doc: Move documents into subdirectories

This change creates the following directories under docs/
in order to provide a grouping for the content:

- components
- design
- getting_started
- perf
- process

In each of these directories an index.rst file is created
and this serves as an index / landing page for each of the
groups when the pages are compiled. Proper layout of the
top-level table of contents relies on this directory/index
structure.

Without this patch it is possible to build the documents
correctly with Sphinx but the output looks messy because
there is no overall hierarchy.

Change-Id: I3c9f4443ec98571a56a6edf775f2c8d74d7f429f
Signed-off-by: Paul Beesley <paul.beesley@arm.com>

9 files changed, 532 insertions, 2 deletions

diff --git a/docs/plat/index.rst b/docs/plat/index.rst
new file mode 100644
index 00000000..3a917f36
--- /dev/null
+++ b/docs/plat/index.rst
@@ -0,0 +1,29 @@
+Platform Ports
+==============
+
+.. toctree::
+   :maxdepth: 1
+   :caption: Contents
+   :numbered:
+
+   allwinner
+   fvp_ve
+   imx8
+   imx8m
+   intel-stratix10
+   ls1043a
+   meson-gxbb
+   meson-gxl
+   mt8183
+   nvidia-tegra
+   poplar
+   qemu
+   rcar-gen3
+   rockchip
+   rpi3
+   socionext-uniphier
+   stm32mp1
+   synquacer
+   ti-k3
+   warp7
+   xilinx-zynqmp
diff --git a/docs/plat/marvell/build.txt b/docs/plat/marvell/build.txt
new file mode 100644
index 00000000..7b75196f
--- /dev/null
+++ b/docs/plat/marvell/build.txt
@@ -0,0 +1,194 @@
+TF-A Build Instructions
+======================
+
+This section describes how to compile the ARM Trusted Firmware (TF-A) project for Marvell's platforms.
+
+Build Instructions
+------------------
+(1) Set the cross compiler::
+
+		> export CROSS_COMPILE=/path/to/toolchain/aarch64-linux-gnu-
+
+(2) Set path for FIP images:
+
+	Set U-Boot image path (relatively to TF-A root or absolute path)::
+
+		> export BL33=path/to/u-boot.bin
+
+	For example: if U-Boot project (and its images) is located at ~/project/u-boot,
+	BL33 should be ~/project/u-boot/u-boot.bin
+
+	.. note::
+
+	   u-boot.bin should be used and not u-boot-spl.bin
+
+	Set MSS/SCP image path (mandatory only for Armada80x0)::
+
+		> export SCP_BL2=path/to/mrvl_scp_bl2*.img
+
+(3) Armada-37x0 build requires WTP tools installation.
+
+	See below in the section "Tools and external components installation".
+	Install ARM 32-bit cross compiler, which is required for building WTMI image for CM3::
+
+		> sudo apt-get install gcc-arm-linux-gnueabi
+
+(4) Clean previous build residuals (if any)::
+
+		> make distclean
+
+(5) Build TF-A:
+
+	There are several build options:
+
+	- DEBUG: default is without debug information (=0). in order to enable it use DEBUG=1
+		Must be disabled when building UART recovery images due to current console driver
+		implementation that is not compatible with Xmodem protocol used for boot image download.
+
+	- LOG_LEVEL: defines the level of logging which will be purged to the default output port.
+
+		LOG_LEVEL_NONE		0
+		LOG_LEVEL_ERROR		10
+		LOG_LEVEL_NOTICE	20
+		LOG_LEVEL_WARNING	30
+		LOG_LEVEL_INFO		40
+		LOG_LEVEL_VERBOSE	50
+
+	- USE_COHERENT_MEM: This flag determines whether to include the coherent memory region in the
+		BL memory map or not.
+
+	- LLC_ENABLE: Flag defining the LLC (L3) cache state. The cache is enabled by default (LLC_ENABLE=1).
+
+	- MARVELL_SECURE_BOOT: build trusted(=1)/non trusted(=0) image, default is non trusted.
+
+	- BLE_PATH:
+		Points to BLE (Binary ROM extension) sources folder. Only required for A8K builds.
+		The parameter is optional, its default value is "plat/marvell/a8k/common/ble".
+
+	- MV_DDR_PATH:
+		For A7/8K, use this parameter to point to mv_ddr driver sources to allow BLE build. For A37x0,
+		it is used for ddr_tool build.
+		Usage example: MV_DDR_PATH=path/to/mv_ddr
+		The parameter is optional for A7/8K, when this parameter is not set, the mv_ddr
+		sources are expected to be located at: drivers/marvell/mv_ddr. However, the parameter
+		is necessary for A37x0.
+		For the mv_ddr source location, check the section "Tools and external components installation"
+
+	- DDR_TOPOLOGY: For Armada37x0 only, the DDR topology map index/name, default is 0.
+		Supported Options:
+			- DDR3 1CS (0): DB-88F3720-DDR3-Modular (512MB); EspressoBIN (512MB)
+			- DDR4 1CS (1): DB-88F3720-DDR4-Modular (512MB)
+			- DDR3 2CS (2): EspressoBIN V3-V5 (1GB)
+			- DDR4 2CS (3): DB-88F3720-DDR4-Modular (4GB)
+			- DDR3 1CS (4): DB-88F3720-DDR3-Modular (1GB)
+			- DDR4 1CS (5): EspressoBin V7 (1GB)
+			- DDR4 2CS (6): EspressoBin V7 (2GB)
+			- CUSTOMER (CUST): Customer board, DDR3 1CS 512MB
+
+	- CLOCKSPRESET: For Armada37x0 only, the clock tree configuration preset including CPU and DDR frequency,
+		default is CPU_800_DDR_800.
+			- CPU_600_DDR_600	-	CPU at 600 MHz, DDR at 600 MHz
+			- CPU_800_DDR_800	-	CPU at 800 MHz, DDR at 800 MHz
+			- CPU_1000_DDR_800	-	CPU at 1000 MHz, DDR at 800 MHz
+			- CPU_1200_DDR_750	-	CPU at 1200 MHz, DDR at 750 MHz
+
+	- BOOTDEV: For Armada37x0 only, the flash boot device, default is SPINOR,
+		Currently, Armada37x0 only supports SPINOR, SPINAND, EMMCNORM and SATA:
+
+			- SPINOR - SPI NOR flash boot
+			- SPINAND - SPI NAND flash boot
+			- EMMCNORM - eMMC Download Mode
+				Download boot loader or program code from eMMC flash into CM3 or CA53
+				Requires full initialization and command sequence
+			- SATA - SATA device boot
+
+	- PARTNUM: For Armada37x0 only, the boot partition number, default is 0. To boot from eMMC, the value
+		should be aligned with the parameter in U-Boot with name of CONFIG_SYS_MMC_ENV_PART, whose
+		value by default is 1.
+		For details about CONFIG_SYS_MMC_ENV_PART, please refer to the U-Boot build instructions.
+
+	- WTMI_IMG: For Armada37x0 only, the path of the WTMI image can point to an image which does
+		nothing, an image which supports EFUSE or a customized CM3 firmware binary. The default image
+		is wtmi.bin that built from sources in WTP folder, which is the next option. If the default
+		image is OK, then this option should be skipped.
+
+	- WTP: For Armada37x0 only, use this parameter to point to wtptools source code directory, which
+		can be found as a3700_utils.zip in the release.
