In the section about Device Trees add a paragraph at the end that
clarifies how we decide of a tree is valid or not. We say that all
bindings must either be in the specification (link provided) or in our
device-tree-bindings directory. We say that most of these come from the
Linux Kernel and as such some design decisions are made for us already,
but that in most cases we wish to retain compatibility.
Cc: Simon Glass <sjg@chromium.org>
Cc: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
# SPDX-License-Identifier: GPL-2.0+
#
# Xilinx ZYNQ U-Boot
#
# (C) Copyright 2013 Xilinx, Inc.
1. About this
This document describes the information about Xilinx Zynq U-Boot -
like supported boards, ML status and TODO list.
2. Zynq boards
Xilinx Zynq-7000 All Programmable SoCs enable extensive system level
differentiation, integration, and flexibility through hardware, software,
and I/O programmability.
* zc702 (single qspi, gem0, mmc) [1]
* zc706 (dual parallel qspi, gem0, mmc) [2]
* zed (single qspi, gem0, mmc) [3]
* microzed (single qspi, gem0, mmc) [4]
* zc770
- zc770-xm010 (single qspi, gem0, mmc)
- zc770-xm011 (8 or 16 bit nand)
- zc770-xm012 (nor)
- zc770-xm013 (dual parallel qspi, gem1)
3. Building
ex. configure and build for zc702 board
$ make zynq_zc702_config
$ make
4. Bootmode
Zynq has a facility to read the bootmode from the slcr bootmode register
once user is setting through jumpers on the board - see page no:1546 on [5]
All possible bootmode values are defined in Table 6-2:Boot_Mode MIO Pins
on [5].
board_late_init() will read the bootmode values using slcr bootmode register
at runtime and assign the modeboot variable to specific bootmode string which
is intern used in autoboot.
SLCR bootmode register Bit[3:0] values
#define ZYNQ_BM_NOR 0x02
#define ZYNQ_BM_SD 0x05
#define ZYNQ_BM_JTAG 0x0
"modeboot" variable can assign any of "norboot", "sdboot" or "jtagboot"
bootmode strings at runtime.
5. Mainline status
- Added basic board configurations support.
- Added zynq u-boot bsp code - arch/arm/cpu/armv7/zynq
- Added zynq boards named - zc70x, zed, microzed, zc770_xm010/xm011/xm012/xm013
- Added zynq drivers:
serial - drivers/serial/serial_zynq.c
net - drivers/net/zynq_gem.c
mmc - drivers/mmc/zynq_sdhci.c
spi - drivers/spi/zynq_spi.c
qspi - drivers/spi/zynq_qspi.c
i2c - drivers/i2c/zynq_i2c.c
nand - drivers/mtd/nand/zynq_nand.c
- Done proper cleanups on board configurations
- Added basic FDT support for zynq boards
- d-cache support for zynq_gem.c
6. TODO
- Add FDT support on individual drivers
[1] http://www.xilinx.com/products/boards-and-kits/EK-Z7-ZC702-G.htm
[2] http://www.xilinx.com/products/boards-and-kits/EK-Z7-ZC706-G.htm
[3] http://zedboard.org/product/zedboard
[4] http://zedboard.org/product/microzed
[5] http://www.xilinx.com/support/documentation/user_guides/ug585-Zynq-7000-TRM.pdf
--
Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
Sun Dec 15 14:52:41 IST 2013