[PATCH 0/2] board/raspberrypi: add a genimage config (based on 8d00fe4)

rpi_genimage.patch

From 9c91753518e813ad96c3ec4d225f4545cff826e3 Mon Sep 17 00:00:00 2001
From: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Date: Mon, 16 Mar 2015 00:21:31 -0400
Subject: [PATCH 1/2] board/raspberrypi: install Device Tree

Add a post-image script to Raspberry Pi configs with a Device Tree
(raspberrypi_dt and raspberrypi2), which calls the mkknlimg tool on the
resulting zImage kernel, in order to install the Device Tree as
described in the board readme file.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
---
 board/raspberrypi/mark-dt.sh     | 9 +++++++++
 configs/raspberrypi2_defconfig   | 1 +
 configs/raspberrypi_dt_defconfig | 1 +
 3 files changed, 11 insertions(+)
 create mode 100755 board/raspberrypi/mark-dt.sh

diff --git a/board/raspberrypi/mark-dt.sh b/board/raspberrypi/mark-dt.sh
new file mode 100755
index 0000000..4852565
--- /dev/null
+++ b/board/raspberrypi/mark-dt.sh
@@ -0,0 +1,9 @@
+#!/bin/bash
+
+# Merely appends a marker at the end of the kernel image, which instructs the
+# RPi bootloader that the kernel is Device Tree aware, and thus the bootloader
+# will load the device tree blobs; if the marker is missing, the bootloader
+# will not load a device tree blob, and will pass ATAGS.
+
+mkknlimg "${BINARIES_DIR}/zImage" "${BINARIES_DIR}/zImage-dt"
+mv "${BINARIES_DIR}/zImage-dt" "${BINARIES_DIR}/zImage"
diff --git a/configs/raspberrypi2_defconfig b/configs/raspberrypi2_defconfig
index b523a4a..306ebef 100644
--- a/configs/raspberrypi2_defconfig
+++ b/configs/raspberrypi2_defconfig
@@ -23,3 +23,4 @@ BR2_LINUX_KERNEL_ZIMAGE=y
 # Install the DTB files, as the RPi2 uses the Device Tree
 BR2_PACKAGE_RPI_FIRMWARE=y
 BR2_PACKAGE_RPI_FIRMWARE_INSTALL_DTBS=y
+BR2_ROOTFS_POST_IMAGE_SCRIPT="board/raspberrypi2/mark-dt.sh"
diff --git a/configs/raspberrypi_dt_defconfig b/configs/raspberrypi_dt_defconfig
index ca62084..bcf5598 100644
--- a/configs/raspberrypi_dt_defconfig
+++ b/configs/raspberrypi_dt_defconfig
@@ -20,3 +20,4 @@ BR2_LINUX_KERNEL_ZIMAGE=y
 # Install the DTB files
 BR2_PACKAGE_RPI_FIRMWARE=y
 BR2_PACKAGE_RPI_FIRMWARE_INSTALL_DTBS=y
+BR2_ROOTFS_POST_IMAGE_SCRIPT="board/raspberrypi/mark-dt.sh"
-- 
2.5.0


From 79b3f9be9229d843e2e2e957982529a7c3b93635 Mon Sep 17 00:00:00 2001
From: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Date: Thu, 16 Apr 2015 18:36:33 -0400
Subject: [PATCH 2/2] board/raspberrypi: add a genimage config

This patch adds a genimage config file and a post-image script for the
Raspberry Pi models, to generate a medium image "sdcard.img", ready to
be booted.

The image contains the persistent layout explained in the board
readme.txt file: a vfat partition for the kernel, DT and firmware files,
and a Ext4 rootfs partition.

