drivers/gpu/drm/nouveau/nouveau_dma.c

   1 /*
   2  * Copyright (C) 2007 Ben Skeggs.
   3  * All Rights Reserved.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining
   6  * a copy of this software and associated documentation files (the
   7  * "Software"), to deal in the Software without restriction, including
   8  * without limitation the rights to use, copy, modify, merge, publish,
   9  * distribute, sublicense, and/or sell copies of the Software, and to
  10  * permit persons to whom the Software is furnished to do so, subject to
  11  * the following conditions:
  12  *
  13  * The above copyright notice and this permission notice (including the
  14  * next paragraph) shall be included in all copies or substantial
  15  * portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  18  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  20  * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
  21  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  22  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  23  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  24  *
  25  */
  26
  27 #include "drmP.h"
  28 #include "drm.h"
  29 #include "nouveau_drv.h"
  30 #include "nouveau_dma.h"
  31 #include "nouveau_ramht.h"
  32
  33 void
  34 nouveau_dma_pre_init(struct nouveau_channel *chan)
  35 {
  36         struct drm_nouveau_private *dev_priv = chan->dev->dev_private;
  37         struct nouveau_bo *pushbuf = chan->pushbuf_bo;
  38
  39         if (dev_priv->card_type >= NV_50) {
  40                 const int ib_size = pushbuf->bo.mem.size / 2;
  41
  42                 chan->dma.ib_base = (pushbuf->bo.mem.size - ib_size) >> 2;
  43                 chan->dma.ib_max = (ib_size / 8) - 1;
  44                 chan->dma.ib_put = 0;
  45                 chan->dma.ib_free = chan->dma.ib_max - chan->dma.ib_put;
  46
  47                 chan->dma.max = (pushbuf->bo.mem.size - ib_size) >> 2;
  48         } else {
  49                 chan->dma.max  = (pushbuf->bo.mem.size >> 2) - 2;
  50         }
  51
  52         chan->dma.put  = 0;
  53         chan->dma.cur  = chan->dma.put;
  54         chan->dma.free = chan->dma.max - chan->dma.cur;
  55 }
  56
  57 int
  58 nouveau_dma_init(struct nouveau_channel *chan)
  59 {
  60         struct drm_device *dev = chan->dev;
  61         struct drm_nouveau_private *dev_priv = dev->dev_private;
  62         int ret, i;
  63
  64         if (dev_priv->card_type >= NV_C0) {
  65                 ret = nouveau_gpuobj_gr_new(chan, 0x9039, 0x9039);
  66                 if (ret)
  67                         return ret;
  68
  69                 ret = RING_SPACE(chan, 2);
  70                 if (ret)
  71                         return ret;
  72
  73                 BEGIN_NVC0(chan, 2, NvSubM2MF, 0x0000, 1);
  74                 OUT_RING  (chan, 0x00009039);
  75                 FIRE_RING (chan);
  76                 return 0;
  77         }
  78
  79         /* Create NV_MEMORY_TO_MEMORY_FORMAT for buffer moves */
  80         ret = nouveau_gpuobj_gr_new(chan, NvM2MF, dev_priv->card_type < NV_50 ?
  81                                     0x0039 : 0x5039);
  82         if (ret)
  83                 return ret;
  84
  85         /* NV_MEMORY_TO_MEMORY_FORMAT requires a notifier object */
  86         ret = nouveau_notifier_alloc(chan, NvNotify0, 32, 0xfe0, 0x1000,
  87                                      &chan->m2mf_ntfy);
  88         if (ret)
  89                 return ret;
  90
  91         /* Insert NOPS for NOUVEAU_DMA_SKIPS */
  92         ret = RING_SPACE(chan, NOUVEAU_DMA_SKIPS);
  93         if (ret)
  94                 return ret;
  95
  96         for (i = 0; i < NOUVEAU_DMA_SKIPS; i++)
  97                 OUT_RING(chan, 0);
  98
  99         /* Initialise NV_MEMORY_TO_MEMORY_FORMAT */
 100         ret = RING_SPACE(chan, 6);
 101         if (ret)
 102                 return ret;
 103         BEGIN_RING(chan, NvSubM2MF, NV_MEMORY_TO_MEMORY_FORMAT_NAME, 1);
 104         OUT_RING  (chan, NvM2MF);
 105         BEGIN_RING(chan, NvSubM2MF, NV_MEMORY_TO_MEMORY_FORMAT_DMA_NOTIFY, 3);
 106         OUT_RING  (chan, NvNotify0);
 107         OUT_RING  (chan, chan->vram_handle);
 108         OUT_RING  (chan, chan->gart_handle);
 109
 110         /* Sit back and pray the channel works.. */
 111         FIRE_RING(chan);
 112
 113         return 0;
 114 }
 115
 116 void
 117 OUT_RINGp(struct nouveau_channel *chan, const void *data, unsigned nr_dwords)
 118 {
 119         bool is_iomem;
 120         u32 *mem = ttm_kmap_obj_virtual(&chan->pushbuf_bo->kmap, &is_iomem);
 121         mem = &mem[chan->dma.cur];
 122         if (is_iomem)
 123                 memcpy_toio((void __force __iomem *)mem, data, nr_dwords * 4);
 124         else
 125                 memcpy(mem, data, nr_dwords * 4);
 126         chan->dma.cur += nr_dwords;
 127 }
 128
 129 /* Fetch and adjust GPU GET pointer
 130  *
 131  * Returns:
 132  *  value >= 0, the adjusted GET pointer
 133  *  -EINVAL if GET pointer currently outside main push buffer
 134  *  -EBUSY if timeout exceeded
 135  */
 136 static inline int
 137 READ_GET(struct nouveau_channel *chan, uint32_t *prev_get, uint32_t *timeout)
 138 {
 139         uint32_t val;
 140
 141         val = nvchan_rd32(chan, chan->user_get);
 142
 143         /* reset counter as long as GET is still advancing, this is
 144          * to avoid misdetecting a GPU lockup if the GPU happens to
 145          * just be processing an operation that takes a long time
 146          */
 147         if (val != *prev_get) {
 148                 *prev_get = val;
 149                 *timeout = 0;
 150         }
 151
 152         if ((++*timeout & 0xff) == 0) {
 153                 DRM_UDELAY(1);
 154                 if (*timeout > 100000)
 155                         return -EBUSY;
 156         }
 157
 158         if (val < chan->pushbuf_base ||
 159             val > chan->pushbuf_base + (chan->dma.max << 2))
 160                 return -EINVAL;
 161
 162         return (val - chan->pushbuf_base) >> 2;
 163 }
 164
 165 void
 166 nv50_dma_push(struct nouveau_channel *chan, struct nouveau_bo *bo,
 167               int delta, int length)
 168 {
 169         struct nouveau_bo *pb = chan->pushbuf_bo;
 170         struct nouveau_vma *vma;
 171         int ip = (chan->dma.ib_put * 2) + chan->dma.ib_base;
 172         u64 offset;
 173
 174         vma = nouveau_bo_vma_find(bo, chan->vm);
 175         BUG_ON(!vma);
 176         offset = vma->offset + delta;
 177
 178         BUG_ON(chan->dma.ib_free < 1);
 179         nouveau_bo_wr32(pb, ip++, lower_32_bits(offset));
 180         nouveau_bo_wr32(pb, ip++, upper_32_bits(offset) | length << 8);
 181
 182         chan->dma.ib_put = (chan->dma.ib_put + 1) & chan->dma.ib_max;
 183
 184         DRM_MEMORYBARRIER();
 185         /* Flush writes. */
 186         nouveau_bo_rd32(pb, 0);
 187
 188         nvchan_wr32(chan, 0x8c, chan->dma.ib_put);
 189         chan->dma.ib_free--;
 190 }
 191
 192 static int
 193 nv50_dma_push_wait(struct nouveau_channel *chan, int count)
 194 {
 195         uint32_t cnt = 0, prev_get = 0;
 196
 197         while (chan->dma.ib_free < count) {
 198                 uint32_t get = nvchan_rd32(chan, 0x88);
 199                 if (get != prev_get) {
 200                         prev_get = get;
 201                         cnt = 0;
 202                 }
 203
 204                 if ((++cnt & 0xff) == 0) {
 205                         DRM_UDELAY(1);
 206                         if (cnt > 100000)
 207                                 return -EBUSY;
 208                 }
 209
 210                 chan->dma.ib_free = get - chan->dma.ib_put;
 211                 if (chan->dma.ib_free <= 0)
 212                         chan->dma.ib_free += chan->dma.ib_max;
 213         }
 214
 215         return 0;
 216 }
 217
 218 static int
 219 nv50_dma_wait(struct nouveau_channel *chan, int slots, int count)
 220 {
 221         uint32_t cnt = 0, prev_get = 0;
 222         int ret;
 223
 224         ret = nv50_dma_push_wait(chan, slots + 1);
 225         if (unlikely(ret))
 226                 return ret;
 227
 228         while (chan->dma.free < count) {
 229                 int get = READ_GET(chan, &prev_get, &cnt);
 230                 if (unlikely(get < 0)) {
 231                         if (get == -EINVAL)
 232                                 continue;
 233
 234                         return get;
 235                 }
 236
 237                 if (get <= chan->dma.cur) {
 238                         chan->dma.free = chan->dma.max - chan->dma.cur;
 239                         if (chan->dma.free >= count)
 240                                 break;
 241
 242                         FIRE_RING(chan);
 243                         do {
 244                                 get = READ_GET(chan, &prev_get, &cnt);
 245                                 if (unlikely(get < 0)) {
 246                                         if (get == -EINVAL)
 247                                                 continue;
 248                                         return get;
 249                                 }
 250                         } while (get == 0);
 251                         chan->dma.cur = 0;
 252                         chan->dma.put = 0;
 253                 }
 254
 255                 chan->dma.free = get - chan->dma.cur - 1;
 256         }
 257
 258         return 0;
 259 }
 260
 261 int
 262 nouveau_dma_wait(struct nouveau_channel *chan, int slots, int size)
 263 {
 264         uint32_t prev_get = 0, cnt = 0;
 265         int get;
 266
 267         if (chan->dma.ib_max)
 268                 return nv50_dma_wait(chan, slots, size);
 269
 270         while (chan->dma.free < size) {
 271                 get = READ_GET(chan, &prev_get, &cnt);
 272                 if (unlikely(get == -EBUSY))
 273                         return -EBUSY;
 274
 275                 /* loop until we have a usable GET pointer.  the value
 276                  * we read from the GPU may be outside the main ring if
 277                  * PFIFO is processing a buffer called from the main ring,
 278                  * discard these values until something sensible is seen.
 279                  *
 280                  * the other case we discard GET is while the GPU is fetching
 281                  * from the SKIPS area, so the code below doesn't have to deal
 282                  * with some fun corner cases.
 283                  */
 284                 if (unlikely(get == -EINVAL) || get < NOUVEAU_DMA_SKIPS)
 285                         continue;
 286
 287                 if (get <= chan->dma.cur) {
 288                         /* engine is fetching behind us, or is completely
 289                          * idle (GET == PUT) so we have free space up until
 290                          * the end of the push buffer
 291                          *
 292                          * we can only hit that path once per call due to
 293                          * looping back to the beginning of the push buffer,
 294                          * we'll hit the fetching-ahead-of-us path from that
 295                          * point on.
 296                          *
 297                          * the *one* exception to that rule is if we read
 298                          * GET==PUT, in which case the below conditional will
 299                          * always succeed and break us out of the wait loop.
 300                          */
 301                         chan->dma.free = chan->dma.max - chan->dma.cur;
 302                         if (chan->dma.free >= size)
 303                                 break;
 304
 305                         /* not enough space left at the end of the push buffer,
 306                          * instruct the GPU to jump back to the start right
 307                          * after processing the currently pending commands.
 308                          */
 309                         OUT_RING(chan, chan->pushbuf_base | 0x20000000);
 310
 311                         /* wait for GET to depart from the skips area.
 312                          * prevents writing GET==PUT and causing a race
 313                          * condition that causes us to think the GPU is
 314                          * idle when it's not.
 315                          */
 316                         do {
 317                                 get = READ_GET(chan, &prev_get, &cnt);
 318                                 if (unlikely(get == -EBUSY))
 319                                         return -EBUSY;
 320                                 if (unlikely(get == -EINVAL))
 321                                         continue;
 322                         } while (get <= NOUVEAU_DMA_SKIPS);
 323                         WRITE_PUT(NOUVEAU_DMA_SKIPS);
 324
 325                         /* we're now submitting commands at the start of
 326                          * the push buffer.
 327                          */
 328                         chan->dma.cur  =
 329                         chan->dma.put  = NOUVEAU_DMA_SKIPS;
 330                 }
 331
 332                 /* engine fetching ahead of us, we have space up until the
 333                  * current GET pointer.  the "- 1" is to ensure there's
 334                  * space left to emit a jump back to the beginning of the
 335                  * push buffer if we require it.  we can never get GET == PUT
 336                  * here, so this is safe.
 337                  */
 338                 chan->dma.free = get - chan->dma.cur - 1;
 339         }
 340
 341         return 0;
 342 }
 343