hw/pl080.c

   1 /*
   2  * Arm PrimeCell PL080/PL081 DMA controller
   3  *
   4  * Copyright (c) 2006 CodeSourcery.
   5  * Written by Paul Brook
   6  *
   7  * This code is licenced under the GPL.
   8  */
   9
  10 #include "hw.h"
  11 #include "primecell.h"
  12
  13 #define PL080_MAX_CHANNELS 8
  14 #define PL080_CONF_E    0x1
  15 #define PL080_CONF_M1   0x2
  16 #define PL080_CONF_M2   0x4
  17
  18 #define PL080_CCONF_H   0x40000
  19 #define PL080_CCONF_A   0x20000
  20 #define PL080_CCONF_L   0x10000
  21 #define PL080_CCONF_ITC 0x08000
  22 #define PL080_CCONF_IE  0x04000
  23 #define PL080_CCONF_E   0x00001
  24
  25 #define PL080_CCTRL_I   0x80000000
  26 #define PL080_CCTRL_DI  0x08000000
  27 #define PL080_CCTRL_SI  0x04000000
  28 #define PL080_CCTRL_D   0x02000000
  29 #define PL080_CCTRL_S   0x01000000
  30
  31 typedef struct {
  32     uint32_t src;
  33     uint32_t dest;
  34     uint32_t lli;
  35     uint32_t ctrl;
  36     uint32_t conf;
  37 } pl080_channel;
  38
  39 typedef struct {
  40     uint8_t tc_int;
  41     uint8_t tc_mask;
  42     uint8_t err_int;
  43     uint8_t err_mask;
  44     uint32_t conf;
  45     uint32_t sync;
  46     uint32_t req_single;
  47     uint32_t req_burst;
  48     pl080_channel chan[PL080_MAX_CHANNELS];
  49     int nchannels;
  50     /* Flag to avoid recursive DMA invocations.  */
  51     int running;
  52     qemu_irq irq;
  53 } pl080_state;
  54
  55 static const unsigned char pl080_id[] =
  56 { 0x80, 0x10, 0x04, 0x0a, 0x0d, 0xf0, 0x05, 0xb1 };
  57
  58 static const unsigned char pl081_id[] =
  59 { 0x81, 0x10, 0x04, 0x0a, 0x0d, 0xf0, 0x05, 0xb1 };
  60
  61 static void pl080_update(pl080_state *s)
  62 {
  63     if ((s->tc_int & s->tc_mask)
  64             || (s->err_int & s->err_mask))
  65         qemu_irq_raise(s->irq);
  66     else
  67         qemu_irq_lower(s->irq);
  68 }
  69
  70 static void pl080_run(pl080_state *s)
  71 {
  72     int c;
  73     int flow;
  74     pl080_channel *ch;
  75     int swidth;
  76     int dwidth;
  77     int xsize;
  78     int n;
  79     int src_id;
  80     int dest_id;
  81     int size;
  82     uint8_t buff[4];
  83     uint32_t req;
  84
  85     s->tc_mask = 0;
  86     for (c = 0; c < s->nchannels; c++) {
  87         if (s->chan[c].conf & PL080_CCONF_ITC)
  88             s->tc_mask |= 1 << c;
  89         if (s->chan[c].conf & PL080_CCONF_IE)
  90             s->err_mask |= 1 << c;
  91     }
  92
  93     if ((s->conf & PL080_CONF_E) == 0)
  94         return;
  95
  96 cpu_abort(cpu_single_env, "DMA active\n");
  97     /* If we are already in the middle of a DMA operation then indicate that
  98        there may be new DMA requests and return immediately.  */
  99     if (s->running) {
 100         s->running++;
 101         return;
 102     }
 103     s->running = 1;
 104     while (s->running) {
 105         for (c = 0; c < s->nchannels; c++) {
 106             ch = &s->chan[c];
 107 again:
 108             /* Test if thiws channel has any pending DMA requests.  */
 109             if ((ch->conf & (PL080_CCONF_H | PL080_CCONF_E))
 110                     != PL080_CCONF_E)
 111                 continue;
 112             flow = (ch->conf >> 11) & 7;
 113             if (flow >= 4) {
 114                 cpu_abort(cpu_single_env,
 115                     "pl080_run: Peripheral flow control not implemented\n");
 116             }
 117             src_id = (ch->conf >> 1) & 0x1f;
 118             dest_id = (ch->conf >> 6) & 0x1f;
 119             size = ch->ctrl & 0xfff;
 120             req = s->req_single | s->req_burst;
 121             switch (flow) {
 122             case 0:
 123                 break;
 124             case 1:
