doc: spacemit: bananapi_f3: document Banana Pi F3 board

Add document for Banana Pi F3 board which based on SpacemiT's K1 SoC.

Signed-off-by: Kongyang Liu <seashell11234455@gmail.com>
Signed-off-by: Huan Zhou <pericycle.cc@gmail.com>
Tested-by: Marcel Ziswiler <marcel@ziswiler.com>
Reviewed-by: Yixun Lan <dlan@gentoo.org>

doc/board/index.rst

@@ -55,6 +55,7 @@ Board-specific doc
    sipeed/index
    socionext/index
    sophgo/index
+   spacemit/index
    st/index
    starfive/index
    ste/index

doc/board/spacemit/bananapi-f3.rst

@@ -0,0 +1,106 @@
+.. SPDX-License-Identifier: GPL-2.0-or-later
+
+Banana Pi BPI-F3
+================
+
+Building
+~~~~~~~~
+1. Install the SpacemiT riscv cross compile toolchain_, or skip it if riscv toolchain is installed.
+
+.. _toolchain: https://archive.spacemit.com/toolchain/
+
+2. Setup cross compilation environment variable:
+
+.. code-block:: console
+
+   export CROSS_COMPILE=<riscv64 toolchain prefix, e.g /opt/spacemit/bin/riscv64-unknown-linux-gnu->
+
+3. Before building U-Boot, OpenSBI should be built first. OpenSBI can be
+built for SpacemiT K1 SoC as below:
+
+.. code-block:: console
+
+   git clone https://github.com/cyyself/opensbi -b k1-opensbi
+   cd opensbi
+   make PLATFORM=generic
+
+4. Then build U-Boot as following:
+
+.. code-block:: console
+
+   cd <U-Boot-dir>
+   make bananapi-f3_defconfig
+   make OPENSBI=<OpenSBI-dir>/build/platform/generic/firmware/fw_dynamic.bin
+
+This will generate u-boot.itb
+
+Burning
+~~~~~~~
+Actually, we can replace the uboot partition of Bianbu Linux which is the bsp_ to validate this patch,
+use `balena etcher` to burn the bianbu-minimal.img to the sd card,
+and replace the /dev/sdx4 where places the uboot_ with the `u-boot.itb` generated from this patch.
+Or use fastboot:
+Collect FSBL.bin, u-boot.itb, partition_2M.json, bootinfo_spinor.bin
+u-boot-env-default.bin, fw_dynamic.itb from vendor SDK
+
+.. code-block:: console
+
+   fastboot stage FSBL.bin
+   fastboot continue
+   fastboot stage u-boot.itb-vendor # the itb from vendor uboot
+   fastboot continue
+
+   fastboot flash mtd partition_2M.json
+   fastboot flash bootinfo bootinfo_spinor.bin
+   fastboot flash fsbl FSBL.bin
+   fastboot flash env u-boot-env-default.bin
+   fastboot flash opensbi fw_dynamic.itb
+
+   fastboot flash uboot u-boot.itb-mainline # the itb from mainline uboot
+
+.. _bsp: https://archive.spacemit.com/image/k1/version/bianbu/v2.0/
+.. _uboot: https://bianbu-linux.spacemit.com/en/device/boot#21-firmware-layout
+
+Booting
+~~~~~~~
+Sample boot log from Banana Pi BPI-F3 board
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+.. code-block:: none
+
+   try sd...
+   bm:3
+   j...
+
+   U-Boot SPL 2022.10spacemit-dirty (Oct 21 2024 - 09:01:13 +0000)
+   [   0.279] DDR type LPDDR4X
+   [   0.292] lpddr4_silicon_init consume 13ms
+   [   0.293] Change DDR data rate to 2400MT/s
+   [   0.430] ## Checking hash(es) for config conf-1 ... OK
+   [   0.432] ## Checking hash(es) for Image opensbi ... OK
+   [   0.437] ## Checking hash(es) for Image uboot ... OK
+   [   0.443] ## Checking hash(es) for Image fdt-1 ... OK
+   [   0.488] ## Checking hash(es) for config config_1 ... OK
+   [   0.490] ## Checking hash(es) for Image opensbi ... crc32+ OK
+
+
+   U-Boot 2024.10-rc4-00462-g5b138cfcc587-dirty (Nov 28 2024 - 14:56:49 +0800)
+
+   DRAM:  4 GiB
+   Core:  19 devices, 8 uclasses, devicetree: separate
+   Loading Environment from nowhere... OK
+   In:    serial@d4017000
+   Out:   serial@d4017000
+   Err:   serial@d4017000
+   Net:   No ethernet found.
+   => cpu list
+   0: cpu@0      spacemit,x60
+   1: cpu@1      spacemit,x60
+   2: cpu@2      spacemit,x60
+   3: cpu@3      spacemit,x60
+   4: cpu@4      spacemit,x60
+   5: cpu@5      spacemit,x60
+   6: cpu@6      spacemit,x60
+   7: cpu@7      spacemit,x60
+   => test
+   =>
+

doc/board/spacemit/index.rst

@@ -0,0 +1,9 @@
+.. SPDX-License-Identifier: GPL-2.0-or-later
+
+SpacemiT
+========
+.. toctree::
+   :maxdepth: 1
+
+   bananapi-f3
+