Hi François, On Wed, 27 Oct 2021 at 14:07, François Ozog <francois.o...@linaro.org> wrote: > > Hi Simon > > Le mer. 27 oct. 2021 à 20:23, Simon Glass <s...@chromium.org> a écrit : >> >> Hi François, >> >> On Wed, 27 Oct 2021 at 09:14, François Ozog <francois.o...@linaro.org> wrote: >> > >> > >> > >> > On Wed, 27 Oct 2021 at 16:08, Simon Glass <s...@chromium.org> wrote: >> >> >> >> Hi François, >> >> >> >> On Tue, 26 Oct 2021 at 00:07, François Ozog <francois.o...@linaro.org> >> >> wrote: >> >> > >> >> > Hi Simon >> >> > >> >> > Position unchanged on this series: adding fake dts for boards that >> >> > generate their device tree in the dts directory is not good. If you >> >> > have them in documentation the it is acceptable. >> >> >> >> I think we are going to have to disagree on this one. I actually used >> >> the qemu one in testing/development recently. We have to have a way to >> >> develop in-tree with U-Boot. It does not impinge on any of your use >> >> cases, so far as I know. >> > >> > I am not the only one in disagreement... You just saw Alex Bénée from Qemu >> > saying the same thing. >> > I understand the advanced debug/development scenario you mention. >> > But locating the DT files in the dts directory is mis-leading the >> > contributors to think that they need to compile the DT for the targeted >> > platforms. >> > For your advanced scenario, you can still have the dts in the >> > documentation area, or whatever directory (except dts). compile it and >> > supply to U-Boot. >> >> We have this situation with rpi 1, 2 and 3 and I don't believe anyone >> has noticed. U-Boot handles the build automatically. If you turn off >> OF_BOARD, it will use the U-Boot devicetree always so you know what is >> going on. >> >> We can add a message to U-Boot indicating where the devicetree came >> from, perhaps? That might be useful given everything that is going on. >> >> As in this case, quite often in these discussions I struggle to >> understand what is behind the objection. Is it that your customers are >> demanding that devicetrees become private, secret data, not included >> in open-source projects? Or is it just the strange case of QEMU that >> is informing your thinking? I know of at least one project where the >> first-stage bootloader produces a devicetree and no one has the source >> for it. I believe TF-A was created for licensing reasons...so can you >> be a bit clearer about what the problem actually is? > > there are situations where U-Boot must have a dtb. Then those dTB sources are > logically found in the dts directory. > There are situations where U-Boot should not have a dtb. In that case there > should be no element in the dts directory. Otherwise it creates confusion. > Now as you point out, we need “playgrounds” to deal with some situation. So > having examples in an ad-hoc directory, different from dts is fine. I > proposed documentation but you may find a better place. > In other words, dts shall host only dt source when U-Boot cannot do but make > a dTB for a platform. > As you have seen in different mail thread (firmware sustainability and OCP > checklist) freedom is important to Linaro and there are no hidden Trojan > horse for licensing.
