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