| // SPDX-License-Identifier: GPL-2.0 |
| #include <linux/kernel.h> |
| #include <linux/types.h> |
| #include <linux/init.h> |
| #include <linux/memblock.h> |
| |
| static u64 patterns[] __initdata = { |
| /* The first entry has to be 0 to leave memtest with zeroed memory */ |
| 0, |
| 0xffffffffffffffffULL, |
| 0x5555555555555555ULL, |
| 0xaaaaaaaaaaaaaaaaULL, |
| 0x1111111111111111ULL, |
| 0x2222222222222222ULL, |
| 0x4444444444444444ULL, |
| 0x8888888888888888ULL, |
| 0x3333333333333333ULL, |
| 0x6666666666666666ULL, |
| 0x9999999999999999ULL, |
| 0xccccccccccccccccULL, |
| 0x7777777777777777ULL, |
| 0xbbbbbbbbbbbbbbbbULL, |
| 0xddddddddddddddddULL, |
| 0xeeeeeeeeeeeeeeeeULL, |
| 0x7a6c7258554e494cULL, /* yeah ;-) */ |
| }; |
| |
| static void __init reserve_bad_mem(u64 pattern, phys_addr_t start_bad, phys_addr_t end_bad) |
| { |
| pr_info(" %016llx bad mem addr %pa - %pa reserved\n", |
| cpu_to_be64(pattern), &start_bad, &end_bad); |
| memblock_reserve(start_bad, end_bad - start_bad); |
| } |
| |
| static void __init memtest(u64 pattern, phys_addr_t start_phys, phys_addr_t size) |
| { |
| u64 *p, *start, *end; |
| phys_addr_t start_bad, last_bad; |
| phys_addr_t start_phys_aligned; |
| const size_t incr = sizeof(pattern); |
| |
| start_phys_aligned = ALIGN(start_phys, incr); |
| start = __va(start_phys_aligned); |
| end = start + (size - (start_phys_aligned - start_phys)) / incr; |
| start_bad = 0; |
| last_bad = 0; |
| |
| for (p = start; p < end; p++) |
| *p = pattern; |
| |
| for (p = start; p < end; p++, start_phys_aligned += incr) { |
| if (*p == pattern) |
| continue; |
| if (start_phys_aligned == last_bad + incr) { |
| last_bad += incr; |
| continue; |
| } |
| if (start_bad) |
| reserve_bad_mem(pattern, start_bad, last_bad + incr); |
| start_bad = last_bad = start_phys_aligned; |
| } |
| if (start_bad) |
| reserve_bad_mem(pattern, start_bad, last_bad + incr); |
| } |
| |
| static void __init do_one_pass(u64 pattern, phys_addr_t start, phys_addr_t end) |
| { |
| u64 i; |
| phys_addr_t this_start, this_end; |
| |
| for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE, &this_start, |
| &this_end, NULL) { |
| this_start = clamp(this_start, start, end); |
| this_end = clamp(this_end, start, end); |
| if (this_start < this_end) { |
| pr_info(" %pa - %pa pattern %016llx\n", |
| &this_start, &this_end, cpu_to_be64(pattern)); |
| memtest(pattern, this_start, this_end - this_start); |
| } |
| } |
| } |
| |
| /* default is disabled */ |
| static unsigned int memtest_pattern __initdata; |
| |
| static int __init parse_memtest(char *arg) |
| { |
| int ret = 0; |
| |
| if (arg) |
| ret = kstrtouint(arg, 0, &memtest_pattern); |
| else |
| memtest_pattern = ARRAY_SIZE(patterns); |
| |
| return ret; |
| } |
| |
| early_param("memtest", parse_memtest); |
| |
| void __init early_memtest(phys_addr_t start, phys_addr_t end) |
| { |
| unsigned int i; |
| unsigned int idx = 0; |
| |
| if (!memtest_pattern) |
| return; |
| |
| pr_info("early_memtest: # of tests: %u\n", memtest_pattern); |
| for (i = memtest_pattern-1; i < UINT_MAX; --i) { |
| idx = i % ARRAY_SIZE(patterns); |
| do_one_pass(patterns[idx], start, end); |
| } |
| } |