LXR uboot/drivers/bootcount/bootcount

   1/*
   2 * (C) Copyright 2011
   3 * Heiko Schocher, DENX Software Engineering, hs@denx.de.
   4 *
   5 * A bootcount driver for the RTC IP block found on many TI platforms.
   6 * This requires the RTC clocks, etc, to be enabled prior to use and
   7 * not all boards with this IP block on it will have the RTC in use.
   8 *
   9 * SPDX-License-Identifier:     GPL-2.0+
  10 */
  11
  12#include <bootcount.h>
  13#include <asm/davinci_rtc.h>
  14
  15void bootcount_store(ulong a)
  16{
  17        struct davinci_rtc *reg =
  18                (struct davinci_rtc *)CONFIG_SYS_BOOTCOUNT_ADDR;
  19
  20        /*
  21         * write RTC kick register to enable write
  22         * for RTC Scratch registers. Scratch0 and 1 are
  23         * used for bootcount values.
  24         */
  25        writel(RTC_KICK0R_WE, &reg->kick0r);
  26        writel(RTC_KICK1R_WE, &reg->kick1r);
  27        raw_bootcount_store(&reg->scratch2,
  28                            (BOOTCOUNT_MAGIC & 0xffff0000) | (a & 0x0000ffff));
  29}
  30
  31ulong bootcount_load(void)
  32{
  33        unsigned long val;
  34        struct davinci_rtc *reg =
  35                (struct davinci_rtc *)CONFIG_SYS_BOOTCOUNT_ADDR;
  36
  37        val = raw_bootcount_load(&reg->scratch2);
  38        if ((val & 0xffff0000) != (BOOTCOUNT_MAGIC & 0xffff0000))
  39                return 0;
  40        else
  41                return val & 0x0000ffff;
  42}
  43