/* * The simple platform -- for booting when firmware doesn't supply a device * tree or any platform configuration information. * All data is extracted from an embedded device tree * blob. * * Authors: Scott Wood <scottwood@freescale.com> * Grant Likely <grant.likely@secretlab.ca> * * Copyright (c) 2007 Freescale Semiconductor, Inc. * Copyright (c) 2008 Secret Lab Technologies Ltd. * * 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 "ops.h" #include "types.h" #include "io.h" #include "stdio.h" #include <libfdt.h> BSS_STACK(4*1024); extern int platform_specific_init(void) __attribute__((weak)); void platform_init(unsigned long r3, unsigned long r4, unsigned long r5, unsigned long r6, unsigned long r7) { const u32 *na, *ns, *reg, *timebase; u64 memsize64; int node, size, i; /* Make sure FDT blob is sane */ if (fdt_check_header(_dtb_start) != 0) fatal("Invalid device tree blob\n"); /* Find the #address-cells and #size-cells properties */ node = fdt_path_offset(_dtb_start, "/"); if (node < 0) fatal("Cannot find root node\n"); na = fdt_getprop(_dtb_start, node, "#address-cells", &size); if (!na || (size != 4)) fatal("Cannot find #address-cells property"); ns = fdt_getprop(_dtb_start, node, "#size-cells", &size); if (!ns || (size != 4)) fatal("Cannot find #size-cells property"); /* Find the memory range */ node = fdt_node_offset_by_prop_value(_dtb_start, -1, "device_type", "memory", sizeof("memory")); if (node < 0) fatal("Cannot find memory node\n"); reg = fdt_getprop(_dtb_start, node, "reg", &size); if (size < (*na+*ns) * sizeof(u32)) fatal("cannot get memory range\n"); /* Only interested in memory based at 0 */ for (i = 0; i < *na; i++) if (*reg++ != 0) fatal("Memory range is not based at address 0\n"); /* get the memsize and truncate it to under 4G on 32 bit machines */ memsize64 = 0; for (i = 0; i < *ns; i++) memsize64 = (memsize64 << 32) | *reg++; if (sizeof(void *) == 4 && memsize64 >= 0x100000000ULL) memsize64 = 0xffffffff; /* finally, setup the timebase */ node = fdt_node_offset_by_prop_value(_dtb_start, -1, "device_type", "cpu", sizeof("cpu")); if (!node) fatal("Cannot find cpu node\n"); timebase = fdt_getprop(_dtb_start, node, "timebase-frequency", &size); if (timebase && (size == 4)) timebase_period_ns = 1000000000 / *timebase; /* Now we have the memory size; initialize the heap */ simple_alloc_init(_end, memsize64 - (unsigned long)_end, 32, 64); /* prepare the device tree and find the console */ fdt_init(_dtb_start); if (platform_specific_init) platform_specific_init(); serial_console_init(); } |