 125                 if ((req & (1u << dest_id)) == 0)
 126                     size = 0;
 127                 break;
 128             case 2:
 129                 if ((req & (1u << src_id)) == 0)
 130                     size = 0;
 131                 break;
 132             case 3:
 133                 if ((req & (1u << src_id)) == 0
 134                         || (req & (1u << dest_id)) == 0)
 135                     size = 0;
 136                 break;
 137             }
 138             if (!size)
 139                 continue;
 140
 141             /* Transfer one element.  */
 142             /* ??? Should transfer multiple elements for a burst request.  */
 143             /* ??? Unclear what the proper behavior is when source and
 144                destination widths are different.  */
 145             swidth = 1 << ((ch->ctrl >> 18) & 7);
 146             dwidth = 1 << ((ch->ctrl >> 21) & 7);
 147             for (n = 0; n < dwidth; n+= swidth) {
 148                 cpu_physical_memory_read(ch->src, buff + n, swidth);
 149                 if (ch->ctrl & PL080_CCTRL_SI)
 150                     ch->src += swidth;
 151             }
 152             xsize = (dwidth < swidth) ? swidth : dwidth;
 153             /* ??? This may pad the value incorrectly for dwidth < 32.  */
 154             for (n = 0; n < xsize; n += dwidth) {
 155                 cpu_physical_memory_write(ch->dest + n, buff + n, dwidth);
 156                 if (ch->ctrl & PL080_CCTRL_DI)
 157                     ch->dest += swidth;
 158             }
 159
 160             size--;
 161             ch->ctrl = (ch->ctrl & 0xfffff000) | size;
 162             if (size == 0) {
 163                 /* Transfer complete.  */
 164                 if (ch->lli) {
 165                     ch->src = ldl_phys(ch->lli);
 166                     ch->dest = ldl_phys(ch->lli + 4);
 167                     ch->ctrl = ldl_phys(ch->lli + 12);
 168                     ch->lli = ldl_phys(ch->lli + 8);
 169                 } else {
 170                     ch->conf &= ~PL080_CCONF_E;
 171                 }
 172                 if (ch->ctrl & PL080_CCTRL_I) {
 173                     s->tc_int |= 1 << c;
 174                 }
 175             }
 176             goto again;
 177         }
 178         if (--s->running)
 179             s->running = 1;
 180     }
 181 }
 182
 183 static uint32_t pl080_read(void *opaque, target_phys_addr_t offset)
 184 {
 185     pl080_state *s = (pl080_state *)opaque;
 186     uint32_t i;
 187     uint32_t mask;
 188
 189     if (offset >= 0xfe0 && offset < 0x1000) {
 190         if (s->nchannels == 8) {
 191             return pl080_id[(offset - 0xfe0) >> 2];
 192         } else {
 193             return pl081_id[(offset - 0xfe0) >> 2];
 194         }
 195     }
 196     if (offset >= 0x100 && offset < 0x200) {
 197         i = (offset & 0xe0) >> 5;
 198         if (i >= s->nchannels)
 199             goto bad_offset;
 200         switch (offset >> 2) {
 201         case 0: /* SrcAddr */
 202             return s->chan[i].src;
 203         case 1: /* DestAddr */
 204             return s->chan[i].dest;
 205         case 2: /* LLI */
 206             return s->chan[i].lli;
 207         case 3: /* Control */
 208             return s->chan[i].ctrl;
 209         case 4: /* Configuration */
 210             return s->chan[i].conf;
 211         default:
 212             goto bad_offset;
 213         }
 214     }
 215     switch (offset >> 2) {
 216     case 0: /* IntStatus */
 217         return (s->tc_int & s->tc_mask) | (s->err_int & s->err_mask);
 218     case 1: /* IntTCStatus */
 219         return (s->tc_int & s->tc_mask);
 220     case 3: /* IntErrorStatus */
 221         return (s->err_int & s->err_mask);
