plat/st/stm32mp1/stm32mp1_context.c

   1 /*
   2  * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
   3  *
   4  * SPDX-License-Identifier: BSD-3-Clause
   5  */
   6
   7 #include <dt-bindings/clock/stm32mp1-clks.h>
   8 #include <errno.h>
   9 #include <mmio.h>
  10 #include <platform_def.h>
  11 #include <stm32mp1_clk.h>
  12 #include <stm32mp1_context.h>
  13
  14 #define TAMP_BOOT_ITF_BACKUP_REG_ID     U(20)
  15 #define TAMP_BOOT_ITF_MASK              U(0x0000FF00)
  16 #define TAMP_BOOT_ITF_SHIFT             8
  17
  18 int stm32_save_boot_interface(uint32_t interface, uint32_t instance)
  19 {
  20         uint32_t tamp_clk_off = 0;
  21         uint32_t bkpr_itf_idx = tamp_bkpr(TAMP_BOOT_ITF_BACKUP_REG_ID);
  22
  23         if (!stm32mp1_clk_is_enabled(RTCAPB)) {
  24                 tamp_clk_off = 1;
  25                 if (stm32mp1_clk_enable(RTCAPB) != 0) {
  26                         return -EINVAL;
  27                 }
  28         }
  29
  30         mmio_clrsetbits_32(bkpr_itf_idx,
  31                            TAMP_BOOT_ITF_MASK,
  32                            ((interface << 4) | (instance & 0xFU)) <<
  33                            TAMP_BOOT_ITF_SHIFT);
  34
  35         if (tamp_clk_off != 0U) {
  36                 if (stm32mp1_clk_disable(RTCAPB) != 0) {
  37                         return -EINVAL;
  38                 }
  39         }
  40
  41         return 0;
  42 }