diff options
Diffstat (limited to 'arch/arm/kernel/devtree.c')
| -rw-r--r-- | arch/arm/kernel/devtree.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c new file mode 100644 index 00000000000..a701e4226a6 --- /dev/null +++ b/arch/arm/kernel/devtree.c @@ -0,0 +1,145 @@ +/* + * linux/arch/arm/kernel/devtree.c + * + * Copyright (C) 2009 Canonical Ltd. <jeremy.kerr@canonical.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. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/bootmem.h> +#include <linux/memblock.h> +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> + +#include <asm/setup.h> +#include <asm/page.h> +#include <asm/mach/arch.h> +#include <asm/mach-types.h> + +void __init early_init_dt_add_memory_arch(u64 base, u64 size) +{ + arm_add_memory(base, size); +} + +void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align) +{ + return alloc_bootmem_align(size, align); +} + +void __init arm_dt_memblock_reserve(void) +{ + u64 *reserve_map, base, size; + + if (!initial_boot_params) + return; + + /* Reserve the dtb region */ + memblock_reserve(virt_to_phys(initial_boot_params), + be32_to_cpu(initial_boot_params->totalsize)); + + /* + * Process the reserve map. This will probably overlap the initrd + * and dtb locations which are already reserved, but overlaping + * doesn't hurt anything + */ + reserve_map = ((void*)initial_boot_params) + + be32_to_cpu(initial_boot_params->off_mem_rsvmap); + while (1) { + base = be64_to_cpup(reserve_map++); + size = be64_to_cpup(reserve_map++); + if (!size) + break; + memblock_reserve(base, size); + } +} + +/** + * setup_machine_fdt - Machine setup when an dtb was passed to the kernel + * @dt_phys: physical address of dt blob + * + * If a dtb was passed to the kernel in r2, then use it to choose the + * correct machine_desc and to setup the system. + */ +struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys) +{ + struct boot_param_header *devtree; + struct machine_desc *mdesc, *mdesc_best = NULL; + unsigned int score, mdesc_score = ~1; + unsigned long dt_root; + const char *model; + + devtree = phys_to_virt(dt_phys); + + /* check device tree validity */ + if (be32_to_cpu(devtree->magic) != OF_DT_HEADER) + return NULL; + + /* Search the mdescs for the 'best' compatible value match */ + initial_boot_params = devtree; + dt_root = of_get_flat_dt_root(); + for_each_machine_desc(mdesc) { + score = of_flat_dt_match(dt_root, mdesc->dt_compat); + if (score > 0 && score < mdesc_score) { + mdesc_best = mdesc; + mdesc_score = score; + } + } + if (!mdesc_best) { + const char *prop; + long size; + + early_print("\nError: unrecognized/unsupported " + "device tree compatible list:\n[ "); + + prop = of_get_flat_dt_prop(dt_root, "compatible", &size); + while (size > 0) { + early_print("'%s' ", prop); + size -= strlen(prop) + 1; + prop += strlen(prop) + 1; + } + early_print("]\n\n"); + + dump_machine_table(); /* does not return */ + } + + model = of_get_flat_dt_prop(dt_root, "model", NULL); + if (!model) + model = of_get_flat_dt_prop(dt_root, "compatible", NULL); + if (!model) + model = "<unknown>"; + pr_info("Machine: %s, model: %s\n", mdesc_best->name, model); + + /* Retrieve various information from the /chosen node */ + of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line); + /* Initialize {size,address}-cells info */ + of_scan_flat_dt(early_init_dt_scan_root, NULL); + /* Setup memory, calling early_init_dt_add_memory_arch */ + of_scan_flat_dt(early_init_dt_scan_memory, NULL); + + /* Change machine number to match the mdesc we're using */ + __machine_arch_type = mdesc_best->nr; + + return mdesc_best; +} + +/** + * irq_create_of_mapping - Hook to resolve OF irq specifier into a Linux irq# + * + * Currently the mapping mechanism is trivial; simple flat hwirq numbers are + * mapped 1:1 onto Linux irq numbers. Cascaded irq controllers are not + * supported. + */ +unsigned int irq_create_of_mapping(struct device_node *controller, + const u32 *intspec, unsigned int intsize) +{ + return intspec[0]; +} +EXPORT_SYMBOL_GPL(irq_create_of_mapping); |