Merge tag 'devicetree-fixes-for-6.4-1' of git://git.kernel.org/pub/scm/linux/kernel...
[platform/kernel/linux-starfive.git] / mm / memtest.c
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/kernel.h>
3 #include <linux/types.h>
4 #include <linux/init.h>
5 #include <linux/memblock.h>
6
7 bool early_memtest_done;
8 phys_addr_t early_memtest_bad_size;
9
10 static u64 patterns[] __initdata = {
11         /* The first entry has to be 0 to leave memtest with zeroed memory */
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
31 static void __init reserve_bad_mem(u64 pattern, phys_addr_t start_bad, phys_addr_t end_bad)
32 {
33         pr_info("  %016llx bad mem addr %pa - %pa reserved\n",
34                 cpu_to_be64(pattern), &start_bad, &end_bad);
35         memblock_reserve(start_bad, end_bad - start_bad);
36         early_memtest_bad_size += (end_bad - start_bad);
37 }
38
39 static void __init memtest(u64 pattern, phys_addr_t start_phys, phys_addr_t size)
40 {
41         u64 *p, *start, *end;
42         phys_addr_t start_bad, last_bad;
43         phys_addr_t start_phys_aligned;
44         const size_t incr = sizeof(pattern);
45
46         start_phys_aligned = ALIGN(start_phys, incr);
47         start = __va(start_phys_aligned);
48         end = start + (size - (start_phys_aligned - start_phys)) / incr;
49         start_bad = 0;
50         last_bad = 0;
51
52         for (p = start; p < end; p++)
53                 *p = pattern;
54
55         for (p = start; p < end; p++, start_phys_aligned += incr) {
56                 if (*p == pattern)
57                         continue;
58                 if (start_phys_aligned == last_bad + incr) {
59                         last_bad += incr;
60                         continue;
61                 }
62                 if (start_bad)
63                         reserve_bad_mem(pattern, start_bad, last_bad + incr);
64                 start_bad = last_bad = start_phys_aligned;
65         }
66         if (start_bad)
67                 reserve_bad_mem(pattern, start_bad, last_bad + incr);
68
69         early_memtest_done = true;
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                         pr_info("  %pa - %pa pattern %016llx\n",
83                                 &this_start, &this_end, cpu_to_be64(pattern));
84                         memtest(pattern, this_start, this_end - this_start);
85                 }
86         }
87 }
88
89 /* default is disabled */
90 static unsigned int memtest_pattern __initdata;
91
92 static int __init parse_memtest(char *arg)
93 {
94         int ret = 0;
95
96         if (arg)
97                 ret = kstrtouint(arg, 0, &memtest_pattern);
98         else
99                 memtest_pattern = ARRAY_SIZE(patterns);
100
101         return ret;
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         pr_info("early_memtest: # of tests: %u\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 }