LXR uboot/arch/x86/lib/early

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Copyright (C) 2017, Bin Meng <bmeng.cn@gmail.com>
   4 */
   5
   6/*
   7 * This library provides CMOS (inside RTC SRAM) access routines at a very
   8 * early stage when driver model is not available yet. Only read access is
   9 * provided. The 16-bit/32-bit read are compatible with driver model RTC
  10 * uclass write ops, that data is stored in little-endian mode.
  11 */
  12
  13#include <common.h>
  14#include <asm/early_cmos.h>
  15#include <asm/io.h>
  16
  17u8 cmos_read8(u8 addr)
  18{
  19        outb(addr, CMOS_IO_PORT);
  20
  21        return inb(CMOS_IO_PORT + 1);
  22}
  23
  24u16 cmos_read16(u8 addr)
  25{
  26        u16 value = 0;
  27        u16 data;
  28        int i;
  29
  30        for (i = 0; i < sizeof(value); i++) {
  31                data = cmos_read8(addr + i);
  32                value |= data << (i << 3);
  33        }
  34
  35        return value;
  36}
  37
  38u32 cmos_read32(u8 addr)
  39{
  40        u32 value = 0;
  41        u32 data;
  42        int i;
  43
  44        for (i = 0; i < sizeof(value); i++) {
  45                data = cmos_read8(addr + i);
  46                value |= data << (i << 3);
  47        }
  48
  49        return value;
  50}
  51