LXR uboot/drivers/bootcount/bootcount

   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
  13DECLARE_GLOBAL_DATA_PTR;
  14
  15const ulong patterns[]      = { 0x00000000,
  16                                0xFFFFFFFF,
  17                                0xFF00FF00,
  18                                0x0F0F0F0F,
  19                                0xF0F0F0F0};
  20const ulong NBR_OF_PATTERNS = sizeof(patterns) / sizeof(*patterns);
  21const ulong OFFS_PATTERN    = 3;
  22const ulong REPEAT_PATTERN  = 1000;
  23
  24void 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
  46ulong 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