u-boot/board/st/stm32mp1
Patrick Delaunay 320d266368 stm32mp1: Allow to activate CONFIG_DEBUG_UART
Add the needed information to enable the debug uart
to have printf before the serial driver probe
(so before probe for clock, pincontrol and reset drivers)

To enable the debug on uart 4 (default console):
+ CONFIG_DEBUG_UART=y
+ CONFIG_DEBUG_UART_STM32=y

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
2018-05-26 18:19:18 -04:00
..
board.c stm32mp1: Allow to activate CONFIG_DEBUG_UART 2018-05-26 18:19:18 -04:00
Kconfig board: st: add generic board for STM32MP1 family 2018-03-19 16:14:22 -04:00
MAINTAINERS board: st: add generic board for STM32MP1 family 2018-03-19 16:14:22 -04:00
Makefile SPDX: Convert all of our multiple license tags to Linux Kernel style 2018-05-07 10:24:31 -04:00
README SPDX: Convert all of our multiple license tags to Linux Kernel style 2018-05-07 10:24:31 -04:00
spl.c SPDX: Convert all of our multiple license tags to Linux Kernel style 2018-05-07 10:24:31 -04:00
stm32mp1.c SPDX: Convert all of our multiple license tags to Linux Kernel style 2018-05-07 10:24:31 -04:00

SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
#
# Copyright (C) 2018 STMicroelectronics - All Rights Reserved
#

U-Boot on STMicroelectronics STM32MP1
======================================

1. Summary
==========
This is a quick instruction for setup stm32mp1 boards.

2. Supported devices
====================
U-Boot supports one STMP32MP1 SoCs: STM32MP157

The STM32MP157 is a Cortex-A MPU aimed at various applications.
It features:
- Dual core Cortex-A7 application core
- 2D/3D image composition with GPU
- Standard memories interface support
- Standard connectivity, widely inherited from the STM32 MCU family
- Comprehensive security support

Everything is supported in Linux but U-Boot is limited to:
1. UART
2. SDCard/MMC controller (SDMMC)

And the necessary drivers
1. I2C
2. STPMU1
3. Clock, Reset

Currently the following boards are supported:
+ stm32mp157c-ed1

3. Boot Sequences
=================

BootRom => FSBL in SYSRAM => SSBL in DDR => OS (Linux Kernel)

with FSBL = First Stage Bootloader
     SSBL = Second Stage Bootloader

One boot configuration is supported:

   The "Basic" boot chain (defconfig_file : stm32mp15_basic_defconfig)
   BootRom => FSBL = U-Boot SPL => SSBL = U-Boot
   SPL has limited security initialisation
   U-Boot is running in secure mode and provide a secure monitor to the kernel
   with only PSCI support (Power State Coordination Interface defined by ARM)

All the STM32MP1 board supported by U-Boot use the same generic board
stm32mp1 which support all the bootable devices.

Each board is configurated only with the associated device tree.

4. Device Tree Selection
========================

You need to select the appropriate device tree for your board,
the supported device trees for stm32mp157 are:

+ ed1: daughter board with pmic stpmu1
  dts: stm32mp157c-ed1

5. Build Procedure
==================

1. Install required tools for U-Boot

   + install package needed in U-Boot makefile
     (libssl-dev, swig, libpython-dev...)
   + install ARMv7 toolchain for 32bit Cortex-A (from Linaro,
     from SDK for STM32MP1, or any crosstoolchains from your distribution)

2. Set the cross compiler:

	# export CROSS_COMPILE=/path/to/toolchain/arm-linux-gnueabi-
	(you can use any gcc cross compiler compatible with U-Boot)

3. Select the output directory (optional)

	# export KBUILD_OUTPUT=/path/to/output

	for example: use one output directory for each configuration
	# export KBUILD_OUTPUT=stm32mp15_basic

4. Configure the U-Boot:

	# make <defconfig_file>

	- For basic boot mode: "stm32mp15_basic_defconfig"

5. Configure the device-tree and build the U-Boot image:

	# make DEVICE_TREE=<name> all


  example:
     basic boot on ed1
	# export KBUILD_OUTPUT=stm32mp15_basic
	# make stm32mp15_basic_defconfig
	# make DEVICE_TREE=stm32mp157c-ed1 all

6. Output files

  BootRom and ATF expect binaries with STM32 image header
  SPL expects file with U-Boot uImage header

