Changes between Version 37 and Version 38 of buildroot

Timestamp:

12/12/2020 01:39:00 AM (4 years ago)

Author:

Tim Harvey

Comment:

update venice example to use minimal kernel config

buildroot

@@ -205 +205 @@
 [=#venice]
 == Venice (IMX8MM)
-The following details pertain to buildroot 2018.10 although newer versions will likely be similar if not the same.
+The following details pertain to buildroot 2020.08 although newer versions will likely be similar if not the same.
 
 The Venice product family is based on the i.MX8MM SoC which has 4x Cortex-A53 CPU cores. Therefore the 'BR2_aarch64' is really the only important configuration which produces binaries executable on arm64 CPU's.
@@ -218 +218 @@
 EOF
 make venice_minimal_defconfig
-make
+make -j8
 }}}
 
 This builds output/images/root.tar.xz consisting of a ~1.7MiB root filesystem (when uncompressed) in 5 to 10 minutes of building on a typical Linux desktop.
 
-If you also want buildroot to build a Gateworks v5.4.45 kernel with the minimal root filesystem attached as an initrd you would add the following the your defconfig:
+If you also want buildroot to build a Gateworks v5.4.45 kernel with a minimal kernel config and a self-contained minimal root filesystem you would use the following:
 {{{#!bash
 cat << EOF > configs/venice_kernel_defconfig
@@ -235 +235 @@
 BR2_LINUX_KERNEL_CUSTOM_REPO_URL="https://github.com/Gateworks/linux-venice.git"
 BR2_LINUX_KERNEL_CUSTOM_REPO_VERSION="v5.4.45-venice"
-BR2_LINUX_KERNEL_DEFCONFIG="imx8mm_venice"
+BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG=y
+BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="venice_minimal_kernel_defconfig"
 # filesystem options
+BR2_TARGET_ROOTFS_INITRAMFS=y
 BR2_TARGET_ROOTFS_TAR_XZ=y
 EOF
+# fetch minimal kernel config for venice
+wget http://dev.gateworks.com/buildroot/venice/minimal/venice_minimal_kernel_defconfig
 make venice_kernel_defconfig
-make
-}}}
-
-This produces a ~23MB output/images/Image in 5 to 10 minutes of building on a typical Linux desktop. This is a kernel Image containing the root filesystem in a ramdisk. This is a really easy way to get a read-only minimal Linux image that boots fast and does not access flash storage.
-
-To boot this kernel image on a Venice board via the bootloader with a tftpserver:
+make -j8
+}}}
+
+This produces a ~10MB output/images/Image in 10 to 15 minutes of building on a typical Linux desktop. This is a kernel Image containing the root filesystem in a ramdisk. This is a really easy way to get a read-only minimal Linux image that boots fast and does not access flash storage.
+
+If you need add back or modify kernel features you can do so with:
+{{{#!bash
+make linux-menuconfig # make your changes
+make -j8
+# save and update the defconfig once you are happy with it
+make linux-savedefconfig linux-update-defconfig
+}}}
+
+You can boot a Kernel+ramdisk via U-Boot like this:
+ * load from network tftpserver
 {{{#!bash
 tftpboot $kernel_addr_r Image && booti $kernel_addr_r - $fdtcontroladdr
 }}}
-
-Now you have a minimal Linux OS that booted in about 6 seconds.
+ * load from microSD with ext/fat filesystem
+{{{#!bash
+load mmc 1:1 $kernel_addr_r Image && booti $kernel_addr_r - $fdtcontroladdr
+}}}
+ * load from USB with ext/fat filesystem
+{{{#!bash
+usb start; load usb 0:1 $kernel_addr_r Image && booti $kernel_addr_r - $fdtcontroladdr
+}}}
 
 A prebuilt image can be found [http://dev.gateworks.com/buildroot/venice/minimal here] which contains:
@@ -266 +285 @@
  * evtest (BR2_PACKAGE_EVTEST)
 
-You can boot a Kernel+ramdisk via U-Boot like this:
- * load from network tftpserver
-{{{#!bash
-tftpboot $kernel_addr_r Image && booti $kernel_addr_r - $fdtcontroladdr
-}}}
- * load from microSD with ext/fat filesystem
-{{{#!bash
-load mmc 1:1 $kernel_addr_r Image && booti $kernel_addr_r - $fdtcontroladdr
-}}}
- * load from USB with ext/fat filesystem
-{{{#!bash
-usb start; load usb 0:1 $kernel_addr_r Image && booti $kernel_addr_r - $fdtcontroladdr
-}}}
 
 [=#newport]
@@ -461 +467 @@
 BR2_LINUX_KERNEL_CUSTOM_REPO_URL="https://github.com/Gateworks/linux-imx6.git"
 BR2_LINUX_KERNEL_CUSTOM_REPO_VERSION="gateworks_5.4.45"
-BR2_LINUX_KERNEL_DEFCONFIG="gwventana"
+BR2_LINUX_KERNEL_USE_CUSTOM_CONFIG=y
+BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE="gwventana_minimal_kernel_defconfig"
 # filesystem options
 BR2_TARGET_ROOTFS_TAR_XZ=y
+BR2_TARGET_ROOTFS_INITRAMFS=y
 EOF
 # fetch minimal kernel config for ventana