+		Usage example: WTP=/path/to/a3700_utils
+
+	For example, in order to build the image in debug mode with log level up to 'notice' level run::
+
+		> make DEBUG=1 USE_COHERENT_MEM=0 LOG_LEVEL=20 PLAT=<MARVELL_PLATFORM> all fip
+
+	And if we want to build a Armada37x0 image in debug mode with log level up to 'notice' level,
+	the image has the preset CPU at 1000 MHz, preset DDR3 at 800 MHz, the DDR topology of DDR4 2CS,
+	the image boot from SPI NOR flash partition 0, and the image is non trusted in WTP, the command
+	line is as following::
+
+		> make DEBUG=1 USE_COHERENT_MEM=0 LOG_LEVEL=20 CLOCKSPRESET=CPU_1000_DDR_800 \
+			MARVELL_SECURE_BOOT=0 DDR_TOPOLOGY=3 BOOTDEV=SPINOR PARTNUM=0 PLAT=a3700 all fip
+
+	Supported MARVELL_PLATFORM are:
+		- a3700 (for both A3720 DB and EspressoBin)
+		- a70x0
+		- a70x0_amc (for AMC board)
+		- a80x0
+		- a80x0_mcbin (for MacciatoBin)
+
+Special Build Flags
+--------------------
+	- PLAT_RECOVERY_IMAGE_ENABLE: When set this option to enable secondary recovery function when build
+		atf. In order to build UART recovery image this operation should be disabled for a70x0 and a80x0
+		because of hardware limitation (boot from secondary image can interrupt UART recovery process).
+		This MACRO definition is set in plat/marvell/a8k/common/include/platform_def.h file
+
+(for more information about build options, please refer to section 'Summary of build options' in  TF-A user-guide:
+ https://github.com/ARM-software/arm-trusted-firmware/blob/master/docs/user-guide.md)
+
+
+Build output
+-------------
+Marvell's TF-A compilation generates 7 files:
+	- ble.bin		- BLe image
+	- bl1.bin		- BL1 image
+	- bl2.bin		- BL2 image
+	- bl31.bin		- BL31 image
+	- fip.bin		- FIP image (contains BL2, BL31 & BL33 (U-Boot) images)
+	- boot-image.bin	- TF-A image (contains BL1 and FIP images)
+	- flash-image.bin	- Image which contains boot-image.bin and SPL image;
+				  should be placed on the boot flash/device.
+
+
+Tools and external components installation
+==========================================
+
+Armada37x0 Builds require installation of 3 components
+-------------------------------------------------------
+
+(1) ARM cross compiler capable of building images for the service CPU (CM3).
+    This component is usually included in the Linux host packages.
+    On Debian/Ubuntu hosts the default GNU ARM tool chain can be installed
+    using the following command::
+
+		> sudo apt-get install gcc-arm-linux-gnueabi
+
+    Only if required, the default tool chain prefix "arm-linux-gnueabi-" can be
+    overwritten using the environment variable CROSS_CM3.
+    Example for BASH shell::
+
+		> export CROSS_CM3=/opt/arm-cross/bin/arm-linux-gnueabi
+
+(2) DDR initialization library sources (mv_ddr) available at the following repository
+    (use the "mv_ddr-armada-atf-mainline" branch)::
+    https://github.com/MarvellEmbeddedProcessors/mv-ddr-marvell.git
+
+(3) Armada3700 tools available at the following repository (use the latest release branch)::
+    https://github.com/MarvellEmbeddedProcessors/A3700-utils-marvell.git
+
+Armada70x0 and Armada80x0 Builds require installation of an additional component
+--------------------------------------------------------------------------------
+
+(1) DDR initialization library sources (mv_ddr) available at the following repository
+    (use the "mv_ddr-armada-atf-mainline" branch)::
+    https://github.com/MarvellEmbeddedProcessors/mv-ddr-marvell.git
+
diff --git a/docs/plat/marvell/misc/mvebu-a8k-addr-map.txt b/docs/plat/marvell/misc/mvebu-a8k-addr-map.txt
new file mode 100644
index 00000000..586e8b73
--- /dev/null
+++ b/docs/plat/marvell/misc/mvebu-a8k-addr-map.txt
@@ -0,0 +1,47 @@
+Address decoding flow and address translation units of Marvell Armada 8K SoC family
+
++--------------------------------------------------------------------------------------------------+
+|                                                              +-------------+    +--------------+ |
+|                                                              | Memory      +-----   DRAM CS    | |
+|+------------+ +-----------+ +-----------+                    | Controller  |    +--------------+ |
+||  AP DMA    | |           | |           |                    +-------------+                     |
+||  SD/eMMC   | | CA72 CPUs | |  AP MSS   |                    +-------------+                     |
+||  MCI-0/1   | |           | |           |                    | Memory      |                     |