The defconfigs have been slightly changed to enable this feature. Also
lighten the readme file since the config file is documented and simpler.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
---
 board/raspberrypi/genimage.cfg   |  56 ++++++++++++++
 board/raspberrypi/genimage.sh    |  13 ++++
 board/raspberrypi/readme.txt     | 154 ++++-----------------------------------
 configs/raspberrypi2_defconfig   |   3 +-
 configs/raspberrypi_defconfig    |   2 +
 configs/raspberrypi_dt_defconfig |   3 +-
 6 files changed, 88 insertions(+), 143 deletions(-)
 create mode 100644 board/raspberrypi/genimage.cfg
 create mode 100755 board/raspberrypi/genimage.sh

diff --git a/board/raspberrypi/genimage.cfg b/board/raspberrypi/genimage.cfg
new file mode 100644
index 0000000..4757f62
--- /dev/null
+++ b/board/raspberrypi/genimage.cfg
@@ -0,0 +1,56 @@
+# Minimal SD card image for the Raspberry Pi
+#
+# The SD card must have at least a bootable VFAT partition containing the
+# firmware files, the kernel, and optionally the device tree blob.
+#
+# This image defines a persistent rootfs partition. If you prefer a
+# volatile rootfs, you have to slightly adjust the configuration:
+#
+#     $ make menuconfig
+#         * Select "Filesystem images"
+#         * Select "initial RAM filesystem linked into linux kernel"
+#
+# You may also deselect "tar the root filesystem". Then adjust the
+# boot.vfat image size to at least 50M and remove the rootfs partition
+# definition below.
+#
+# For more information, visit
+# http://elinux.org/RPi_Advanced_Setup#Advanced_SD_card_setup
+
+image boot.vfat {
+  vfat {
+    files = {
+      # Mandatory RPi firmware files
+      "rpi-firmware/bootcode.bin",
+      "rpi-firmware/config.txt",
+      "rpi-firmware/fixup.dat",
+      "rpi-firmware/start.elf",
+
+      # Device Tree Blobs, for dt-marked kernels
+      "rpi-firmware/bcm2708-rpi-b.dtb",
+      "rpi-firmware/bcm2708-rpi-b-plus.dtb",
+      "rpi-firmware/bcm2709-rpi-2-b.dtb",
+
+      # Kernel, optionally marked for DT-enabled configs (see mkknlimg)
+      "zImage"
+    }
+  }
+  size = 10M
+}
+
+image sdcard.img {
+  hdimage {
+  }
+
+  partition boot {
+    partition-type = 0xC
+    bootable = "true"
+    image = "boot.vfat"
+  }
+
+  partition rootfs {
+    partition-type = 0x83
+    image = "rootfs.ext4"
+    size = 512M
+  }
+}
diff --git a/board/raspberrypi/genimage.sh b/board/raspberrypi/genimage.sh
new file mode 100755
index 0000000..77f99e9
--- /dev/null
+++ b/board/raspberrypi/genimage.sh
@@ -0,0 +1,13 @@
+#!/bin/bash
+
+GENIMAGE_CFG="board/raspberrypi/genimage.cfg"
+GENIMAGE_TMP="${BUILD_DIR}/genimage.tmp"
+
+rm -rf "${GENIMAGE_TMP}"
+
+genimage \
+  --rootpath "${TARGET_DIR}" \
+  --tmppath "${GENIMAGE_TMP}" \
+  --inputpath "${BINARIES_DIR}" \
+  --outputpath "${BINARIES_DIR}" \
+  --config "${GENIMAGE_CFG}"
diff --git a/board/raspberrypi/readme.txt b/board/raspberrypi/readme.txt
index b513ca3..d2f5d1f 100644
--- a/board/raspberrypi/readme.txt
+++ b/board/raspberrypi/readme.txt
@@ -1,153 +1,25 @@
 Raspberry Pi
 
-Intro
-=====
+https://www.raspberrypi.org/
 
-These instructions apply to all models of the Raspberry Pi:
+Buildroot supports all Raspberry Pi models:
   - the original models A and B,
   - the "enhanced" models A+ and B+,
   - the model B2 (aka Raspberry Pi 2).
 
