[PATCH v5 0/3] Add riscv semihosting support in u-boot

[Bin Meng]

On Tue, Nov 29, 2022 at 2:58 PM Kautuk Consul <kconsul at ventanamicro.com> wrote:
>
> I have tested it both on Qemu and Ventana's internal simulator.

How to verify this? I used your instructions and U-Boot says: No match
for driver 'serial_semihosting'

U-Boot 2023.01-rc2-00113-g2a4accaf5e (Dec 03 2022 - 12:20:20 +0800)
CPU: rv64imafdch_zicsr_zifencei_zihintpause_zba_zbb_zbc_zbs_sstc
Model: riscv-virtio,qemu
DRAM: 256 MiB
No match for driver 'serial_semihosting'
Some drivers were not found
Core: 25 devices, 12 uclasses, devicetree: board
Flash: 32 MiB
Loading Environment from nowhere... OK
In: serial at 10000000
Out: serial at 10000000
Err: serial at 10000000
Net: No ethernet found.
Working FDT set to 8f734950
Hit any key to stop autoboot: 0
=>

>
> On Tue, Nov 29, 2022 at 12:06 PM Bin Meng <bmeng.cn at gmail.com> wrote:
>>
>> Hi Kautuk,
>>
>> On Tue, Nov 29, 2022 at 2:29 PM Kautuk Consul <kconsul at ventanamicro.com> wrote:
>> >
>> > Hi,
>> >
>> > Can someone pick this patchset up ?
>> >
>> > It has been reviewed and there has been no comment on this in recent days.
>> >
>> > Thanks.
>> >
>> > On Fri, Sep 23, 2022 at 12:33 PM Kautuk Consul <kconsul at ventanamicro.com> wrote:
>> >>
>> >> Semihosting is a mechanism that enables code running on
>> >> a target to communicate and use the Input/Output
>> >> facilities on a host computer that is running a debugger.
>> >> This patchset adds support for semihosting in u-boot
>> >> for RISCV64 targets.
>> >>
>> >> CHANGES since v4:
>> >> -       Check arch dependencies for SEMIHOSTING as well as SPL_SEMIHOSTING
>> >>         config options as per Sean's comment.
>> >> -       arch/riscv/lib/interrupts.c: Check for post and pre instructions
>> >>         of the ebreak statement whether they are as per the RISCV
>> >>         semihosting specification. Only then do a disable_semihosting
>> >>         and epc += 4 and return.
>> >>
>> >> Compilation and test commands for SPL and S-mode configurations
>> >> =================================================================
>> >>
>> >> U-Boot S-mode on QEMU virt
>> >> ----------------------------
>> >> // Compilation of S-mode u-boot
>> >> ARCH=riscv
>> >> CROSS_COMPILE=riscv64-unknown-linux-gnu-
>> >> make qemu-riscv64_smode_defconfig
>> >> make
>> >> // Run riscv 64-bit u-boot with opensbi on qemu
>> >> qemu-system-riscv64 -M virt -m 256M -display none -serial stdio -bios\
>> >> opensbi/build/platform/generic/firmware/fw_jump.bin -kernel\
>> >> u-boot/u-boot.bin
>> >>
>> >> U-Boot SPL on QEMU virt
>> >> ------------------------
>> >> // Compilation of u-boot-spl
>> >> ARCH=riscv
>> >> CROSS_COMPILE=riscv64-unknown-linux-gnu-
>> >> make qemu-riscv64_spl_defconfig
>> >> make OPENSBI=opensbi/build/platform/generic/firmware/fw_dynamic.bin
>> >> // Run 64-bit u-boot-spl in qemu
>> >> qemu-system-riscv64 -M virt -m 256M -display none -serial stdio -bios\
>> >> u-boot/spl/u-boot-spl.bin -device\
>> >> loader,file=u-boot/u-boot.itb,addr=0x80200000
>> >>
>>
>> Do you have instructions on how to actually test semihosting? Does it
>> require a JTAG debugger? But I see you are using QEMU?
>>

Regards,
Bin