+|+------+-----+ +--+--------+ +--------+--+  +------------+    | Controller  |     +-------------+ |
+|       |          |                   |     |            +----- Translaton  |     |AP           | |
+|       |          |                   |     |            |    +-------------+     |Configuration| |
+|       |          |                   +-----+            +-------------------------Space        | |
+|       |          | +-------------+         |  CCU       |                        +-------------+ |
+|       |          | | MMU         +---------+  Windows   |   +-----------+        +-------------+ |
+|       |          +-| translation |         |  Lookup    +----           +---------   AP SPI    | |
+|       |            +-------------+         |            |   |           |        +-------------+ |
+|       |            +-------------+         |            |   |  IO       |        +-------------+ |
+|       +------------| SMMU        +---------+            |   |  Windows  +---------  AP MCI0/1  | |
+|                    | translation |         +------------+   |  Lookup   |        +-------------+ |
+|                    +---------+---+                          |           |        +-------------+ |
+|             -                |                              |           +---------   AP STM    | |
+|             +-----------------                              |           |        +-------------+ |
+| AP          |                |                              +-+---------+                        |
++---------------------------------------------------------------|----------------------------------+
++-------------|-------------------------------------------------|----------------------------------+
+| CP          |            +-------------+               +------+-----+      +-------------------+ |
+|             |            |             |               |            +-------   SB CFG Space    | |
+|             |            |   DIOB      |               |            |      +-------------------+ |
+|             |            |   Windows   -----------------  IOB       |      +-------------------+ |
+|             |            |   Control   |               |  Windows   +------| SB PCIe-0 - PCIe2 | |
+|             |            |             |               |  Lookup    |      +-------------------+ |
+|             |            +------+------+               |            |      +-------------------+ |
+|             |                   |                      |            +------+      SB NAND      | |
+|             |                   |                      +------+-----+      +-------------------+ |
+|             |                   |                             |                                  |
+|             |                   |                             |                                  |
+|   +------------------+   +------------+                +------+-----+      +-------------------+ |
+|   | Network Engine   |   |            |                |            +-------  SB SPI-0/SPI-1   | |
+|   | Security Engine  |   | PCIe, MSS  |                |  RUNIT     |      +-------------------+ |
+|   | SATA, USB        |   | DMA        |                |  Windows   |      +-------------------+ |
+|   | SD/eMMC          |   |            |                |  Lookup    +-------   SB Device Bus   | |
+|   | TDM, I2C         |   |            |                |            |      +-------------------+ |
+|   +------------------+   +------------+                +------------+                            |
+|                                                                                                  |
++--------------------------------------------------------------------------------------------------+
+
diff --git a/docs/plat/marvell/misc/mvebu-amb.txt b/docs/plat/marvell/misc/mvebu-amb.txt
new file mode 100644
index 00000000..2a7a41ec
--- /dev/null
+++ b/docs/plat/marvell/misc/mvebu-amb.txt
@@ -0,0 +1,45 @@
+AMB - AXI MBUS address decoding
+-------------------------------
+
+AXI to M-bridge decoding unit driver for Marvell Armada 8K and 8K+ SoCs.
+
+- The Runit offers a second level of address windows lookup. It is used to map transaction towards
+the CD BootROM, SPI0, SPI1 and Device bus (NOR).
+- The Runit contains eight configurable windows. Each window defines a contiguous,
+address space and the properties associated with that address space.