 222     case 5: /* RawIntTCStatus */
 223         return s->tc_int;
 224     case 6: /* RawIntErrorStatus */
 225         return s->err_int;
 226     case 7: /* EnbldChns */
 227         mask = 0;
 228         for (i = 0; i < s->nchannels; i++) {
 229             if (s->chan[i].conf & PL080_CCONF_E)
 230                 mask |= 1 << i;
 231         }
 232         return mask;
 233     case 8: /* SoftBReq */
 234     case 9: /* SoftSReq */
 235     case 10: /* SoftLBReq */
 236     case 11: /* SoftLSReq */
 237         /* ??? Implement these. */
 238         return 0;
 239     case 12: /* Configuration */
 240         return s->conf;
 241     case 13: /* Sync */
 242         return s->sync;
 243     default:
 244     bad_offset:
 245         cpu_abort(cpu_single_env, "pl080_read: Bad offset %x\n", (int)offset);
 246         return 0;
 247     }
 248 }
 249
 250 static void pl080_write(void *opaque, target_phys_addr_t offset,
 251                           uint32_t value)
 252 {
 253     pl080_state *s = (pl080_state *)opaque;
 254     int i;
 255
 256     if (offset >= 0x100 && offset < 0x200) {
 257         i = (offset & 0xe0) >> 5;
 258         if (i >= s->nchannels)
 259             goto bad_offset;
 260         switch (offset >> 2) {
 261         case 0: /* SrcAddr */
 262             s->chan[i].src = value;
 263             break;
 264         case 1: /* DestAddr */
 265             s->chan[i].dest = value;
 266             break;
 267         case 2: /* LLI */
 268             s->chan[i].lli = value;
 269             break;
 270         case 3: /* Control */
 271             s->chan[i].ctrl = value;
 272             break;
 273         case 4: /* Configuration */
 274             s->chan[i].conf = value;
 275             pl080_run(s);
 276             break;
 277         }
 278     }
 279     switch (offset >> 2) {
 280     case 2: /* IntTCClear */
 281         s->tc_int &= ~value;
 282         break;
 283     case 4: /* IntErrorClear */
 284         s->err_int &= ~value;
 285         break;
 286     case 8: /* SoftBReq */
 287     case 9: /* SoftSReq */
 288     case 10: /* SoftLBReq */
 289     case 11: /* SoftLSReq */
 290         /* ??? Implement these.  */
 291         cpu_abort(cpu_single_env, "pl080_write: Soft DMA not implemented\n");
 292         break;
 293     case 12: /* Configuration */
 294         s->conf = value;
 295         if (s->conf & (PL080_CONF_M1 | PL080_CONF_M1)) {
 296             cpu_abort(cpu_single_env,
 297                       "pl080_write: Big-endian DMA not implemented\n");
 298         }
 299         pl080_run(s);
 300         break;
 301     case 13: /* Sync */
 302         s->sync = value;
 303         break;
 304     default:
 305     bad_offset:
 306         cpu_abort(cpu_single_env, "pl080_write: Bad offset %x\n", (int)offset);
 307     }
 308     pl080_update(s);
 309 }
 310
 311 static CPUReadMemoryFunc *pl080_readfn[] = {
 312    pl080_read,
 313    pl080_read,
 314    pl080_read
 315 };
 316
 317 static CPUWriteMemoryFunc *pl080_writefn[] = {
 318    pl080_write,
 319    pl080_write,
 320    pl080_write
 321 };
 322
 323 /* The PL080 and PL081 are the same except for the number of channels
 324    they implement (8 and 2 respectively).  */
 325 void *pl080_init(uint32_t base, qemu_irq irq, int nchannels)
 326 {
 327     int iomemtype;
 328     pl080_state *s;
 329
 330     s = (pl080_state *)qemu_mallocz(sizeof(pl080_state));
 331     iomemtype = cpu_register_io_memory(0, pl080_readfn,
 332                                        pl080_writefn, s);
 333     cpu_register_physical_memory(base, 0x00001000, iomemtype);
 334     s->irq = irq;
 335     s->nchannels = nchannels;
 336     /* ??? Save/restore.  */
 337     return s;
 338 }