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 u32 cpus[NR_CPUS] = { [0 ... NR_CPUS-1] = (~0U) }; 28 int nr_cpus; 29 30 struct mem_region mem_regions[NR_MEM_REGIONS]; 31 phys_addr_t __phys_offset, __phys_end; 32 33 static void cpu_set(int fdtnode __unused, u32 regval, void *info __unused) 34 { 35 int cpu = nr_cpus++; 36 37 if (cpu >= NR_CPUS) { 38 printf("Number cpus exceeds maximum supported (%d).\n", 39 NR_CPUS); 40 assert(0); 41 } 42 cpus[cpu] = regval; 43 set_cpu_present(cpu, true); 44 } 45 46 static void cpu_init(void) 47 { 48 int ret; 49 50 nr_cpus = 0; 51 ret = dt_for_each_cpu_node(cpu_set, NULL); 52 assert(ret == 0); 53 set_cpu_online(0, true); 54 } 55 56 static void mem_init(phys_addr_t freemem_start) 57 { 58 struct dt_pbus_reg regs[NR_MEM_REGIONS]; 59 struct mem_region primary, mem = { 60 .start = (phys_addr_t)-1, 61 }; 62 int nr_regs, i; 63 64 nr_regs = dt_get_memory_params(regs, NR_MEM_REGIONS); 65 assert(nr_regs > 0); 66 67 primary.end = 0; 68 69 for (i = 0; i < nr_regs; ++i) { 70 mem_regions[i].start = regs[i].addr; 71 mem_regions[i].end = regs[i].addr + regs[i].size; 72 73 /* 74 * pick the region we're in for our primary region 75 */ 76 if (freemem_start >= mem_regions[i].start 77 && freemem_start < mem_regions[i].end) { 78 mem_regions[i].flags |= MR_F_PRIMARY; 79 primary = mem_regions[i]; 80 } 81 82 /* 83 * set the lowest and highest addresses found, 84 * ignoring potential gaps 85 */ 86 if (mem_regions[i].start < mem.start) 87 mem.start = mem_regions[i].start; 88 if (mem_regions[i].end > mem.end) 89 mem.end = mem_regions[i].end; 90 } 91 assert(primary.end != 0); 92 assert(!(mem.start & ~PHYS_MASK) && !((mem.end - 1) & ~PHYS_MASK)); 93 94 __phys_offset = mem.start; /* PHYS_OFFSET */ 95 __phys_end = mem.end; /* PHYS_END */ 96 97 phys_alloc_init(freemem_start, primary.end - freemem_start); 98 phys_alloc_set_minimum_alignment(SMP_CACHE_BYTES); 99 100 mmu_enable_idmap(); 101 } 102 103 void setup(const void *fdt) 104 { 105 const char *bootargs; 106 u32 fdt_size; 107 int ret; 108 109 /* 110 * Move the fdt to just above the stack. The free memory 111 * then starts just after the fdt. 112 */ 113 fdt_size = fdt_totalsize(fdt); 114 ret = fdt_move(fdt, &stacktop, fdt_size); 115 assert(ret == 0); 116 ret = dt_init(&stacktop); 117 assert(ret == 0); 118 119 mem_init(PAGE_ALIGN((unsigned long)&stacktop + fdt_size)); 120 io_init(); 121 cpu_init(); 122 123 thread_info_init(current_thread_info(), 0); 124 125 ret = dt_get_bootargs(&bootargs); 126 assert(ret == 0); 127 setup_args_progname(bootargs); 128 } 129