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 (PHYSICAL_END - PHYSICAL_START), 6 * may 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) 2016, 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/setup.h> 18 #include <asm/page.h> 19 #include <asm/hcall.h> 20 21 extern unsigned long stacktop; 22 extern void io_init(void); 23 extern void setup_args_progname(const char *args); 24 25 u32 cpus[NR_CPUS] = { [0 ... NR_CPUS-1] = (~0U) }; 26 int nr_cpus; 27 uint64_t tb_hz; 28 29 struct mem_region mem_regions[NR_MEM_REGIONS]; 30 phys_addr_t __physical_start, __physical_end; 31 unsigned __icache_bytes, __dcache_bytes; 32 33 struct cpu_set_params { 34 unsigned icache_bytes; 35 unsigned dcache_bytes; 36 uint64_t tb_hz; 37 }; 38 39 #define EXCEPTION_STACK_SIZE (32*1024) /* 32kB */ 40 41 static char exception_stack[NR_CPUS][EXCEPTION_STACK_SIZE]; 42 43 static void cpu_set(int fdtnode, u64 regval, void *info) 44 { 45 static bool read_common_info = false; 46 struct cpu_set_params *params = info; 47 int cpu = nr_cpus++; 48 49 if (cpu >= NR_CPUS) { 50 printf("Number cpus exceeds maximum supported (%d).\n", 51 NR_CPUS); 52 assert(0); 53 } 54 cpus[cpu] = regval; 55 56 /* set exception stack address for this CPU (in SPGR0) */ 57 58 asm volatile ("mtsprg0 %[addr]" :: 59 [addr] "r" (exception_stack[cpu + 1])); 60 61 if (!read_common_info) { 62 const struct fdt_property *prop; 63 u32 *data; 64 65 prop = fdt_get_property(dt_fdt(), fdtnode, 66 "i-cache-line-size", NULL); 67 assert(prop != NULL); 68 data = (u32 *)prop->data; 69 params->icache_bytes = fdt32_to_cpu(*data); 70 71 prop = fdt_get_property(dt_fdt(), fdtnode, 72 "d-cache-line-size", NULL); 73 assert(prop != NULL); 74 data = (u32 *)prop->data; 75 params->dcache_bytes = fdt32_to_cpu(*data); 76 77 prop = fdt_get_property(dt_fdt(), fdtnode, 78 "timebase-frequency", NULL); 79 assert(prop != NULL); 80 data = (u32 *)prop->data; 81 params->tb_hz = fdt32_to_cpu(*data); 82 83 read_common_info = true; 84 } 85 } 86 87 static void cpu_init(void) 88 { 89 struct cpu_set_params params; 90 int ret; 91 92 nr_cpus = 0; 93 ret = dt_for_each_cpu_node(cpu_set, ¶ms); 94 assert(ret == 0); 95 __icache_bytes = params.icache_bytes; 96 __dcache_bytes = params.dcache_bytes; 97 tb_hz = params.tb_hz; 98 99 /* Interrupt Endianness */ 100 101 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ 102 hcall(H_SET_MODE, 1, 4, 0, 0); 103 #else 104 hcall(H_SET_MODE, 0, 4, 0, 0); 105 #endif 106 } 107 108 static void mem_init(phys_addr_t freemem_start) 109 { 110 struct dt_pbus_reg regs[NR_MEM_REGIONS]; 111 struct mem_region primary, mem = { 112 .start = (phys_addr_t)-1, 113 }; 114 int nr_regs, i; 115 116 nr_regs = dt_get_memory_params(regs, NR_MEM_REGIONS); 117 assert(nr_regs > 0); 118 119 primary.end = 0; 120 121 for (i = 0; i < nr_regs; ++i) { 122 mem_regions[i].start = regs[i].addr; 123 mem_regions[i].end = regs[i].addr + regs[i].size; 124 125 /* 126 * pick the region we're in for our primary region 127 */ 128 if (freemem_start >= mem_regions[i].start 129 && freemem_start < mem_regions[i].end) { 130 mem_regions[i].flags |= MR_F_PRIMARY; 131 primary = mem_regions[i]; 132 } 133 134 /* 135 * set the lowest and highest addresses found, 136 * ignoring potential gaps 137 */ 138 if (mem_regions[i].start < mem.start) 139 mem.start = mem_regions[i].start; 140 if (mem_regions[i].end > mem.end) 141 mem.end = mem_regions[i].end; 142 } 143 assert(primary.end != 0); 144 // assert(!(mem.start & ~PHYS_MASK) && !((mem.end - 1) & ~PHYS_MASK)); 145 146 __physical_start = mem.start; /* PHYSICAL_START */ 147 __physical_end = mem.end; /* PHYSICAL_END */ 148 149 phys_alloc_init(freemem_start, primary.end - freemem_start); 150 phys_alloc_set_minimum_alignment(__icache_bytes > __dcache_bytes 151 ? __icache_bytes : __dcache_bytes); 152 } 153 154 void setup(const void *fdt) 155 { 156 void *freemem = &stacktop; 157 const char *bootargs; 158 u32 fdt_size; 159 int ret; 160 161 /* 162 * Before calling mem_init we need to move the fdt to a safe 163 * location. We move it above the stack to construct the memory 164 * map illustrated below: 165 * 166 * +----------------------+ <-- top of physical memory 167 * | | 168 * ~ ~ 169 * | | 170 * +----------------------+ <-- top of FDT 171 * | | 172 * +----------------------+ <-- top of cpu0's stack 173 * | | 174 * +----------------------+ <-- top of text/data/bss sections, 175 * | | see arm/flat.lds 176 * | | 177 * +----------------------+ <-- load address 178 * | | 179 * +----------------------+ 180 */ 181 fdt_size = fdt_totalsize(fdt); 182 ret = fdt_move(fdt, freemem, fdt_size); 183 assert(ret == 0); 184 ret = dt_init(freemem); 185 assert(ret == 0); 186 freemem += fdt_size; 187 188 /* call init functions */ 189 cpu_init(); 190 191 /* cpu_init must be called before mem_init */ 192 mem_init(PAGE_ALIGN((unsigned long)freemem)); 193 194 /* mem_init must be called before io_init */ 195 io_init(); 196 197 /* finish setup */ 198 ret = dt_get_bootargs(&bootargs); 199 assert(ret == 0 || ret == -FDT_ERR_NOTFOUND); 200 setup_args_progname(bootargs); 201 } 202