Merge branch 'x86/core' into core/ipi
[linux-2.6] / arch / x86 / mm / memtest.c
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
10 #include <asm/e820.h>
11
12 static u64 patterns[] __initdata = {
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, u64 start_bad, u64 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         reserve_early(start_bad, end_bad, "BAD RAM");
39 }
40
41 static void __init memtest(u64 pattern, u64 start_phys, u64 size)
42 {
43         u64 i, count;
44         u64 *start;
45         u64 start_bad, last_bad;
46         u64 start_phys_aligned;
47         size_t incr;
48
49         incr = sizeof(pattern);
50         start_phys_aligned = ALIGN(start_phys, incr);
51         count = (size - (start_phys_aligned - start_phys))/incr;
52         start = __va(start_phys_aligned);
53         start_bad = 0;
54         last_bad = 0;
55
56         for (i = 0; i < count; i++)
57                 start[i] = pattern;
58         for (i = 0; i < count; i++, start++, start_phys_aligned += incr) {
59                 if (*start == pattern)
60                         continue;
61                 if (start_phys_aligned == last_bad + incr) {
62                         last_bad += incr;
63                         continue;
64                 }
65                 if (start_bad)
66                         reserve_bad_mem(pattern, start_bad, last_bad + incr);
67                 start_bad = last_bad = start_phys_aligned;
68         }
69         if (start_bad)
70                 reserve_bad_mem(pattern, start_bad, last_bad + incr);
71 }
72
73 static void __init do_one_pass(u64 pattern, u64 start, u64 end)
74 {
75         u64 size = 0;
76
77         while (start < end) {
78                 start = find_e820_area_size(start, &size, 1);
79
80                 /* done ? */
81                 if (start >= end)
82                         break;
83                 if (start + size > end)
84                         size = end - start;
85
86                 printk(KERN_INFO "  %010llx - %010llx pattern %016llx\n",
87                        (unsigned long long) start,
88                        (unsigned long long) start + size,
89                        (unsigned long long) cpu_to_be64(pattern));
90                 memtest(pattern, start, size);
91
92                 start += size;
93         }
94 }
95
96 /* default is disabled */
97 static int memtest_pattern __initdata;
98
99 static int __init parse_memtest(char *arg)
100 {
101         if (arg)
102                 memtest_pattern = simple_strtoul(arg, NULL, 0);
103         else
104                 memtest_pattern = ARRAY_SIZE(patterns);
105
106         return 0;
107 }
108
109 early_param("memtest", parse_memtest);
110
111 void __init early_memtest(unsigned long start, unsigned long end)
112 {
113         unsigned int i;
114         unsigned int idx = 0;
115
116         if (!memtest_pattern)
117                 return;
118
119         printk(KERN_INFO "early_memtest: # of tests: %d\n", memtest_pattern);
120         for (i = 0; i < memtest_pattern; i++) {
121                 idx = i % ARRAY_SIZE(patterns);
122                 do_one_pass(patterns[idx], start, end);
123         }
124
125         if (idx > 0) {
126                 printk(KERN_INFO "early_memtest: wipe out "
127                        "test pattern from memory\n");
128                 /* additional test with pattern 0 will do this */
129                 do_one_pass(0, start, end);
130         }
131 }