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-rw-r--r--documentation/kernel-dev/kernel-dev-common.xml301
1 files changed, 147 insertions, 154 deletions
diff --git a/documentation/kernel-dev/kernel-dev-common.xml b/documentation/kernel-dev/kernel-dev-common.xml
index 0f5e09cd47..28bedd1785 100644
--- a/documentation/kernel-dev/kernel-dev-common.xml
+++ b/documentation/kernel-dev/kernel-dev-common.xml
@@ -70,7 +70,7 @@
70 <listitem><para> 70 <listitem><para>
71 <emphasis>Initialize the BitBake Environment:</emphasis> 71 <emphasis>Initialize the BitBake Environment:</emphasis>
72 Before building an extensible SDK, you need to 72 Before building an extensible SDK, you need to
73 initialize the BitBake build environment by sourcing a 73 initialize the BitBake build environment by sourcing the
74 build environment script 74 build environment script
75 (i.e. <ulink url='&YOCTO_DOCS_REF_URL;#structure-core-script'><filename>oe-init-build-env</filename></ulink>): 75 (i.e. <ulink url='&YOCTO_DOCS_REF_URL;#structure-core-script'><filename>oe-init-build-env</filename></ulink>):
76 <literallayout class='monospaced'> 76 <literallayout class='monospaced'>
@@ -155,8 +155,8 @@
155 </para></listitem> 155 </para></listitem>
156 <listitem><para> 156 <listitem><para>
157 <emphasis>Build the Extensible SDK:</emphasis> 157 <emphasis>Build the Extensible SDK:</emphasis>
158 Use BitBake to build the extensible SDK specifically for 158 Use BitBake to build the extensible SDK specifically
159 the Minnowboard: 159 for use with images to be run using QEMU:
160 <literallayout class='monospaced'> 160 <literallayout class='monospaced'>
161 $ cd ~/poky/build 161 $ cd ~/poky/build
162 $ bitbake core-image-minimal -c populate_sdk_ext 162 $ bitbake core-image-minimal -c populate_sdk_ext
@@ -280,7 +280,7 @@
280 <listitem><para> 280 <listitem><para>
281 <emphasis>Initialize the BitBake Environment:</emphasis> 281 <emphasis>Initialize the BitBake Environment:</emphasis>
282 Before you can do anything using BitBake, you need to 282 Before you can do anything using BitBake, you need to
283 initialize the BitBake build environment by sourcing a 283 initialize the BitBake build environment by sourcing the
284 build environment script 284 build environment script
285 (i.e. <ulink url='&YOCTO_DOCS_REF_URL;#structure-core-script'><filename>oe-init-build-env</filename></ulink>). 285 (i.e. <ulink url='&YOCTO_DOCS_REF_URL;#structure-core-script'><filename>oe-init-build-env</filename></ulink>).
286 Also, for this example, be sure that the local branch 286 Also, for this example, be sure that the local branch
@@ -1009,66 +1009,58 @@
1009 "<link linkend='getting-ready-to-develop-using-devtool'>Getting Ready to Develop using <filename>devtool</filename></link>" 1009 "<link linkend='getting-ready-to-develop-using-devtool'>Getting Ready to Develop using <filename>devtool</filename></link>"
1010 Section. 1010 Section.
1011 </note> 1011 </note>
1012 </para> 1012 <orderedlist>
1013 1013 <listitem><para>
1014 <para> 1014 <emphasis>Check Out the Kernel Source Files:</emphasis>
1015 Also, for more information on patching the kernel, see the 1015 First you must use <filename>devtool</filename> to checkout
1016 "<link linkend='applying-patches'>Applying Patches</link>" 1016 the kernel source code in its workspace.
1017 section. 1017 Be sure you are in the terminal set up to do work
1018 </para> 1018 with the extensible SDK.
1019 1019 <note>
1020 <orderedlist> 1020 See this
1021 <listitem><para> 1021 <link linkend='setting-up-the-esdk-terminal'>step</link>
1022 <emphasis>Check Out the Kernel Source Files:</emphasis> 1022 in the
1023 First you must use <filename>devtool</filename> to checkout 1023 "<link linkend='getting-ready-to-develop-using-devtool'>Getting Ready to Develop Using <filename>devtool</filename></link>"
1024 the kernel source code in its workspace. 1024 section for more information.