I don't understand what you are getting at with the Trojan horse. But you have no objection to requiring boards to supply a DT (whether in documentation or arch/arm/dts) to be in U-Boot? > > >> If a board is >> in-tree in U-Boot I would like it to have a devicetree there, at least >> until we have a better option. At the very least, it MUST be >> discoverable and it must be possible to undertake U-Boot development >> easily without a lot of messing around. > > You can if you keep two dts directories separate: > dts for boards for which U-Boot must have one > debug-dts for boards for which U-Boot get the DT at runtime but for which you > want a playground for debug/easier development. >> >> >> >> >> >> >> >> But trying to do any driver / core work for a board where you don't >> >> have the devicetree is currently not possible. The devicetree is a >> >> core component and being unable to modify it is simply not practical. >> >> We are talking here about an option that can be enabled or disabled. >> >> In my case I am able to disable it locally and do my development work. >> >> >> >> >> >> BTW I've got the bloblist handoff working with a devicetree inside it, >> >> for qemu_arm. I need to try it on a real board to figure out what the >> >> difference is. >> >> >> > That's great news and much needed for stabilizing the inbound ABI from >> > prior loader to U-Boot. Let's create another thread to discuss this >> > important topic. >> >> >> >> My scenario is not all that advanced and I am using qemu_arm to test >> the bloblist handoff stuff and include it in CI, with a suitable >> devicetree and a binman node. >> >> Regards, >> Simon >> >> >> > >> >> > Cheers >> >> > >> >> > FF >> >> > >> >> > Le mar. 26 oct. 2021 à 02:24, Simon Glass <s...@chromium.org> a écrit : >> >> >> >> >> >> With Ilias' efforts we have dropped OF_PRIOR_STAGE and OF_HOSTFILE so >> >> >> there are only three ways to obtain a devicetree: >> >> >> >> >> >> - OF_SEPARATE - the normal way, where the devicetree is built and >> >> >> appended to U-Boot >> >> >> - OF_EMBED - for development purposes, the devicetree is embedded in >> >> >> the ELF file (also used for EFI) >> >> >> - OF_BOARD - the board figures it out on its own >> >> >> >> >> >> The last one is currently set up so that no devicetree is needed at all >> >> >> in the U-Boot tree. Most boards do provide one, but some don't. Some >> >> >> don't even provide instructions on how to boot on the board. >> >> >> >> >> >> The problems with this approach are documented in another patch in this >> >> >> series: "doc: Add documentation about devicetree usage" >> >> >> >> >> >> In practice, OF_BOARD is not really distinct from OF_SEPARATE. Any >> >> >> board >> >> >> can obtain its devicetree at runtime, even it is has a devicetree built >> >> >> in U-Boot. This is because U-Boot may be a second-stage bootloader and >> >> >> its >> >> >> caller may have a better idea about the hardware available in the >> >> >> machine. >> >> >> This is the case with a few QEMU boards, for example. >> >> >> >> >> >> So it makes no sense to have OF_BOARD as a 'choice'. It should be an >> >> >> option, available with either OF_SEPARATE or OF_EMBED. >> >> >> >> >> >> This series makes this change, adding various missing devicetree files >> >> >> (and placeholders) to make the build work. >> >> >> >> >> >> Note: If board maintainers are able to add their own patch to add the >> >> >> files, some patches in this series can be dropped. >> >> >> >> >> >> It also provides a few qemu clean-ups discovered along the way. >> >> >> >> >> >> Note: This breaks the qemu-riscv64_spl test, which still needs >> >> >> investigation. >> >> >> >> >> >> [1] >> >> >> https://patchwork.ozlabs.org/project/uboot/patch/20210919215111.3830278-3-...