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