1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2010
4  * Heiko Schocher, DENX Software Engineering, hs@denx.de.
5  */
6 
7 #include <common.h>
8 #include <cpu_func.h>
9 #include <asm/cache.h>
10 #include <asm/global_data.h>
11 #include <asm/io.h>
12 
13 DECLARE_GLOBAL_DATA_PTR;
14 
15 const ulong patterns[]      = {	0x00000000,
16 				0xFFFFFFFF,
17 				0xFF00FF00,
18 				0x0F0F0F0F,
19 				0xF0F0F0F0};
20 const ulong NBR_OF_PATTERNS = sizeof(patterns) / sizeof(*patterns);
21 const ulong OFFS_PATTERN    = 3;
22 const ulong REPEAT_PATTERN  = 1000;
23 
bootcount_store(ulong a)24 void bootcount_store(ulong a)
25 {
26 	ulong *save_addr;
27 	ulong size = 0;
28 	int i;
29 
30 	for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++)
31 		size += gd->bd->bi_dram[i].size;
32 	save_addr = (ulong *)(size - BOOTCOUNT_ADDR);
33 	writel(a, save_addr);
34 	writel(CONFIG_SYS_BOOTCOUNT_MAGIC, &save_addr[1]);
35 
36 	for (i = 0; i < REPEAT_PATTERN; i++)
37 		writel(patterns[i % NBR_OF_PATTERNS],
38 			&save_addr[i + OFFS_PATTERN]);
39 
40 	/* Make sure the data is written to RAM */
41 	flush_dcache_range((ulong)&save_addr[0],
42 			   (((ulong)&save_addr[REPEAT_PATTERN + OFFS_PATTERN] &
43 			     ~(ARCH_DMA_MINALIGN - 1)) + ARCH_DMA_MINALIGN));
44 }
45 
bootcount_load(void)46 ulong bootcount_load(void)
47 {
48 	ulong *save_addr;
49 	ulong size = 0;
50 	ulong counter = 0;
51 	int i, tmp;
52 
53 	for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++)
54 		size += gd->bd->bi_dram[i].size;
55 	save_addr = (ulong *)(size - BOOTCOUNT_ADDR);
56 
57 	counter = readl(&save_addr[0]);
58 
59 	/* Is the counter reliable, check in the big pattern for bit errors */
60 	for (i = 0; (i < REPEAT_PATTERN) && (counter != 0); i++) {
61 		tmp = readl(&save_addr[i + OFFS_PATTERN]);
62 		if (tmp != patterns[i % NBR_OF_PATTERNS])
63 			counter = 0;
64 	}
65 	return counter;
66 }
67