hw/misc/imx25_ccm.c

   1 /*
   2  * IMX25 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  * To get the timer frequencies right, we need to emulate at least part of
  11  * the CCM.
  12  */
  13
  14 #include "qemu/osdep.h"
  15 #include "hw/misc/imx25_ccm.h"
  16 #include "migration/vmstate.h"
  17 #include "qemu/log.h"
  18 #include "qemu/module.h"
  19
  20 #ifndef DEBUG_IMX25_CCM
  21 #define DEBUG_IMX25_CCM 0
  22 #endif
  23
  24 #define DPRINTF(fmt, args...) \
  25     do { \
  26         if (DEBUG_IMX25_CCM) { \
  27             fprintf(stderr, "[%s]%s: " fmt , TYPE_IMX25_CCM, \
  28                                              __func__, ##args); \
  29         } \
  30     } while (0)
  31
  32 static const char *imx25_ccm_reg_name(uint32_t reg)
  33 {
  34     static char unknown[20];
  35
  36     switch (reg) {
  37     case IMX25_CCM_MPCTL_REG:
  38         return "mpctl";
  39     case IMX25_CCM_UPCTL_REG:
  40         return "upctl";
  41     case IMX25_CCM_CCTL_REG:
  42         return "cctl";
  43     case IMX25_CCM_CGCR0_REG:
  44         return "cgcr0";
  45     case IMX25_CCM_CGCR1_REG:
  46         return "cgcr1";
  47     case IMX25_CCM_CGCR2_REG:
  48         return "cgcr2";
  49     case IMX25_CCM_PCDR0_REG:
  50         return "pcdr0";
  51     case IMX25_CCM_PCDR1_REG:
  52         return "pcdr1";
  53     case IMX25_CCM_PCDR2_REG:
  54         return "pcdr2";
  55     case IMX25_CCM_PCDR3_REG:
  56         return "pcdr3";
  57     case IMX25_CCM_RCSR_REG:
  58         return "rcsr";
  59     case IMX25_CCM_CRDR_REG:
  60         return "crdr";
  61     case IMX25_CCM_DCVR0_REG:
  62         return "dcvr0";
  63     case IMX25_CCM_DCVR1_REG:
  64         return "dcvr1";
  65     case IMX25_CCM_DCVR2_REG:
  66         return "dcvr2";
  67     case IMX25_CCM_DCVR3_REG:
  68         return "dcvr3";
  69     case IMX25_CCM_LTR0_REG:
  70         return "ltr0";
  71     case IMX25_CCM_LTR1_REG:
  72         return "ltr1";
  73     case IMX25_CCM_LTR2_REG:
  74         return "ltr2";
  75     case IMX25_CCM_LTR3_REG:
  76         return "ltr3";
  77     case IMX25_CCM_LTBR0_REG:
  78         return "ltbr0";
  79     case IMX25_CCM_LTBR1_REG:
  80         return "ltbr1";
  81     case IMX25_CCM_PMCR0_REG:
  82         return "pmcr0";
  83     case IMX25_CCM_PMCR1_REG:
  84         return "pmcr1";
  85     case IMX25_CCM_PMCR2_REG:
  86         return "pmcr2";
  87     case IMX25_CCM_MCR_REG:
  88         return "mcr";
  89     case IMX25_CCM_LPIMR0_REG:
  90         return "lpimr0";
  91     case IMX25_CCM_LPIMR1_REG:
  92         return "lpimr1";
  93     default:
  94         sprintf(unknown, "[%d ?]", reg);
  95         return unknown;
  96     }
  97 }
  98 #define CKIH_FREQ 24000000 /* 24MHz crystal input */
  99
 100 static const VMStateDescription vmstate_imx25_ccm = {
 101     .name = TYPE_IMX25_CCM,
 102     .version_id = 1,
 103     .minimum_version_id = 1,
 104     .fields = (VMStateField[]) {
 105         VMSTATE_UINT32_ARRAY(reg, IMX25CCMState, IMX25_CCM_MAX_REG),
 106         VMSTATE_END_OF_LIST()
 107     },
 108 };
 109
 110 static uint32_t imx25_ccm_get_mpll_clk(IMXCCMState *dev)
 111 {
 112     uint32_t freq;
 113     IMX25CCMState *s = IMX25_CCM(dev);
