From 999159a5381bff3bd6f688c5d20fbec9d8789e53 Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Tue, 22 Jan 2013 17:00:52 +0530 Subject: ARC: [DeviceTree] Basic support This is minimal infrastructure needed for devicetree work. It uses an a sample "skeleton" devicetree - embedded in kernel image - to print the board, manufacturer by parsing the top-level "compatible" string. As of now we don't need any additional "board" specific "machine_desc". TODO: support interpreting the command line as boot-loader passed dtb Signed-off-by: Vineet Gupta Cc: Arnd Bergmann Cc: Grant Likely Cc: devicetree-discuss@lists.ozlabs.org Cc: Rob Herring Cc: James Hogan Reviewed-by: Rob Herring Reviewed-by: James Hogan --- arch/arc/Kconfig | 9 ++++++ arch/arc/Makefile | 9 ++++++ arch/arc/boot/dts/Makefile | 13 +++++++++ arch/arc/boot/dts/skeleton.dts | 10 +++++++ arch/arc/boot/dts/skeleton.dtsi | 21 ++++++++++++++ arch/arc/include/asm/prom.h | 15 ++++++++++ arch/arc/include/asm/sections.h | 1 + arch/arc/kernel/Makefile | 1 + arch/arc/kernel/devtree.c | 64 +++++++++++++++++++++++++++++++++++++++++ arch/arc/kernel/setup.c | 9 ++++++ arch/arc/mm/init.c | 13 +++++++++ 11 files changed, 165 insertions(+) create mode 100644 arch/arc/boot/dts/Makefile create mode 100644 arch/arc/boot/dts/skeleton.dts create mode 100644 arch/arc/boot/dts/skeleton.dtsi create mode 100644 arch/arc/include/asm/prom.h create mode 100644 arch/arc/kernel/devtree.c diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index a3538493e353..76668579b543 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -24,8 +24,11 @@ config ARC select GENERIC_SMP_IDLE_THREAD select HAVE_GENERIC_HARDIRQS select HAVE_MEMBLOCK + select IRQ_DOMAIN select MODULES_USE_ELF_RELA select NO_BOOTMEM + select OF + select OF_EARLY_FLATTREE config SCHED_OMIT_FRAME_POINTER def_bool y @@ -320,6 +323,12 @@ config CMDLINE_UBOOT to it. kernel startup code will copy the string into cmdline buffer and also append CONFIG_CMDLINE. +config ARC_BUILTIN_DTB_NAME + string "Built in DTB" + help + Set the name of the DTB to embed in the vmlinux binary + Leaving it blank selects the minimal "skeleton" dtb + source "kernel/Kconfig.preempt" endmenu # "ARC Architecture Configuration" diff --git a/arch/arc/Makefile b/arch/arc/Makefile index 4d52a3bb68a0..29b5fcd9c4b6 100644 --- a/arch/arc/Makefile +++ b/arch/arc/Makefile @@ -83,6 +83,9 @@ head-y := arch/arc/kernel/head.o # See arch/arc/Kbuild for content of core part of the kernel core-y += arch/arc/ +# w/o this dtb won't embed into kernel binary +core-y += arch/arc/boot/dts/ + # w/o this ifneq, make ARCH=arc clean was crapping out ifneq ($(platform-y),) core-y += arch/arc/plat-$(PLATFORM)/ @@ -101,6 +104,12 @@ bootpImage: vmlinux uImage: vmlinux $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ +%.dtb %.dtb.S %.dtb.o: scripts + $(Q)$(MAKE) $(build)=$(boot)/dts $(boot)/dts/$@ + +dtbs: scripts + $(Q)$(MAKE) $(build)=$(boot)/dts dtbs + archclean: $(Q)$(MAKE) $(clean)=$(boot) diff --git a/arch/arc/boot/dts/Makefile b/arch/arc/boot/dts/Makefile new file mode 100644 index 000000000000..17dc7b8b05fa --- /dev/null +++ b/arch/arc/boot/dts/Makefile @@ -0,0 +1,13 @@ +# Built-in dtb +builtindtb-y := skeleton + +ifneq ($(CONFIG_ARC_BUILTIN_DTB_NAME),"") + builtindtb-y := $(patsubst "%",%,$(CONFIG_ARC_BUILTIN_DTB_NAME)) +endif + +obj-y += $(builtindtb-y).dtb.o +targets += $(builtindtb-y).dtb + +dtbs: $(addprefix $(obj)/, $(builtindtb-y).dtb) + +clean-files := *.dtb diff --git a/arch/arc/boot/dts/skeleton.dts b/arch/arc/boot/dts/skeleton.dts new file mode 100644 index 000000000000..25a84fb5b3dc --- /dev/null +++ b/arch/arc/boot/dts/skeleton.dts @@ -0,0 +1,10 @@ +/* + * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com) + * + * 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. + */ +/dts-v1/; + +/include/ "skeleton.dtsi" diff --git a/arch/arc/boot/dts/skeleton.dtsi b/arch/arc/boot/dts/skeleton.dtsi new file mode 100644 index 000000000000..9b357d802a10 --- /dev/null +++ b/arch/arc/boot/dts/skeleton.dtsi @@ -0,0 +1,21 @@ +/* + * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com) + * + * 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. + */ + +/* + * Skeleton device tree; the bare minimum needed to boot; just include and + * add a compatible value. + */ + +/ { + compatible = "snps,arc"; + #address-cells = <1>; + #size-cells = <1>; + chosen { }; + aliases { }; + memory { device_type = "memory"; reg = <0 0>; }; +}; diff --git a/arch/arc/include/asm/prom.h b/arch/arc/include/asm/prom.h new file mode 100644 index 000000000000..f54489bc4eca --- /dev/null +++ b/arch/arc/include/asm/prom.h @@ -0,0 +1,15 @@ +/* + * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com) + * + * 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. + */ + +#ifndef _ASM_ARC_PROM_H_ +#define _ASM_ARC_PROM_H_ + +#define HAVE_ARCH_DEVTREE_FIXUPS +extern int __init setup_machine_fdt(void *dt); + +#endif diff --git a/arch/arc/include/asm/sections.h b/arch/arc/include/asm/sections.h index fc15f2e1a12e..6fc1159dfefe 100644 --- a/arch/arc/include/asm/sections.h +++ b/arch/arc/include/asm/sections.h @@ -13,5 +13,6 @@ extern char _int_vec_base_lds[]; extern char __arc_dccm_base[]; +extern char __dtb_start[]; #endif diff --git a/arch/arc/kernel/Makefile b/arch/arc/kernel/Makefile index 6d834312f755..c9ec0662a4ec 100644 --- a/arch/arc/kernel/Makefile +++ b/arch/arc/kernel/Makefile @@ -7,6 +7,7 @@ obj-y := arcksyms.o setup.o irq.o time.o reset.o ptrace.o entry.o process.o obj-y += signal.o traps.o sys.o troubleshoot.o stacktrace.o clk.o +obj-y += devtree.o obj-$(CONFIG_ARC_FPU_SAVE_RESTORE) += fpu.o CFLAGS_fpu.o += -mdpfp diff --git a/arch/arc/kernel/devtree.c b/arch/arc/kernel/devtree.c new file mode 100644 index 000000000000..48e157efad15 --- /dev/null +++ b/arch/arc/kernel/devtree.c @@ -0,0 +1,64 @@ +/* + * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com) + * + * Based on reduced version of METAG + * + * 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. + */ + + +#include +#include +#include +#include +#include +#include + +/* called from unflatten_device_tree() to bootstrap devicetree itself */ +void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align) +{ + return __va(memblock_alloc(size, align)); +} + +/** + * setup_machine_fdt - Machine setup when an dtb was passed to the kernel + * @dt: virtual address pointer to dt blob + * + * If a dtb was passed to the kernel, then use it to choose the correct + * machine_desc and to setup the system. + */ +int __init setup_machine_fdt(void *dt) +{ + struct boot_param_header *devtree = dt; + unsigned long dt_root; + char *model, *compat; + char manufacturer[16]; + + /* check device tree validity */ + if (be32_to_cpu(devtree->magic) != OF_DT_HEADER) + return 1; + + /* Search the mdescs for the 'best' compatible value match */ + initial_boot_params = devtree; + dt_root = of_get_flat_dt_root(); + + /* compat = "," */ + compat = of_get_flat_dt_prop(dt_root, "compatible", NULL); + if (!compat) + compat = ""; + + model = strchr(compat, ','); + if (model) + model++; + + strlcpy(manufacturer, compat, model ? model - compat : strlen(compat)); + + pr_info("Board \"%s\" from %s (Manufacturer)\n", model, manufacturer); + + /* Retrieve various information from the /chosen node */ + of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line); + + return 0; +} diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c index 82ac20603398..27aebd6d9513 100644 --- a/arch/arc/kernel/setup.c +++ b/arch/arc/kernel/setup.c @@ -13,6 +13,8 @@ #include #include #include +#include +#include #include #include #include @@ -20,6 +22,7 @@ #include #include #include +#include #define FIX_PTR(x) __asm__ __volatile__(";" : "+r"(x)) @@ -57,6 +60,8 @@ void __init __attribute__((weak)) arc_platform_early_init(void) void __init setup_arch(char **cmdline_p) { + int rc; + #ifdef CONFIG_CMDLINE_UBOOT /* Make sure that a whitespace is inserted before */ strlcat(command_line, " ", sizeof(command_line)); @@ -71,6 +76,8 @@ void __init setup_arch(char **cmdline_p) strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE); *cmdline_p = command_line; + rc = setup_machine_fdt(__dtb_start); + /* To force early parsing of things like mem=xxx */ parse_early_param(); @@ -81,6 +88,8 @@ void __init setup_arch(char **cmdline_p) setup_arch_memory(); + unflatten_device_tree(); + /* Can be issue if someone passes cmd line arg "ro" * But that is unlikely so keeping it as it is */ diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c index 63da3478521f..682cf5740483 100644 --- a/arch/arc/mm/init.c +++ b/arch/arc/mm/init.c @@ -39,6 +39,11 @@ static int __init setup_mem_sz(char *str) } early_param("mem", setup_mem_sz); +void __init early_init_dt_add_memory_arch(u64 base, u64 size) +{ + pr_err("%s(%llx, %llx)\n", __func__, base, size); +} + /* * First memory setup routine called from setup_arch() * 1. setup swapper's mm @init_mm @@ -169,3 +174,11 @@ void __init free_initrd_mem(unsigned long start, unsigned long end) free_init_pages("initrd memory", start, end); } #endif + +#ifdef CONFIG_OF_FLATTREE +void __init early_init_dt_setup_initrd_arch(unsigned long start, + unsigned long end) +{ + pr_err("%s(%lx, %lx)\n", __func__, start, end); +} +#endif /* CONFIG_OF_FLATTREE */ -- cgit