I send a new patch with suggested change. Feel you free to edit the commit message. I have no copy left or other copyrights on my code. best regards Pascal 2018-06-05 21:54 GMT+02:00 Sam Ravnborg <sam@xxxxxxxxxxxx>: > Hi Pascal. > > On Tue, Jun 05, 2018 at 05:40:51PM +0000, Pascal Vizeli wrote: >> Origin by Jan Luebbe: >> http://lists.infradead.org/pipermail/barebox/2015-March/022674.html >> >> I rebase the patches and fix the resolve for __local_fixups__, they >> was wrong copy/ported from linux kernel. >> >> I merge the overlay code from oftree into own command: of_overlay >> >> Signed-off-by: Pascal Vizeli <pvizeli@xxxxxxxxxx> > > You left out the "Signed-off-by: Jan ..." > Is this because you fundamentally changed the patches, then please say so. > Otherwise add it. > > This comment from Jans changelog is missing: > This is based on Pantelis Antoniou's overlay support for the kernel. It > has been simplified by leaving out transaction support, locking and > other details required by the Linux DT support. > > Is this because the above info is no longer valid? > Otherwise include it. > > >> --- >> Documentation/user/devicetree.rst | 101 ++++++++- >> arch/sandbox/dts/Makefile | 5 +- >> arch/sandbox/dts/sandbox-overlay.dtso | 26 +++ >> arch/sandbox/dts/sandbox.dts | 6 + >> commands/Kconfig | 10 + >> commands/Makefile | 1 + >> commands/of_overlay.c | 106 +++++++++ >> drivers/of/Kconfig | 6 + >> drivers/of/Makefile | 1 + >> drivers/of/overlay.c | 234 +++++++++++++++++++ >> drivers/of/resolver.c | 314 ++++++++++++++++++++++++++ >> include/of.h | 71 ++++++ >> scripts/Makefile.lib | 5 +- >> 13 files changed, 882 insertions(+), 4 deletions(-) >> create mode 100644 arch/sandbox/dts/sandbox-overlay.dtso >> create mode 100644 commands/of_overlay.c >> create mode 100644 drivers/of/overlay.c >> create mode 100644 drivers/of/resolver.c >> >> diff --git a/Documentation/user/devicetree.rst b/Documentation/user/devicetree.rst >> index 17934d86e..8b7be4f5b 100644 >> --- a/Documentation/user/devicetree.rst >> +++ b/Documentation/user/devicetree.rst >> @@ -21,7 +21,7 @@ The internal devicetree >> ----------------------- >> >> The devicetree consulted by barebox plays a special role. It is referred to >> -as the "internal devicetree." The barebox devicetree commands work on this >> +as the "internal devicetree". The barebox devicetree commands work on this >> devicetree. The devicetree source (DTS) files are kept in sync with the kernel DTS >> files. As the FDT files are meant to be backward compatible, it should always be possible >> to start a kernel with the barebox internal devicetree. However, since the barebox >> @@ -83,3 +83,102 @@ you can exchange the internal devicetree during runtime using the >> >> oftree -f >> oftree -l /new/dtb >> + >> +Devicetree overlays >> +------------------- >> + >> +Since version 3.19, the Linux kernel supports applying "devicetree overlays" to >> +its loaded device tree. This can be used to inform the kernel about additional >> +non-discoverable devices after the system has booted, which is useful for modular >> +boards and FPGAs. The details of the overlay format are specified in the Linux >> +`kernel documentation <https://www.kernel.org/doc/Documentation/devicetree/overlay-notes.txt>`_ >> +and an updated DTC is required to compile the overlays. >> + >> +The use cases for overlays in barebox are a bit different: >> + >> +* some of the modular devices are needed to boot Linux to userspace, but barebox >> + can detect which module variant is connected >> +* one of several parallel or LVDS displays (which use timing data from devicetree) >> + can be connected to the SoC and should be used for boot messages >> +* a generic Linux (distribution) kernel should be booted on a modular >> + system and support additional hardware on modules >> + >> +barebox supports applying overlays in the internal devicetree was well using the >> +:ref:`command_oftree` command with option ``-o``: >> + >> +.. code-block:: none >> + >> + $ ./barebox -d arch/sandbox/dts/sandbox.dtb -i arch/sandbox/dts/sandbox-overlay.dtbo >> + add fd0 backed by file arch/sandbox/dts/sandbox-overlay.dtbo >> + >> + barebox 2015.02.0 #26 Wed Mar 4 09:41:19 CET 2015 >> + ... >> + barebox@barebox sandbox:/ of_dump >> + ... >> + dummy@0 { >> + status = "disabled"; >> + linux,phandle = <0x1>; >> + phandle = <0x1>; >> + }; >> + dummy@1 { >> + status = "disabled"; >> + linux,phandle = <0x2>; >> + phandle = <0x2>; >> + }; >> + __symbols__ { >> + dummy0 = "/dummy@0"; >> + dummy1 = "/dummy@1"; >> + }; >> + ... >> + barebox@barebox sandbox:/ of_dump -f /dev/fd0 >> + { >> + fragment@0 { >> + target = <0xdeadbeef>; >> + __overlay__ { >> + status = "okay"; >> + child { >> + compatible = "barebox,dummy"; >> + }; >> + }; >> + }; >> + fragment@1 { >> + target = <0xdeadbeef>; >> + __overlay__ { >> + status = "okay"; >> + child { >> + compatible = "barebox,dummy"; >> + }; >> + }; >> + }; >> + __fixups__ { >> + dummy0 = "/fragment@0:target:0"; >> + dummy1 = "/fragment@1:target:0"; >> + }; >> + }; >> + barebox@barebox sandbox:/ of_overlay /dev/fd0 >> + barebox@barebox sandbox:/ of_dump >> + ... >> + dummy@0 { >> + linux,phandle = <0x1>; >> + phandle = <0x1>; >> + status = "okay"; >> + child { >> + compatible = "barebox,dummy"; >> + }; >> + }; >> + dummy@1 { >> + linux,phandle = <0x2>; >> + phandle = <0x2>; >> + status = "okay"; >> + child { >> + compatible = "barebox,dummy"; >> + }; >> + }; >> + __symbols__ { >> + dummy0 = "/dummy@0"; >> + dummy1 = "/dummy@1"; >> + }; >> + ... >> + >> +If you need to use a different base devicetree instead of the one compiled into >> +barebox, it needs to be replaced as described in the previous section. >> diff --git a/arch/sandbox/dts/Makefile b/arch/sandbox/dts/Makefile >> index 6f6838857..ede219e6f 100644 >> --- a/arch/sandbox/dts/Makefile >> +++ b/arch/sandbox/dts/Makefile >> @@ -1,6 +1,7 @@ >> ifeq ($(CONFIG_OFTREE),y) >> dtb-y += \ >> - sandbox.dtb >> + sandbox.dtb \ >> + sandbox-overlay.dtbo >> endif >> >> # just to build a built-in.o. Otherwise compilation fails when no devicetree is >> @@ -8,4 +9,4 @@ endif >> obj- += dummy.o >> >> always := $(dtb-y) >> -clean-files := *.dtb *.dtb.S .*.dtc .*.pre .*.dts >> +clean-files := *.dtb *.dtb.S .*.dtc .*.pre .*.dts *.dtbo >> diff --git a/arch/sandbox/dts/sandbox-overlay.dtso b/arch/sandbox/dts/sandbox-overlay.dtso >> new file mode 100644 >> index 000000000..f9ced04ca >> --- /dev/null >> +++ b/arch/sandbox/dts/sandbox-overlay.dtso >> @@ -0,0 +1,26 @@ >> +/dts-v1/; >> + >> +/plugin/; >> + >> +/ { >> + fragment@0 { >> + target = <&dummy0>; >> + __overlay__ { >> + status = "okay"; >> + child { >> + compatible = "barebox,dummy"; >> + }; >> + }; >> + }; >> + >> + fragment@1 { >> + target = <&dummy1>; >> + __overlay__ { >> + status = "okay"; >> + child { >> + compatible = "barebox,dummy"; >> + }; >> + }; >> + }; >> +}; >> + >> diff --git a/arch/sandbox/dts/sandbox.dts b/arch/sandbox/dts/sandbox.dts >> index 2595aa13f..1b99a4960 100644 >> --- a/arch/sandbox/dts/sandbox.dts >> +++ b/arch/sandbox/dts/sandbox.dts >> @@ -3,5 +3,11 @@ >> #include "skeleton.dtsi" >> >> / { >> + dummy0: dummy@0 { >> + status = "disabled"; >> + }; >> >> + dummy1: dummy@1 { >> + status = "disabled"; >> + }; >> }; >> diff --git a/commands/Kconfig b/commands/Kconfig >> index 951a86963..22d131da3 100644 >> --- a/commands/Kconfig >> +++ b/commands/Kconfig >> @@ -2033,6 +2033,16 @@ config CMD_OF_NODE >> -c create a new node >> -d delete a node >> >> +config CMD_OF_OVERLAY >> + tristate >> + select OFTREE >> + select OFTREE_OVERLAY >> + prompt "of_overlay" >> + help >> + Apply a dtb overlay to internal device tree >> + >> + Usage: of_overlay DTBO >> + >> config CMD_OF_PROPERTY >> tristate >> select OFTREE >> diff --git a/commands/Makefile b/commands/Makefile >> index eb4796389..f404338fa 100644 >> --- a/commands/Makefile >> +++ b/commands/Makefile >> @@ -75,6 +75,7 @@ obj-$(CONFIG_CMD_USB) += usb.o >> obj-$(CONFIG_CMD_TIME) += time.o >> obj-$(CONFIG_CMD_OFTREE) += oftree.o >> obj-$(CONFIG_CMD_OF_PROPERTY) += of_property.o >> +obj-$(CONFIG_CMD_OF_OVERLAY) += of_overlay.o >> obj-$(CONFIG_CMD_OF_NODE) += of_node.o >> obj-$(CONFIG_CMD_OF_DUMP) += of_dump.o >> obj-$(CONFIG_CMD_OF_DISPLAY_TIMINGS) += of_display_timings.o >> diff --git a/commands/of_overlay.c b/commands/of_overlay.c >> new file mode 100644 >> index 000000000..6c74c72bc >> --- /dev/null >> +++ b/commands/of_overlay.c >> @@ -0,0 +1,106 @@ >> +/* >> + * of_overlay.c - device tree overlay command support >> + * >> + * Copyright (c) 2018 Pascal Vizeli <pvizeli@xxxxxxxxxx>, Hass.io > > Most of the code was made by Jan, > so you should keep his Copyright. > >> + * >> + * See file CREDITS for list of people who contributed to this >> + * project. >> + * >> + * This program is free software; you can redistribute it and/or modify >> + * it under the terms of the GNU General Public License version 2 >> + * as published by the Free Software Foundation. >> + * >> + * This program is distributed in the hope that it will be useful, >> + * but WITHOUT ANY WARRANTY; without even the implied warranty of >> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the >> + * GNU General Public License for more details. >> + * >> + */ >> + >> +#include <common.h> >> +#include <environment.h> >> +#include <fdt.h> >> +#include <libfile.h> >> +#include <of.h> >> +#include <command.h> >> +#include <fs.h> >> +#include <malloc.h> >> +#include <linux/ctype.h> >> +#include <linux/err.h> >> +#include <asm/byteorder.h> >> +#include <errno.h> >> +#include <getopt.h> >> +#include <init.h> >> +#include <fcntl.h> >> +#include <complete.h> >> + >> +static int do_of_overlay(int argc, char *argv[]) >> +{ >> + struct fdt_header *fdt = NULL; >> + size_t size; >> + char *filename = NULL; >> + int ret = 0, ovinfo_cnt; >> + struct device_node *overlay = NULL, *root; >> + struct of_overlay_info *ovinfo; >> + >> + if (argc != 2 || !IS_ENABLED(CONFIG_OFTREE_OVERLAY)) >> + return COMMAND_ERROR_USAGE; > > CONFIG_OFTREE_OVERLAY is "select" when adding this command, > so this check should not be needed. > > >> + >> + filename = argv[1]; >> + >> + root = of_get_root_node(); >> + if (!root) { >> + printf("no oftree loaded\n"); >> + goto out; >> + } > This will result in return 0 - which indicate that there was no error. > Should be return 1 or something > >> + >> + fdt = read_file(filename, &size); >> + if (!fdt) { >> + printf("unable to read %s\n", filename); >> + return 1; >> + } > Like here. > >> + >> + overlay = of_unflatten_dtb(fdt); >> + free(fdt); >> + >> + if (IS_ERR(overlay)) { >> + printf("parse oftree: %s\n", strerror(-ret)); >> + return PTR_ERR(overlay); >> + } >> + >> + ret = of_resolve(overlay); > of_resolve return a negative error in case of errors. >> + if (ret) { >> + printf("resolve oftree overlay: %s\n", strerror(-ret)); >> + goto out; > So here we will return a negative number from this command. >> + } > >> + >> + ret = of_build_overlay_info(overlay, &ovinfo_cnt, &ovinfo); >> + if (ret) { >> + printf("prepare oftree overlay: %s\n", strerror(-ret)); >> + goto out; >> + } > Likewise > >> + >> + ret = of_overlay(ovinfo_cnt, ovinfo); > of_overlay may return a positive or negative number >> + if (ret) { >> + printf("apply oftree overlay: %s\n", strerror(-ret)); > So this may not print what you want. > >> + goto out; >> + } >> + >> + ret = 0; >> + >> +out: >> + of_delete_node(overlay); >> + return ret; >> +} >> + >> +BAREBOX_CMD_HELP_START(of_overlay) >> +BAREBOX_CMD_HELP_TEXT("Apply a dtb overlay to internal device tree") >> +BAREBOX_CMD_HELP_END >> + >> +BAREBOX_CMD_START(of_overlay) >> + .cmd = do_of_overlay, >> + BAREBOX_CMD_DESC("Apply a dtb overlay") >> + BAREBOX_CMD_OPTS("DTBO") >> + BAREBOX_CMD_GROUP(CMD_GRP_MISC) >> + BAREBOX_CMD_HELP(cmd_of_overlay_help) >> +BAREBOX_CMD_END > > > Sam _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox
