hw/imx_ccm.c

   1 /*
   2  * IMX31 Clock Control Module
   3  *
   4  * Copyright (C) 2012 NICTA
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
   7  * See the COPYING file in the top-level directory.
   8  *
   9  * To get the timer frequencies right, we need to emulate at least part of
  10  * the CCM.
  11  */
  12
  13 #include "hw.h"
  14 #include "sysbus.h"
  15 #include "sysemu/sysemu.h"
  16 #include "imx.h"
  17
  18 #define CKIH_FREQ 26000000 /* 26MHz crystal input */
  19 #define CKIL_FREQ    32768 /* nominal 32khz clock */
  20
  21
  22 //#define DEBUG_CCM 1
  23 #ifdef DEBUG_CCM
  24 #define DPRINTF(fmt, args...) \
  25 do { printf("imx_ccm: " fmt , ##args); } while (0)
  26 #else
  27 #define DPRINTF(fmt, args...) do {} while (0)
  28 #endif
  29
  30 static int imx_ccm_post_load(void *opaque, int version_id);
  31
  32 typedef struct {
  33     SysBusDevice busdev;
  34     MemoryRegion iomem;
  35
  36     uint32_t ccmr;
  37     uint32_t pdr0;
  38     uint32_t pdr1;
  39     uint32_t mpctl;
  40     uint32_t spctl;
  41     uint32_t cgr[3];
  42     uint32_t pmcr0;
  43     uint32_t pmcr1;
  44
  45     /* Frequencies precalculated on register changes */
  46     uint32_t pll_refclk_freq;
  47     uint32_t mcu_clk_freq;
  48     uint32_t hsp_clk_freq;
  49     uint32_t ipg_clk_freq;
  50 } IMXCCMState;
  51
  52 static const VMStateDescription vmstate_imx_ccm = {
  53     .name = "imx-ccm",
  54     .version_id = 1,
  55     .minimum_version_id = 1,
  56     .minimum_version_id_old = 1,
  57     .fields = (VMStateField[]) {
  58         VMSTATE_UINT32(ccmr, IMXCCMState),
  59         VMSTATE_UINT32(pdr0, IMXCCMState),
  60         VMSTATE_UINT32(pdr1, IMXCCMState),
  61         VMSTATE_UINT32(mpctl, IMXCCMState),
  62         VMSTATE_UINT32(spctl, IMXCCMState),
  63         VMSTATE_UINT32_ARRAY(cgr, IMXCCMState, 3),
  64         VMSTATE_UINT32(pmcr0, IMXCCMState),
  65         VMSTATE_UINT32(pmcr1, IMXCCMState),
  66         VMSTATE_UINT32(pll_refclk_freq, IMXCCMState),
  67     },
  68     .post_load = imx_ccm_post_load,
  69 };
  70
  71 /* CCMR */
  72 #define CCMR_FPME (1<<0)
  73 #define CCMR_MPE  (1<<3)
  74 #define CCMR_MDS  (1<<7)
  75 #define CCMR_FPMF (1<<26)
  76 #define CCMR_PRCS (3<<1)
  77
  78 /* PDR0 */
  79 #define PDR0_MCU_PODF_SHIFT (0)
  80 #define PDR0_MCU_PODF_MASK (0x7)
  81 #define PDR0_MAX_PODF_SHIFT (3)
  82 #define PDR0_MAX_PODF_MASK (0x7)
  83 #define PDR0_IPG_PODF_SHIFT (6)
  84 #define PDR0_IPG_PODF_MASK (0x3)
  85 #define PDR0_NFC_PODF_SHIFT (8)
  86 #define PDR0_NFC_PODF_MASK (0x7)
  87 #define PDR0_HSP_PODF_SHIFT (11)
  88 #define PDR0_HSP_PODF_MASK (0x7)
  89 #define PDR0_PER_PODF_SHIFT (16)
  90 #define PDR0_PER_PODF_MASK (0x1f)
  91 #define PDR0_CSI_PODF_SHIFT (23)
  92 #define PDR0_CSI_PODF_MASK (0x1ff)
  93
  94 #define EXTRACT(value, name) (((value) >> PDR0_##name##_PODF_SHIFT) \
  95                               & PDR0_##name##_PODF_MASK)
  96 #define INSERT(value, name) (((value) & PDR0_##name##_PODF_MASK) << \
  97                              PDR0_##name##_PODF_SHIFT)
  98 /* PLL control registers */
  99 #define PD(v) (((v) >> 26) & 0xf)
 100 #define MFD(v) (((v) >> 16) & 0x3ff)
 101 #define MFI(v) (((v) >> 10) & 0xf);
 102 #define MFN(v) ((v) & 0x3ff)
