1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * The simple platform -- for booting when firmware doesn't supply a device 4 * tree or any platform configuration information. 5 * All data is extracted from an embedded device tree 6 * blob. 7 * 8 * Authors: Scott Wood <scottwood@freescale.com> 9 * Grant Likely <grant.likely@secretlab.ca> 10 * 11 * Copyright (c) 2007 Freescale Semiconductor, Inc. 12 * Copyright (c) 2008 Secret Lab Technologies Ltd. 13 */ 14 15 #include "ops.h" 16 #include "types.h" 17 #include "io.h" 18 #include "stdio.h" 19 #include <libfdt.h> 20 21 BSS_STACK(4*1024); 22 23 extern int platform_specific_init(void) __attribute__((weak)); 24 25 void platform_init(unsigned long r3, unsigned long r4, unsigned long r5, 26 unsigned long r6, unsigned long r7) 27 { 28 const u32 *na, *ns, *reg, *timebase; 29 u64 memsize64; 30 int node, size, i; 31 32 /* Make sure FDT blob is sane */ 33 if (fdt_check_header(_dtb_start) != 0) 34 fatal("Invalid device tree blob\n"); 35 36 /* Find the #address-cells and #size-cells properties */ 37 node = fdt_path_offset(_dtb_start, "/"); 38 if (node < 0) 39 fatal("Cannot find root node\n"); 40 na = fdt_getprop(_dtb_start, node, "#address-cells", &size); 41 if (!na || (size != 4)) 42 fatal("Cannot find #address-cells property"); 43 ns = fdt_getprop(_dtb_start, node, "#size-cells", &size); 44 if (!ns || (size != 4)) 45 fatal("Cannot find #size-cells property"); 46 47 /* Find the memory range */ 48 node = fdt_node_offset_by_prop_value(_dtb_start, -1, "device_type", 49 "memory", sizeof("memory")); 50 if (node < 0) 51 fatal("Cannot find memory node\n"); 52 reg = fdt_getprop(_dtb_start, node, "reg", &size); 53 if (size < (*na+*ns) * sizeof(u32)) 54 fatal("cannot get memory range\n"); 55 56 /* Only interested in memory based at 0 */ 57 for (i = 0; i < *na; i++) 58 if (*reg++ != 0) 59 fatal("Memory range is not based at address 0\n"); 60 61 /* get the memsize and truncate it to under 4G on 32 bit machines */ 62 memsize64 = 0; 63 for (i = 0; i < *ns; i++) 64 memsize64 = (memsize64 << 32) | *reg++; 65 if (sizeof(void *) == 4 && memsize64 >= 0x100000000ULL) 66 memsize64 = 0xffffffff; 67 68 /* finally, setup the timebase */ 69 node = fdt_node_offset_by_prop_value(_dtb_start, -1, "device_type", 70 "cpu", sizeof("cpu")); 71 if (!node) 72 fatal("Cannot find cpu node\n"); 73 timebase = fdt_getprop(_dtb_start, node, "timebase-frequency", &size); 74 if (timebase && (size == 4)) 75 timebase_period_ns = 1000000000 / *timebase; 76 77 /* Now we have the memory size; initialize the heap */ 78 simple_alloc_init(_end, memsize64 - (unsigned long)_end, 32, 64); 79 80 /* prepare the device tree and find the console */ 81 fdt_init(_dtb_start); 82 83 if (platform_specific_init) 84 platform_specific_init(); 85 86 serial_console_init(); 87 } 88