Re: [PATCH 5/5] Documentation: boards: add initial STM32MP documentation

[Roland Hieber <rhi@pengutronix.de>]

On Fri, Jul 12, 2019 at 12:24:57PM +0200, Ahmad Fatoum wrote:
> Support for the SoC is still in progress, but lets document
> what we have now.
> 
> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> ---
>  Documentation/boards/stm32mp.rst | 73 ++++++++++++++++++++++++++++++++
>  1 file changed, 73 insertions(+)
>  create mode 100644 Documentation/boards/stm32mp.rst
> 
> diff --git a/Documentation/boards/stm32mp.rst b/Documentation/boards/stm32mp.rst
> new file mode 100644
> index 000000000000..7f787bac203e
> --- /dev/null
> +++ b/Documentation/boards/stm32mp.rst
> @@ -0,0 +1,73 @@
> +STMicroelectronics STM32MP
> +==========================
> +
> +.. note::
> +
> +  Support for the STM32MP architecure in barebox is still in progress.
> +  Bootstrapping an OS from mainline barebox is not yet supported.
> +
> +The STM32MP is a line of 32-bit ARM SoCs. They reuse peripherals of the
> +STM32 line of microcontrollers and can have a STM32 MCU embedded as co-processor
> +as well.
> +
> +The boot process of the STM32MP SoC is a two step process.
> +The first stage boot loader (FSBL) is loaded by the ROM code into the built-in
> +SYSRAM and executed. The FSBL sets up the SDRAM, install a secure monitor and

Small typo here, s/install/installs/.

> +then the second stage boot loader (SSBL) is loaded into DRAM.
> +
> +When building barebox, the resulting ``barebox-${board}.img`` file has the STM32
> +header preprended, so it can be loaded directly as FSBL by the ARM TF-A
> +(https://github.com/ARM-software/arm-trusted-firmware). Each entry point has a
> +header-less image ending in ``*.pblb`` as well.
> +
> +Use of barebox as FSBL is not supported.
> +
> +Following boards are currently supported in barebox:
> +

None? :-)

 - Roland

> +Building barebox
> +----------------
> +
> +With multi-image and device trees, it's expected to have ``stm32mp_defconfig``
> +as sole defconfig for all STM32MP boards::
> +
> +  make ARCH=arm stm32mp_defconfig
> +
> +The resulting images will be placed under ``images/``:
> +
> +::
> +
> +  barebox-stm32mp157c-dk2.img
> +
> +
> +Flashing barebox
> +----------------
> +
> +An appropriate image for the boot media can be generated with following
> +``genimage(1)`` config::
> +
> +  image @STM32MP_BOARD@.img {
> +      hdimage {
> +          align = 1M
> +          gpt = "true"
> +      }
> +      partition fsbl1 {
> +          image = "tf-a-@STM32MP_BOARD@.stm32"
> +          size = 256K
> +      }
> +      partition fsbl2 {
> +          image = "tf-a-@STM32MP_BOARD@.stm32"
> +          size = 256K
> +      }
> +      partition ssbl {
> +          image = "barebox-@STM32MP_BOARD@.img"
> +          size = 1M
> +      }
> +  }
> +
> +Image can then be flashed on e.g. a SD-Card.
> +
> +TODO
> +----
> +
> +* Extend barebox MMCI support to support the SDMMC2
> +* Extend barebox DesignWare MAC support to support the stmmac
> -- 
> 2.20.1
> 
> 
> _______________________________________________
> barebox mailing list
> barebox@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/barebox
> 

-- 
Roland Hieber                     | r.hieber@pengutronix.de     |
Pengutronix e.K.                  | https://www.pengutronix.de/ |
Peiner Str. 6-8, 31137 Hildesheim | Phone: +49-5121-206917-5086 |
Amtsgericht Hildesheim, HRA 2686  | Fax:   +49-5121-206917-5555 |

_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox