Hi Mark, On Mon, 20 Sept 2021 at 02:49, Mark Kettenis <mark.kette...@xs4all.nl> wrote: > > > From: Simon Glass <s...@chromium.org> > > Date: Sun, 19 Sep 2021 21:15:57 -0600 > > > > Hi Mark, > > > > On Sat, 18 Sept 2021 at 07:55, Mark Kettenis <kette...@openbsd.org> wrote: > > > > > > Add support for Apple's M1 SoC that is used in "Apple Silicon" > > > Macs. This builds a basic U-Boot that can be used as a payload > > > for the m1n1 boot loader being developed by the Asahi Linux > > > project. > > > > > > Signed-off-by: Mark Kettenis <kette...@openbsd.org> > > > --- > > > arch/arm/Kconfig | 22 ++++ > > > arch/arm/Makefile | 1 + > > > arch/arm/mach-apple/Kconfig | 18 ++++ > > > arch/arm/mach-apple/Makefile | 4 + > > > arch/arm/mach-apple/board.c | 158 ++++++++++++++++++++++++++++ > > > arch/arm/mach-apple/lowlevel_init.S | 16 +++ > > > configs/apple_m1_defconfig | 14 +++ > > > include/configs/apple.h | 38 +++++++ > > > 8 files changed, 271 insertions(+) > > > create mode 100644 arch/arm/mach-apple/Kconfig > > > create mode 100644 arch/arm/mach-apple/Makefile > > > create mode 100644 arch/arm/mach-apple/board.c > > > create mode 100644 arch/arm/mach-apple/lowlevel_init.S > > > create mode 100644 configs/apple_m1_defconfig > > > create mode 100644 include/configs/apple.h > > > > > > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig > > > index b5bd3284cd..7cdea1f615 100644 > > > --- a/arch/arm/Kconfig > > > +++ b/arch/arm/Kconfig > > > @@ -895,6 +895,26 @@ config ARCH_NEXELL > > > select DM > > > select GPIO_EXTRA_HEADER > > > > > > +config ARCH_APPLE > > > + bool "Apple SoCs" > > > + select ARM64 > > > + select LINUX_KERNEL_IMAGE_HEADER > > > + select POSITION_INDEPENDENT > > > + select BLK > > > + select DM > > > + select DM_KEYBOARD > > > + select DM_SERIAL > > > + select DM_USB > > > + select DM_VIDEO > > > + select CMD_USB > > > + select MISC > > > + select OF_CONTROL > > > + select OF_BOARD > > > + select USB > > > + imply CMD_DM > > > + imply CMD_GPT > > > + imply DISTRO_DEFAULTS > > > > Suggest sorting these > > As in sort all the selects alphabetically and sort all the implies > alphabetically seperately?
I suppose so. > > Does my use of impy here even make sense? It allows people to disable it, whereas select does not. It looks OK to me. > > This whole Kconfig stuff is a bit alien to me and I must say that it > isn't obvious what "best-practice" is in this area... We try to avoid select so only use it if it really cannot build/run without that feature. From what I can tell you have done that. I know this is a different project, but there are some ideas here: https://docs.zephyrproject.org/1.14.0/guides/kconfig/index.html [..] > > > +int dram_init(void) > > > +{ > > > + int index, node, ret; > > > + fdt_addr_t base; > > > + fdt_size_t size; > > > + > > > + ret = fdtdec_setup_mem_size_base(); > > > + if (ret) > > > + return ret; > > > + > > > + /* Update RAM mapping. */ > > > > Do you want the period at the end of that? > > Given that Bin brought up the same thing, I gather that not having a > full stop at the end of single-line comments is preferred? Yes, the periods just clutter things and people start adding them only when it is a valid sentence, etc. Best to just leave them out. > > > > + index = ARRAY_SIZE(apple_mem_map) - 3; > > > + apple_mem_map[index].virt = gd->ram_base; > > > + apple_mem_map[index].phys = gd->ram_base; > > > + apple_mem_map[index].size = gd->ram_size; > > > + > > > + node = fdt_path_offset(gd->fdt_blob, "/chosen/framebuffer"); > > > > Can you use the ofnode interface here and below? > > I can try... Something like: ofnode node; node = ofnode_path("/chosen/framebuffer"); then use ofnode_get_addr_size() > > > > + if (node < 0) > > > + return 0; > > > + > > > + base = fdtdec_get_addr_size(gd->fdt_blob, node, "reg", &size); > > > + if (base == FDT_ADDR_T_NONE) > > > + return 0; > > > + > > > + /* Add framebuffer mapping. */ > > > + index = ARRAY_SIZE(apple_mem_map) - 2; > > > + apple_mem_map[index].virt = base; > > > + apple_mem_map[index].phys = base; > > > + apple_mem_map[index].size = size; > > > + apple_mem_map[index].attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL_NC) | > > > + PTE_BLOCK_INNER_SHARE | PTE_BLOCK_PXN | PTE_BLOCK_UXN; > > > + > > > + return 0; > > > +} [..] > > > diff --git a/arch/arm/mach-apple/lowlevel_init.S > > > b/arch/arm/mach-apple/lowlevel_init.S > > > new file mode 100644 > > > index 0000000000..0f5313163e > > > --- /dev/null > > > +++ b/arch/arm/mach-apple/lowlevel_init.S > > > @@ -0,0 +1,16 @@ > > > +/* SPDX-License-Identifier: GPL-2.0+ */ > > > +/* > > > + * (C) Copyright 2021 Mark Kettenis <kette...@openbsd.org> > > > + */ > > > + > > > +.align 8 > > > +.global fw_dtb_pointer > > > +fw_dtb_pointer: > > > + .quad 0 > > > + > > > +.global save_boot_params > > > +save_boot_params: > > > + adr x1, fw_dtb_pointer > > > > could use a comment as to where this is set up. Previous-stage > > firmware, I suppose? > > Yes. I'm basically making U-Boot look like a Linux kernel, and m1n1 > passes the DT in x1 just like the Linux kernel expects. > > I suspect using CONFIG_OF_PRIOR_STAGE would make it more obvious what > is happening here. But (a) I didn't know that existed and (b) we > discussed removing that option in the near future. That sounds right to me, but a comment would help. Regards, Simon