 103
 104 #define PLL_PD(x)               (((x) & 0xf) << 26)
 105 #define PLL_MFD(x)              (((x) & 0x3ff) << 16)
 106 #define PLL_MFI(x)              (((x) & 0xf) << 10)
 107 #define PLL_MFN(x)              (((x) & 0x3ff) << 0)
 108
 109 uint32_t imx_clock_frequency(DeviceState *dev, IMXClk clock)
 110 {
 111     IMXCCMState *s = container_of(dev, IMXCCMState, busdev.qdev);
 112
 113     switch (clock) {
 114     case NOCLK:
 115         return 0;
 116     case MCU:
 117         return s->mcu_clk_freq;
 118     case HSP:
 119         return s->hsp_clk_freq;
 120     case IPG:
 121         return s->ipg_clk_freq;
 122     case CLK_32k:
 123         return CKIL_FREQ;
 124     }
 125     return 0;
 126 }
 127
 128 /*
 129  * Calculate PLL output frequency
 130  */
 131 static uint32_t calc_pll(uint32_t pllreg, uint32_t base_freq)
 132 {
 133     int32_t mfn = MFN(pllreg);  /* Numerator */
 134     uint32_t mfi = MFI(pllreg); /* Integer part */
 135     uint32_t mfd = 1 + MFD(pllreg); /* Denominator */
 136     uint32_t pd = 1 + PD(pllreg);   /* Pre-divider */
 137
 138     if (mfi < 5) {
 139         mfi = 5;
 140     }
 141     /* mfn is 10-bit signed twos-complement */
 142     mfn <<= 32 - 10;
 143     mfn >>= 32 - 10;
 144
 145     return ((2 * (base_freq >> 10) * (mfi * mfd + mfn)) /
 146             (mfd * pd)) << 10;
 147 }
 148
 149 static void update_clocks(IMXCCMState *s)
 150 {
 151     /*
 152      * If we ever emulate more clocks, this should switch to a data-driven
 153      * approach
 154      */
 155
 156     if ((s->ccmr & CCMR_PRCS) == 1) {
 157         s->pll_refclk_freq = CKIL_FREQ * 1024;
 158     } else {
 159         s->pll_refclk_freq = CKIH_FREQ;
 160     }
 161
 162     /* ipg_clk_arm aka MCU clock */
 163     if ((s->ccmr & CCMR_MDS) || !(s->ccmr & CCMR_MPE)) {
 164         s->mcu_clk_freq = s->pll_refclk_freq;
 165     } else {
 166         s->mcu_clk_freq = calc_pll(s->mpctl, s->pll_refclk_freq);
 167     }
 168
 169     /* High-speed clock */
 170     s->hsp_clk_freq = s->mcu_clk_freq / (1 + EXTRACT(s->pdr0, HSP));
 171     s->ipg_clk_freq = s->hsp_clk_freq / (1 + EXTRACT(s->pdr0, IPG));
 172
 173     DPRINTF("Clocks: mcu %uMHz, HSP %uMHz, IPG %uHz\n",
 174             s->mcu_clk_freq / 1000000,
 175             s->hsp_clk_freq / 1000000,
 176             s->ipg_clk_freq);
 177 }
 178
 179 static void imx_ccm_reset(DeviceState *dev)
 180 {
 181     IMXCCMState *s = container_of(dev, IMXCCMState, busdev.qdev);
 182
 183     s->ccmr = 0x074b0b7b;
 184     s->pdr0 = 0xff870b48;
 185     s->pdr1 = 0x49fcfe7f;
 186     s->mpctl = PLL_PD(1) | PLL_MFD(0) | PLL_MFI(6) | PLL_MFN(0);
 187     s->cgr[0] = s->cgr[1] = s->cgr[2] = 0xffffffff;
 188     s->spctl = PLL_PD(1) | PLL_MFD(4) | PLL_MFI(0xc) | PLL_MFN(1);
 189     s->pmcr0 = 0x80209828;
 190
 191     update_clocks(s);
 192 }
 193
 194 static uint64_t imx_ccm_read(void *opaque, hwaddr offset,
 195                                 unsigned size)
 196 {
 197     IMXCCMState *s = (IMXCCMState *)opaque;
 198
 199     DPRINTF("read(offset=%x)", offset >> 2);
 200     switch (offset >> 2) {
 201     case 0: /* CCMR */
 202         DPRINTF(" ccmr = 0x%x\n", s->ccmr);
 203         return s->ccmr;
 204     case 1:
