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(const char *args); 26 27 u32 cpus[NR_CPUS] = { [0 ... NR_CPUS-1] = (~0U) }; 28 int nr_cpus; 29 30 phys_addr_t __phys_offset, __phys_end; 31 32 static void cpu_set(int fdtnode __unused, u32 regval, void *info __unused) 33 { 34 int cpu = nr_cpus++; 35 assert(cpu < NR_CPUS); 36 cpus[cpu] = regval; 37 set_cpu_present(cpu, true); 38 } 39 40 static void cpu_init(void) 41 { 42 nr_cpus = 0; 43 assert(dt_for_each_cpu_node(cpu_set, NULL) == 0); 44 set_cpu_online(0, true); 45 } 46 47 static void mem_init(phys_addr_t freemem_start) 48 { 49 /* we only expect one membank to be defined in the DT */ 50 struct dt_pbus_reg regs[1]; 51 phys_addr_t mem_start, mem_end; 52 53 assert(dt_get_memory_params(regs, 1)); 54 55 mem_start = regs[0].addr; 56 mem_end = mem_start + regs[0].size; 57 58 assert(!(mem_start & ~PHYS_MASK) && !((mem_end-1) & ~PHYS_MASK)); 59 assert(freemem_start >= mem_start && freemem_start < mem_end); 60 61 __phys_offset = mem_start; /* PHYS_OFFSET */ 62 __phys_end = mem_end; /* PHYS_END */ 63 64 phys_alloc_init(freemem_start, mem_end - freemem_start); 65 phys_alloc_set_minimum_alignment(SMP_CACHE_BYTES); 66 67 mmu_enable_idmap(); 68 } 69 70 void setup(const void *fdt) 71 { 72 const char *bootargs; 73 u32 fdt_size; 74 75 /* 76 * Move the fdt to just above the stack. The free memory 77 * then starts just after the fdt. 78 */ 79 fdt_size = fdt_totalsize(fdt); 80 assert(fdt_move(fdt, &stacktop, fdt_size) == 0); 81 assert(dt_init(&stacktop) == 0); 82 83 mem_init(PAGE_ALIGN((unsigned long)&stacktop + fdt_size)); 84 io_init(); 85 cpu_init(); 86 87 thread_info_init(current_thread_info(), 0); 88 89 assert(dt_get_bootargs(&bootargs) == 0); 90 setup_args(bootargs); 91 } 92