hw/dma/soc_dma.c

   1 /*
   2  * On-chip DMA controller framework.
   3  *
   4  * Copyright (C) 2008 Nokia Corporation
   5  * Written by Andrzej Zaborowski <andrew@openedhand.com>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License as
   9  * published by the Free Software Foundation; either version 2 or
  10  * (at your option) version 3 of the License.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20 #include "qemu/osdep.h"
  21 #include "qemu-common.h"
  22 #include "qemu/timer.h"
  23 #include "hw/arm/soc_dma.h"
  24
  25 static void transfer_mem2mem(struct soc_dma_ch_s *ch)
  26 {
  27     memcpy(ch->paddr[0], ch->paddr[1], ch->bytes);
  28     ch->paddr[0] += ch->bytes;
  29     ch->paddr[1] += ch->bytes;
  30 }
  31
  32 static void transfer_mem2fifo(struct soc_dma_ch_s *ch)
  33 {
  34     ch->io_fn[1](ch->io_opaque[1], ch->paddr[0], ch->bytes);
  35     ch->paddr[0] += ch->bytes;
  36 }
  37
  38 static void transfer_fifo2mem(struct soc_dma_ch_s *ch)
  39 {
  40     ch->io_fn[0](ch->io_opaque[0], ch->paddr[1], ch->bytes);
  41     ch->paddr[1] += ch->bytes;
  42 }
  43
  44 /* This is further optimisable but isn't very important because often
  45  * DMA peripherals forbid this kind of transfers and even when they don't,
  46  * oprating systems may not need to use them.  */
  47 static void *fifo_buf;
  48 static int fifo_size;
  49 static void transfer_fifo2fifo(struct soc_dma_ch_s *ch)
  50 {
  51     if (ch->bytes > fifo_size)
  52         fifo_buf = g_realloc(fifo_buf, fifo_size = ch->bytes);
  53
  54     /* Implement as transfer_fifo2linear + transfer_linear2fifo.  */
  55     ch->io_fn[0](ch->io_opaque[0], fifo_buf, ch->bytes);
  56     ch->io_fn[1](ch->io_opaque[1], fifo_buf, ch->bytes);
  57 }
  58
  59 struct dma_s {
  60     struct soc_dma_s soc;
  61     int chnum;
  62     uint64_t ch_enable_mask;
  63     int64_t channel_freq;
  64     int enabled_count;
  65
  66     struct memmap_entry_s {
  67         enum soc_dma_port_type type;
  68         hwaddr addr;
  69         union {
  70            struct {
  71                void *opaque;
  72                soc_dma_io_t fn;
  73                int out;
  74            } fifo;
  75            struct {
  76                void *base;
  77                size_t size;
  78            } mem;
  79         } u;
  80     } *memmap;
  81     int memmap_size;
  82
  83     struct soc_dma_ch_s ch[0];
  84 };
  85
  86 static void soc_dma_ch_schedule(struct soc_dma_ch_s *ch, int delay_bytes)
  87 {
  88     int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
  89     struct dma_s *dma = (struct dma_s *) ch->dma;
  90
  91     timer_mod(ch->timer, now + delay_bytes / dma->channel_freq);
  92 }
  93
  94 static void soc_dma_ch_run(void *opaque)
  95 {
  96     struct soc_dma_ch_s *ch = (struct soc_dma_ch_s *) opaque;
  97
  98     ch->running = 1;
  99     ch->dma->setup_fn(ch);
 100     ch->transfer_fn(ch);
 101     ch->running = 0;
 102
 103     if (ch->enable)
 104         soc_dma_ch_schedule(ch, ch->bytes);
 105     ch->bytes = 0;
 106 }
 107
 108 static inline struct memmap_entry_s *soc_dma_lookup(struct dma_s *dma,
 109                 hwaddr addr)
 110 {
 111     struct memmap_entry_s *lo;
 112     int hi;
 113
 114     lo = dma->memmap;
 115     hi = dma->memmap_size;
 116
 117     while (hi > 1) {
 118         hi /= 2;
 119         if (lo[hi].addr <= addr)
 120             lo += hi;
 121     }
 122
 123     return lo;
 124 }
 125
 126 static inline enum soc_dma_port_type soc_dma_ch_update_type(
 127                 struct soc_dma_ch_s *ch, int port)
 128 {
 129     struct dma_s *dma = (struct dma_s *) ch->dma;
 130     struct memmap_entry_s *entry = soc_dma_lookup(dma, ch->vaddr[port]);
 131
 132     if (entry->type == soc_dma_port_fifo) {
 133         while (entry < dma->memmap + dma->memmap_size &&
 134                         entry->u.fifo.out != port)
 135             entry ++;
 136         if (entry->addr != ch->vaddr[port] || entry->u.fifo.out != port)
 137             return soc_dma_port_other;
 138
 139         if (ch->type[port] != soc_dma_access_const)
 140             return soc_dma_port_other;
 141
 142         ch->io_fn[port] = entry->u.fifo.fn;
 143         ch->io_opaque[port] = entry->u.fifo.opaque;