 114
 115     if (EXTRACT(s->reg[IMX25_CCM_CCTL_REG], MPLL_BYPASS)) {
 116         freq = CKIH_FREQ;
 117     } else {
 118         freq = imx_ccm_calc_pll(s->reg[IMX25_CCM_MPCTL_REG], CKIH_FREQ);
 119     }
 120
 121     DPRINTF("freq = %d\n", freq);
 122
 123     return freq;
 124 }
 125
 126 static uint32_t imx25_ccm_get_mcu_clk(IMXCCMState *dev)
 127 {
 128     uint32_t freq;
 129     IMX25CCMState *s = IMX25_CCM(dev);
 130
 131     freq = imx25_ccm_get_mpll_clk(dev);
 132
 133     if (EXTRACT(s->reg[IMX25_CCM_CCTL_REG], ARM_SRC)) {
 134         freq = (freq * 3 / 4);
 135     }
 136
 137     freq = freq / (1 + EXTRACT(s->reg[IMX25_CCM_CCTL_REG], ARM_CLK_DIV));
 138
 139     DPRINTF("freq = %d\n", freq);
 140
 141     return freq;
 142 }
 143
 144 static uint32_t imx25_ccm_get_ahb_clk(IMXCCMState *dev)
 145 {
 146     uint32_t freq;
 147     IMX25CCMState *s = IMX25_CCM(dev);
 148
 149     freq = imx25_ccm_get_mcu_clk(dev)
 150            / (1 + EXTRACT(s->reg[IMX25_CCM_CCTL_REG], AHB_CLK_DIV));
 151
 152     DPRINTF("freq = %d\n", freq);
 153
 154     return freq;
 155 }
 156
 157 static uint32_t imx25_ccm_get_ipg_clk(IMXCCMState *dev)
 158 {
 159     uint32_t freq;
 160
 161     freq = imx25_ccm_get_ahb_clk(dev) / 2;
 162
 163     DPRINTF("freq = %d\n", freq);
 164
 165     return freq;
 166 }
 167
 168 static uint32_t imx25_ccm_get_clock_frequency(IMXCCMState *dev, IMXClk clock)
 169 {
 170     uint32_t freq = 0;
 171     DPRINTF("Clock = %d)\n", clock);
 172
 173     switch (clock) {
 174     case CLK_NONE:
 175         break;
 176     case CLK_IPG:
 177     case CLK_IPG_HIGH:
 178         freq = imx25_ccm_get_ipg_clk(dev);
 179         break;
 180     case CLK_32k:
 181         freq = CKIL_FREQ;
 182         break;
 183     default:
 184         qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: unsupported clock %d\n",
 185                       TYPE_IMX25_CCM, __func__, clock);
 186         break;
 187     }
 188
 189     DPRINTF("Clock = %d) = %d\n", clock, freq);
 190
 191     return freq;
 192 }
 193
 194 static void imx25_ccm_reset(DeviceState *dev)
 195 {
 196     IMX25CCMState *s = IMX25_CCM(dev);
 197
 198     DPRINTF("\n");
 199
 200     memset(s->reg, 0, IMX25_CCM_MAX_REG * sizeof(uint32_t));
 201     s->reg[IMX25_CCM_MPCTL_REG] = 0x800b2c01;
 202     s->reg[IMX25_CCM_UPCTL_REG] = 0x84042800;
 203     /*
 204      * The value below gives:
 205      * CPU = 133 MHz, AHB = 66,5 MHz, IPG = 33 MHz.
 206      */
 207     s->reg[IMX25_CCM_CCTL_REG]  = 0xd0030000;
 208     s->reg[IMX25_CCM_CGCR0_REG] = 0x028A0100;
 209     s->reg[IMX25_CCM_CGCR1_REG] = 0x04008100;
 210     s->reg[IMX25_CCM_CGCR2_REG] = 0x00000438;
 211     s->reg[IMX25_CCM_PCDR0_REG] = 0x01010101;
 212     s->reg[IMX25_CCM_PCDR1_REG] = 0x01010101;
 213     s->reg[IMX25_CCM_PCDR2_REG] = 0x01010101;
 214     s->reg[IMX25_CCM_PCDR3_REG] = 0x01010101;
 215     s->reg[IMX25_CCM_PMCR0_REG] = 0x00A00000;
 216     s->reg[IMX25_CCM_PMCR1_REG] = 0x0000A030;
 217     s->reg[IMX25_CCM_PMCR2_REG] = 0x0000A030;
 218     s->reg[IMX25_CCM_MCR_REG]   = 0x43000000;
 219
 220     /*
 221      * default boot will change the reset values to allow:
 222      * CPU = 399 MHz, AHB = 133 MHz, IPG = 66,5 MHz.
