LXR linux/arch/arm/mach-imx/cpu-imx31.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * MX31 CPU type detection
   4 *
   5 * Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
   6 */
   7
   8#include <linux/module.h>
   9#include <linux/of_address.h>
  10#include <linux/io.h>
  11
  12#include "common.h"
  13#include "hardware.h"
  14#include "iim.h"
  15
  16static int mx31_cpu_rev = -1;
  17
  18static struct {
  19        u8 srev;
  20        const char *name;
  21        unsigned int rev;
  22} mx31_cpu_type[] = {
  23        { .srev = 0x00, .name = "i.MX31(L)", .rev = IMX_CHIP_REVISION_1_0 },
  24        { .srev = 0x10, .name = "i.MX31",    .rev = IMX_CHIP_REVISION_1_1 },
  25        { .srev = 0x11, .name = "i.MX31L",   .rev = IMX_CHIP_REVISION_1_1 },
  26        { .srev = 0x12, .name = "i.MX31",    .rev = IMX_CHIP_REVISION_1_1 },
  27        { .srev = 0x13, .name = "i.MX31L",   .rev = IMX_CHIP_REVISION_1_1 },
  28        { .srev = 0x14, .name = "i.MX31",    .rev = IMX_CHIP_REVISION_1_2 },
  29        { .srev = 0x15, .name = "i.MX31L",   .rev = IMX_CHIP_REVISION_1_2 },
  30        { .srev = 0x28, .name = "i.MX31",    .rev = IMX_CHIP_REVISION_2_0 },
  31        { .srev = 0x29, .name = "i.MX31L",   .rev = IMX_CHIP_REVISION_2_0 },
  32};
  33
  34static int mx31_read_cpu_rev(void)
  35{
  36        void __iomem *iim_base;
  37        struct device_node *np;
  38        u32 i, srev;
  39
  40        np = of_find_compatible_node(NULL, NULL, "fsl,imx31-iim");
  41        iim_base = of_iomap(np, 0);
  42        BUG_ON(!iim_base);
  43
  44        /* read SREV register from IIM module */
  45        srev = imx_readl(iim_base + MXC_IIMSREV);
  46        srev &= 0xff;
  47
  48        for (i = 0; i < ARRAY_SIZE(mx31_cpu_type); i++)
  49                if (srev == mx31_cpu_type[i].srev) {
  50                        imx_print_silicon_rev(mx31_cpu_type[i].name,
  51                                                mx31_cpu_type[i].rev);
  52                        return mx31_cpu_type[i].rev;
  53                }
  54
  55        imx_print_silicon_rev("i.MX31", IMX_CHIP_REVISION_UNKNOWN);
  56        return IMX_CHIP_REVISION_UNKNOWN;
  57}
  58
  59int mx31_revision(void)
  60{
  61        if (mx31_cpu_rev == -1)
  62                mx31_cpu_rev = mx31_read_cpu_rev();
  63
  64        return mx31_cpu_rev;
  65}
  66EXPORT_SYMBOL(mx31_revision);
  67