u-boot/drivers/bootcount/bootcount_ram.c
Marek Vasut 758694ff07 bootcount: Make bootcount magic configurable
Add new Kconfig option, SYS_BOOTCOUNT_MAGIC, to select the boot
counter magic word. This can be useful ie. in case the entire
boot counter register is not usable.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Tom Rini <trini@konsulko.com>
2018-10-19 14:16:43 -04:00

63 lines
1.5 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2010
* Heiko Schocher, DENX Software Engineering, hs@denx.de.
*/
#include <common.h>
#include <asm/io.h>
DECLARE_GLOBAL_DATA_PTR;
const ulong patterns[] = { 0x00000000,
0xFFFFFFFF,
0xFF00FF00,
0x0F0F0F0F,
0xF0F0F0F0};
const ulong NBR_OF_PATTERNS = sizeof(patterns) / sizeof(*patterns);
const ulong OFFS_PATTERN = 3;
const ulong REPEAT_PATTERN = 1000;
void bootcount_store(ulong a)
{
ulong *save_addr;
ulong size = 0;
int i;
for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++)
size += gd->bd->bi_dram[i].size;
save_addr = (ulong *)(size - BOOTCOUNT_ADDR);
writel(a, save_addr);
writel(CONFIG_SYS_BOOTCOUNT_MAGIC, &save_addr[1]);
for (i = 0; i < REPEAT_PATTERN; i++)
writel(patterns[i % NBR_OF_PATTERNS],
&save_addr[i + OFFS_PATTERN]);
/* Make sure the data is written to RAM */
flush_dcache_range((ulong)&save_addr[0],
(((ulong)&save_addr[REPEAT_PATTERN + OFFS_PATTERN] &
~(ARCH_DMA_MINALIGN - 1)) + ARCH_DMA_MINALIGN));
}
ulong bootcount_load(void)
{
ulong *save_addr;
ulong size = 0;
ulong counter = 0;
int i, tmp;
for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++)
size += gd->bd->bi_dram[i].size;
save_addr = (ulong *)(size - BOOTCOUNT_ADDR);
counter = readl(&save_addr[0]);
/* Is the counter reliable, check in the big pattern for bit errors */
for (i = 0; (i < REPEAT_PATTERN) && (counter != 0); i++) {
tmp = readl(&save_addr[i + OFFS_PATTERN]);
if (tmp != patterns[i % NBR_OF_PATTERNS])
counter = 0;
}
return counter;
}