1025 Be sure you are in the terminal set up to do work 1025 </note>
1026 with the extensible SDK. 1026 Use the following <filename>devtool</filename> command
1027 <note> 1027 to check out the code:
1028 See this
1029 <link linkend='setting-up-the-esdk-terminal'>step</link>
1030 in the
1031 "<link linkend='getting-ready-to-develop-using-devtool'>Getting Ready to Develop Using <filename>devtool</filename></link>"
1032 section for more information.
1033 </note>
1034 Use the following <filename>devtool</filename> command
1035 to check out the code:
1036 <literallayout class='monospaced'>
1037 $ devtool modify linux-yocto
1038 </literallayout>
1039 <note>
1040 During the checkout operation, a bug exists that could
1041 cause errors such as the following to appear:
1042 <literallayout class='monospaced'> 1028 <literallayout class='monospaced'>
1029 $ devtool modify linux-yocto
1030 </literallayout>
1031 <note>
1032 During the checkout operation, a bug exists that could
1033 cause errors such as the following to appear:
1034 <literallayout class='monospaced'>
1043 ERROR: Taskhash mismatch 2c793438c2d9f8c3681fd5f7bc819efa versus 1035 ERROR: Taskhash mismatch 2c793438c2d9f8c3681fd5f7bc819efa versus
1044 be3a89ce7c47178880ba7bf6293d7404 for 1036 be3a89ce7c47178880ba7bf6293d7404 for
1045 /path/to/esdk/layers/poky/meta/recipes-kernel/linux/linux-yocto_4.10.bb.do_unpack 1037 /path/to/esdk/layers/poky/meta/recipes-kernel/linux/linux-yocto_4.10.bb.do_unpack
1046 </literallayout>
1047 You can safely ignore these messages.
1048 The source code is correctly checked out.
1049 </note>
1050 </para></listitem>
1051 <listitem><para>
1052 <emphasis>Edit the Source Files</emphasis>
1053 Follow these steps to make some simple changes to the source
1054 files:
1055 <orderedlist>
1056 <listitem><para>
1057 <emphasis>Change the working directory</emphasis>:
1058 In the previous step, the output noted where you can find
1059 the source files (e.g.
1060 <filename>~/poky_sdk/workspace/sources/linux-yocto</filename>).
1061 Change to where the kernel source code is before making
1062 your edits to the <filename>calibrate.c</filename> file:
1063 <literallayout class='monospaced'>
1064 $ cd ~/poky_sdk/workspace/sources/linux-yocto
1065 </literallayout> 1038 </literallayout>
1066 </para></listitem> 1039 You can safely ignore these messages.
1067 <listitem><para> 1040 The source code is correctly checked out.
1068 <emphasis>Edit the source file</emphasis>: 1041 </note>
1069 Edit the <filename>init/calibrate.c</filename> file to have 1042 </para></listitem>
1070 the following changes: 1043 <listitem><para>
1071 <literallayout class='monospaced'> 1044 <emphasis>Edit the Source Files</emphasis>
1045 Follow these steps to make some simple changes to the source
1046 files:
1047 <orderedlist>
1048 <listitem><para>
1049 <emphasis>Change the working directory</emphasis>:
1050 In the previous step, the output noted where you can find
1051 the source files (e.g.
1052 <filename>~/poky_sdk/workspace/sources/linux-yocto</filename>).
1053 Change to where the kernel source code is before making
1054 your edits to the <filename>calibrate.c</filename> file:
1055 <literallayout class='monospaced'>
1056 $ cd ~/poky_sdk/workspace/sources/linux-yocto
1057 </literallayout>
1058 </para></listitem>
1059 <listitem><para>
1060 <emphasis>Edit the source file</emphasis>:
1061 Edit the <filename>init/calibrate.c</filename> file to have
1062 the following changes:
1063 <literallayout class='monospaced'>
1072 void calibrate_delay(void) 1064 void calibrate_delay(void)
1073 { 1065 {
1074 unsigned long lpj; 1066 unsigned long lpj;
@@ -1085,110 +1077,111 @@
1085 . 1077 .
1086 . 1078 .
1087 . 1079 .
