</span> |
| <span class="cm"> */</span> |
| |
| <span class="w"> </span><span class="n">len</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">receive_data_into</span><span class="p">(</span><span class="n">devbuf</span><span class="p">);</span> |
| <span class="w"> </span><span class="n">netpkt_copyin</span><span class="p">(</span><span class="n">dev</span><span class="p">,</span><span class="w"> </span><span class="n">pkt</span><span class="p">,</span><span class="w"> </span><span class="n">devbuf</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="k">sizeof</span><span class="p">(</span><span class="k">struct</span><span class="w"> </span><span class="o"><</span><span class="n">chip</span><span class="o">></span><span class="n">_rxhead_s</span><span class="p">),</span><span class="w"> </span><span class="n">len</span><span class="p">,</span><span class="w"> </span><span class="mi">0</span><span class="p">);</span> |
| <span class="cp">#endif</span> |
| <span class="w"> </span><span class="p">}</span> |
| |
| <span class="w"> </span><span class="k">return</span><span class="w"> </span><span class="n">pkt</span><span class="p">;</span> |
| <span class="p">}</span> |
| </pre></div> |
| </div> |
| </section> |
| </section> |
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