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-rw-r--r--doc/README.clang56
-rw-r--r--doc/README.odroid143
-rw-r--r--doc/device-tree-bindings/video/exynos-fb.txt6
3 files changed, 205 insertions, 0 deletions
diff --git a/doc/README.clang b/doc/README.clang
new file mode 100644
index 00000000000..9ad689f071b
--- /dev/null
+++ b/doc/README.clang
@@ -0,0 +1,56 @@
+The biggest problem when trying to compile U-boot with clang is that
+almost all archs rely on storing gd in a global register and clang user
+manual states: "clang does not support global register variables; this
+is unlikely to be implemented soon because it requires additional LLVM
+backend support."
+
+Since version 3.4 the ARM backend can be instructed to leave r9 alone.
+Global registers themselves are not supported so some inline assembly is
+used to get its value. This does lead to larger code then strictly
+necessary, but at least works.
+
+NOTE: target compilation only work for _some_ ARM boards at the moment.
+Also Aarch64 is not supported: Most notably boards which aren't using
+the generic board will fail to compile, but since those are expected
+to be converted this will solve itself. Boards which reassign gd in c
+will also fail to compile, but there is in no strict reason to do so
+in the ARM world, since crt0.S takes care of this. These assignments
+can be avoided by changing the init calls but this is not in mainline yet.
+
+NOTE: without the -mllvm -arm-use-movt=0 flags u-boot will compile
+fine, but llvm might hardcode addresses in movw / movt pairs, which
+cannot be relocated and u-boot will fail at runtime.
+
+Debian (based)
+--------------
+Binary packages can be installed as usual, e.g.:
+sudo apt-get install clang
+
+To compile U-Boot with clang on linux without IAS use e.g.:
+export TRIPLET=arm-linux-gnueabi && export CROSS_COMPILE="$TRIPLET-"
+make HOSTCC=clang CC="clang -target $TRIPLET -mllvm -arm-use-movt=0 -no-integrated-as" rpi_b_defconfig
+make HOSTCC=clang CC="clang -target $TRIPLET -mllvm -arm-use-movt=0 -no-integrated-as" all V=1 -j8
+
+FreeBSD 11 (Current):
+--------------------
+Since llvm 3.4 is currently in the base system, the integrated as is
+incapable of building U-Boot. Therefore gas from devel/arm-eabi-binutils
+is used instead. It needs a symlinks to be picked up correctly though:
+
+ln -s /usr/local/bin/arm-eabi-as /usr/bin/arm-freebsd-eabi-as
+
+# The following commands compile U-Boot using the clang xdev toolchain.
+# NOTE: CROSS_COMPILE and target differ on purpose!
+export CROSS_COMPILE=arm-eabi-
+gmake CC="clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0" rpi_b_defconfig
+gmake CC="clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0" -j8
+
+Given that u-boot will default to gcc, above commands can be
+simplified with a simple wrapper script, listed below.
+
+/usr/local/bin/arm-eabi-gcc
+---
+#!/bin/sh
+
+exec clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0 "$@"
+
diff --git a/doc/README.odroid b/doc/README.odroid
new file mode 100644
index 00000000000..528bb952795
--- /dev/null
+++ b/doc/README.odroid
@@ -0,0 +1,143 @@
+ U-boot for Odroid X2/U3
+========================
+
+1. Summary
+==========
+This is a quick instruction for setup Odroid boards based on Exynos4412.
+Board config: odroid_config
+
+2. Supported devices
+====================
+This U-BOOT config can be used on two boards:
+- Odroid U3
+- Odroid X2
+with CPU Exynos 4412 rev 2.0 and 2GB of RAM
+
+3. Boot sequence
+================
+iROM->BL1->(BL2 + TrustZone)->U-BOOT
+
+This version of U-BOOT doesn't implement SPL but it is required(BL2)
+and can be found in "boot.tar.gz" from here:
+http://dev.odroid.com/projects/4412boot/wiki/FrontPage?action=download&value=boot.tar.gz
+or here:
+http://odroid.in/guides/ubuntu-lfs/boot.tar.gz
+
+4. Boot media layout
+====================
+The table below shows SD/eMMC cards layout for U-boot.
+The block offset is starting from 0 and the block size is 512B.
+ -------------------------------------
+| Binary | Block offset| part type |
+| name | SD | eMMC |(eMMC only)|
+ -------------------------------------
+| Bl1 | 1 | 0 | 1 (boot) |
+| Bl2 | 31 | 30 | 1 (boot) |
+| U-boot | 63 | 62 | 1 (boot) |
+| Tzsw | 2111 | 2110 | 1 (boot) |
+| Uboot Env | 2500 | 2500 | 0 (user) |
+ -------------------------------------
+
+5. Prepare the SD boot card - with SD card reader
+=================================================
+To prepare bootable media you need boot binaries provided by hardkernel.
