zedboard: Update readme.txt to reflect BOOT.BIN generation

Signed-off-by: Jan Viktorin <viktorin@rehivetech.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

board/avnet/zedboard/readme.txt

@@ -5,68 +5,60 @@ System-On-Chip.
 Zedboard information including schematics, reference designs, and manuals are
 available from http://www.zedboard.org .
 
-The U-Boot firmware for the Xilinx Zynq All Programmable SoC depends
+Steps to create a working system for Zedboard:
-on some proprietary code. This dependency consists of a pair of
-files are available from the Xilinx SDK installation.
 
-You will need these files from Xilinx SDK installation to generate
+1) make zedboard_defconfig
-the U-Boot firmware:
+2) make
-	ps7_init.c
+3) copy files BOOT.BIN, u-boot-dtb.img, rootfs.cpio.uboot,
-	ps7_init.h
+	uImage, zynq-zed.dtb into your SD card
+4) boot your Zedboard
 
-Buildroot will create the following files and place them in the
+The expected output:
-<output>/images directory.
-	zynq-zed.dtb
-	rootfs.cpio.uboot
-	uImage
-	u-boot.img
-	boot.bin
 
+ U-Boot SPL 2015.07-rc2 (Jun 18 2015 - 16:42:58)
+ mmc boot
+ reading system.dtb
+ spl_load_image_fat_os: error reading image system.dtb, err - -1
+ reading u-boot-dtb.img
+ reading u-boot-dtb.img
 
-uboot.bin  -- U-Boot SPL w/ Xilinx boot.bin wrapper
+ U-Boot 2015.07-rc2 (Jun 18 2015 - 16:42:58 +0200)
----------------------------------------------------
 
-Due to licensing issues, the files ps7_init.c/h are not able to be
+ Model: Zynq ZED Board
-distributed with the U-Boot source code.  These files are required to make a
+ I2C:   ready
-boot.bin file.
+ DRAM:  ECC disabled 512 MiB
-
+ MMC:   zynq_sdhci: 0
-If you already have the Xilinx tools installed, the following sequence will
+ Using default environment
-unpack, patch and build the rfs, kernel, uboot, and uboot-spl.
+ ...
-
-make zedboard_defconfig
-make uboot-patch
-cp ${XILINX}/ISE_DS/EDK/sw/lib/hwplatform_templates/zed_hw_platform/ps7_init.{c,h} \
-output/build/uboot-xilinx-v2014.1/board/xilinx/zynq/
-
-After copying these files into the U-Boot source tree, you can
-continue the build with:
-
-make
-
-*Notice*
-While the build will successfully complete without the ps7_init.*
-files,  the uboot.bin file generated by this configuration will not
-function properly on the Zedboard.  Therefore, it is imperative that
-the ps7_init.* files be copied into the U-Boot source tree any time
-the clean, or uboot-dirclean targets are made.
 
+When using an older U-Boot then 2015.07, a working ps7_init.c
+file is required to be installed into the U-Boot directory
+structure. From 2015.07, the major Zynq-based boards are
+supported without any manual intervention.
 
 Resulting system
 ----------------
 A FAT32 partition should be created at the beginning of the SD Card
 and the following files should be installed:
-	/boot.bin
+	/BOOT.BIN
-	/devicetree.dtb
+	/zynq-zed.dtb
 	/uImage
-	/uramdisk.image.gz
+	/rootfs-cpio.uboot
-	/u-boot.img
+	/u-boot-dtb.img
 
 
 All needed files can be taken from output/images/
 
-boot.bin, uImage and u-boot.img are direct copies of the same files
+BOOT.BIN, uImage and u-boot-dtb.img are direct copies of the same files
 available on output/images/
 
-devicetree.dtb is just zynq-zed.dtb renamed.
+There is a patch attached that redefines the U-Boot's environment
+to work with Buildroot out-of-the-box.
 
-uramdisk.image.gz is rootfs.cpio.uboot renamed
+You can alter the booting procedure by creating a file uEnv.txt
+in the root of the SD card. It is a plain text file in format
+<key>=<value> one per line:
+
+kernel_image=myimage
+modeboot=myboot
+myboot=...