@chromium.org/ >> >> >> >> >> >> Changes in v5: >> >> >> - Bring into the OF_BOARD series >> >> >> - Rebase to master and drop mention of OF_PRIOR_STAGE, since removed >> >> >> - Refer to the 'control' DTB in the first paragraph >> >> >> - Use QEMU instead of qemu >> >> >> - Merge RISC-V and ARM patches since they are similar >> >> >> - Add new patches to clean up fdtdec_setup() and surrounds >> >> >> >> >> >> Changes in v3: >> >> >> - Clarify the 'bug' refered to at the top >> >> >> - Reword 'This means that there' paragraph to explain U-Boot-specific >> >> >> things >> >> >> - Move to doc/develop/devicetree now that OF_CONTROL is in the docs >> >> >> >> >> >> Changes in v2: >> >> >> - Fix typos per Sean (thank you!) and a few others >> >> >> - Add a 'Use of U-Boot /config node' section >> >> >> - Drop mention of dm-verity since that actually uses the kernel cmdline >> >> >> - Explain that OF_BOARD will still work after these changes (in >> >> >> 'Once this bug is fixed...' paragraph) >> >> >> - Expand a bit on the reason why the 'Current situation' is bad >> >> >> - Clarify in a second place that Linux and U-Boot use the same >> >> >> devicetree >> >> >> in 'To be clear, while U-Boot...' >> >> >> - Expand on why we should have rules for other projects in >> >> >> 'Devicetree in another project' >> >> >> - Add a comment as to why devicetree in U-Boot is not 'bad design' >> >> >> - Reword 'in-tree U-Boot devicetree' to 'devicetree source in U-Boot' >> >> >> - Rewrite 'Devicetree generated on-the-fly in another project' to cover >> >> >> points raised on v1 >> >> >> - Add 'Why does U-Boot have its nodes and properties?' >> >> >> - Add 'Why not have two devicetrees?' >> >> >> >> >> >> Ilias Apalodimas (1): >> >> >> sandbox: Remove OF_HOSTFILE >> >> >> >> >> >> Simon Glass (25): >> >> >> doc: Add documentation about devicetree usage >> >> >> arm: qemu: Mention -nographic in the docs >> >> >> arm: riscv: qemu: Explain how to extract the generated dt >> >> >> arm: qemu: Add a devicetree file for qemu_arm >> >> >> arm: qemu: Add a devicetree file for qemu_arm64 >> >> >> riscv: qemu: Add devicetree files for qemu_riscv32/64 >> >> >> arm: rpi: Add a devicetree file for rpi_4 >> >> >> arm: vexpress: Add a devicetree file for juno >> >> >> arm: xenguest_arm64: Add a fake devicetree file >> >> >> arm: octeontx: Add a fake devicetree file >> >> >> arm: xilinx_versal_virt: Add a devicetree file >> >> >> arm: bcm7xxx: Add a devicetree file >> >> >> arm: qemu-ppce500: Add a devicetree file >> >> >> arm: highbank: Add a fake devicetree file >> >> >> fdt: Make OF_BOARD a bool option >> >> >> Drop CONFIG_BINMAN_STANDALONE_FDT >> >> >> doc: Update info on devicetree update >> >> >> fdt: Move MULTI_DTB_FIT handling out of fdtdec_setup() >> >> >> fdt: Drop #ifdefs with MULTI_DTB_FIT >> >> >> fdt: Drop CONFIG_SPL_BUILD check in fdtdec_setup() >> >> >> fdt: Drop #ifdef around board_fdt_blob_setup() >> >> >> fdt: Use if() for fdtcontroladdr check >> >> >> fdt: Drop OF_CONTROL check in fdtdec_setup() >> >> >> fdt: Drop remaining preprocessor macros in fdtdec_setup() >> >> >> fdt: Don't call board_fdt_blob_setup() without OF_BOARD >> >> >> >> >> >> Makefile | 7 +- >> >> >> arch/arm/dts/Makefile | 20 +- >> >> >> arch/arm/dts/bcm2711-rpi-4-b.dts | 1958 +++++++++++++++++++++ >> >> >> arch/arm/dts/bcm7xxx.dts | 15 + >> >> >> arch/arm/dts/highbank.dts | 14 + >> >> >> arch/arm/dts/juno-r2.dts | 1038 +++++++++++ >> >> >> arch/arm/dts/octeontx.dts | 14 + >> >> >> arch/arm/dts/qemu-arm.dts | 402 +++++ >> >> >> arch/arm/dts/qemu-arm64.dts | 381 ++++ >> >> >> arch/arm/dts/xenguest-arm64.dts | 15 + >> >> >> arch/arm/dts/xilinx-versal-virt.dts | 307 ++++ >> >> >> arch/powerpc/dts/Makefile | 1 + >> >> >> arch/powerpc/dts/qemu-ppce500.dts | 264 +++ >> >> >> arch/riscv/dts/Makefile | 2 +- >> >> >> arch/riscv/dts/qemu-virt.dts | 8 - >> >> >> arch/riscv/dts/qemu-virt32.dts | 217 +++ >> >> >> arch/riscv/dts/qemu-virt64.dts | 217 +++ >> >> >> arch/sandbox/cpu/cpu.c | 21 +- >> >> >> arch/sandbox/include/asm/u-boot-sandbox.h | 8 - >> >> >> configs/bcm7260_defconfig | 1 + >> >> >> configs/bcm7445_defconfig | 1 + >> >> >> configs/highbank_defconfig | 2 +- >> >> >> configs/octeontx2_95xx_defconfig | 1 + >> >> >> configs/octeontx2_96xx_defconfig | 1 + >> >> >> configs/octeontx_81xx_defconfig | 1 + >> >> >> configs/octeontx_83xx_defconfig | 1 + >> >> >> configs/qemu-ppce500_defconfig | 2 + >> >> >> configs/qemu-riscv32_defconfig | 1 + >> >> >> configs/qemu-riscv32_smode_defconfig | 1 + >> >> >> configs/qemu-riscv32_spl_defconfig | 4 +- >> >> >> configs/qemu-riscv64_defconfig | 1 + >> >> >> configs/qemu-riscv64_smode_defconfig | 1 + >> >> >> configs/qemu-riscv64_spl_defconfig | 3 +- >> >> >> configs/qemu_arm64_defconfig | 1 + >> >> >> configs/qemu_arm_defconfig | 1 + >> >> >> configs/rpi_4_32b_defconfig | 1 + >> >> >> configs/rpi_4_defconfig | 1 + >> >> >> configs/rpi_arm64_defconfig | 1 + >> >> >> configs/sandbox64_defconfig | 2 +- >> >> >> configs/sandbox_defconfig | 2 +- >> >> >> configs/sandbox_flattree_defconfig | 2 +- >> >> >> configs/sandbox_noinst_defconfig | 2 +- >> >> >> configs/sandbox_spl_defconfig | 2 +- >> >> >> configs/tools-only_defconfig | 2 +- >> >> >> configs/vexpress_aemv8a_juno_defconfig | 1 + >> >> >> configs/xenguest_arm64_defconfig | 1 + >> >> >> configs/xilinx_versal_virt_defconfig | 1 + >> >> >> doc/board/emulation/qemu-arm.rst | 10 +- >> >> >> doc/board/emulation/qemu-riscv.rst | 3 + >> >> >> doc/develop/devicetree/control.rst | 7 +- >> >> >> doc/develop/devicetree/dt_qemu.rst | 48 + >> >> >> doc/develop/devicetree/dt_update.rst | 498 ++++++ >> >> >> doc/develop/devicetree/index.rst | 2 + >> >> >> dts/Kconfig | 37 +- >> >> >> include/asm-generic/global_data.h | 8 + >> >> >> include/fdtdec.h | 21 +- >> >> >> lib/fdtdec.c | 116 +- >> >> >> scripts/Makefile.spl | 4 +- >> >> >> tools/binman/binman.rst | 20 - >> >> >> 59 files changed, 5560 insertions(+), 164 deletions(-) >> >> >> create mode 100644 arch/arm/dts/bcm2711-rpi-4-b.dts >> >> >> create mode 100644 arch/arm/dts/bcm7xxx.dts >> >> >> create mode 100644 arch/arm/dts/highbank.dts >> >> >> create mode 100644 arch/arm/dts/juno-r2.dts >> >> >> create mode 100644 arch/arm/dts/octeontx.dts >> >> >> create mode 100644 arch/arm/dts/qemu-arm.dts >> >> >> create mode 100644 arch/arm/dts/qemu-arm64.dts >> >> >> create mode 100644 arch/arm/dts/xenguest-arm64.dts >> >> >> create mode 100644 arch/arm/dts/xilinx-versal-virt.dts >> >> >> create mode 100644 arch/powerpc/dts/qemu-ppce500.dts >> >> >> delete mode 100644 arch/riscv/dts/qemu-virt.dts >> >> >> create mode 100644 arch/riscv/dts/qemu-virt32.dts >> >> >> create mode 100644 arch/riscv/dts/qemu-virt64.dts >> >> >> create mode 100644 doc/develop/devicetree/dt_qemu.rst >> >> >> create mode 100644 doc/develop/devicetree/dt_update.rst >> >> >> >> >> >> -- >> >> >> 2.33.0.1079.g6e70778dc9-goog >> >> >> >> >> > -- >> >> > François-Frédéric Ozog | Director Business Development >> >> > T: +33.67221.6485 >> >> > francois.o...@linaro.org | Skype: ffozog >> >> > >> > >> > >> > >> > -- >> > François-Frédéric Ozog | Director Business Development >> > T: +33.67221.6485 >> > francois.o...@linaro.org | Skype: ffozog >> > > > -- > François-Frédéric Ozog | Director Business Development > T: +33.67221.6485 > francois.o...@linaro.org | Skype: ffozog >
