Hi,
this v4 has several small improvements over v3, addressing all the comments received. No major changes.
This patchset aims at solving a long-standing issue in the ZynqMP users community: loading a PMU firmware configuration object when U-Boot SPL is used.
The Platform Management Unit (PMU) needs a configuration object (cfg obj) to know how to operate the SoC. When using the "Xilinx workflow", the Xilinx FSBL (First Stage Bootloader) has the SPL role. FSBL has a built-in cfg obj and passes it to the PMUFW at runtime before jumping to U-Boot proper.
This is just not implemented in the U-Boot code. The best workaround for U-Boot SPL users is to patch [0] the PMUFW itself to have the cfg obj built-in and self-load it. This approach has some drawbacks: among others, it forces to use a different PMUFW binary for each hardware and hardware configuation. It also makes it impossible to change the configuration after boot.
The first patch fills the gap by allowing U-Boot SPL to load the cfg obj firmware at runtime. It adds a Kconfig string option to point to the cfg obj in the form of a binary blob. If the option is non-empty, code is enabled to link that file in U-Boot SPL and send the configuration to PMUFW.
Patch 2 adds a tool to convert the cfg obj C file (as produced by the Xilinx XSDK proprietary tool) in a binary blob suitable for loading. As suggested by Mike Looijmans it has been implemented as a Python script to make it easily usable.
These patches are tested on the UltraZed EV board, on u-boot/master and microblaze/master, using the defconfig I submitted a few days ago [1].
Future work on this topic include moving the PMU IPC code to a mailbox uclass driver and adding a command in U-Boot proper to load a config object blob (e.g. from a file based on a script).
Many thanks to Michal Simek for his many suggestions on how to improve this work.
[0] https://github.com/topic-embedded-products/meta-topic/blob/master/recipes-bs... [1] https://lists.denx.de/pipermail/u-boot/2019-May/368957.html RFCv1: https://lists.denx.de/pipermail/u-boot/2019-February/360450.html RFCv2: https://lists.denx.de/pipermail/u-boot/2019-March/362464.html v3: https://lists.denx.de/pipermail/u-boot/2019-April/365410.html
Luca
Luca Ceresoli (2): arm64: zynqmp: spl: install a PMU firmware config object at runtime arm64: zynqmp: add tool to convert PMU config object .c to binary
arch/arm/mach-zynqmp/Kconfig | 18 ++ arch/arm/mach-zynqmp/Makefile | 4 + arch/arm/mach-zynqmp/include/mach/sys_proto.h | 2 + arch/arm/mach-zynqmp/pmu_ipc.c | 112 +++++++ board/xilinx/zynqmp/Makefile | 5 + board/xilinx/zynqmp/pm_cfg_obj.S | 17 + board/xilinx/zynqmp/pm_cfg_obj.h | 9 + board/xilinx/zynqmp/zynqmp.c | 9 + tools/zynqmp_pm_cfg_obj_convert.py | 302 ++++++++++++++++++ 9 files changed, 478 insertions(+) create mode 100644 arch/arm/mach-zynqmp/pmu_ipc.c create mode 100644 board/xilinx/zynqmp/pm_cfg_obj.S create mode 100644 board/xilinx/zynqmp/pm_cfg_obj.h create mode 100755 tools/zynqmp_pm_cfg_obj_convert.py