[U-Boot] [RFC PATCH 00/11] SPL support for RISC-V

[Auer, Lukas]

Hi Bin,

On Wed, 2019-07-24 at 10:55 +0800, Bin Meng wrote:
> Hi Lukas,
> 
> On Wed, Jul 24, 2019 at 5:34 AM Auer, Lukas
> <lukas.auer at aisec.fraunhofer.de> wrote:
> > Hi Bin,
> > 
> > On Tue, 2019-07-23 at 16:32 +0800, Bin Meng wrote:
> > > Hi Lukas,
> > > 
> > > On Mon, Jul 22, 2019 at 2:00 AM Lukas Auer
> > > <lukas.auer at aisec.fraunhofer.de> wrote:
> > > > This series adds support for SPL to RISC-V U-Boot. Images can be booted
> > > > via OpenSBI (FW_DYNAMIC firmware) or by directly jumping to them. In the
> > > > former case, OpenSBI and U-Boot proper are bundled as a FIT image and
> > > > made available to U-Boot SPL. Currently, only the QEMU board enables
> > > > U-Boot SPL with a dedicated configuration. It uses RAM as SPL boot
> > > > device.
> > > > 
> > > > On many RISC-V CPUs, the device tree is provided to U-Boot by the
> > > > first stage bootloader. This requires changes to U-Boot SPL (patches 1,
> > > > 2 and 3), which modify the behavior on other boards as well. To get
> > > > feedback on this, I am therefore sending this series as RFC first.
> > > > 
> > > > To test this series, OpenSBI has to be compiled first. The
> > > > fw_dynamic.bin binary must be copied into the U-Boot root directory.
> > > > Alternatively, the location of the binary can be specified with the
> > > > OPENSBI environment variable. U-Boot can then be build as normal using
> > > > the configuration qemu-riscv64_spl_defconfig for 64-bit builds or
> > > > qemu-riscv32_spl_defconfig for 32-bit builds. The outputs from the build
> > > > process are the U-Boot SPL binary (spl/u-boot-spl.bin) and the U-Boot
> > > > FIT image (u-boot.itb) containing U-Boot proper and OpenSBI.
> > > > 
> > > > U-Boot can be run in QEMU with the following command.
> > > > 
> > > > qemu-system-riscv64 -nographic -machine virt -kernel spl/u-boot-spl \
> > > >         -device loader,file=u-boot.itb,addr=0x80200000
> > > > 
> > > 
> > > Nice job done! It looks the SPL support was cleanly implemented.
> > > 
> > 
> > Thank you very much! :)
> > 
> > > I've tested this series, on qemu-riscv64 with UP and SMP, both work fine.
> > > However when testing on qemu-riscv32, the U-Boot proper does not boot.
> > > Please have a look.
> > > 
> > > Regards,
> > > Bin
> > 
> > Thank you for reviewing and testing the series!
> > 
> > Do you mean that the U-Boot prompt does not appear? Testing the series
> 
> I mean U-Boot proper, the S-mode payload that SPL loads.
> 
> > on qemu-riscv32, I get the U-Boot prompt from U-Boot proper. I did not
> > try to boot Linux on qemu-riscv32, however. I will try that tomorrow.
> 
> After debugging myself, it turns out to be a false alarm. Sorry about that.
> 
> I was using a 64-bit OpenSBI fw_dynamic.bin. Looks OpenSBI doc does
> not clearly mention how 32-bit build is to be done, and I will send a
> patch for that. After switching a 32-bit OpenSBI firmware now I am
> able to boot to 32-bit U-Boot proper.
> 

No problem. You are right, that should be stated more clearly in the
OpenSBI docs. Thanks for testing again!

Thanks,
Lukas