docs: nxp soc-lx2160a based platforms

Addition of documents for platforms based on
NXP SoC LX2160A.

Signed-off-by: Pankaj Gupta <pankaj.gupta@nxp.com>
Change-Id: I39ac5a9eb0b668d26301a0a24a1e6bf87f245f02
diff --git a/docs/plat/nxp/nxp-layerscape.rst b/docs/plat/nxp/nxp-layerscape.rst
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+NXP SoCs - Overview
+=====================
+.. section-numbering::
+    :suffix: .
+
+The QorIQ family of ARM based SoCs that are supported on TF-A are:
+
+1. LX2160ARDB:
+        Platform Name:
+
+        a. lx2160ardb (Board details can be fetched from the link: `lx2160ardb`_)
+
+
+Table of supported boot-modes by each platform & platform that needs FIP-DDR:
+-----------------------------------------------------------------------------
+
++---+-----------------+-------+--------+-------+-------+-------+-------------+--------------+-----------------+
+|   |     BOOT_MODE-->|  sd   |  qspi  |  nor  | nand  | emmc  | flexspi_nor | flexspi_nand | fip_ddr needed  |
+|   |                 |       |        |       |       |       |             |              |                 |
+|   |     PLAT        |       |        |       |       |       |             |              |                 |
++===+=================+=======+========+=======+=======+=======+=============+==============+=================+
+| 1.| lx2160ardb      |  yes  |        |       |       |  yes  |   yes       |              |       yes       |
++---+-----------------+-------+--------+-------+-------+-------+-------------+--------------+-----------------+
+
+Boot Sequence
+-------------
+::
+
++                           Secure World        |     Normal World
++ EL0                                           |
++                                               |
++ EL1                           BL32(Tee OS)    |     kernel
++                                ^ |            |       ^
++                                | |            |       |
++ EL2                            | |            |     BL33(u-boot)
++                                | |            |      ^
++                                | v            |     /
++ EL3        BootROM --> BL2 --> BL31 ---------------/
++
+
+Boot Sequence with FIP-DDR
+--------------------------
+::
+
++                           Secure World        |     Normal World
++ EL0                                           |
++                                               |
++ EL1               fip-ddr     BL32(Tee OS)    |     kernel
++                     ^ |         ^ |           |       ^
++                     | |         | |           |       |
++ EL2                 | |         | |           |     BL33(u-boot)
++                     | |         | |           |      ^
++                     | v         | v           |     /
++ EL3     BootROM --> BL2 -----> BL31 ---------------/
++
+
+
+How to build
+=============
+
+Code Locations
+--------------
+
+-  OP-TEE:
+   `link <https://source.codeaurora.org/external/qoriq/qoriq-components/optee_os>`__
+
+-  U-Boot:
+   `link <https://source.codeaurora.org/external/qoriq/qoriq-components/u-boot>`__
+
+-  RCW:
+   `link <https://source.codeaurora.org/external/qoriq/qoriq-components/rcw>`__
+
+-  ddr-phy-binary: Required by platforms that need fip-ddr.
+   `link <https:://github.com/NXP/ddr-phy-binary>`__
+
+-  cst: Required for TBBR.
+   `link <https:://source.codeaurora.org/external/qoriq/qoriq-components/cst>`__
+
+Build Procedure
+---------------
+
+-  Fetch all the above repositories into local host.
+
+-  Prepare AARCH64 toolchain and set the environment variable "CROSS_COMPILE".
+
+   .. code:: shell
+
+       export CROSS_COMPILE=.../bin/aarch64-linux-gnu-
+
+-  Build RCW. Refer README from the respective cloned folder for more details.
+
+-  Build u-boot and OPTee firstly, and get binary images: u-boot.bin and tee.bin.
+   For u-boot you can use the <platform>_tfa_defconfig for build.
+
+-  Copy/clone the repo "ddr-phy-binary" to the tfa directory for platform needing ddr-fip.
+
+-  Below are the steps to build TF-A images for the supported platforms.
