Hi Caleb,
On Tue, 21 Nov 2023 at 22:39, Caleb Connolly caleb.connolly@linaro.org wrote:
Historically, Qualcomm boards in U-Boot have all had their own board/qualcomm/xyz directory, their own CONFIG_TARGET_XYZ option, their own hardcoded sysmap-xyz.c file, and their own U-Boot specific devicetree with little/no compatibility with upstream DT.
This series makes a few final prepatory changes, and then replaces almost all of the board specific code with generic alternatives. The end result is that all Qualcomm boards both current and future (with the exception of the db410c and db820c) can be supported by a single U-Boot binary by just providing the correct DT. New boards can be added without introducing any addition mach/ or board/ code or config options.
Due to the nature of this change, the patch ("mach-snapdragon: generalise board support") has become pretty big, I tried a few different ways to represent this in git history, but the other methods (e.g. adding a stub "generic" target and removing it again) were more confusing and made for much messier git history. The current patch is mostly atomic, but requires regenerating the config.
The QCS404 EVB board had some code to enable the USB VBUS regulator, this is dropped in favour of a adding a new vbus-supply property to the dwc3-generic driver. This will also be used by the dragonboard845c in a future patch. This handles the common case of a board requiring some regulator be enabled for USB host mode.
Thanks for your work. It is a good step towards a generalized u-boot on Qcom platforms. Although I would like to give it an in-depth review, I have a common discussion point about DT, see below.
A more detailed description of the changes is below.
== Memory map ==
The memory map was historically hardcoded into U-Boot, this meant that U-Boot had to be built for a specific variant of a device. This is changed to instead read the memory map from the DT /memory node.
Additionally, most boards mapped addresss 0x0 as valid, as a result if a null pointer access happens then it will cause a bus stall (and board hang). This is fixed so that null pointer accesses will now correctly throw an exception.
== DT loading ==
Previously, boards used the FDT blob embedded into U-Boot (via OF_SEPARATE). However, most Qualcomm boards run U-Boot as a secondary bootloader, so we can instead rely on the first-stage bootloader to populate some useful FDT properties for us (notably the /memory node and KASLR seed) and fetch the DTB that it provides. Combined with the memory map changes above, this let's us entirely avoid configuring the memory map explicitly.
Since with this change, we don't need to embed FDT blob in the u-boot binary, so I was thinking if we really need to import DTs from Linux for different platforms and then play a catchup game?
IMO, the build command would look like following if we import pre-built FDT blob from Linux:
- Build u-boot::
$ export CROSS_COMPILE=<aarch64 toolchain prefix> $ make qcom_defconfig $ make
- gzip u-boot::
gzip u-boot-nodtb.bin
- Append dtb to gzipped u-boot::
cat u-boot-nodtb.bin.gz <linux-tree>/arch/arm64/boot/dts/qcom/your-board.dtb > u-boot-nodtb.bin.gz-dtb
This would avoid the maintenance burden to keep DT in sync with that of Linux. And since DT bindings in Linux are backwards compatible, we can say u-boot should work with DTB picked up from any Linux kernel stable release.
-Sumit
== defconfig ==
Most of the board defconfigs and config headers were quite similar, to simplify maintenance going forward, all the fully generic boards (sdm845 and qcs404-evb so far) are adapted to use the new qcom_defconfig. Going forward, all new Qualcomm boards should be supported by this defconfig. A notable exception is for specific usecases (like U-Boot as the primary bootloader).
== The older dragonboards ==
The db410c and db820c both have some custom board init code, as a result they aren't yet binary compatible. mach-snapdragon is adjusted so that all the necessary config options (e.g. CONFIG_SYS_BOARD) can be set from their defconfigs, this makes it possible to enable support for new boards without introducing additional config options.
The db410c can run U-Boot either chainloaded like the other boards, or as a first-stage bootloader replacing aboot. However it was hardcoded to only build for the latter option. This series introduces a new "chainloaded" defconfig to enable easier testing via fastboot.
== dynamic environment variables ==
This series also introduces runtime-allocated load addresses via the lmb allocator. This allows for booting on boards with vastly different memory layouts without any pre-calculation or macro magic in the config header. This feature is based on similar code in mach-apple.
The soc, board, and fdtfile environment variables are also generated automatically. Many Qualcomm boards follow a similar scheme for DTB naming such that the name can often be derived from the root compatible properties. This is intended to cover the most common cases and be a simple solution for booting generic distro images without having to explicitly choose the right DTB. The U-Boot DTS can be tweaked if necessary to produce the correct name, the variable can be overwritten, or a bootloader like GRUB can load the devicetree instead.
