doc: board: Convert README.zynq to reST

Convert plain text documentation to reStructuredText format and add
it to Sphinx TOC tree. No essential content change.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

doc/board/index.rst

@@ -15,3 +15,4 @@ Board-specific doc
    intel/index
    renesas/index
    sifive/index
+   xilinx/index

doc/board/xilinx/zynq.rst

@@ -1,15 +1,17 @@
-# SPDX-License-Identifier: GPL-2.0+
-#
-# Xilinx ZYNQ U-Boot
-#
-# (C) Copyright 2013 Xilinx, Inc.
+.. SPDX-License-Identifier: GPL-2.0+
+..  (C) Copyright 2013 Xilinx, Inc.
 
-1. About this
+ZYNQ
+====
+
+About this
+----------
 
 This document describes the information about Xilinx Zynq U-Boot -
 like supported boards, ML status and TODO list.
 
-2. Zynq boards
+Zynq boards
+-----------
 
 Xilinx Zynq-7000 All Programmable SoCs enable extensive system level
 differentiation, integration, and flexibility through hardware, software,
@@ -20,18 +22,21 @@ and I/O programmability.
 * 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)
+     - zc770-xm010 (single qspi, gem0, mmc)
+     - zc770-xm011 (8 or 16 bit nand)
+     - zc770-xm012 (nor)
+     - zc770-xm013 (dual parallel qspi, gem1)
 
-3. Building
+Building
+--------
+
+configure and build for zc702 board::
 
- ex. configure and build for zc702 board
    $ make zynq_zc702_config
    $ make
 
-4. Bootmode
+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]
@@ -44,40 +49,47 @@ 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
+
+.. code-block:: c
+
+   #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
+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/raw/zynq_nand.c
+
+  :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/raw/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
+TODO
+----
 
-- Add FDT support on individual drivers
+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
+* [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
+
+.. Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
+.. Sun Dec 15 14:52:41 IST 2013