+
+Compilation steps without BL32
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+BUILD BL2:
+
+-To compile
+   .. code:: shell
+
+       make PLAT=$PLAT \
+       BOOT_MODE=<platform_supported_boot_mode> \
+       RCW=$RCW_BIN \
+       pbl
+
+BUILD FIP:
+
+   .. code:: shell
+
+       make PLAT=$PLAT \
+       BOOT_MODE=<platform_supported_boot_mode> \
+       RCW=$RCW_BIN \
+       BL33=$UBOOT_SECURE_BIN \
+       pbl \
+       fip
+
+Compilation steps with BL32
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+BUILD BL2:
+
+-To compile
+   .. code:: shell
+
+       make PLAT=$PLAT \
+       BOOT_MODE=<platform_supported_boot_mode> \
+       RCW=$RCW_BIN \
+       BL32=$TEE_BIN SPD=opteed\
+       pbl
+
+BUILD FIP:
+
+   .. code:: shell
+
+       make PLAT=$PLAT \
+       BOOT_MODE=<platform_supported_boot_mode> \
+       RCW=$RCW_BIN \
+       BL32=$TEE_BIN SPD=opteed\
+       BL33=$UBOOT_SECURE_BIN \
+       pbl \
+       fip
+
+
+BUILD fip-ddr (Mandatory for certain platforms, refer table above):
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+-To compile additional fip-ddr for selected platforms(Refer above table if the platform needs fip-ddr).
+   .. code:: shell
+
+	make PLAT=<platform_name> fip-ddr
+
+
+Deploy ATF Images
+=================
+
+Note: The size in the standard uboot commands for copy to nor, qspi, nand or sd
+should be modified based on the binary size of the image to be copied.
+
+-  Deploy ATF images on flexspi-Nor flash Alt Bank from U-Boot prompt.
+   --  Commands to flash images for bl2_xxx.pbl and fip.bin.
+
+   .. code:: shell
+
+        tftp 82000000  $path/bl2_flexspi_nor.pbl;
+        i2c mw 66 50 20;sf probe 0:0; sf erase 0 +$filesize; sf write 0x82000000 0x0 $filesize;
+
+        tftp 82000000  $path/fip.bin;
+        i2c mw 66 50 20;sf probe 0:0; sf erase 0x100000 +$filesize; sf write 0x82000000 0x100000 $filesize;
+
+   --  Next step is valid for platform where FIP-DDR is needed.
+
+   .. code:: shell
+
+        tftp 82000000  $path/ddr_fip.bin;
+        i2c mw 66 50 20;sf probe 0:0; sf erase 0x800000 +$filesize; sf write 0x82000000 0x800000 $filesize;
+
+   --  Then reset to alternate bank to boot up ATF.
+
+   .. code:: shell
+
+        qixisreset altbank;
+
+-  Deploy ATF images on SD/eMMC from U-Boot prompt.
+   -- file_size_in_block_sizeof_512 = (Size_of_bytes_tftp / 512)
+
+   .. code:: shell
+
+        mmc dev <idx>; (idx = 1 for eMMC; idx = 0 for SD)
+
+        tftp 82000000  $path/bl2_<sd>_or_<emmc>.pbl;
+        mmc write 82000000 8 <file_size_in_block_sizeof_512>;
+
+        tftp 82000000  $path/fip.bin;
+        mmc write 82000000 0x800 <file_size_in_block_sizeof_512>;
+
+    --  Next step is valid for platform that needs FIP-DDR.
+
+   .. code:: shell
+
+        tftp 82000000  $path/ddr_fip.bin;
+        mmc write 82000000 0x4000 <file_size_in_block_sizeof_512>;
+
+   --  Then reset to sd/emmc to boot up ATF from sd/emmc as boot-source.
+
+   .. code:: shell
+
+        qixisreset <sd or emmc>;
+
+Trusted Board Boot:
+===================
+
+For TBBR, the binary name changes:
+
++-------------+--------------------------+---------+-------------------+
+|  Boot Type  |           BL2            |   FIP   |      FIP-DDR      |
++=============+==========================+=========+===================+
+| Normal Boot |  bl2_<boot_mode>.pbl     | fip.bin | ddr_fip.bin       |
++-------------+--------------------------+---------+-------------------+
+| TBBR Boot   |  bl2_<boot_mode>_sec.pbl | fip.bin | ddr_fip_sec.bin   |
++-------------+--------------------------+---------+-------------------+
+
+Refer `nxp-ls-tbbr.rst`_ for detailed user steps.
+
+
+.. _lx2160ardb: https://www.nxp.com/products/processors-and-microcontrollers/arm-processors/layerscape-communication-process/layerscape-lx2160a-multicore-communications-processor:LX2160A
+.. _nxp-ls-tbbr.rst: ./nxp-ls-tbbr.rst