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 27 u64 cpus[NR_CPUS] = { [0 ... NR_CPUS-1] = (u64)~0 }; 28 int nr_cpus; 29 30 struct mem_region mem_regions[NR_MEM_REGIONS]; 31 phys_addr_t __phys_offset, __phys_end; 32 33 int mpidr_to_cpu(uint64_t mpidr) 34 { 35 int i; 36 37 for (i = 0; i < nr_cpus; ++i) 38 if (cpus[i] == (mpidr & MPIDR_HWID_BITMASK)) 39 return i; 40 return -1; 41 } 42 43 static void cpu_set(int fdtnode __unused, u64 regval, void *info __unused) 44 { 45 int cpu = nr_cpus++; 46 47 if (cpu >= NR_CPUS) { 48 printf("Number cpus exceeds maximum supported (%d).\n", 49 NR_CPUS); 50 assert(0); 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 const char *bootargs; 116 u32 fdt_size; 117 int ret; 118 119 /* 120 * Move the fdt to just above the stack. The free memory 121 * then starts just after the fdt. 122 */ 123 fdt_size = fdt_totalsize(fdt); 124 ret = fdt_move(fdt, &stacktop, fdt_size); 125 assert(ret == 0); 126 ret = dt_init(&stacktop); 127 assert(ret == 0); 128 129 cpu_init(); 130 131 /* cpu_init must be called before thread_info_init */ 132 thread_info_init(current_thread_info(), 0); 133 134 /* thread_info_init must be called before mem_init */ 135 mem_init(PAGE_ALIGN((unsigned long)&stacktop + fdt_size)); 136 137 /* mem_init must be called before io_init */ 138 io_init(); 139 140 ret = dt_get_bootargs(&bootargs); 141 assert(ret == 0); 142 setup_args_progname(bootargs); 143 } 144