LXR qemu/hw/misc/imx

   1/*
   2 * IMX31 Clock Control Module
   3 *
   4 * Copyright (C) 2012 NICTA
   5 * Updated by Jean-Christophe Dubois <jcd@tribudubois.net>
   6 *
   7 * This work is licensed under the terms of the GNU GPL, version 2 or later.
   8 * See the COPYING file in the top-level directory.
   9 *
  10 * This is an abstract base class used to get a common interface to
  11 * retrieve the CCM frequencies from the various i.MX SOC.
  12 */
  13
  14#include "qemu/osdep.h"
  15#include "hw/misc/imx_ccm.h"
  16
  17#ifndef DEBUG_IMX_CCM
  18#define DEBUG_IMX_CCM 0
  19#endif
  20
  21#define DPRINTF(fmt, args...) \
  22    do { \
  23        if (DEBUG_IMX_CCM) { \
  24            fprintf(stderr, "[%s]%s: " fmt , TYPE_IMX_CCM, \
  25                                             __func__, ##args); \
  26        } \
  27    } while (0)
  28
  29
  30uint32_t imx_ccm_get_clock_frequency(IMXCCMState *dev, IMXClk clock)
  31{
  32    uint32_t freq = 0;
  33    IMXCCMClass *klass = IMX_GET_CLASS(dev);
  34
  35    if (klass->get_clock_frequency) {
  36        freq = klass->get_clock_frequency(dev, clock);
  37    }
  38
  39    DPRINTF("(clock = %d) = %d\n", clock, freq);
  40
  41    return freq;
  42}
  43
  44/*
  45 * Calculate PLL output frequency
  46 */
  47uint32_t imx_ccm_calc_pll(uint32_t pllreg, uint32_t base_freq)
  48{
  49    int32_t freq;
  50    int32_t mfn = MFN(pllreg);  /* Numerator */
  51    uint32_t mfi = MFI(pllreg); /* Integer part */
  52    uint32_t mfd = 1 + MFD(pllreg); /* Denominator */
  53    uint32_t pd = 1 + PD(pllreg);   /* Pre-divider */
  54
  55    if (mfi < 5) {
  56        mfi = 5;
  57    }
  58
  59    /* mfn is 10-bit signed twos-complement */
  60    mfn <<= 32 - 10;
  61    mfn >>= 32 - 10;
  62
  63    freq = ((2 * (base_freq >> 10) * (mfi * mfd + mfn)) /
  64            (mfd * pd)) << 10;
  65
  66    DPRINTF("(pllreg = 0x%08x, base_freq = %d) = %d\n", pllreg, base_freq,
  67            freq);
  68
  69    return freq;
  70}
  71
  72static const TypeInfo imx_ccm_info = {
  73    .name          = TYPE_IMX_CCM,
  74    .parent        = TYPE_SYS_BUS_DEVICE,
  75    .instance_size = sizeof(IMXCCMState),
  76    .class_size    = sizeof(IMXCCMClass),
  77    .abstract      = true,
  78};
  79
  80static void imx_ccm_register_types(void)
  81{
  82    type_register_static(&imx_ccm_info);
  83}
  84
  85type_init(imx_ccm_register_types)
  86