boards/riscv: Add support for PINE64 Ox64 BL808 SBC

This PR adds support for PINE64 Ox64 64-bit RISC-V SBC, based on Bouffalo Lab BL808 SoC (T-Head C906 Core). Most of the code is derived from NuttX for Star64 JH7110. The source files are explained in the articles here: https://github.com/lupyuen/nuttx-ox64

### Modified Files

`boards/Kconfig`: Added Ox64 board

### New Files in boards/risc-v/bl808/ox64

`src/bl808_appinit.c`: Startup Code

`include/board.h`: Ox64 Definitions

`include/board_memorymap.h`: Memory Map

`src/etc/init.d/rc.sysinit`, `rcS`: Startup Script

`src/.gitignore`: Ignore the tmp filesystem

`scripts/ld.script`: Linker Script

`scripts/Make.defs`: Ox64 Makefile

`src/Makefile`: Ox64 Makefile

`Kconfig`: Ox64 Config

`configs/nsh/defconfig`: Build Config for `ox64:nsh`

### Updated Documentation

`platforms/risc-v/bl808/index.rst`: New page for Bouffalo Lab BL808 SoC

`platforms/risc-v/bl808/boards/ox64/index.rst`: Building and booting NuttX for Ox64

`platforms/risc-v/jh7110/boards/star64/index.rst`: Fix typo

Documentation/platforms/risc-v/bl808/boards/ox64/index.rst

@@ -0,0 +1,149 @@
+===========
+PINE64 Ox64
+===========
+
+`Ox64 <https://wiki.pine64.org/wiki/Ox64>`_ is a RISC-V Single-Board Computer
+based on the Bouffalo Lab BL808 RISC-V SoC with C906 64-bit CPU Core and
+E907 / E902 32-bit CPU Cores supported by 64 MB of embedded PSRAM memory,
+with built-in WiFi, Bluetooth and Zigbee radio interfaces.
+
+Ox64 comes in a breadboard-friendly form factor. It has a microSD Card slot,
+USB 2.0 Type-C port and other peripheral interfaces.
+
+Features
+========
+
+- **System on Chip:** Bouffalo Lab BL808
+    - **CPU:** 
+        - 64-bit T-Head C906 "D0" (RV64IMAFCV)
+        - 32-bit T-Head E907 "M0" (RV32IMAFCP)
+        - 32-bit T-Head E902 "LP" (RV32E[M]C)
+    - **RAM:** Embedded 64 MB PSRAM
+- **Wireless:** 2.4 GHz 1T1R WiFi 802.11 b/g/n, Bluetooth 5.2, Zigbee
+- **Ethernet:** 10 / 100 Mbps (optional)
+- **Storage:** On-board 128 Mbit (16 MB) XSPI NOR Flash Memory, microSD (SDHC and SDXC)
+- **USB:** USB 2.0 OTG
+- **Audio:** Microphone and Speaker (optional)
+- **Video Input:** Dual-lane MIPI CSI port for Camera Module (USB-C)
+- **Expansion Ports:** 26 GPIO pins (including SPI, I2C and UART)
+
+Serial Console
+==============
+
+A **USB Serial Adapter** that supports 2 Mbps (like `CH340G Serial Adapter <https://lupyuen.github.io/articles/ox64#test-the-usb-serial-adapter>`_)
+is required to run NuttX on Ox64.
+
+Connect the USB Serial Adapter to Ox64 Serial Console at:
+
+========== ========
+USB Serial Ox64 Pin
+========== ========
+TX         Pin 31 (GPIO 17 / UART3 RX)
+RX         Pin 32 (GPIO 16 / UART3 TX)
+GND        Pin 33 (GND)
+========== ========
+
+On the USB Serial Adapter, set the **Voltage Level** to 3V3.
+
+Connect Ox64 to our computer with the USB Serial Adapter.