-To be able to use your Raspberry Pi board with the images generated by
-Buildroot, you have to choose whether you will use:
+To build a minimal support for one of these boards, run:
 
-    * Volatile rootfs in RAM (the rootfs is an initramfs) or
-    * Persistent rootfs on the SDCard
+    $ make <model>_defconfig
+    $ make
 
-Also, a good source of information is http://elinux.org/R-Pi_Hub
+Where <model> is one of:
 
-How to build it
-===============
+  - "raspberrypi" for A, B, A+ and B+ models,
+  - "raspberrypi_dt" for previous models with device tree support,
+  - "raspberrypi2" for the B2 model (implies device tree support).
 
-Configure Buildroot
--------------------
+Buildroot prepares a bootable "sdcard.img" image in the output/images/
+directory, ready to be dumped on an SD card.
 
-The raspberrypi_defconfig configuration is a minimal configuration with
-all that is required to bring the Raspberry Pi. You should base your
-work on this defconfig:
-
-  $ make raspberrypi_defconfig
-
-Alternatively, if you want to test support for the Device Tree:
-
-  $ make raspberrypi_dt_defconfig
-
-If you want to use a persistent rootfs, skip to "Build the rootfs", below.
-
-For a volatile rootfs, you have to slightly adjust the configuration:
-
-  $ make menuconfig
-    * Select "Filesystem images"
-    * Select "initial RAM filesystem linked into linux kernel"
-
-You may also deselect "tar the root filesystem".
-
-Build the rootfs
-----------------
-
-Note: you will need to have access to the network, since Buildroot will
-download the packages' sources.
-
-You may now build your rootfs with:
-
-  $ make
-
-(This may take a while; consider getting yourself a coffee ;-) )
-
-Result of the build
--------------------
-
-After building, you should obtain this tree:
-
-    output/images/
-    +-- rootfs.tar                              [0]
-    +-- rpi-firmware/
-    |   +-- bcm2708-rpi-b.dtb
-    |   +-- bcm2708-rpi-b-plus.dtb
-    |   +-- bcm2709-rpi-2-b.dtb
-    |   +-- bootcode.bin
-    |   +-- config.txt
-    |   +-- fixup.dat
-    |   `-- start.elf
-    `-- zImage
-
-[0] Note for Volatile: rootfs.tar will only be there if you kept
-    "tar the root filesystem" option selected in "Filesystem images".
-
-Prepare you SDCard
-==================
-
-For more information, visit
-http://elinux.org/RPi_Advanced_Setup#Advanced_SD_card_setup
-
-In summary, your SDCard must have first partition in fat32 and marked bootable.
-
-Create the required partitions:
-  - for a persistent rootfs, 10MiB is enough memory for the boot fat32
-    partition, and a second partition is required for the root filesystem
-  - for a volatile rootfs, 50MiB is required for the boot fat32 partition
-
-Note: You can create any number of partitions you desire, the only requirement
-is that the first partition must be using fat32 and be bootable.
-
-Mount the partitions (adjust 'sdX' to match your SDcard device):
-
-  $ sudo mount /dev/sdX1 /mnt/mountpointboot
-  $ sudo mount /dev/sdX2 /mnt/mountpointroot    (only for persistent rootfs)
-
-Install the binaries to the SDCard
-----------------------------------
-
-At the root of the boot partition, the Raspberry Pi must find the following
-files:
-
-    * bcm2708-rpi-b.dtb         [1]
-    * bcm2708-rpi-b-plus.dtb    [2]
-    * bcm2709-rpi-2-b.dtb       [3]
-    * bootcode.bin
-    * config.txt
-    * fixup.dat
-    * start.elf
-    * zImage
-
-[1] For models A and B
-[2] For models A+ and B+
-[3] For model 2
-
-For example:
-
- $ cp output/images/rpi-firmware/* /mnt/mountpointboot
-
-If your kernel does *not* have support for the Device Tree, then install
-it with:
-
- $ cp output/images/zImage /mnt/mountpointboot
-
-If your kernel *does* have support for the Device Tree, then install it
-with:
-
-  $ ./output/host/usr/bin/mkknlimg output/images/zImage /mnt/mountpointboot/zImage
-
-Note: The kernel image file name is defined in config.txt like this:
-kernel=zImage
-
-If you use a volatile rootfs, Skip to "Finish", below. For a persistent
-rootfs, there are further steps to do.
-
-Extract (as root!) the contents of the rootfs.tar archive into the second
-partition you created above:
-
-  $ sudo tar xf ./output/images/rootfs.tar -C /mnt/mountpointroot
-
-Finish
-======
-
-Unmount all the partitions:
-
-  $ sudo umount /mnt/mountpointboot
-  $ sudo umount /mnt/mountpointroot     (only for persistent rootfs)
-
-And eject your SDcard from your computer SDcard reader.
-
-Insert the SDcard into your Raspberry Pi, and power it up. Your new system
-should come up, now.
+For details about the medium image layout, see the definition in
+board/raspberrypi/genimage.cfg.
diff --git a/configs/raspberrypi2_defconfig b/configs/raspberrypi2_defconfig
index 306ebef..bdfed13 100644
--- a/configs/raspberrypi2_defconfig
+++ b/configs/raspberrypi2_defconfig
@@ -23,4 +23,5 @@ BR2_LINUX_KERNEL_ZIMAGE=y
 # Install the DTB files, as the RPi2 uses the Device Tree
 BR2_PACKAGE_RPI_FIRMWARE=y
 BR2_PACKAGE_RPI_FIRMWARE_INSTALL_DTBS=y
-BR2_ROOTFS_POST_IMAGE_SCRIPT="board/raspberrypi2/mark-dt.sh"
+BR2_PACKAGE_HOST_GENIMAGE=y
+BR2_ROOTFS_POST_IMAGE_SCRIPT="board/raspberrypi2/mark-dt.sh board/raspberrypi2/genimage.sh"
diff --git a/configs/raspberrypi_defconfig b/configs/raspberrypi_defconfig
index 835657c..5029b53 100644
--- a/configs/raspberrypi_defconfig
+++ b/configs/raspberrypi_defconfig
@@ -7,6 +7,8 @@ BR2_TOOLCHAIN_BUILDROOT_CXX=y
 BR2_TARGET_GENERIC_GETTY_PORT="tty1"
 