+
+Unit		Bank		ATTR
+Device-Bus	DEV_BOOT_CS 	0x2F
+		DEV_CS0     	0x3E
+		DEV_CS1     	0x3D
+		DEV_CS2     	0x3B
+		DEV_CS3     	0x37
+SPI-0		SPI_A_CS0 	0x1E
+		SPI_A_CS1 	0x5E
+		SPI_A_CS2 	0x9E
+		SPI_A_CS3 	0xDE
+		SPI_A_CS4 	0x1F
+		SPI_A_CS5 	0x5F
+		SPI_A_CS6 	0x9F
+		SPI_A_CS7 	0xDF
+SPI1		SPI_B_CS0 	0x1A
+		SPI_B_CS1 	0x5A
+		SPI_B_CS2	0x9A
+		SPI_B_CS3	0xDA
+BOOT_ROM	BOOT_ROM	0x1D
+UART		UART		0x01
+
+Mandatory functions:
+	- marvell_get_amb_memory_map
+		returns the AMB windows configuration and the number of windows
+
+Mandatory structures:
+	amb_memory_map - Array that include the configuration of the windows
+	  every window/entry is a struct which has 2 parameters:
+	  - base address of the window
+	  - Attribute of the window
+
+Examples:
+	struct addr_map_win amb_memory_map[] = {
+		{0xf900,	AMB_DEV_CS0_ID},
+	};
diff --git a/docs/plat/marvell/misc/mvebu-ccu.txt b/docs/plat/marvell/misc/mvebu-ccu.txt
new file mode 100644
index 00000000..97640276
--- /dev/null
+++ b/docs/plat/marvell/misc/mvebu-ccu.txt
@@ -0,0 +1,23 @@
+Marvell CCU address decoding bindings
+=====================================
+
+CCU configration driver (1st stage address translation) for Marvell Armada 8K and 8K+ SoCs.
+
+The CCU node includes a description of the address decoding configuration.
+
+Mandatory functions:
+	- marvell_get_ccu_memory_map
+		return the CCU windows configuration and the number of windows
+		of the specific AP.
+
+Mandatory structures:
+	ccu_memory_map - Array that includes the configuration of the windows
+	  every window/entry is a struct which has 3 parameters:
+	  - Base address of the window
+	  - Size of the window
+	  - Target-ID of the window
+
+Example:
+	struct addr_map_win ccu_memory_map[] = {
+		{0x00000000f2000000,     0x00000000e000000,      IO_0_TID}, /* IO window */
+	};
diff --git a/docs/plat/marvell/misc/mvebu-io-win.txt b/docs/plat/marvell/misc/mvebu-io-win.txt
new file mode 100644
index 00000000..c83ad1fd
--- /dev/null
+++ b/docs/plat/marvell/misc/mvebu-io-win.txt
@@ -0,0 +1,35 @@
+Marvell IO WIN address decoding bindings
+=====================================
+
+IO Window configration driver (2nd stage address translation) for Marvell Armada 8K and 8K+ SoCs.
+
+The IO WIN includes a description of the address decoding configuration.
+
+Transactions that are decoded by CCU windows as IO peripheral, have an additional
+layer of decoding. This additional address decoding layer defines one of the
+following targets:
+	0x0 = BootRom
+	0x1 = STM (Serial Trace Macro-cell, a programmer's port into trace stream)
+	0x2 = SPI direct access
+	0x3 = PCIe registers
+	0x4 = MCI Port
+	0x5 = PCIe port
+
+Mandatory functions:
+	- marvell_get_io_win_memory_map
+		returns the IO windows configuration and the number of windows
+		of the specific AP.
+
+Mandatory structures:
+	io_win_memory_map - Array that include the configuration of the windows
+	  every window/entry is a struct which has 3 parameters:
+	  - Base address of the window
+	  - Size of the window
+	  - Target-ID of the window
+
+Example:
+	struct addr_map_win io_win_memory_map[] = {
+		{0x00000000fe000000,	0x000000001f00000,	PCIE_PORT_TID}, /* PCIe window 31Mb for PCIe port*/
+		{0x00000000ffe00000,	0x000000000100000,	PCIE_REGS_TID}, /* PCI-REG window 64Kb for PCIe-reg*/
+		{0x00000000f6000000,	0x000000000100000,	MCIPHY_TID},	/* MCI window  1Mb for PHY-reg*/
+	};
diff --git a/docs/plat/marvell/misc/mvebu-iob.txt b/docs/plat/marvell/misc/mvebu-iob.txt
new file mode 100644
index 00000000..97ec09d0
--- /dev/null
+++ b/docs/plat/marvell/misc/mvebu-iob.txt
@@ -0,0 +1,40 @@
+Marvell IOB address decoding bindings
+=====================================
+
+IO bridge configration driver (3rd stage address translation) for Marvell Armada 8K and 8K+ SoCs.
