On 01/24/2013 04:50 AM, Vineet Gupta wrote: > 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@xxxxxxxxxxxx> > Cc: Arnd Bergmann <arnd@xxxxxxxx> > Cc: Grant Likely <grant.likely@xxxxxxxxxxxx> > Cc: devicetree-discuss@xxxxxxxxxxxxxxxx > Cc: Rob Herring <rob.herring@xxxxxxxxxxx> One minor thing below, otherwise: Reviewed-by: Rob Herring <rob.herring@xxxxxxxxxxx> > diff --git a/arch/arc/kernel/devtree.c b/arch/arc/kernel/devtree.c > new file mode 100644 > index 0000000..229f78e > --- /dev/null > +++ b/arch/arc/kernel/devtree.c > @@ -0,0 +1,69 @@ > +/* > + * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com) > + * > + * Based on highly stipped down 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/export.h> > +#include <linux/errno.h> Is this include needed? > +#include <linux/types.h> > +#include <linux/reboot.h> And this? > +#include <linux/memblock.h> > +#include <linux/of.h> > +#include <linux/of_fdt.h> > +#include <linux/of_irq.h> And this? > +#include <linux/of_platform.h> And this? > +#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; > +} > diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c > index 82ac206..27aebd6 100644 > --- a/arch/arc/kernel/setup.c > +++ b/arch/arc/kernel/setup.c > @@ -13,6 +13,8 @@ > #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> > @@ -20,6 +22,7 @@ > #include <asm/page.h> > #include <asm/irq.h> > #include <asm/arcregs.h> > +#include <asm/prom.h> > > #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 63da347..682cf57 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 */ > -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html