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#include "qemu/log.h"
  17#include "qemu/module.h"
  18
  19#ifndef DEBUG_IMX_CCM
  20#define DEBUG_IMX_CCM 0
  21#endif
  22
  23#define DPRINTF(fmt, args...) \
  24    do { \
  25        if (DEBUG_IMX_CCM) { \
  26            fprintf(stderr, "[%s]%s: " fmt , TYPE_IMX_CCM, \
  27                                             __func__, ##args); \
  28        } \
  29    } while (0)
  30
  31
  32uint32_t imx_ccm_get_clock_frequency(IMXCCMState *dev, IMXClk clock)
  33{
  34    uint32_t freq = 0;
  35    IMXCCMClass *klass = IMX_GET_CLASS(dev);
  36
  37    if (klass->get_clock_frequency) {
  38        freq = klass->get_clock_frequency(dev, clock);
  39    }
  40
  41    DPRINTF("(clock = %d) = %d\n", clock, freq);
  42
  43    return freq;
  44}
  45
  46/*
  47 * Calculate PLL output frequency
  48 */
  49uint32_t imx_ccm_calc_pll(uint32_t pllreg, uint32_t base_freq)
  50{
  51    int32_t freq;
  52    int32_t mfn = MFN(pllreg);  /* Numerator */
  53    uint32_t mfi = MFI(pllreg); /* Integer part */
  54    uint32_t mfd = 1 + MFD(pllreg); /* Denominator */
  55    uint32_t pd = 1 + PD(pllreg);   /* Pre-divider */
  56
  57    if (mfi < 5) {
  58        mfi = 5;
  59    }
  60
  61    /* mfn is 10-bit signed twos-complement */
  62    mfn <<= 32 - 10;
  63    mfn >>= 32 - 10;
  64
  65    freq = ((2 * (base_freq >> 10) * (mfi * mfd + mfn)) /
  66            (mfd * pd)) << 10;
  67
  68    DPRINTF("(pllreg = 0x%08x, base_freq = %d) = %d\n", pllreg, base_freq,
  69            freq);
  70
  71    return freq;
  72}
  73
  74static const TypeInfo imx_ccm_info = {
  75    .name          = TYPE_IMX_CCM,
  76    .parent        = TYPE_SYS_BUS_DEVICE,
  77    .instance_size = sizeof(IMXCCMState),
  78    .class_size    = sizeof(IMXCCMClass),
  79    .abstract      = true,
  80};
  81
  82static void imx_ccm_register_types(void)
  83{
  84    type_register_static(&imx_ccm_info);
  85}
  86
  87type_init(imx_ccm_register_types)
  88