diff --git a/board/keymile/km_arm/km_arm.c b/board/keymile/km_arm/km_arm.c index 3c9b917..ca33aae 100644 --- a/board/keymile/km_arm/km_arm.c +++ b/board/keymile/km_arm/km_arm.c @@ -405,6 +405,15 @@ int hush_init_var(void) #endif #if defined(CONFIG_BOOTCOUNT_LIMIT) +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) { volatile ulong *save_addr; @@ -416,21 +425,34 @@ void bootcount_store(ulong a) save_addr = (ulong*)(size - BOOTCOUNT_ADDR); writel(a, save_addr); writel(BOOTCOUNT_MAGIC, &save_addr[1]); + + for (i = 0; i < REPEAT_PATTERN; i++) + writel(patterns[i % NBR_OF_PATTERNS], + &save_addr[i+OFFS_PATTERN]); + } ulong bootcount_load(void) { volatile ulong *save_addr; volatile ulong size = 0; - int i; + 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); - if (readl(&save_addr[1]) != BOOTCOUNT_MAGIC) - return 0; - else - return readl(save_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; } #endif