+On our computer, start a Serial Terminal and connect to the USB Serial Port
+at **2 Mbps**.
+
+NuttX will appear in the Serial Console when it boots on Ox64.
+
+RISC-V Toolchain
+================
+
+Before building NuttX for Ox64, download the **RISC-V Toolchain riscv64-unknown-elf**
+from `SiFive RISC-V Tools <https://github.com/sifive/freedom-tools/releases/tag/v2020.12.0>`_.
+
+Add the downloaded toolchain ``riscv64-unknown-elf-toolchain-.../bin``
+to the ``PATH`` Environment Variable.
+
+Check the RISC-V Toolchain:
+
+.. code:: console
+
+   $ riscv64-unknown-elf-gcc -v
+
+Building
+========
+
+To build NuttX for Ox64, :doc:`install the prerequisites </quickstart/install>` and
+:doc:`clone the git repositories </quickstart/install>` for ``nuttx`` and ``apps``.
+
+Configure the NuttX project and build the project:
+
+.. code:: console
+
+   $ cd nuttx
+   $ tools/configure.sh ox64:nsh
+   $ make
+   $ riscv64-unknown-elf-objcopy -O binary nuttx nuttx.bin
+
+This produces the NuttX Kernel ``nuttx.bin``.  Next, build the NuttX Apps Filesystem:
+
+.. code:: console
+
+   $ make export
+   $ pushd ../apps
+   $ tools/mkimport.sh -z -x ../nuttx/nuttx-export-*.tar.gz
+   $ make import
+   $ popd
+   $ genromfs -f initrd -d ../apps/bin -V "NuttXBootVol"
+
+This generates the Initial RAM Disk ``initrd``.
+
+Package the NuttX Kernel and Initial RAM Disk into a NuttX Image:
+
+.. code:: console
+
+   $ head -c 65536 /dev/zero >/tmp/nuttx.pad
+   $ cat nuttx.bin /tmp/nuttx.pad initrd >Image
+
+The NuttX Image ``Image`` will be copied to a microSD Card in the next step.
+
+Booting
+=======
+
+To boot NuttX on Ox64, flash
+`OpenSBI and U-Boot Bootloader <https://lupyuen.github.io/articles/ox64>`_ to Ox64.
+
+NuttX boots on Star64 via a microSD Card. Prepare a
+`Linux microSD Card <https://lupyuen.github.io/articles/ox64>`_ for Ox64.
+
+Copy the file ``Image`` from the previous section
+and overwrite the file on the microSD Card.
+
+Check that Ox64 is connected to our computer via a USB Serial Adapter at 2 Mbps.
+
+Insert the microSD Card into Ox64 and power up Ox64 via the Micro USB Port.
+NuttX boots on Ox64 and NuttShell (nsh) appears in the Serial Console.
+
+To see the available commands in NuttShell:
+
+.. code:: console
+
+   $ help
+
+Configurations
+==============
+
+nsh
+---
+
+Basic configuration that runs NuttShell (nsh).
+This configuration is focused on low level, command-line driver testing.
+Built-in applications are supported, but none are enabled.
+Serial Console is enabled on UART3 at 2 Mbps.
+
+Peripheral Support
+==================
+
+NuttX for Ox64 supports these peripherals:
+
+======================== ======= =====
+Peripheral               Support NOTES
+======================== ======= =====
+UART                     Yes
+======================== ======= =====

Documentation/platforms/risc-v/bl808/index.rst

@@ -0,0 +1,45 @@
+==================
+Bouffalo Lab BL808
+==================
+
+`Bouffalo Lab BL808 <https://github.com/bouffalolab/bl_docs/tree/main/BL808_RM/en>`_ is a 64-bit / 32-bit RISC-V SoC with 3 RISC-V Cores:
+
+- **D0 Multimedia Core:** T-Head C906 480 MHz 64-bit RISC-V CPU
+    - RV64IMAFCV
+    - Level 1 Instruction and Data Cache (Harvard architecture)
+    - Sv39 Memory Management Unit
+    - jTLB (128 entries)
+    - AXI 4.0 128-bit master interface
+    - Core Local Interrupt (CLINT) and Platform-Level Interrupt Controller (PLIC)
+    - 80 External Interrupt Sources
+    - BHT (8K) and BTB
+    - RISC-V PMP (8 configurable areas)
+
+- **M0 Wireless Core:** T-Head E907 320 MHz 32-bit RISC-V CPU
+    - RV32IMAFCP
+    - 32-bit / 16-bit Mixed Instruction Set
+    - RISC-V Machine Mode and User Mode
+    - 32 x 32-bit Integer General Purpose Registers (GPR)
+    - 32 x 32-bit / 64-bit Floating-Point GPRs
+    - AXI 4.0 main device interface and AHB 5.0 peripheral interface
+    - Instruction and Data Cache
+
+- **LP Low Power Core:** T-Head E902 150 MHz 32-bit RISC-V CPU
+    - RV32E[M]C
+
+- **RAM:** Embedded 64 MB PSRAM
+- **Wireless:** 2.4 GHz 1T1R WiFi 802.11 b/g/n, Bluetooth 5.2, Zigbee
+- **Ethernet:** 10 / 100 Mbps
+- **USB:** USB 2.0 OTG
+- **Audio:** Microphone and Speaker
+- **Video Input:** Dual-lane MIPI CSI
+- **Peripherals:** UART, SPI, I2C, PWM, SDH, EMAC, USB
+
+Supported Boards
+================
+
+.. toctree::
+   :glob:
+   :maxdepth: 1
+
+   boards/*/*

Documentation/platforms/risc-v/jh7110/boards/star64/index.rst

@@ -211,7 +211,7 @@ Serial Console is enabled on UART0 at 115.2 kbps.
 Peripheral Support
 ==================
 
-NuttX for PinePhone supports these peripherals:
+NuttX for Star64 supports these peripherals:
 
 ======================== ======= =====
 Peripheral               Support NOTES

boards/Kconfig

@@ -1947,6 +1947,13 @@ config ARCH_BOARD_JH7110_STAR64
 		This options selects support for NuttX on PINE64 Star64 based
 		on StarFive JH7110 SoC.
 
+config ARCH_BOARD_BL808_OX64
+	bool "PINE64 Ox64"
+	depends on ARCH_CHIP_BL808
+	---help---
+		This options selects support for NuttX on PINE64 Ox64 based
+		on Bouffalo Lab BL808 SoC.
+
 config ARCH_BOARD_S32K118EVB
 	bool "NXP S32K118EVB"
 	depends on ARCH_CHIP_S32K118
@@ -3260,6 +3267,7 @@ config ARCH_BOARD
 	default "rv32m1-vega"               if ARCH_BOARD_RV32M1_VEGA
 	default "rv-virt"                   if ARCH_BOARD_QEMU_RV_VIRT
 	default "star64"                    if ARCH_BOARD_JH7110_STAR64
+	default "ox64"                      if ARCH_BOARD_BL808_OX64
 	default "sabre-6quad"               if ARCH_BOARD_SABRE_6QUAD
 	default "qemu-armv7a"               if ARCH_BOARD_QEMU_ARMV7A
 	default "qemu-armv8a"               if ARCH_BOARD_QEMU_ARMV8A
@@ -4151,6 +4159,9 @@ endif
 if ARCH_BOARD_JH7110_STAR64
 source "boards/risc-v/jh7110/star64/Kconfig"
 endif
+if ARCH_BOARD_BL808_OX64
+source "boards/risc-v/bl808/ox64/Kconfig"
+endif
 if ARCH_BOARD_ESP32C3_DEVKIT
 source "boards/risc-v/esp32c3/esp32c3-devkit/Kconfig"
 endif

boards/risc-v/bl808/ox64/configs/nsh/defconfig

@@ -0,0 +1,84 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_DISABLE_OS_API is not set
+# CONFIG_NSH_DISABLE_LOSMART is not set
+# CONFIG_STANDARD_SERIAL is not set
+CONFIG_ARCH="risc-v"
+CONFIG_ARCH_ADDRENV=y
+CONFIG_ARCH_BOARD="ox64"
+CONFIG_ARCH_BOARD_BL808_OX64=y
+CONFIG_ARCH_CHIP="bl808"
+CONFIG_ARCH_CHIP_BL808=y
+CONFIG_ARCH_DATA_NPAGES=128
+CONFIG_ARCH_DATA_VBASE=0x80100000
+CONFIG_ARCH_HEAP_NPAGES=128
+CONFIG_ARCH_HEAP_VBASE=0x80200000
+CONFIG_ARCH_INTERRUPTSTACK=2048
+CONFIG_ARCH_KERNEL_STACKSIZE=3072
+CONFIG_ARCH_PGPOOL_MAPPING=y
+CONFIG_ARCH_PGPOOL_PBASE=0x50600000
+CONFIG_ARCH_PGPOOL_SIZE=4194304
+CONFIG_ARCH_PGPOOL_VBASE=0x50600000
+CONFIG_ARCH_RISCV=y
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_ARCH_TEXT_NPAGES=128
+CONFIG_ARCH_TEXT_VBASE=0x80000000
+CONFIG_ARCH_USE_MMU=y
+CONFIG_ARCH_USE_MPU=y
+CONFIG_ARCH_USE_S_MODE=y
+CONFIG_BL808_UART3=y
+CONFIG_BOARDCTL_ROMDISK=y
+CONFIG_BOARD_LATE_INITIALIZE=y
+CONFIG_BOARD_LOOPSPERMSEC=116524
+CONFIG_BUILD_KERNEL=y
+CONFIG_DEBUG_ASSERTIONS=y
+CONFIG_DEBUG_ASSERTIONS_EXPRESSION=y
+CONFIG_DEBUG_FEATURES=y
+CONFIG_DEBUG_FULLOPT=y
+CONFIG_DEBUG_SYMBOLS=y
+CONFIG_DEV_ZERO=y
+CONFIG_ELF=y
+CONFIG_EXAMPLES_HELLO=m
+CONFIG_FS_PROCFS=y
+CONFIG_FS_ROMFS=y
+CONFIG_IDLETHREAD_STACKSIZE=3072
+CONFIG_INIT_FILEPATH="/system/bin/init"
+CONFIG_INIT_MOUNT=y
+CONFIG_INIT_MOUNT_FLAGS=0x1
+CONFIG_INIT_MOUNT_TARGET="/system/bin"
+CONFIG_INIT_STACKSIZE=3072
+CONFIG_INTELHEX_BINARY=y
+CONFIG_LIBC_ENVPATH=y
+CONFIG_LIBC_EXECFUNCS=y
+CONFIG_LIBC_PERROR_STDOUT=y
+CONFIG_LIBC_STRERROR=y
+CONFIG_MEMSET_64BIT=y
+CONFIG_MEMSET_OPTSPEED=y
+CONFIG_MM_PGALLOC=y
+CONFIG_NFILE_DESCRIPTORS_PER_BLOCK=6
+CONFIG_NSH_ARCHINIT=y
+CONFIG_NSH_FILEIOSIZE=512
+CONFIG_NSH_FILE_APPS=y
+CONFIG_NSH_READLINE=y
+CONFIG_PATH_INITIAL="/system/bin"
+CONFIG_RAM_SIZE=1048576
+CONFIG_RAM_START=0x50200000
+CONFIG_READLINE_CMD_HISTORY=y
+CONFIG_RR_INTERVAL=200
+CONFIG_SCHED_LPWORK=y
+CONFIG_SCHED_WAITPID=y
+CONFIG_STACK_COLORATION=y
+CONFIG_START_MONTH=12
+CONFIG_START_YEAR=2021
+CONFIG_SYMTAB_ORDEREDBYNAME=y
+CONFIG_SYSTEM_NSH=y
+CONFIG_SYSTEM_NSH_PROGNAME="init"
+CONFIG_TESTING_GETPRIME=y
+CONFIG_UART3_BAUD=2000000
+CONFIG_UART3_SERIAL_CONSOLE=y
+CONFIG_USEC_PER_TICK=1000