+File "boot.tar.gz" (link in point 3.) contains:
+- E4412_S.bl1.HardKernel.bin
+- E4412_S.tzsw.signed.bin
+- bl2.signed.bin
+- sd_fusing.sh
+- u-boot.bin
+
+This is all you need to boot this board. But if you want to use your custom
+u-boot then you need to change u-boot.bin with your own u-boot binary*
+and run the script "sd_fusing.sh" - this script is valid only for SD card.
+
+*note:
+The proper binary file of current U-boot is u-boot-dtb.bin.
+
+quick steps for Linux:
+- extract boot.tar.gz
+- put any SD card into the SD reader
+- check the device with "dmesg"
+- run ./sd_fusing.sh /dev/sdX - where X is SD card device (but not a partition)
+Check if Hardkernel U-boot is booting, and next do the same with your U-boot.
+
+6. Prepare the eMMC boot card
+ with a eMMC card reader (boot from eMMC card slot)
+=====================================================
+To boot the device from the eMMC slot you should use a special card reader
+which supports eMMC partiion switch. All of the boot binaries are stored
+on the eMMC boot partition which is normally hidden.
+
+The "sd_fusing.sh" script can be used after updating offsets of binaries
+according to the table from point 4. Be sure that you are working on the right
+eMMC partition - its size is usually very small, about 1-4 MiB.
+
+7. Prepare the eMMC boot card
+ with a SD card reader (boot from SD card slot)
+=================================================
+If you have an eMMC->microSD adapter you can prepare the card as in point 5.
+But then the device can boot only from the SD card slot.
+
+8. Prepare the boot media using Hardkernel U-boot
+=================================================
+You can update the U-boot to the custom one if you have an working bootloader
+delivered with the board on a eMMC/SD card. Then follow the steps:
+- install the android fastboot tool
+- connect a micro usb cable to the board
+- on the U-boot prompt, run command: fastboot (as a root)
+- on the host, run command: "fastboot flash bootloader u-boot-dtb.bin"
+- the custom U-boot should start after the board resets.
+
+9. Partition layout
+====================
+Default U-boot environment is setup for fixed partiion layout.
+
+Partition table: MSDOS. Disk layout and files as listed in the table below.
+ ----- ------ ------ ------ -------- ---------------------------------
+| Num | Name | FS | Size | Offset | Reguired files |
+| | | Type | MiB | MiB | |
+ ----- ------ ------ ------ -------- ---------------------------------
+| 1 | BOOT | fat | 100 | 2 | kernel, fdt** |
+| 2 | ROOT | ext4 | - | | any Linux system |
+ ----- ------ ------ ------ -------- ---------------------------------
+
+**note:
+Supported fdt files are:
+- exynos4412-odroidx2.dtb
+- exynos4412-odroidu3.dtb
+
+Supported kernel files are:
+- Image.itb
+- zImage
+- uImage
+
+The default environmental variable "dfu_alt_info" is set* for above layout.
+Each partition size is just an example, dfu_alt_info tries init two partitions.
+The size of each is not important.
+
+*note:
+$dfu_alt_info is set on a boot time and it is concatenated using two variables:
+- $dfu_alt_boot(set dynamically)
+- $dfu_alt_system(from current env).
+
+To add any changes to dfu_alt_info - please modify $dfu_alt_system only.
+Changes are visible after board reset.
+
+10. The environment and booting the kernel
+==========================================
+There are three macros defined in config for various boot options:
+Two for both, kernel with device tree support and also without it:
+- boot_uimg - load uImage
+- boot_zimg - load zImage
+If proper fdt file exists then it will be automatically loaded,
+so for old kernel types, please remove fdt file from boot partition.
+
+The third boot option for multi image support (more info: doc/uImage.FIT/)
+- boot_fit - for binary file: "Image.itb"
+
+Default boot command: "autoboot"
+And the boot sequence is:
+- boot_fit - if "Image.itb" exists
+- boot_zimg - if "zImage" exists
+- boot_uimg - if "uImage" exists
diff --git a/doc/device-tree-bindings/video/exynos-fb.txt b/doc/device-tree-bindings/video/exynos-fb.txt
index bb7441cbbed..dc4e44fbc52 100644
--- a/doc/device-tree-bindings/video/exynos-fb.txt
+++ b/doc/device-tree-bindings/video/exynos-fb.txt
@@ -55,6 +55,12 @@ Board(panel specific):
samsung,pclk-name: parent clock identifier: 1(MPLL), 2(EPLL), 3(VPLL)
samsung,sclk-div: parent_clock/source_clock ratio
samsung,dual-lcd-enabled: 1 if you support two LCD, else 0
+ samsung,disable-sysmmu: Define this if you want to disable FIMD sysmmu.
+ (needed for Exynos5420 and newer versions)
+ Add the required FIMD sysmmu nodes to be
+ disabled with compatible string
+ "samsung,sysmmu-v3.3", with a "reg" property
+ holding the register address of FIMD sysmmu.
Example:
SOC specific part: