--- /dev/null
+/*
+ * Device Tree
+ *
+ * Copyright (C) 2012 Citrix Systems, Inc.
+ *
+ * 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 <xen/config.h>
+#include <xen/types.h>
+#include <xen/init.h>
+#include <xen/device_tree.h>
+#include <xen/kernel.h>
+#include <xen/lib.h>
+#include <xen/mm.h>
+#include <xen/stdarg.h>
+#include <xen/string.h>
+#include <asm/early_printk.h>
+
+#include <libfdt.h>
+
+struct dt_early_info __initdata early_info;
+
+static void __init get_val(const u32 **cell, u32 cells, u64 *val)
+{
+ *val = 0;
+
+ while (cells--) {
+ *val <<= 32;
+ *val |= fdt32_to_cpu(*(*cell)++);
+ }
+}
+
+static void __init get_register(const u32 **cell, u32 address_cells, u32 size_cells,
+ u64 *start, u64 *size)
+{
+ get_val(cell, address_cells, start);
+ get_val(cell, size_cells, size);
+}
+
+static u32 __init prop_by_name_u32(const void *fdt, int node, const char *prop_name)
+{
+ const struct fdt_property *prop;
+
+ prop = fdt_get_property(fdt, node, prop_name, NULL);
+ if (!prop || prop->len < sizeof(u32))
+ return 0; /* default to 0 */
+
+ return fdt32_to_cpu(*(uint32_t*)prop->data);
+}
+
+static void __init process_memory_node(const void *fdt, int node,
+ u32 address_cells, u32 size_cells)
+{
+ const struct fdt_property *prop;
+ size_t reg_cells;
+ int i;
+ int banks;
+ const u32 *cell;
+ paddr_t start, size;
+
+ if (address_cells < 1 || size_cells < 1) {
+ early_printk("fdt: node `%s': invalid #address-cells or #size-cells",
+ fdt_get_name(fdt, node, NULL));
+ return;
+ }
+
+ prop = fdt_get_property(fdt, node, "reg", NULL);
+ if (!prop) {
+ early_printk("fdt: node `%s': missing `reg' property\n",
+ fdt_get_name(fdt, node, NULL));
+ return;
+ }
+
+ cell = (const u32 *)prop->data;
+ reg_cells = address_cells + size_cells;
+ banks = fdt32_to_cpu(prop->len) / (reg_cells * sizeof(u32));
+
+ for (i = 0; i < banks && early_info.mem.nr_banks < NR_MEM_BANKS; i++) {
+ get_register(&cell, address_cells, size_cells, &start, &size);
+ early_info.mem.bank[early_info.mem.nr_banks].start = start;
+ early_info.mem.bank[early_info.mem.nr_banks].size = size;
+ early_info.mem.nr_banks++;
+ }
+}
+
+#define MAX_DEPTH 16
+
+static void __init early_scan(const void *fdt)
+{
+ int node;
+ int depth;
+ const char *name;
+ u32 address_cells[MAX_DEPTH];
+ u32 size_cells[MAX_DEPTH];
+
+ for (node = 0; depth >= 0; node = fdt_next_node(fdt, node, &depth)) {
+ name = fdt_get_name(fdt, node, NULL);
+
+ if (depth >= MAX_DEPTH) {
+ early_printk("fdt: node '%s': nested too deep\n",
+ fdt_get_name(fdt, node, NULL));
+ continue;
+ }
+
+ address_cells[depth] = prop_by_name_u32(fdt, node, "#address-cells");
+ size_cells[depth] = prop_by_name_u32(fdt, node, "#size-cells");
+
+ if (strncmp(name, "memory", 6) == 0)
+ process_memory_node(fdt, node, address_cells[depth-1], size_cells[depth-1]);
+ }
+}
+
+static void __init early_print_info(void)
+{
+ struct dt_mem_info *mi = &early_info.mem;
+ int i;
+
+ for (i = 0; i < mi->nr_banks; i++)
+ early_printk("RAM: %016llx - %016llx\n",
+ mi->bank[i].start, mi->bank[i].start + mi->bank[i].size - 1);
+}
+
+/**
+ * device_tree_early_init - initialize early info from a DTB
+ * @fdt: flattened device tree binary
+ */
+void __init device_tree_early_init(const void *fdt)
+{
+ int ret;
+
+ ret = fdt_check_header(fdt);
+ if (ret < 0)
+ early_panic("No valid device tree\n");
+
+ early_scan(fdt);
+ early_print_info();
+}
+
+/**
+ * device_tree_get_xen_paddr - get physical address to relocate Xen to
+ *
+ * Xen is relocated to the top of RAM and aligned to a XEN_PADDR_ALIGN
+ * boundary.
+ */
+paddr_t __init device_tree_get_xen_paddr(void)
+{
+ struct dt_mem_info *mi = &early_info.mem;
+ paddr_t min_size;
+ paddr_t paddr = 0, t;
+ int i;
+
+ min_size = (_end - _start + (XEN_PADDR_ALIGN-1)) & ~(XEN_PADDR_ALIGN-1);
+
+ /* Find the highest bank with enough space. */
+ for (i = 0; i < mi->nr_banks; i++) {
+ if (mi->bank[i].size >= min_size) {
+ t = mi->bank[i].start + mi->bank[i].size - min_size;
+ if (t > paddr)
+ paddr = t;
+ }
+ }
+
+ if (!paddr)
+ early_panic("Not enough memory to relocate Xen\n");
+
+ return paddr;
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-set-style: "BSD"
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
projects / xen.git / commitdiff