 144         return soc_dma_port_fifo;
 145     } else if (entry->type == soc_dma_port_mem) {
 146         if (entry->addr > ch->vaddr[port] ||
 147                         entry->addr + entry->u.mem.size <= ch->vaddr[port])
 148             return soc_dma_port_other;
 149
 150         /* TODO: support constant memory address for source port as used for
 151          * drawing solid rectangles by PalmOS(R).  */
 152         if (ch->type[port] != soc_dma_access_const)
 153             return soc_dma_port_other;
 154
 155         ch->paddr[port] = (uint8_t *) entry->u.mem.base +
 156                 (ch->vaddr[port] - entry->addr);
 157         /* TODO: save bytes left to the end of the mapping somewhere so we
 158          * can check we're not reading beyond it.  */
 159         return soc_dma_port_mem;
 160     } else
 161         return soc_dma_port_other;
 162 }
 163
 164 void soc_dma_ch_update(struct soc_dma_ch_s *ch)
 165 {
 166     enum soc_dma_port_type src, dst;
 167
 168     src = soc_dma_ch_update_type(ch, 0);
 169     if (src == soc_dma_port_other) {
 170         ch->update = 0;
 171         ch->transfer_fn = ch->dma->transfer_fn;
 172         return;
 173     }
 174     dst = soc_dma_ch_update_type(ch, 1);
 175
 176     /* TODO: use src and dst as array indices.  */
 177     if (src == soc_dma_port_mem && dst == soc_dma_port_mem)
 178         ch->transfer_fn = transfer_mem2mem;
 179     else if (src == soc_dma_port_mem && dst == soc_dma_port_fifo)
 180         ch->transfer_fn = transfer_mem2fifo;
 181     else if (src == soc_dma_port_fifo && dst == soc_dma_port_mem)
 182         ch->transfer_fn = transfer_fifo2mem;
 183     else if (src == soc_dma_port_fifo && dst == soc_dma_port_fifo)
 184         ch->transfer_fn = transfer_fifo2fifo;
 185     else
 186         ch->transfer_fn = ch->dma->transfer_fn;
 187
 188     ch->update = (dst != soc_dma_port_other);
 189 }
 190
 191 static void soc_dma_ch_freq_update(struct dma_s *s)
 192 {
 193     if (s->enabled_count)
 194         /* We completely ignore channel priorities and stuff */
 195         s->channel_freq = s->soc.freq / s->enabled_count;
 196     else {
 197         /* TODO: Signal that we want to disable the functional clock and let
 198          * the platform code decide what to do with it, i.e. check that
 199          * auto-idle is enabled in the clock controller and if we are stopping
 200          * the clock, do the same with any parent clocks that had only one
 201          * user keeping them on and auto-idle enabled.  */
 202     }
 203 }
 204
 205 void soc_dma_set_request(struct soc_dma_ch_s *ch, int level)
 206 {
 207     struct dma_s *dma = (struct dma_s *) ch->dma;
 208
 209     dma->enabled_count += level - ch->enable;
 210
 211     if (level)
 212         dma->ch_enable_mask |= 1 << ch->num;
 213     else
 214         dma->ch_enable_mask &= ~(1 << ch->num);
 215
 216     if (level != ch->enable) {
 217         soc_dma_ch_freq_update(dma);
 218         ch->enable = level;
 219
 220         if (!ch->enable)
 221             timer_del(ch->timer);
 222         else if (!ch->running)
 223             soc_dma_ch_run(ch);
 224         else
 225             soc_dma_ch_schedule(ch, 1);
 226     }
 227 }
 228
 229 void soc_dma_reset(struct soc_dma_s *soc)
 230 {
 231     struct dma_s *s = (struct dma_s *) soc;
 232
 233     s->soc.drqbmp = 0;
 234     s->ch_enable_mask = 0;
 235     s->enabled_count = 0;
 236     soc_dma_ch_freq_update(s);
 237 }
 238
 239 /* TODO: take a functional-clock argument */
 240 struct soc_dma_s *soc_dma_init(int n)
 241 {
 242     int i;
 243     struct dma_s *s = g_malloc0(sizeof(*s) + n * sizeof(*s->ch));
 244
 245     s->chnum = n;
 246     s->soc.ch = s->ch;
 247     for (i = 0; i < n; i ++) {
 248         s->ch[i].dma = &s->soc;
 249         s->ch[i].num = i;
 250         s->ch[i].timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, soc_dma_ch_run, &s->ch[i]);
 251     }
 252
 253     soc_dma_reset(&s->soc);
 254     fifo_size = 0;
 255
 256     return &s->soc;
 257 }
 258
 259 void soc_dma_port_add_fifo(struct soc_dma_s *soc, hwaddr virt_base,
 260                 soc_dma_io_t fn, void *opaque, int out)
 261 {
 262     struct memmap_entry_s *entry;
