How to run nuttx(kernel build) on real hardware instead of qemu semihosting?

[GooTal]

Hi, i`ve already ported Nuttx(kernel build) to LoongArch referring to qemu-rv:virt.

I notice that qemu-rv:virt used semihosting to load nsh_main`s code into memory from host file system.

But on real hardware, it`s necessary to load nsh_main`s code from disk. I`m trying to figure out how to load the related code.

I`ve successfully run nuttx(flat build) on real hardware. Here`s how i run it: I put the elf file under the /boot/ directory of Linux. And loaded the elf by grub or pmon, then boot the kernel.

I hope to put the nuttx(kernel build) and apps/bin/sh under the /boot/ directory of Linux. And use grub to boot my kernel, too. Is this a feasible way?

Could anyone provide some suggestions? Thanks a lot.

[xiaoxiang781216]

Hi, i`ve already ported Nuttx(kernel build) to LoongArch referring to qemu-rv:virt.

I notice that qemu-rv:virt used semihosting to load nsh_main`s code into memory from host file system.

But on real hardware, its necessary to load nsh_mains code from disk. I`m trying to figure out how to load the related code.

Ive successfully run nuttx(flat build) on real hardware. Heres how i run it: I put the elf file under the /boot/ directory of Linux. And loaded the elf by grub or pmon, then boot the kernel.

I hope to put the nuttx(kernel build) and apps/bin/sh under the /boot/ directory of Linux. And use grub to boot my kernel, too. Is this a feasible way?

Yes, but you need mount /boot inside nuttx before nuttx can launch sh

Could anyone provide some suggestions? Thanks a lot.

If the debugger can connect to your device through JTAG, you can continue use semihosting.

[patacongo]

There are some general instructions for a few ARM platforms. I used the SAMA5D4-EK in the past with the root file system on an SD card. I put instructions in the board README.txt file:

https://github.com/apache/nuttx/blob/master/boards/arm/sama5/sama5d4-ek/README.txt#L4091

That README.txt file also includes instructions for testing with a built-in ROMFS root file system.

I also noticed these using qemu-system-arm:

https://github.com/apache/nuttx/blob/master/boards/arm/imx6/sabre-6quad/README.txt#L892
https://github.com/apache/nuttx/blob/master/boards/arm/imx6/sabre-6quad/README.txt#L929

You could also check the RISC-V board README files to see if instructions were provided:

boards/risc-v/litex/arty_a7/configs/knsh/defconfig:CONFIG_BUILD_KERNEL=y
boards/risc-v/mpfs/icicle/configs/knsh/defconfig:CONFIG_BUILD_KERNEL=y
boards/risc-v/qemu-rv/rv-virt/configs/knetnsh64/defconfig:CONFIG_BUILD_KERNEL=y

[GooTal]

Yes, but you need mount /boot inside nuttx before nuttx can launch sh

But the /boot is on my SSD hard disk and i didn`t find the code for SATA driver in nuttx. Is this still a feasible way?

I can only find out nand flash support. But i`m running on a Desktop CPU so it`s quite troublesome to port SATA driver all over again.😀

If the debugger can connect to your device through JTAG, you can continue use semihosting.

Thanks, but the JTAG doesn`t support it for now.

[patacongo]

But the /boot is on my SSD hard disk and i didn`t find the code for SATA driver in nuttx. Is this still a feasible way?

Probably not. There is no SATA support in NuttX. NAND would not work either because there is no supported NAND-compatible file system.

If you want to use a NuttX native file system, the easiest thing to do would be to use and internal ROMFS file system. I referred to this above:

https://github.com/apache/nuttx/blob/master/boards/arm/sama5/sama5d4-ek/README.txt#L4127

This requires some special initialization logic:

https://github.com/apache/nuttx/blob/master/boards/arm/sama5/sama5d4-ek/src/sam_bringup.c#L233

[GooTal]

If you want to use a NuttX native file system, the easiest thing to do would be to use and internal ROMFS file system. I referred to this above:

https://github.com/apache/nuttx/blob/master/boards/arm/sama5/sama5d4-ek/README.txt#L4127

This requires some special initialization logic:

https://github.com/apache/nuttx/blob/master/boards/arm/sama5/sama5d4-ek/src/sam_bringup.c#L233

Thank you so much.

Could you update the section 6b in this document? I`m not quite familiar with the build method of romfs.

Ha, i built it successfully. Maybe i`ll consider enabling USB as persistent storage device after i enabled the romfs

[lupyuen]

Hi: I have the same question while porting NuttX to Star64 JH7110 SBC.

Fortunately the SBC runs on U-Boot Bootloader, so I'll try to use the Initial RAM Disk (initrd) to load the Apps Filesystem with ROMFS.

Thanks for the suggestions! :-)

Update: NuttX on Star64 JH7110 SBC now boots with Initial RAM Disk (initrd)