1088 </literallayout> 1080 </literallayout>
1089 </para></listitem> 1081 </para></listitem>
1090 </orderedlist> 1082 </orderedlist>
1091 </para></listitem> 1083 </para></listitem>
1092 <listitem><para> 1084 <listitem><para>
1093 <emphasis>Build the Updated Kernel Source:</emphasis> 1085 <emphasis>Build the Updated Kernel Source:</emphasis>
1094 To build the updated kernel source, use 1086 To build the updated kernel source, use
1095 <filename>devtool</filename>: 1087 <filename>devtool</filename>:
1096 <literallayout class='monospaced'> 1088 <literallayout class='monospaced'>
1097 $ devtool build linux-yocto 1089 $ devtool build linux-yocto
1098 </literallayout> 1090 </literallayout>
1099 </para></listitem> 1091 </para></listitem>
1100 <listitem><para> 1092 <listitem><para>
1101 <emphasis>Create the Image With the New Kernel:</emphasis> 1093 <emphasis>Create the Image With the New Kernel:</emphasis>
1102 Use the <filename>devtool build-image</filename> command 1094 Use the <filename>devtool build-image</filename> command
1103 to create a new image that has the new kernel. 1095 to create a new image that has the new kernel.
1104 <note> 1096 <note>
1105 If the image you originally created resulted in a Wic 1097 If the image you originally created resulted in a Wic
1106 file, you can use an alternate method to create the new 1098 file, you can use an alternate method to create the new
1107 image with the updated kernel. 1099 image with the updated kernel.
1108 For an example, see the steps in the 1100 For an example, see the steps in the
1109 <ulink url='https://wiki.yoctoproject.org/wiki/TipsAndTricks/KernelDevelopmentWithEsdk'>TipsAndTricks/KernelDevelopmentWithEsdk</ulink> 1101 <ulink url='https://wiki.yoctoproject.org/wiki/TipsAndTricks/KernelDevelopmentWithEsdk'>TipsAndTricks/KernelDevelopmentWithEsdk</ulink>
1110 Wiki Page. 1102 Wiki Page.
1111 </note> 1103 </note>
1112 <literallayout class='monospaced'> 1104 <literallayout class='monospaced'>
1113 $ cd ~ 1105 $ cd ~
1114 $ devtool build-image core-image-minimal 1106 $ devtool build-image core-image-minimal
1115 </literallayout> 1107 </literallayout>
1116 </para></listitem> 1108 </para></listitem>
1117 <listitem><para> 1109 <listitem><para>
1118 <emphasis>Test the New Image:</emphasis> 1110 <emphasis>Test the New Image:</emphasis>
1119 For this example, you can run the new image using QEMU 1111 For this example, you can run the new image using QEMU
1120 to verify your changes: 1112 to verify your changes:
1121 <orderedlist> 1113 <orderedlist>
1122 <listitem><para> 1114 <listitem><para>
1123 <emphasis>Boot the image</emphasis>: 1115 <emphasis>Boot the image</emphasis>:
1124 Boot the modified image in the QEMU emulator 1116 Boot the modified image in the QEMU emulator
1125 using this command: 1117 using this command:
1126 <literallayout class='monospaced'> 1118 <literallayout class='monospaced'>
1127 $ runqemu qemux86 1119 $ runqemu qemux86
1128 </literallayout> 1120 </literallayout>
1129 </para></listitem> 1121 </para></listitem>
1130 <listitem><para> 1122 <listitem><para>
1131 <emphasis>Verify the changes</emphasis>: 1123 <emphasis>Verify the changes</emphasis>:
1132 Log into the machine using <filename>root</filename> 1124 Log into the machine using <filename>root</filename>
1133 with no password and then use the following shell 1125 with no password and then use the following shell
1134 command to scroll through the console's boot output. 1126 command to scroll through the console's boot output.
1135 <literallayout class='monospaced'> 1127 <literallayout class='monospaced'>
1136 # dmesg | less 1128 # dmesg | less
1137 </literallayout> 1129 </literallayout>
1138 You should see the results of your 1130 You should see the results of your
1139 <filename>printk</filename> statements 1131 <filename>printk</filename> statements
1140 as part of the output when you scroll down the 1132 as part of the output when you scroll down the
1141 console window. 1133 console window.