 223      * For some reason, this doesn't work. With the value below, linux
 224      * detects a 88 MHz IPG CLK instead of 66,5 MHz.
 225     s->reg[IMX25_CCM_CCTL_REG]  = 0x20032000;
 226      */
 227 }
 228
 229 static uint64_t imx25_ccm_read(void *opaque, hwaddr offset, unsigned size)
 230 {
 231     uint32_t value = 0;
 232     IMX25CCMState *s = (IMX25CCMState *)opaque;
 233
 234     if (offset < 0x70) {
 235         value = s->reg[offset >> 2];
 236     } else {
 237         qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
 238                       HWADDR_PRIx "\n", TYPE_IMX25_CCM, __func__, offset);
 239     }
 240
 241     DPRINTF("reg[%s] => 0x%" PRIx32 "\n", imx25_ccm_reg_name(offset >> 2),
 242             value);
 243
 244     return value;
 245 }
 246
 247 static void imx25_ccm_write(void *opaque, hwaddr offset, uint64_t value,
 248                             unsigned size)
 249 {
 250     IMX25CCMState *s = (IMX25CCMState *)opaque;
 251
 252     DPRINTF("reg[%s] <= 0x%" PRIx32 "\n", imx25_ccm_reg_name(offset >> 2),
 253             (uint32_t)value);
 254
 255     if (offset < 0x70) {
 256         /*
 257          * We will do a better implementation later. In particular some bits
 258          * cannot be written to.
 259          */
 260         s->reg[offset >> 2] = value;
 261     } else {
 262         qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
 263                       HWADDR_PRIx "\n", TYPE_IMX25_CCM, __func__, offset);
 264     }
 265 }
 266
 267 static const struct MemoryRegionOps imx25_ccm_ops = {
 268     .read = imx25_ccm_read,
 269     .write = imx25_ccm_write,
 270     .endianness = DEVICE_NATIVE_ENDIAN,
 271     .valid = {
 272         /*
 273          * Our device would not work correctly if the guest was doing
 274          * unaligned access. This might not be a limitation on the real
 275          * device but in practice there is no reason for a guest to access
 276          * this device unaligned.
 277          */
 278         .min_access_size = 4,
 279         .max_access_size = 4,
 280         .unaligned = false,
 281     },
 282 };
 283
 284 static void imx25_ccm_init(Object *obj)
 285 {
 286     DeviceState *dev = DEVICE(obj);
 287     SysBusDevice *sd = SYS_BUS_DEVICE(obj);
 288     IMX25CCMState *s = IMX25_CCM(obj);
 289
 290     memory_region_init_io(&s->iomem, OBJECT(dev), &imx25_ccm_ops, s,
 291                           TYPE_IMX25_CCM, 0x1000);
 292     sysbus_init_mmio(sd, &s->iomem);
 293 }
 294
 295 static void imx25_ccm_class_init(ObjectClass *klass, void *data)
 296 {
 297     DeviceClass *dc = DEVICE_CLASS(klass);
 298     IMXCCMClass *ccm = IMX_CCM_CLASS(klass);
 299
 300     dc->reset = imx25_ccm_reset;
 301     dc->vmsd = &vmstate_imx25_ccm;
 302     dc->desc = "i.MX25 Clock Control Module";
 303
 304     ccm->get_clock_frequency = imx25_ccm_get_clock_frequency;
 305 }
 306
 307 static const TypeInfo imx25_ccm_info = {
 308     .name          = TYPE_IMX25_CCM,
 309     .parent        = TYPE_IMX_CCM,
 310     .instance_size = sizeof(IMX25CCMState),
 311     .instance_init = imx25_ccm_init,
 312     .class_init    = imx25_ccm_class_init,
 313 };
 314
 315 static void imx25_ccm_register_types(void)
 316 {
 317     type_register_static(&imx25_ccm_info);
 318 }
 319
 320 type_init(imx25_ccm_register_types)