drivers/bootcount/bootcount_at91.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2
   3 #include <asm/io.h>
   4 #include <asm/arch/hardware.h>
   5 #include <asm/arch/at91_gpbr.h>
   6
   7 /*
   8  * We combine the CONFIG_SYS_BOOTCOUNT_MAGIC and bootcount in one 32-bit
   9  * register. This is done so we need to use only one of the four GPBR
  10  * registers.
  11  */
  12 void bootcount_store(ulong a)
  13 {
  14         at91_gpbr_t *gpbr = (at91_gpbr_t *) ATMEL_BASE_GPBR;
  15
  16         writel((CONFIG_SYS_BOOTCOUNT_MAGIC & 0xffff0000) | (a & 0x0000ffff),
  17                &gpbr->reg[AT91_GPBR_INDEX_BOOTCOUNT]);
  18 }
  19
  20 ulong bootcount_load(void)
  21 {
  22         at91_gpbr_t *gpbr = (at91_gpbr_t *) ATMEL_BASE_GPBR;
  23
  24         ulong val = readl(&gpbr->reg[AT91_GPBR_INDEX_BOOTCOUNT]);
  25         if ((val & 0xffff0000) != (CONFIG_SYS_BOOTCOUNT_MAGIC & 0xffff0000))
  26                 return 0;
  27         else
  28                 return val & 0x0000ffff;
  29 }