xref: /OK3568_Linux_fs/u-boot/drivers/bootcount/bootcount_ram.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * (C) Copyright 2010
3*4882a593Smuzhiyun  * Heiko Schocher, DENX Software Engineering, hs@denx.de.
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * SPDX-License-Identifier:	GPL-2.0+
6*4882a593Smuzhiyun  */
7*4882a593Smuzhiyun 
8*4882a593Smuzhiyun #include <common.h>
9*4882a593Smuzhiyun #include <asm/io.h>
10*4882a593Smuzhiyun 
11*4882a593Smuzhiyun DECLARE_GLOBAL_DATA_PTR;
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun const ulong patterns[]      = {	0x00000000,
14*4882a593Smuzhiyun 				0xFFFFFFFF,
15*4882a593Smuzhiyun 				0xFF00FF00,
16*4882a593Smuzhiyun 				0x0F0F0F0F,
17*4882a593Smuzhiyun 				0xF0F0F0F0};
18*4882a593Smuzhiyun const ulong NBR_OF_PATTERNS = sizeof(patterns) / sizeof(*patterns);
19*4882a593Smuzhiyun const ulong OFFS_PATTERN    = 3;
20*4882a593Smuzhiyun const ulong REPEAT_PATTERN  = 1000;
21*4882a593Smuzhiyun 
bootcount_store(ulong a)22*4882a593Smuzhiyun void bootcount_store(ulong a)
23*4882a593Smuzhiyun {
24*4882a593Smuzhiyun 	ulong *save_addr;
25*4882a593Smuzhiyun 	ulong size = 0;
26*4882a593Smuzhiyun 	int i;
27*4882a593Smuzhiyun 
28*4882a593Smuzhiyun 	for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++)
29*4882a593Smuzhiyun 		size += gd->bd->bi_dram[i].size;
30*4882a593Smuzhiyun 	save_addr = (ulong *)(size - BOOTCOUNT_ADDR);
31*4882a593Smuzhiyun 	writel(a, save_addr);
32*4882a593Smuzhiyun 	writel(BOOTCOUNT_MAGIC, &save_addr[1]);
33*4882a593Smuzhiyun 
34*4882a593Smuzhiyun 	for (i = 0; i < REPEAT_PATTERN; i++)
35*4882a593Smuzhiyun 		writel(patterns[i % NBR_OF_PATTERNS],
36*4882a593Smuzhiyun 			&save_addr[i + OFFS_PATTERN]);
37*4882a593Smuzhiyun 
38*4882a593Smuzhiyun 	/* Make sure the data is written to RAM */
39*4882a593Smuzhiyun 	flush_dcache_range((ulong)&save_addr[0],
40*4882a593Smuzhiyun 			   (((ulong)&save_addr[REPEAT_PATTERN + OFFS_PATTERN] &
41*4882a593Smuzhiyun 			     ~(ARCH_DMA_MINALIGN - 1)) + ARCH_DMA_MINALIGN));
42*4882a593Smuzhiyun }
43*4882a593Smuzhiyun 
bootcount_load(void)44*4882a593Smuzhiyun ulong bootcount_load(void)
45*4882a593Smuzhiyun {
46*4882a593Smuzhiyun 	ulong *save_addr;
47*4882a593Smuzhiyun 	ulong size = 0;
48*4882a593Smuzhiyun 	ulong counter = 0;
49*4882a593Smuzhiyun 	int i, tmp;
50*4882a593Smuzhiyun 
51*4882a593Smuzhiyun 	for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++)
52*4882a593Smuzhiyun 		size += gd->bd->bi_dram[i].size;
53*4882a593Smuzhiyun 	save_addr = (ulong *)(size - BOOTCOUNT_ADDR);
54*4882a593Smuzhiyun 
55*4882a593Smuzhiyun 	counter = readl(&save_addr[0]);
56*4882a593Smuzhiyun 
57*4882a593Smuzhiyun 	/* Is the counter reliable, check in the big pattern for bit errors */
58*4882a593Smuzhiyun 	for (i = 0; (i < REPEAT_PATTERN) && (counter != 0); i++) {
59*4882a593Smuzhiyun 		tmp = readl(&save_addr[i + OFFS_PATTERN]);
60*4882a593Smuzhiyun 		if (tmp != patterns[i % NBR_OF_PATTERNS])
61*4882a593Smuzhiyun 			counter = 0;
62*4882a593Smuzhiyun 	}
63*4882a593Smuzhiyun 	return counter;
64*4882a593Smuzhiyun }
65