1 #include <linux/kernel.h> 2 #include <linux/errno.h> 3 #include <linux/string.h> 4 #include <linux/types.h> 5 #include <linux/mm.h> 6 #include <linux/smp.h> 7 #include <linux/init.h> 8 #include <linux/pfn.h> 9 #include <linux/memblock.h> 10 11 static u64 patterns[] __initdata = { 12 /* The first entry has to be 0 to leave memtest with zeroed memory */ 13 0, 14 0xffffffffffffffffULL, 15 0x5555555555555555ULL, 16 0xaaaaaaaaaaaaaaaaULL, 17 0x1111111111111111ULL, 18 0x2222222222222222ULL, 19 0x4444444444444444ULL, 20 0x8888888888888888ULL, 21 0x3333333333333333ULL, 22 0x6666666666666666ULL, 23 0x9999999999999999ULL, 24 0xccccccccccccccccULL, 25 0x7777777777777777ULL, 26 0xbbbbbbbbbbbbbbbbULL, 27 0xddddddddddddddddULL, 28 0xeeeeeeeeeeeeeeeeULL, 29 0x7a6c7258554e494cULL, /* yeah ;-) */ 30 }; 31 32 static void __init reserve_bad_mem(u64 pattern, phys_addr_t start_bad, phys_addr_t end_bad) 33 { 34 printk(KERN_INFO " %016llx bad mem addr %010llx - %010llx reserved\n", 35 (unsigned long long) pattern, 36 (unsigned long long) start_bad, 37 (unsigned long long) end_bad); 38 memblock_reserve(start_bad, end_bad - start_bad); 39 } 40 41 static void __init memtest(u64 pattern, phys_addr_t start_phys, phys_addr_t size) 42 { 43 u64 *p, *start, *end; 44 phys_addr_t start_bad, last_bad; 45 phys_addr_t start_phys_aligned; 46 const size_t incr = sizeof(pattern); 47 48 start_phys_aligned = ALIGN(start_phys, incr); 49 start = __va(start_phys_aligned); 50 end = start + (size - (start_phys_aligned - start_phys)) / incr; 51 start_bad = 0; 52 last_bad = 0; 53 54 for (p = start; p < end; p++) 55 *p = pattern; 56 57 for (p = start; p < end; p++, start_phys_aligned += incr) { 58 if (*p == pattern) 59 continue; 60 if (start_phys_aligned == last_bad + incr) { 61 last_bad += incr; 62 continue; 63 } 64 if (start_bad) 65 reserve_bad_mem(pattern, start_bad, last_bad + incr); 66 start_bad = last_bad = start_phys_aligned; 67 } 68 if (start_bad) 69 reserve_bad_mem(pattern, start_bad, last_bad + incr); 70 } 71 72 static void __init do_one_pass(u64 pattern, phys_addr_t start, phys_addr_t end) 73 { 74 u64 i; 75 phys_addr_t this_start, this_end; 76 77 for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE, &this_start, 78 &this_end, NULL) { 79 this_start = clamp(this_start, start, end); 80 this_end = clamp(this_end, start, end); 81 if (this_start < this_end) { 82 printk(KERN_INFO " %010llx - %010llx pattern %016llx\n", 83 (unsigned long long)this_start, 84 (unsigned long long)this_end, 85 (unsigned long long)cpu_to_be64(pattern)); 86 memtest(pattern, this_start, this_end - this_start); 87 } 88 } 89 } 90 91 /* default is disabled */ 92 static int memtest_pattern __initdata; 93 94 static int __init parse_memtest(char *arg) 95 { 96 if (arg) 97 memtest_pattern = simple_strtoul(arg, NULL, 0); 98 else 99 memtest_pattern = ARRAY_SIZE(patterns); 100 101 return 0; 102 } 103 104 early_param("memtest", parse_memtest); 105 106 void __init early_memtest(phys_addr_t start, phys_addr_t end) 107 { 108 unsigned int i; 109 unsigned int idx = 0; 110 111 if (!memtest_pattern) 112 return; 113 114 printk(KERN_INFO "early_memtest: # of tests: %d\n", memtest_pattern); 115 for (i = memtest_pattern-1; i < UINT_MAX; --i) { 116 idx = i % ARRAY_SIZE(patterns); 117 do_one_pass(patterns[idx], start, end); 118 } 119 } 120