 263     struct dma_s *dma = (struct dma_s *) soc;
 264
 265     dma->memmap = g_realloc(dma->memmap, sizeof(*entry) *
 266                     (dma->memmap_size + 1));
 267     entry = soc_dma_lookup(dma, virt_base);
 268
 269     if (dma->memmap_size) {
 270         if (entry->type == soc_dma_port_mem) {
 271             if (entry->addr <= virt_base &&
 272                             entry->addr + entry->u.mem.size > virt_base) {
 273                 fprintf(stderr, "%s: FIFO at %"PRIx64
 274                                 " collides with RAM region at %"PRIx64
 275                                 "-%"PRIx64 "\n", __func__,
 276                                 virt_base, entry->addr,
 277                                 (entry->addr + entry->u.mem.size));
 278                 exit(-1);
 279             }
 280
 281             if (entry->addr <= virt_base)
 282                 entry ++;
 283         } else
 284             while (entry < dma->memmap + dma->memmap_size &&
 285                             entry->addr <= virt_base) {
 286                 if (entry->addr == virt_base && entry->u.fifo.out == out) {
 287                     fprintf(stderr, "%s: FIFO at %"PRIx64
 288                                     " collides FIFO at %"PRIx64 "\n",
 289                                     __func__, virt_base, entry->addr);
 290                     exit(-1);
 291                 }
 292
 293                 entry ++;
 294             }
 295
 296         memmove(entry + 1, entry,
 297                         (uint8_t *) (dma->memmap + dma->memmap_size ++) -
 298                         (uint8_t *) entry);
 299     } else
 300         dma->memmap_size ++;
 301
 302     entry->addr          = virt_base;
 303     entry->type          = soc_dma_port_fifo;
 304     entry->u.fifo.fn     = fn;
 305     entry->u.fifo.opaque = opaque;
 306     entry->u.fifo.out    = out;
 307 }
 308
 309 void soc_dma_port_add_mem(struct soc_dma_s *soc, uint8_t *phys_base,
 310                 hwaddr virt_base, size_t size)
 311 {
 312     struct memmap_entry_s *entry;
 313     struct dma_s *dma = (struct dma_s *) soc;
 314
 315     dma->memmap = g_realloc(dma->memmap, sizeof(*entry) *
 316                     (dma->memmap_size + 1));
 317     entry = soc_dma_lookup(dma, virt_base);
 318
 319     if (dma->memmap_size) {
 320         if (entry->type == soc_dma_port_mem) {
 321             if ((entry->addr >= virt_base && entry->addr < virt_base + size) ||
 322                             (entry->addr <= virt_base &&
 323                              entry->addr + entry->u.mem.size > virt_base)) {
 324                 fprintf(stderr, "%s: RAM at %"PRIx64 "-%"PRIx64
 325                                 " collides with RAM region at %"PRIx64
 326                                 "-%"PRIx64 "\n", __func__,
 327                                 virt_base, virt_base + size,
 328                                 entry->addr, entry->addr + entry->u.mem.size);
 329                 exit(-1);
 330             }
 331
 332             if (entry->addr <= virt_base)
 333                 entry ++;
 334         } else {
 335             if (entry->addr >= virt_base &&
 336                             entry->addr < virt_base + size) {
 337                 fprintf(stderr, "%s: RAM at %"PRIx64 "-%"PRIx64
 338                                 " collides with FIFO at %"PRIx64
 339                                 "\n", __func__,
 340                                 virt_base, virt_base + size,
 341                                 entry->addr);
 342                 exit(-1);
 343             }
 344
 345             while (entry < dma->memmap + dma->memmap_size &&
 346                             entry->addr <= virt_base)
 347                 entry ++;
 348         }
 349
 350         memmove(entry + 1, entry,
 351                         (uint8_t *) (dma->memmap + dma->memmap_size ++) -
 352                         (uint8_t *) entry);
 353     } else
 354         dma->memmap_size ++;
 355
 356     entry->addr          = virt_base;
 357     entry->type          = soc_dma_port_mem;
 358     entry->u.mem.base    = phys_base;
 359     entry->u.mem.size    = size;
 360 }
 361
 362 /* TODO: port removal for ports like PCMCIA memory */