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-rw-r--r--arch/arc/kernel/devtree.c123
1 files changed, 123 insertions, 0 deletions
diff --git a/arch/arc/kernel/devtree.c b/arch/arc/kernel/devtree.c
new file mode 100644
index 0000000..bdee3a8
--- /dev/null
+++ b/arch/arc/kernel/devtree.c
@@ -0,0 +1,123 @@
+/*
+ * 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>
+#include <asm/clk.h>
+#include <asm/mach_desc.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.
+ */
+struct machine_desc * __init setup_machine_fdt(void *dt)
+{
+ struct boot_param_header *devtree = dt;
+ struct machine_desc *mdesc = NULL, *mdesc_best = NULL;
+ unsigned int score, mdesc_score = ~1;
+ unsigned long dt_root;
+ const char *model, *compat;
+ void *clk;
+ char manufacturer[16];
+ unsigned long len;
+
+ /* check device tree validity */
+ if (be32_to_cpu(devtree->magic) != OF_DT_HEADER)
+ return NULL;
+
+ initial_boot_params = devtree;
+ dt_root = of_get_flat_dt_root();
+
+ /*
+ * The kernel could be multi-platform enabled, thus could have many
+ * "baked-in" machine descriptors. Search thru all for the best
+ * "compatible" string match.
+ */
+ 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;
+
+ pr_err("\n unrecognized device tree list:\n[ ");
+
+ prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
+ if (prop) {
+ while (size > 0) {
+ printk("'%s' ", prop);
+ size -= strlen(prop) + 1;
+ prop += strlen(prop) + 1;
+ }
+ }
+ printk("]\n\n");
+
+ machine_halt();
+ }
+
+ /* compat = "<manufacturer>,<model>" */
+ compat = mdesc_best->dt_compat[0];
+
+ 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);
+
+ /* 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);
+
+ clk = of_get_flat_dt_prop(dt_root, "clock-frequency", &len);
+ if (clk)
+ arc_set_core_freq(of_read_ulong(clk, len/4));
+
+ return mdesc_best;
+}
+
+/*
+ * Copy the flattened DT out of .init since unflattening doesn't copy strings
+ * and the normal DT APIs refs them from orig flat DT
+ */
+void __init copy_devtree(void)
+{
+ void *alloc = early_init_dt_alloc_memory_arch(
+ be32_to_cpu(initial_boot_params->totalsize), 64);
+ if (alloc) {
+ memcpy(alloc, initial_boot_params,
+ be32_to_cpu(initial_boot_params->totalsize));
+ initial_boot_params = alloc;
+ }
+}