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 <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Rob Herring <rob.herring@calxeda.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
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
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"
# 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)/
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)
--- /dev/null
+# 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)/, $(builtindtb-y).dtb)
+
+clean-files := *.dtb
--- /dev/null
+/*
+ * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+/dts-v1/;
+
+/include/ "skeleton.dtsi"
--- /dev/null
+/*
+ * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/*
+ * Skeleton device tree; the bare minimum needed to boot; just include and
+ * add a compatible value.
+ */
+
+/ {
+ compatible = "snps,arc";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ chosen { };
+ aliases { };
+ memory { device_type = "memory"; reg = <0 0>; };
+};
--- /dev/null
+/*
+ * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_ARC_PROM_H_
+#define _ASM_ARC_PROM_H_
+
+#define HAVE_ARCH_DEVTREE_FIXUPS
+extern int __init setup_machine_fdt(void *dt);
+
+#endif
extern char _int_vec_base_lds[];
extern char __arc_dccm_base[];
+extern char __dtb_start[];
#endif
obj-y := arcksyms.o setup.o irq.o time.o reset.o ptrace.o entry.o process.o
obj-y += signal.o traps.o sys.o troubleshoot.o stacktrace.o clk.o
+obj-y += devtree.o
obj-$(CONFIG_ARC_FPU_SAVE_RESTORE) += fpu.o
CFLAGS_fpu.o += -mdpfp
--- /dev/null
+/*
+ * 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 <linux/init.h>
+#include <linux/reboot.h>
+#include <linux/memblock.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <asm/prom.h>
+
+/* 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 = "<manufacturer>,<model>" */
+ compat = of_get_flat_dt_prop(dt_root, "compatible", NULL);
+ if (!compat)
+ compat = "<unknown>";
+
+ 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;
+}
#include <linux/console.h>
#include <linux/module.h>
#include <linux/cpu.h>
+#include <linux/of_fdt.h>
+#include <asm/sections.h>
#include <asm/arcregs.h>
#include <asm/tlb.h>
#include <asm/cache.h>
#include <asm/page.h>
#include <asm/irq.h>
#include <asm/arcregs.h>
+#include <asm/prom.h>
#define FIX_PTR(x) __asm__ __volatile__(";" : "+r"(x))
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));
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();
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
*/
}
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
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 */
projects / firefly-linux-kernel-4.4.55.git / commitdiff