+
+The IOB includes a description of the address decoding configuration.
+
+IOB supports up to n (in CP110 n=24) windows for external memory transaction.
+When a transaction passes through the IOB, its address is compared to each of
+the enabled windows. If there is a hit and it passes the security checks, it is
+advanced to the target port.
+
+Mandatory functions:
+	- marvell_get_iob_memory_map
+		returns the IOB windows configuration and the number of windows
+
+Mandatory structures:
+	iob_memory_map - Array that include the configuration of the windows
+	  every window/entry is a struct which has 3 parameters:
+	  - Base address of the window
+	  - Size of the window
+	  - Target-ID of the window
+
+Target ID options:
+	- 0x0 = Internal configuration space
+	- 0x1 = MCI0
+	- 0x2 = PEX1_X1
+	- 0x3 = PEX2_X1
+	- 0x4 = PEX0_X4
+	- 0x5 = NAND flash
+	- 0x6 = RUNIT (NOR/SPI/BootRoom)
+	- 0x7 = MCI1
+
+Example:
+	struct addr_map_win iob_memory_map[] = {
+		{0x00000000f7000000,	0x0000000001000000,	PEX1_TID}, /* PEX1_X1 window */
+		{0x00000000f8000000,	0x0000000001000000,	PEX2_TID}, /* PEX2_X1 window */
+		{0x00000000f6000000,	0x0000000001000000,	PEX0_TID}, /* PEX0_X4 window */
+		{0x00000000f9000000,	0x0000000001000000,	NAND_TID}  /* NAND window */
+	};
diff --git a/docs/plat/marvell/porting.txt b/docs/plat/marvell/porting.txt
new file mode 100644
index 00000000..f9a39a05
--- /dev/null
+++ b/docs/plat/marvell/porting.txt
@@ -0,0 +1,118 @@
+.. _porting:
+
+TF-A Porting Guide
+=================
+
+This section describes how to port TF-A to a customer board, assuming that the SoC being used is already supported
+in TF-A.
+
+
+Source Code Structure
+---------------------
+- The customer platform specific code shall reside under "plat/marvell/<soc family>/<soc>_cust"
+	(e.g. 'plat/marvell/a8k/a7040_cust').
+- The platform name for build purposes is called "<soc>_cust" (e.g. a7040_cust).
+- The build system will reuse all files from within the soc directory, and take only the porting
+  files from the customer platform directory.
+
+Files that require porting are located at "plat/marvell/<soc family>/<soc>_cust" directory.
+
+
+Armada-70x0/Armada-80x0 Porting
+-------------------------------
+
+  - SoC Physical Address Map (marvell_plat_config.c):
+	- This file describes the SoC physical memory mapping to be used for the CCU, IOWIN, AXI-MBUS and IOB
+	  address decode units (Refer to the functional spec for more details).
+	- In most cases, using the default address decode windows should work OK.
+	- In cases where a special physical address map is needed (e.g. Special size for PCIe MEM windows,
+	  large memory mapped SPI flash...), then porting of the SoC memory map is required.
+	- Note: For a detailed information on how CCU, IOWIN, AXI-MBUS & IOB work, please refer to the SoC functional spec,
+	  and under "docs/marvell/misc/mvebu-[ccu/iob/amb/io-win].txt" files.
+
+  - boot loader recovery (marvell_plat_config.c):
+	- Background:
+		boot rom can skip the current image and choose to boot from next position if a specific value
+		(0xDEADB002) is returned by the ble main function. This feature is used for boot loader recovery
+		by booting from a valid flash-image saved in next position on flash (e.g. address 2M in SPI flash).
+
+		Supported options to implement the skip request are:
+			- GPIO
+			- I2C
+			- User defined
+
+	- Porting:
+		Under marvell_plat_config.c, implement struct skip_image that includes specific board parameters.
+		.. warning:: to disable this feature make sure the struct skip_image is not implemented.
+
+	- Example:
+		In A7040-DB specific implementation (plat/marvell/a8k/a70x0/board/marvell_plat_config.c),
+		the image skip is implemented using GPIO: mpp 33 (SW5).
+
+		Before resetting the board make sure there is a valid image on the next flash address:
+			-tftp [valid address] flash-image.bin
+			-sf update [valid address] 0x2000000 [size]
+
+		Press reset and keep pressing the button connected to the chosen GPIO pin. A skip image request
+		message is printed on the screen and boot rom boots from the saved image at the next position.
+
+  - DDR Porting (dram_port.c):
+	- This file defines the dram topology and parameters of the target board.
+	- The DDR code is part of the BLE component, which is an extension of ARM Trusted Firmware (TF-A).
+	- The DDR driver called mv_ddr is released separately apart from TF-A sources.
+	- The BLE and consequently, the DDR init code is executed at the early stage of the boot process.
+	- Each supported platform of the TF-A has its own DDR porting file called dram_port.c located at
+	  ``atf/plat/marvell/a8k/<platform>/board`` directory.
+	- Please refer to '<path_to_mv_ddr_sources>/doc/porting_guide.txt' for detailed porting description.
+	- The build target directory is "build/<platform>/release/ble".
+
+  - Comphy Porting (phy-porting-layer.h or phy-default-porting-layer.h)
+	- Background:
+		Some of the comphy's parameters value depend on the HW connection between the SoC and the PHY. Every
+		board type has specific HW characteristics like wire length. Due to those differences some comphy
+		parameters vary between board types. Therefore each board type can have its own list of values for
+		all relevant comphy parameters. The PHY porting layer specifies which parameters need to be suited and
+		the board designer should provide relevant values.
+
+		.. seealso::
+			For XFI/SFI comphy type there is procedure "rx_training" which eases process of suiting some of
+			the parameters. Please see :ref:`uboot_cmd` section: rx_training.
+
+		The PHY porting layer simplifies updating static values per board type, which are now grouped in one place.
+
+		.. note::
+			The parameters for the same type of comphy may vary even for the same board type, it is because
+			the lanes from comphy-x to some PHY may have different HW characteristic than lanes from
+			comphy-y to the same (multiplexed) or other PHY.
+
+	- Porting:
+		The porting layer for PHY was introduced in TF-A. There is one file
+		``drivers/marvell/comphy/phy-default-porting-layer.h`` which contains the defaults. Those default
+		parameters are used only if there is no appropriate phy-porting-layer.h file under:
+		``plat/marvell/<soc family>/<platform>/board/phy-porting-layer.h``. If the phy-porting-layer.h exists,
+		the phy-default-porting-layer.h is not going to be included.
+
+		.. warning::
+			Not all comphy types are already reworked to support the PHY porting layer, currently the porting
+			layer is supported for XFI/SFI and SATA comphy types.
+
+		The easiest way to prepare the PHY porting layer for custom board is to copy existing example to a new
+		platform:
+
+		- cp ``plat/marvell/a8k/a80x0/board/phy-porting-layer.h`` "plat/marvell/<soc family>/<platform>/board/phy-porting-layer.h"
+		- adjust relevant parameters or
+		- if different comphy index is used for specific feature, move it to proper table entry and then adjust.
+
+		.. note::
+			The final table size with comphy parameters can be different, depending on the CP module count for
+			given SoC type.
+
+	- Example:
+		Example porting layer for armada-8040-db is under: ``plat/marvell/a8k/a80x0/board/phy-porting-layer.h``
+
+		.. note::
+			If there is no PHY porting layer for new platform (missing phy-porting-layer.h), the default
+			values are used (drivers/marvell/comphy/phy-default-porting-layer.h) and the user is warned:
+
+		.. warning::
+			"Using default comphy parameters - it may be required to suit them for your board".
diff --git a/docs/plat/rpi3.rst b/docs/plat/rpi3.rst
index a22bfc6a..122b1de6 100644
--- a/docs/plat/rpi3.rst
+++ b/docs/plat/rpi3.rst
@@ -1,8 +1,7 @@
 Trusted Firmware-A for Raspberry Pi 3
 =====================================
 
-.. section-numbering::
-    :suffix: .
+
 
 .. contents::