== Upstream DT ==
All Qualcomm boards have had their devicetree files rewritten to be based on the upstream SoC/PMIC DTSI files. Previous patch series made the necessary driver adjustments to fully support the upstream DT format. All future Qualcomm boards should use upstream DTS by default.
I have tested this series on the Dragonboard410c, Dragonboard820c, and Dragonboard845c. I unfortunately don't have access to a QCS404 EVB board to test.
This series is based on the qcom-next branch [1] and depends on my PMIC fixes series [2], an integration branch for testing can be found at [3]. The non-qualcomm-specific changes (patches 1, 2, and 3) don't have any dependencies.
To: Neil Armstrong neil.armstrong@linaro.org To: Sumit Garg sumit.garg@linaro.org To: Ramon Fried rfried.dev@gmail.com Cc: Marek Vasut marex@denx.de To: Dzmitry Sankouski dsankouski@gmail.com To: Caleb Connolly caleb.connolly@linaro.org To: Peng Fan peng.fan@nxp.com To: Jaehoon Chung jh80.chung@samsung.com To: Rayagonda Kokatanur rayagonda.kokatanur@broadcom.com To: Lukasz Majewski lukma@denx.de To: Sean Anderson seanga2@gmail.com To: Jorge Ramirez-Ortiz jorge.ramirez.ortiz@gmail.com To: Stephan Gerhold stephan@gerhold.net Cc: u-boot@lists.denx.de
Caleb Connolly (21): arm: init: export prev_bl_fdt_addr arm: allow CONFIG_LINUX_KERNEL_IMAGE_HEADER to be set in defconfig usb: dwc3-generic: support external vbus regulator mmc: msm_sdhci: use modern clock handling dt-bindings: drop msm_sdhci binding clk/qcom: use upstream compatible properties serial: msm: add debug UART serial: msm: fix clock handling configs: add dragonboard410c_chainloaded_defconfig dts: dragonboard410c: fix compatible and clocks board: dragonboard410c: import board code from mach-snapdragon board: dragonboard820c: use LINUX_KERNEL_IMAGE_HEADER mach-snapdragon: generalise board support mach-snapdragon: dynamic load addresses mach-snapdragon: generate fdtfile automatically doc: board/qualcomm: document generic targets dts: sdm845: import DT from Linux dts: msm8916: import DT from Linux dts: msm8996: import DT from Linux dts: qcs404-evb: import DT from Linux MAINTAINERS: Qualcomm: add some missing paths
MAINTAINERS | 16 +- arch/arm/Kconfig | 6 +- arch/arm/dts/Makefile | 9 +- arch/arm/dts/dragonboard410c-uboot.dtsi | 44 - arch/arm/dts/dragonboard410c.dts | 198 +- arch/arm/dts/dragonboard820c-uboot.dtsi | 32 - arch/arm/dts/dragonboard820c.dts | 129 +- arch/arm/dts/dragonboard845c-uboot.dtsi | 26 - arch/arm/dts/dragonboard845c.dts | 23 +- arch/arm/dts/msm8916-pins.dtsi | 582 ++ arch/arm/dts/msm8916-pm8916.dtsi | 76 + arch/arm/dts/msm8916.dtsi | 2194 ++++++++ arch/arm/dts/msm8996.dtsi | 3959 +++++++++++++ arch/arm/dts/pm8916.dtsi | 183 + arch/arm/dts/pm8994.dtsi | 152 + arch/arm/dts/pm8998.dtsi | 130 + arch/arm/dts/pms405.dtsi | 149 + arch/arm/dts/qcs404-evb-uboot.dtsi | 30 - arch/arm/dts/qcs404-evb.dts | 441 +- arch/arm/dts/qcs404.dtsi | 1830 ++++++ arch/arm/dts/sdm845.dtsi | 5850 +++++++++++++++++++- arch/arm/dts/starqltechn-uboot.dtsi | 27 - arch/arm/dts/starqltechn.dts | 34 +- arch/arm/lib/save_prev_bl_data.c | 5 + arch/arm/mach-snapdragon/Kconfig | 95 +- arch/arm/mach-snapdragon/Makefile | 8 +- arch/arm/mach-snapdragon/board.c | 303 + arch/arm/mach-snapdragon/include/mach/dram.h | 12 - arch/arm/mach-snapdragon/init_sdm845.c | 73 - arch/arm/mach-snapdragon/misc.c | 55 - arch/arm/mach-snapdragon/sysmap-apq8016.c | 31 - arch/arm/mach-snapdragon/sysmap-apq8096.c | 31 - arch/arm/mach-snapdragon/sysmap-qcs404.c | 43 - arch/arm/mach-snapdragon/sysmap-sdm845.c | 31 - board/qualcomm/dragonboard410c/Kconfig | 15 - board/qualcomm/dragonboard410c/MAINTAINERS | 1 + board/qualcomm/dragonboard410c/Makefile | 3 +- board/qualcomm/dragonboard410c/dragonboard410c.c | 31 +- .../qualcomm/dragonboard410c/misc.c | 51 +- .../mach => board/qualcomm/dragonboard410c}/misc.h | 1 + board/qualcomm/dragonboard820c/Kconfig | 15 - board/qualcomm/dragonboard820c/Makefile | 1 - board/qualcomm/dragonboard820c/dragonboard820c.c | 39 +- board/qualcomm/dragonboard820c/head.S | 33 - board/qualcomm/dragonboard820c/u-boot.lds | 111 - board/qualcomm/dragonboard845c/Kconfig | 12 - board/qualcomm/qcs404-evb/Kconfig | 15 - board/qualcomm/qcs404-evb/qcs404-evb.c | 21 +- configs/dragonboard410c_chainloaded_defconfig | 72 + configs/dragonboard410c_defconfig | 6 +- configs/dragonboard820c_defconfig | 6 +- configs/dragonboard845c_defconfig | 29 - configs/qcom_defconfig | 71 + configs/qcs404evb_defconfig | 55 - configs/starqltechn_defconfig | 41 - doc/board/qualcomm/board.rst | 119 + doc/board/qualcomm/debugging.rst | 61 + doc/board/qualcomm/index.rst | 4 +- doc/board/qualcomm/qcs404.rst | 79 - doc/board/qualcomm/sdm845.rst | 162 - doc/device-tree-bindings/mmc/msm_sdhci.txt | 25 - doc/device-tree-bindings/usb/ehci-msm.txt | 10 - drivers/clk/qcom/clock-apq8016.c | 9 +- drivers/clk/qcom/clock-apq8096.c | 7 +- drivers/mmc/msm_sdhci.c | 69 +- drivers/phy/qcom/msm8916-usbh-phy.c | 2 +- drivers/pinctrl/qcom/pinctrl-apq8016.c | 2 +- drivers/serial/Kconfig | 8 + drivers/serial/serial_msm.c | 61 +- drivers/usb/dwc3/dwc3-generic.c | 12 + drivers/usb/host/ehci-msm.c | 2 +- include/configs/dragonboard845c.h | 20 - include/configs/qcom.h | 21 + include/configs/qcs404-evb.h | 20 - include/dt-bindings/arm/coresight-cti-dt.h | 37 + include/dt-bindings/clock/qcom,camcc-sdm845.h | 116 + include/dt-bindings/clock/qcom,dispcc-sdm845.h | 56 + include/dt-bindings/clock/qcom,gcc-msm8916.h | 179 + include/dt-bindings/clock/qcom,gcc-msm8996.h | 360 ++ include/dt-bindings/clock/qcom,gcc-qcs404.h | 4 + include/dt-bindings/clock/qcom,gpucc-sdm845.h | 24 + include/dt-bindings/clock/qcom,lpass-sdm845.h | 15 + include/dt-bindings/clock/qcom,mmcc-msm8996.h | 295 + include/dt-bindings/clock/qcom,rpmcc.h | 174 + include/dt-bindings/clock/qcom,rpmh.h | 37 + include/dt-bindings/clock/qcom,turingcc-qcs404.h | 15 + include/dt-bindings/clock/qcom,videocc-sdm845.h | 35 + include/dt-bindings/dma/qcom-gpi.h | 11 + include/dt-bindings/firmware/qcom,scm.h | 18 + include/dt-bindings/iio/qcom,spmi-vadc.h | 300 + include/dt-bindings/interconnect/qcom,msm8916.h | 100 + .../dt-bindings/interconnect/qcom,msm8996-cbf.h | 12 + include/dt-bindings/interconnect/qcom,msm8996.h | 163 + include/dt-bindings/interconnect/qcom,osm-l3.h | 15 + include/dt-bindings/interconnect/qcom,sdm845.h | 150 + include/dt-bindings/phy/phy-qcom-qusb2.h | 37 + include/dt-bindings/pinctrl/qcom,pmic-gpio.h | 164 + include/dt-bindings/power/qcom-rpmpd.h | 412 ++ include/dt-bindings/reset/qcom,gcc-msm8916.h | 100 + include/dt-bindings/reset/qcom,sdm845-aoss.h | 17 + include/dt-bindings/reset/qcom,sdm845-pdc.h | 22 + include/dt-bindings/soc/qcom,apr.h | 28 + include/dt-bindings/soc/qcom,rpmh-rsc.h | 14 + include/init.h | 11 + 104 files changed, 18987 insertions(+), 2063 deletions(-)
base-commit: 516584b4d50880cb5e2361e55f8c5b4fc6c35901
// Caleb (they/them)