1142 </para></listitem> 1134 </para></listitem>
1143 </orderedlist> 1135 </orderedlist>
1144 </para></listitem> 1136 </para></listitem>
1145 <listitem><para> 1137 <listitem><para>
1146 <emphasis>Stage and commit your changes</emphasis>: 1138 <emphasis>Stage and commit your changes</emphasis>:
1147 Within your eSDK terminal, change your working directory to 1139 Within your eSDK terminal, change your working directory to
1148 where you modified the <filename>calibrate.c</filename> 1140 where you modified the <filename>calibrate.c</filename>
1149 file and use these Git commands to stage and commit your 1141 file and use these Git commands to stage and commit your
1150 changes: 1142 changes:
1151 <literallayout class='monospaced'> 1143 <literallayout class='monospaced'>
1152 $ cd ~/poky_sdk/workspace/sources/linux-yocto 1144 $ cd ~/poky_sdk/workspace/sources/linux-yocto
1153 $ git status 1145 $ git status
1154 $ git add init/calibrate.c 1146 $ git add init/calibrate.c
1155 $ git commit -m "calibrate: Add printk example" 1147 $ git commit -m "calibrate: Add printk example"
1156 </literallayout> 1148 </literallayout>
1157 </para></listitem> 1149 </para></listitem>
1158 <listitem><para> 1150 <listitem><para>
1159 <emphasis>Export the Patches and Create a <filename>.bbappend</filename>:</emphasis> 1151 <emphasis>Export the Patches and Create an Append File:</emphasis>
1160 To export your commits as patches and create a 1152 To export your commits as patches and create a
1161 <filename>.bbappend</filename> file, use the following 1153 <filename>.bbappend</filename> file, use the following
1162 command in the terminal used to work with the extensible 1154 command in the terminal used to work with the extensible
1163 SDK. 1155 SDK.
1164 This example uses the previously established layer named 1156 This example uses the previously established layer named
1165 <filename>meta-mylayer</filename>. 1157 <filename>meta-mylayer</filename>.
1166 <note> 1158 <note>
1167 See Step 3 of the 1159 See Step 3 of the
1168 "<link linkend='getting-ready-to-develop-using-devtool'>Getting Ready to Develop using devtool</link>" 1160 "<link linkend='getting-ready-to-develop-using-devtool'>Getting Ready to Develop using devtool</link>"
1169 section for information on setting up this layer. 1161 section for information on setting up this layer.
1170 </note> 1162 </note>
1171 <literallayout class='monospaced'> 1163 <literallayout class='monospaced'>
1172 $ devtool finish linux-yocto /path/to/meta-mylayer 1164 $ devtool finish linux-yocto ~/meta-mylayer
1173 </literallayout> 1165 </literallayout>
1174 Once the command finishes, the patches and the 1166 Once the command finishes, the patches and the
1175 <filename>.bbappend</filename> file are located in the 1167 <filename>.bbappend</filename> file are located in the
1176 <filename>~/meta-mylayer/recipes-kernel/linux</filename> 1168 <filename>~/meta-mylayer/recipes-kernel/linux</filename>
1177 directory. 1169 directory.
1178 </para></listitem> 1170 </para></listitem>
1179 <listitem><para> 1171 <listitem><para>
1180 <emphasis>Build the Image With Your Modified Kernel:</emphasis> 1172 <emphasis>Build the Image With Your Modified Kernel:</emphasis>
1181 You can now build an image that includes your kernel 1173 You can now build an image that includes your kernel
1182 patches. 1174 patches.
1183 Execute the following command from your 1175 Execute the following command from your
1184 <ulink url='&YOCTO_DOCS_REF_URL;#build-directory'>Build Directory</ulink> 1176 <ulink url='&YOCTO_DOCS_REF_URL;#build-directory'>Build Directory</ulink>
1185 in the terminal set up to run BitBake: 1177 in the terminal set up to run BitBake:
1186 <literallayout class='monospaced'> 1178 <literallayout class='monospaced'>
1187 $ cd ~/poky/build 1179 $ cd ~/poky/build
1188 $ bitbake core-image-minimal 1180 $ bitbake core-image-minimal
1189 </literallayout> 1181 </literallayout>
1190 </para></listitem> 1182 </para></listitem>
1191 </orderedlist> 1183 </orderedlist>
1184 </para>
1192 </section> 1185 </section>
1193 1186
1194 <section id="using-traditional-kernel-development-to-patch-the-kernel"> 1187 <section id="using-traditional-kernel-development-to-patch-the-kernel">
@@ -1441,8 +1434,8 @@
1441 following sequence of commands: 1434 following sequence of commands:
1442 <literallayout class='monospaced'> 1435 <literallayout class='monospaced'>
1443 $ cd ~/poky/build 1436 $ cd ~/poky/build
1444 $ cd bitbake -c cleanall yocto-linux 1437 $ bitbake -c cleanall yocto-linux
1445 $ cd bitbake core-image-minimal -c cleanall 1438 $ bitbake core-image-minimal -c cleanall
1446 $ bitbake core-image-minimal 1439 $ bitbake core-image-minimal
1447 $ runqemu qemux86 1440 $ runqemu qemux86
1448 </literallayout> 1441 </literallayout>