1 /* 2 * Initialize machine setup information and I/O. 3 * 4 * After running setup() unit tests may query how many cpus they have 5 * (nr_cpus), how much memory they have (PHYS_END - PHYS_OFFSET), may 6 * use dynamic memory allocation (malloc, etc.), printf, and exit. 7 * Finally, argc and argv are also ready to be passed to main(). 8 * 9 * Copyright (C) 2014, Red Hat Inc, Andrew Jones <drjones@redhat.com> 10 * 11 * This work is licensed under the terms of the GNU LGPL, version 2. 12 */ 13 #include <libcflat.h> 14 #include <libfdt/libfdt.h> 15 #include <devicetree.h> 16 #include <alloc.h> 17 #include <alloc_phys.h> 18 #include <alloc_page.h> 19 #include <argv.h> 20 #include <asm/thread_info.h> 21 #include <asm/setup.h> 22 #include <asm/page.h> 23 #include <asm/smp.h> 24 25 #include "io.h" 26 27 extern unsigned long stacktop; 28 29 char *initrd; 30 u32 initrd_size; 31 32 u64 cpus[NR_CPUS] = { [0 ... NR_CPUS-1] = (u64)~0 }; 33 int nr_cpus; 34 35 struct mem_region mem_regions[NR_MEM_REGIONS]; 36 phys_addr_t __phys_offset, __phys_end; 37 38 int mpidr_to_cpu(uint64_t mpidr) 39 { 40 int i; 41 42 for (i = 0; i < nr_cpus; ++i) 43 if (cpus[i] == (mpidr & MPIDR_HWID_BITMASK)) 44 return i; 45 return -1; 46 } 47 48 static void cpu_set(int fdtnode __unused, u64 regval, void *info __unused) 49 { 50 int cpu = nr_cpus++; 51 52 assert_msg(cpu < NR_CPUS, "Number cpus exceeds maximum supported (%d).", NR_CPUS); 53 54 cpus[cpu] = regval; 55 set_cpu_present(cpu, true); 56 } 57 58 static void cpu_init(void) 59 { 60 int ret; 61 62 nr_cpus = 0; 63 ret = dt_for_each_cpu_node(cpu_set, NULL); 64 assert(ret == 0); 65 set_cpu_online(0, true); 66 } 67 68 static void mem_init(phys_addr_t freemem_start) 69 { 70 struct dt_pbus_reg regs[NR_MEM_REGIONS]; 71 struct mem_region primary, mem = { 72 .start = (phys_addr_t)-1, 73 }; 74 phys_addr_t base, top; 75 int nr_regs, i; 76 77 nr_regs = dt_get_memory_params(regs, NR_MEM_REGIONS); 78 assert(nr_regs > 0); 79 80 primary = (struct mem_region){ 0 }; 81 82 for (i = 0; i < nr_regs; ++i) { 83 mem_regions[i].start = regs[i].addr; 84 mem_regions[i].end = regs[i].addr + regs[i].size; 85 86 /* 87 * pick the region we're in for our primary region 88 */ 89 if (freemem_start >= mem_regions[i].start 90 && freemem_start < mem_regions[i].end) { 91 mem_regions[i].flags |= MR_F_PRIMARY; 92 primary = mem_regions[i]; 93 } 94 95 /* 96 * set the lowest and highest addresses found, 97 * ignoring potential gaps 98 */ 99 if (mem_regions[i].start < mem.start) 100 mem.start = mem_regions[i].start; 101 if (mem_regions[i].end > mem.end) 102 mem.end = mem_regions[i].end; 103 } 104 assert(primary.end != 0); 105 assert(!(mem.start & ~PHYS_MASK) && !((mem.end - 1) & ~PHYS_MASK)); 106 107 __phys_offset = primary.start; /* PHYS_OFFSET */ 108 __phys_end = primary.end; /* PHYS_END */ 109 110 phys_alloc_init(freemem_start, primary.end - freemem_start); 111 phys_alloc_set_minimum_alignment(SMP_CACHE_BYTES); 112 113 phys_alloc_get_unused(&base, &top); 114 base = PAGE_ALIGN(base); 115 top = top & PAGE_MASK; 116 assert(sizeof(long) == 8 || !(base >> 32)); 117 if (sizeof(long) != 8 && (top >> 32) != 0) 118 top = ((uint64_t)1 << 32); 119 free_pages((void *)(unsigned long)base, top - base); 120 page_alloc_ops_enable(); 121 } 122 123 void setup(const void *fdt) 124 { 125 void *freemem = &stacktop; 126 const char *bootargs, *tmp; 127 u32 fdt_size; 128 int ret; 129 130 /* 131 * Before calling mem_init we need to move the fdt and initrd 132 * to safe locations. We move them to construct the memory 133 * map illustrated below: 134 * 135 * +----------------------+ <-- top of physical memory 136 * | | 137 * ~ ~ 138 * | | 139 * +----------------------+ <-- top of initrd 140 * | | 141 * +----------------------+ <-- top of FDT 142 * | | 143 * +----------------------+ <-- top of cpu0's stack 144 * | | 145 * +----------------------+ <-- top of text/data/bss sections, 146 * | | see arm/flat.lds 147 * | | 148 * +----------------------+ <-- load address 149 * | | 150 * +----------------------+ 151 */ 152 fdt_size = fdt_totalsize(fdt); 153 ret = fdt_move(fdt, freemem, fdt_size); 154 assert(ret == 0); 155 ret = dt_init(freemem); 156 assert(ret == 0); 157 freemem += fdt_size; 158 159 ret = dt_get_initrd(&tmp, &initrd_size); 160 assert(ret == 0 || ret == -FDT_ERR_NOTFOUND); 161 if (ret == 0) { 162 initrd = freemem; 163 memmove(initrd, tmp, initrd_size); 164 freemem += initrd_size; 165 } 166 167 /* call init functions */ 168 mem_init(PAGE_ALIGN((unsigned long)freemem)); 169 cpu_init(); 170 171 /* cpu_init must be called before thread_info_init */ 172 thread_info_init(current_thread_info(), 0); 173 174 /* mem_init must be called before io_init */ 175 io_init(); 176 177 /* finish setup */ 178 ret = dt_get_bootargs(&bootargs); 179 assert(ret == 0 || ret == -FDT_ERR_NOTFOUND); 180 setup_args_progname(bootargs); 181 182 if (initrd) { 183 /* environ is currently the only file in the initrd */ 184 char *env = malloc(initrd_size); 185 memcpy(env, initrd, initrd_size); 186 setup_env(env, initrd_size); 187 } 188 } 189