LXR linux/arch/arm/mach-imx/cpu-imx25.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * MX25 CPU type detection
   4 *
   5 * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
   6 * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved
   7 */
   8#include <linux/module.h>
   9#include <linux/io.h>
  10#include <linux/of.h>
  11#include <linux/of_address.h>
  12
  13#include "iim.h"
  14#include "hardware.h"
  15
  16static int mx25_cpu_rev = -1;
  17
  18static int mx25_read_cpu_rev(void)
  19{
  20        u32 rev;
  21        void __iomem *iim_base;
  22        struct device_node *np;
  23
  24        np = of_find_compatible_node(NULL, NULL, "fsl,imx25-iim");
  25        iim_base = of_iomap(np, 0);
  26        BUG_ON(!iim_base);
  27        rev = readl(iim_base + MXC_IIMSREV);
  28        iounmap(iim_base);
  29
  30        switch (rev) {
  31        case 0x00:
  32                return IMX_CHIP_REVISION_1_0;
  33        case 0x01:
  34                return IMX_CHIP_REVISION_1_1;
  35        default:
  36                return IMX_CHIP_REVISION_UNKNOWN;
  37        }
  38}
  39
  40int mx25_revision(void)
  41{
  42        if (mx25_cpu_rev == -1)
  43                mx25_cpu_rev = mx25_read_cpu_rev();
  44
  45        return mx25_cpu_rev;
  46}
  47EXPORT_SYMBOL(mx25_revision);
  48