  So in the output directory (selected by KBUILD_OUTPUT),
  you can found the needed files:

   + FSBL = spl/u-boot-spl.stm32
   + SSBL = u-boot.img

6. Switch Setting for Boot Mode
===============================

You can select the boot mode, on the board ed1 with the switch SW1

 -----------------------------------
  Boot Mode   BOOT2   BOOT1   BOOT0
 -----------------------------------
  Reserved	0	0	0
  NOR		0	0	1
  SD-Card	1	1	1
  SD-Card	1	0	1
  eMMC		0	1	0
  NAND		0	1	1
  Recovery	1	1	0
  Recovery	0	0	0

Recovery is a boot from serial link (UART/USB) and it is used with
STM32CubeProgrammer tool to load executable in RAM and to update the flash
devices available on the board (NOR/NAND/eMMC/SDCARD).
The communication between HOST and board is based on
- for UARTs : the uart protocol used with all MCU STM32
- for USB : based on USB DFU 1.1 (without the ST extensions used on MCU STM32)

7. Prepare an SDCard
===================

The minimal requirements for STMP32MP1 boot up to U-Boot are:
- GPT partitioning (with gdisk or with sgdisk)
- 2 fsbl partitions, named fsbl1 and fsbl2, size at least 256KiB
- one ssbl partition for U-Boot

Then the minimal GPT partition is:
   ----- ------- --------- -------------
  | Num | Name  | Size    |  Content    |
   ----- ------- -------- --------------
  |  1  | fsbl1 | 256 KiB |  ATF or SPL |
  |  2  | fsbl2 | 256 KiB |  ATF or SPL |
  |  3  | ssbl  | enought |  U-Boot     |
  |  *  |  -    |  -      |  Boot/Rootfs|
   ----- ------- --------- -------------

(*) add bootable partition for extlinux.conf
    following Generic Distribution
    (doc/README.distro for use)

  according the used card reader select the block device
  (/dev/sdx or /dev/mmcblk0)
  in the next example I use /dev/mmcblk0

for example: with gpt table with 128 entries

  a) remove previous formatting
	# sgdisk -o /dev/<SDCard dev>

  b) create minimal image
	# sgdisk --resize-table=128 -a 1 \
		-n 1:34:545		-c 1:fsbl1 \
		-n 2:546:1057		-c 2:fsbl2 \
		-n 3:1058:5153		-c 3:ssbl \
		-p /dev/<SDCard dev>

	you can add other partition for kernel (rootfs for example)

  c) copy the FSBL (2 times) and SSBL file on the correct partition.
     in this example in partition 1 to 3

     for basic boot mode : <SDCard dev> = /dev/mmcblk0
	# dd if=u-boot-spl.stm32 of=/dev/mmcblk0p1
	# dd if=u-boot-spl.stm32 of=/dev/mmcblk0p2
	# dd if=u-boot.img of=/dev/mmcblk0p3

To boot from SDCard, select BootPinMode = 1 1 1 and reset.

8. Prepare eMMC
===============
You can use U-Boot to copy binary in eMMC.

In the next example, you need to boot from SDCARD and the images (u-boot-spl.stm32, u-boot.img)
are presents on SDCARD (mmc 0) in ext4 partition 4 (bootfs).

To boot from SDCard, select BootPinMode = 1 1 1 and reset.

Then you update the eMMC with the next U-Boot command :

a) prepare GPT on eMMC,
	example with 2 partitions, bootfs and roots:

	# setenv emmc_part "name=ssbl,size=2MiB;name=bootfs,type=linux,bootable,size=64MiB;name=rootfs,type=linux,size=512"
	# gpt write mmc 1 ${emmc_part}

b) copy SPL on eMMC on firts boot partition
	(SPL max size is 256kB, with LBA 512, 0x200)

	# ext4load mmc 0:4 0xC0000000 u-boot-spl.stm32
	# mmc dev 1
	# mmc partconf 1 1 1 1
	# mmc write ${fileaddr} 0 200
	# mmc partconf 1 1 1 0

b) copy U-Boot in first GPT partition of eMMC

	# ext4load mmc 0:4 0xC0000000 u-boot.img
	# mmc dev 1
	# part start mmc 1 1 partstart
	# part size mmc 1 1 partsize
	# mmc write ${fileaddr} ${partstart} ${partsize}

To boot from eMMC, select BootPinMode = 0 1 0 and reset.