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 0,
13 0xffffffffffffffffULL,
14 0x5555555555555555ULL,
15 0xaaaaaaaaaaaaaaaaULL,
16 0x1111111111111111ULL,
17 0x2222222222222222ULL,
18 0x4444444444444444ULL,
19 0x8888888888888888ULL,
20 0x3333333333333333ULL,
21 0x6666666666666666ULL,
22 0x9999999999999999ULL,
23 0xccccccccccccccccULL,
24 0x7777777777777777ULL,
25 0xbbbbbbbbbbbbbbbbULL,
26 0xddddddddddddddddULL,
27 0xeeeeeeeeeeeeeeeeULL,
28 0x7a6c7258554e494cULL, /* yeah ;-) */
29 };
30
reserve_bad_mem(u64 pattern,u64 start_bad,u64 end_bad)31 static void __init reserve_bad_mem(u64 pattern, u64 start_bad, u64 end_bad)
32 {
33 printk(KERN_INFO " %016llx bad mem addr %010llx - %010llx reserved\n",
34 (unsigned long long) pattern,
35 (unsigned long long) start_bad,
36 (unsigned long long) end_bad);
37 memblock_reserve(start_bad, end_bad - start_bad);
38 }
39
memtest(u64 pattern,u64 start_phys,u64 size)40 static void __init memtest(u64 pattern, u64 start_phys, u64 size)
41 {
42 u64 *p, *start, *end;
43 u64 start_bad, last_bad;
44 u64 start_phys_aligned;
45 const size_t incr = sizeof(pattern);
46
47 start_phys_aligned = ALIGN(start_phys, incr);
48 start = __va(start_phys_aligned);
49 end = start + (size - (start_phys_aligned - start_phys)) / incr;
50 start_bad = 0;
51 last_bad = 0;
52
53 for (p = start; p < end; p++)
54 *p = pattern;
55
56 for (p = start; p < end; p++, start_phys_aligned += incr) {
57 if (*p == pattern)
58 continue;
59 if (start_phys_aligned == last_bad + incr) {
60 last_bad += incr;
61 continue;
62 }
63 if (start_bad)
64 reserve_bad_mem(pattern, start_bad, last_bad + incr);
65 start_bad = last_bad = start_phys_aligned;
66 }
67 if (start_bad)
68 reserve_bad_mem(pattern, start_bad, last_bad + incr);
69 }
70
do_one_pass(u64 pattern,u64 start,u64 end)71 static void __init do_one_pass(u64 pattern, u64 start, u64 end)
72 {
73 u64 i;
74 phys_addr_t this_start, this_end;
75
76 for_each_free_mem_range(i, MAX_NUMNODES, &this_start, &this_end, NULL) {
77 this_start = clamp_t(phys_addr_t, this_start, start, end);
78 this_end = clamp_t(phys_addr_t, this_end, start, end);
79 if (this_start < this_end) {
80 printk(KERN_INFO " %010llx - %010llx pattern %016llx\n",
81 (unsigned long long)this_start,
82 (unsigned long long)this_end,
83 (unsigned long long)cpu_to_be64(pattern));
84 memtest(pattern, this_start, this_end - this_start);
85 }
86 }
87 }
88
89 /* default is disabled */
90 static int memtest_pattern __initdata;
91
parse_memtest(char * arg)92 static int __init parse_memtest(char *arg)
93 {
94 if (arg)
95 memtest_pattern = simple_strtoul(arg, NULL, 0);
96 else
97 memtest_pattern = ARRAY_SIZE(patterns);
98
99 return 0;
100 }
101
102 early_param("memtest", parse_memtest);
103
early_memtest(unsigned long start,unsigned long end)104 void __init early_memtest(unsigned long start, unsigned long end)
105 {
106 unsigned int i;
107 unsigned int idx = 0;
108
109 if (!memtest_pattern)
110 return;
111
112 printk(KERN_INFO "early_memtest: # of tests: %d\n", memtest_pattern);
113 for (i = 0; i < memtest_pattern; i++) {
114 idx = i % ARRAY_SIZE(patterns);
115 do_one_pass(patterns[idx], start, end);
116 }
117
118 if (idx > 0) {
119 printk(KERN_INFO "early_memtest: wipe out "
120 "test pattern from memory\n");
121 /* additional test with pattern 0 will do this */
122 do_one_pass(0, start, end);
123 }
124 }
125