 BR2_PACKAGE_RPI_FIRMWARE=y
+BR2_PACKAGE_HOST_GENIMAGE=y
+BR2_ROOTFS_POST_IMAGE_SCRIPT="board/raspberrypi/genimage.sh"
 
 # Lock to 3.12 headers as the RPi kernel is based off the 3.12 branch
 BR2_KERNEL_HEADERS_VERSION=y
diff --git a/configs/raspberrypi_dt_defconfig b/configs/raspberrypi_dt_defconfig
index bcf5598..93d7620 100644
--- a/configs/raspberrypi_dt_defconfig
+++ b/configs/raspberrypi_dt_defconfig
@@ -20,4 +20,5 @@ BR2_LINUX_KERNEL_ZIMAGE=y
 # Install the DTB files
 BR2_PACKAGE_RPI_FIRMWARE=y
 BR2_PACKAGE_RPI_FIRMWARE_INSTALL_DTBS=y
-BR2_ROOTFS_POST_IMAGE_SCRIPT="board/raspberrypi/mark-dt.sh"
+BR2_PACKAGE_HOST_GENIMAGE=y
+BR2_ROOTFS_POST_IMAGE_SCRIPT="board/raspberrypi/mark-dt.sh board/raspberrypi/genimage.sh"
-- 
2.5.0