 205         DPRINTF(" pdr0 = 0x%x\n", s->pdr0);
 206         return s->pdr0;
 207     case 2:
 208         DPRINTF(" pdr1 = 0x%x\n", s->pdr1);
 209         return s->pdr1;
 210     case 4:
 211         DPRINTF(" mpctl = 0x%x\n", s->mpctl);
 212         return s->mpctl;
 213     case 6:
 214         DPRINTF(" spctl = 0x%x\n", s->spctl);
 215         return s->spctl;
 216     case 8:
 217         DPRINTF(" cgr0 = 0x%x\n", s->cgr[0]);
 218         return s->cgr[0];
 219     case 9:
 220         DPRINTF(" cgr1 = 0x%x\n", s->cgr[1]);
 221         return s->cgr[1];
 222     case 10:
 223         DPRINTF(" cgr2 = 0x%x\n", s->cgr[2]);
 224         return s->cgr[2];
 225     case 18: /* LTR1 */
 226         return 0x00004040;
 227     case 23:
 228         DPRINTF(" pcmr0 = 0x%x\n", s->pmcr0);
 229         return s->pmcr0;
 230     }
 231     DPRINTF(" return 0\n");
 232     return 0;
 233 }
 234
 235 static void imx_ccm_write(void *opaque, hwaddr offset,
 236                           uint64_t value, unsigned size)
 237 {
 238     IMXCCMState *s = (IMXCCMState *)opaque;
 239
 240     DPRINTF("write(offset=%x, value = %x)\n",
 241             offset >> 2, (unsigned int)value);
 242     switch (offset >> 2) {
 243     case 0:
 244         s->ccmr = CCMR_FPMF | (value & 0x3b6fdfff);
 245         break;
 246     case 1:
 247         s->pdr0 = value & 0xff9f3fff;
 248         break;
 249     case 2:
 250         s->pdr1 = value;
 251         break;
 252     case 4:
 253         s->mpctl = value & 0xbfff3fff;
 254         break;
 255     case 6:
 256         s->spctl = value & 0xbfff3fff;
 257         break;
 258     case 8:
 259         s->cgr[0] = value;
 260         return;
 261     case 9:
 262         s->cgr[1] = value;
 263         return;
 264     case 10:
 265         s->cgr[2] = value;
 266         return;
 267
 268     default:
 269         return;
 270     }
 271     update_clocks(s);
 272 }
 273
 274 static const struct MemoryRegionOps imx_ccm_ops = {
 275     .read = imx_ccm_read,
 276     .write = imx_ccm_write,
 277     .endianness = DEVICE_NATIVE_ENDIAN,
 278 };
 279
 280 static int imx_ccm_init(SysBusDevice *dev)
 281 {
 282     IMXCCMState *s = FROM_SYSBUS(typeof(*s), dev);
 283
 284     memory_region_init_io(&s->iomem, &imx_ccm_ops, s, "imx_ccm", 0x1000);
 285     sysbus_init_mmio(dev, &s->iomem);
 286
 287     return 0;
 288 }
 289
 290 static int imx_ccm_post_load(void *opaque, int version_id)
 291 {
 292     IMXCCMState *s = (IMXCCMState *)opaque;
 293
 294     update_clocks(s);
 295     return 0;
 296 }
 297
 298 static void imx_ccm_class_init(ObjectClass *klass, void *data)
 299 {
 300     DeviceClass *dc = DEVICE_CLASS(klass);
 301     SysBusDeviceClass *sbc = SYS_BUS_DEVICE_CLASS(klass);
 302
 303     sbc->init = imx_ccm_init;
 304     dc->reset = imx_ccm_reset;
 305     dc->vmsd = &vmstate_imx_ccm;
 306     dc->desc = "i.MX Clock Control Module";
 307 }
 308
 309 static TypeInfo imx_ccm_info = {
 310     .name = "imx_ccm",
 311     .parent = TYPE_SYS_BUS_DEVICE,
 312     .instance_size = sizeof(IMXCCMState),
 313     .class_init = imx_ccm_class_init,
 314 };
 315
 316 static void imx_ccm_register_types(void)
 317 {
 318     type_register_static(&imx_ccm_info);
 319 }
 320
 321 type_init(imx_ccm_register_types)