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-rw-r--r--arch/arm/kernel/devtree.c145
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);