Re: [PATCH] docs/system/riscv: sifive_u: Update U-Boot instructions

[Alistair Francis]

On Sun, Sep 12, 2021 at 1:34 AM Bin Meng <bmeng.cn@gmail.com> wrote:
>
> In U-Boot v2021.07 release, there were 2 major changes for the
> SiFive Unleashed board support:
>
> - Board config name was changed from sifive_fu540_defconfig to
>   sifive_unleashed_defconfig
> - The generic binman tool was used to generate the FIT image
>   (combination of U-Boot proper, DTB and OpenSBI firmware)
>
> which make the existing U-Boot instructions out of date.
>
> Update the doc with latest instructions.
>
> Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>
>  docs/system/riscv/sifive_u.rst | 49 ++++++++++++++++++----------------
>  1 file changed, 26 insertions(+), 23 deletions(-)
>
> diff --git a/docs/system/riscv/sifive_u.rst b/docs/system/riscv/sifive_u.rst
> index 01108b5ecc..8ac93d0153 100644
> --- a/docs/system/riscv/sifive_u.rst
> +++ b/docs/system/riscv/sifive_u.rst
> @@ -209,15 +209,16 @@ command line options with ``qemu-system-riscv32``.
>  Running U-Boot
>  --------------
>
> -U-Boot mainline v2021.01 release is tested at the time of writing. To build a
> +U-Boot mainline v2021.07 release is tested at the time of writing. To build a
>  U-Boot mainline bootloader that can be booted by the ``sifive_u`` machine, 
> use
> -the sifive_fu540_defconfig with similar commands as described above for 
> Linux:
> +the sifive_unleashed_defconfig with similar commands as described above for
> +Linux:
>
>  .. code-block:: bash
>
>    $ export CROSS_COMPILE=riscv64-linux-
>    $ export OPENSBI=/path/to/opensbi-riscv64-generic-fw_dynamic.bin
> -  $ make sifive_fu540_defconfig
> +  $ make sifive_unleashed_defconfig
>
>  You will get spl/u-boot-spl.bin and u-boot.itb file in the build tree.
>
> @@ -312,31 +313,29 @@ board on QEMU ``sifive_u`` machine out of the box. This 
> allows users to
>  develop and test the recommended RISC-V boot flow with a real world use
>  case: ZSBL (in QEMU) loads U-Boot SPL from SD card or SPI flash to L2LIM,
>  then U-Boot SPL loads the combined payload image of OpenSBI fw_dynamic
> -firmware and U-Boot proper. However sometimes we want to have a quick test
> -of booting U-Boot on QEMU without the needs of preparing the SPI flash or
> -SD card images, an alternate way can be used, which is to create a U-Boot
> -S-mode image by modifying the configuration of U-Boot:
> +firmware and U-Boot proper.
> +
> +However sometimes we want to have a quick test of booting U-Boot on QEMU
> +without the needs of preparing the SPI flash or SD card images, an alternate
> +way can be used, which is to create a U-Boot S-mode image by modifying the
> +configuration of U-Boot:
>
>  .. code-block:: bash
>
> +  $ export CROSS_COMPILE=riscv64-linux-
> +  $ make sifive_unleashed_defconfig
>    $ make menuconfig
>
> -then manually select the following configuration in U-Boot:
> -
> -  Device Tree Control > Provider of DTB for DT Control > Prior Stage 
> bootloader DTB
> +then manually select the following configuration:
>
> -This lets U-Boot to use the QEMU generated device tree blob. During the 
> build,
> -a build error will be seen below:
> +  * Device Tree Control ---> Provider of DTB for DT Control ---> Prior Stage 
> bootloader DTB
>
> -.. code-block:: none
> +and unselect the following configuration:
>
> -  MKIMAGE u-boot.img
> -  ./tools/mkimage: Can't open arch/riscv/dts/hifive-unleashed-a00.dtb: No 
> such file or directory
> -  ./tools/mkimage: failed to build FIT
> -  make: *** [Makefile:1440: u-boot.img] Error 1
> +  * Library routines ---> Allow access to binman information in the device 
> tree
>
> -The above errors can be safely ignored as we don't run U-Boot SPL under QEMU
> -in this alternate configuration.
> +This changes U-Boot to use the QEMU generated device tree blob, and bypass
> +running the U-Boot SPL stage.
>
>  Boot the 64-bit U-Boot S-mode image directly:
>
> @@ -351,14 +350,18 @@ It's possible to create a 32-bit U-Boot S-mode image as 
> well.
>  .. code-block:: bash
>
>    $ export CROSS_COMPILE=riscv64-linux-
> -  $ make sifive_fu540_defconfig
> +  $ make sifive_unleashed_defconfig
>    $ make menuconfig
>
>  then manually update the following configuration in U-Boot:
>
> -  Device Tree Control > Provider of DTB for DT Control > Prior Stage 
> bootloader DTB
> -  RISC-V architecture > Base ISA > RV32I
> -  Boot images > Text Base > 0x80400000
> +  * Device Tree Control ---> Provider of DTB for DT Control ---> Prior Stage 
> bootloader DTB
> +  * RISC-V architecture ---> Base ISA ---> RV32I
> +  * Boot options ---> Boot images ---> Text Base ---> 0x80400000
> +
> +and unselect the following configuration:
> +
> +  * Library routines ---> Allow access to binman information in the device 
> tree
>
>  Use the same command line options to boot the 32-bit U-Boot S-mode image:
>
> --
> 2.25.1
>
>