Lup Yuen Lee 李立源 @lupyuen@qoto.org

Apache #NuttX on #Ox64 BL808 Emulator makes a #RISCV ECALL System Call ... Here's why it fails

Article: https://lupyuen.codeberg.page/articles/tinyemu2.html#machine-mode-vs-supervisor-mode

#Ox64 BL808 Emulator runs Apache #NuttX RTOS in the Web Browser ... Just compile #TinyEMU Emulator to WebAssembly (with Emscripten)

Article: https://lupyuen.codeberg.page/articles/tinyemu2.html#emulator-in-the-web-browser

#Ox64 BL808 Emulator hits a #RISCV ECALL Exception in Apache #NuttX RTOS ... Let's find out why

Article: https://lupyuen.codeberg.page/articles/tinyemu2.html#risc-v-exception-in-emulator

UART Output works OK in #Ox64 BL808 Emulator ... But ECALL crashes with a #RISCV Exception

Article: https://lupyuen.codeberg.page/articles/tinyemu2.html#emulator-prints-to-console

Emulating the UART Output for #Ox64 BL808 SBC

Article: https://lupyuen.codeberg.page/articles/tinyemu2.html#emulate-the-uart-output

Here's how we intercept the #BL808 UART Registers ... And emulate the #Ox64 UART Controller

Article: https://lupyuen.codeberg.page/articles/tinyemu2.html#intercept-the-uart-registers

Super excited to be a Mentor for #GSoC 👍

Google Summer of Code: https://summerofcode.withgoogle.com/

Let's emulate the UART Registers for #BL808 SoC inside #Ox64 SBC

Article: https://lupyuen.codeberg.page/articles/tinyemu2.html#uart-registers-for-bl808-soc

Apache #NuttX RTOS boots OK in our #Ox64 BL808 Emulator!

Article: https://lupyuen.codeberg.page/articles/tinyemu2.html#run-tinyemu-emulator

#RISCV "Wait for Interrupt instruction (WFI) provides a hint to the implementation that the current hart can be stalled until an interrupt ... so a legal implementation is to simply implement WFI as a NOP" 🤔

Source: https://github.com/riscv/riscv-isa-manual/releases/download/Priv-v1.12/riscv-privileged-20211203.pdf

Fixing the #RISCV Addresses in TinyEMU Emulator ... To match the Bouffalo Lab #BL808 SoC inside #Ox64

Article: https://lupyuen.codeberg.page/articles/tinyemu2.html#change-risc-v-addresses-in-tinyemu

Upcoming #RustLang support in #Zephyr OS

Source: https://github.com/zephyrproject-rtos/zephyr/issues/65837

Let's install TinyEMU #RISCV Emulator ... And tweak it to emulate #Ox64 BL808 SBC

Article: https://lupyuen.codeberg.page/articles/tinyemu2.html#install-tinyemu-emulator

🤔 "Summarise the discussion on #RustLang in #NuttX"

Let's create a barebones @PINE64 #Ox64 BL808 Emulator that runs in the Web Browser ... By tweaking TinyEMU #RISCV Emulator and booting Apache #NuttX RTOS

Article: https://lupyuen.codeberg.page/articles/tinyemu2

How we run a #RustLang App on Apache #NuttX RTOS (QEMU #RISCV)

Source: https://gist.github.com/lupyuen/7be4bedc6a109b2c3d1201aee6030428

Building Apache #NuttX RTOS for TinyEMU #RISCV Emulator

Article: https://lupyuen.codeberg.page/articles/tinyemu.html#appendix-build-nuttx-for-tinyemu

Upcoming: #RustLang for Apache #NuttX RTOS 👍

Source: https://github.com/apache/nuttx/issues/11907

Apache #NuttX RTOS talks to #VirtIO Devices ... By calling #OpenAMP Library

Article: https://lupyuen.codeberg.page/articles/tinyemu.html#nuttx-with-virtio-and-openamp

#TinyEMU Emulator might have a problem with Global Page Table Entries in #RISCV MMU 🤔

Source: https://github.com/lupyuen2/wip-pinephone-nuttx/blob/on-demand-paging3/README.md#uart-io-fails-on-tinyemu