cell: implement fencing for texture buffers

If we delete a texture, we need to keep the underlying tiled data buffer
around until any rendering that references it has completed.
Keep a list of buffers referenced by a rendering batch.  Unref/free them when
the associated batch's fence is executed/signalled.

src/gallium/drivers/cell/common.h

@@ -102,6 +102,8 @@
 #define CELL_CMD_STATE_RASTERIZER    22
 #define CELL_CMD_VS_EXECUTE          23
 #define CELL_CMD_FLUSH_BUFFER_RANGE  24
+#define CELL_CMD_FENCE               25
+
 
 /** Command/batch buffers */
 #define CELL_NUM_BUFFERS 4
@@ -123,6 +125,29 @@
 #define SPU_MAX_FRAGMENT_OPS_INSTS 64
 
 
+
+#define CELL_FENCE_IDLE      0
+#define CELL_FENCE_EMITTED   1
+#define CELL_FENCE_SIGNALLED 2
+
+struct cell_fence
+{
+   /** There's a 16-byte status qword per SPU */
+   volatile uint status[CELL_MAX_SPUS][4];
+};
+
+
+/**
+ * Fence command sent to SPUs.  In response, the SPUs will write
+ * CELL_FENCE_STATUS_SIGNALLED back to the fence status word in main memory.
+ */
+struct cell_command_fence
+{
+   uint64_t opcode;      /**< CELL_CMD_FENCE */
+   struct cell_fence *fence;
+};
+
+
 /**
  * Command to specify per-fragment operations state and generated code.
  * Note that the dsa, blend, blend_color fields are really only needed

src/gallium/drivers/cell/ppu/Makefile

@@ -24,6 +24,7 @@ SOURCES = \
 	cell_clear.c \
 	cell_context.c \
 	cell_draw_arrays.c \
+	cell_fence.c \
 	cell_flush.c \
 	cell_gen_fragment.c \
 	cell_gen_fp.c \

src/gallium/drivers/cell/ppu/cell_batch.c

@@ -28,6 +28,7 @@
 
 #include "cell_context.h"
 #include "cell_batch.h"
+#include "cell_fence.h"
 #include "cell_spu.h"
 
 
@@ -63,6 +64,10 @@ cell_get_empty_buffer(struct cell_context *cell)
                printf("PPU: ALLOC BUFFER %u, %u tries\n", buf, tries);
                */
                prev_buffer = buf;
+
+               /* release tex buffer associated w/ prev use of this batch buf */
+               cell_free_fenced_buffers(cell, &cell->fenced_buffers[buf]);
+
                return buf;
             }
          }
@@ -84,6 +89,26 @@ cell_get_empty_buffer(struct cell_context *cell)
 }
 
 
+/**
+ * Append a fence command to the current batch buffer.
+ * Note that we're sure there's always room for this because of the
+ * adjusted size check in cell_batch_free_space().
+ */
+static void
+emit_fence(struct cell_context *cell)
+{
+   const uint batch = cell->cur_batch;
+   const uint size = cell->buffer_size[batch];
+   struct cell_command_fence *fence_cmd;
+
+   ASSERT(size + sizeof(struct cell_command_fence) <= CELL_BUFFER_SIZE);
+
+   fence_cmd = (struct cell_command_fence *) (cell->buffer[batch] + size);
+   fence_cmd->opcode = CELL_CMD_FENCE;
+   fence_cmd->fence = &cell->fenced_buffers[batch].fence;
+}
+
+
 /**
  * Flush the current batch buffer to the SPUs.
  * An empty buffer will be found and set as the new current batch buffer
@@ -102,6 +127,12 @@ cell_batch_flush(struct cell_context *cell)
    if (size == 0)
       return;
 
+   /* Before we use this batch buffer, make sure any fenced texture buffers
+    * are released.
+    */
+   if (cell->fenced_buffers[batch].head)
+      emit_fence(cell);
+
    flushing = TRUE;
 
    assert(batch < CELL_NUM_BUFFERS);
@@ -142,6 +173,7 @@ uint
 cell_batch_free_space(const struct cell_context *cell)
 {
    uint free = CELL_BUFFER_SIZE - cell->buffer_size[cell->cur_batch];
+   free -= sizeof(struct cell_command_fence);
    return free;
 }
 

src/gallium/drivers/cell/ppu/cell_context.c

@@ -47,6 +47,7 @@
 #include "cell_clear.h"
 #include "cell_context.h"
 #include "cell_draw_arrays.h"
+#include "cell_fence.h"
 #include "cell_flush.h"
 #include "cell_state.h"
 #include "cell_surface.h"
@@ -104,6 +105,7 @@ cell_create_context(struct pipe_screen *screen,
                     struct cell_winsys *cws)
 {
    struct cell_context *cell;
+   uint i;
 
    /* some fields need to be 16-byte aligned, so align the whole object */
    cell = (struct cell_context*) align_malloc(sizeof(struct cell_context), 16);
@@ -151,6 +153,10 @@ cell_create_context(struct pipe_screen *screen,
                                               cell_debug_flags, 
                                               0 );
 
+   for (i = 0; i < CELL_NUM_BUFFERS; i++)
+      cell_fence_init(&cell->fenced_buffers[i].fence);
+
+
    /*
     * SPU stuff
     */

src/gallium/drivers/cell/ppu/cell_context.h

@@ -81,6 +81,19 @@ struct cell_fragment_ops_key
 };
 
 
+struct cell_buffer_node;
+
+/**
+ * Fenced buffer list.  List of buffers which can be unreferenced after
+ * the fence has been executed/signalled.
+ */
+struct cell_buffer_list
+{
+   struct cell_fence fence;
+   struct cell_buffer_node *head;
+};
+
+
 /**
  * Per-context state, subclass of pipe_context.
  */
@@ -154,6 +167,14 @@ struct cell_context
    uint buffer_status[CELL_MAX_SPUS][CELL_NUM_BUFFERS][4] ALIGN16_ATTRIB;
 
 
+   /** Associated with each command/batch buffer is a list of pipe_buffers
+    * that are fenced.  When the last command in a buffer is executed, the
+    * fence will be signalled, indicating that any pipe_buffers preceeding
+    * that fence can be unreferenced (and probably freed).
+    */
+   struct cell_buffer_list fenced_buffers[CELL_NUM_BUFFERS];
+
+
    struct spe_function attrib_fetch;
    unsigned attrib_fetch_offsets[PIPE_MAX_ATTRIBS];
 

src/gallium/drivers/cell/ppu/cell_fence.c

@@ -0,0 +1,158 @@
+/**************************************************************************
+ * 
+ * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
+ * All Rights Reserved.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ * 
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
+ * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ * 
+ **************************************************************************/
+
+#include <unistd.h>
+#include "util/u_memory.h"
+#include "pipe/p_inlines.h"
+#include "cell_context.h"
+#include "cell_batch.h"
+#include "cell_fence.h"
+#include "cell_texture.h"
+
+
+void
+cell_fence_init(struct cell_fence *fence)
+{
+   uint i;
+   for (i = 0; i < CELL_MAX_SPUS; i++) {
+      fence->status[i][0] = CELL_FENCE_IDLE;
+   }
+}
+
+
+boolean
+cell_fence_signalled(const struct cell_context *cell,
+                     const struct cell_fence *fence)
+{
+   uint i;
+   for (i = 0; i < cell->num_spus; i++) {
+      //ASSERT(fence->status[i][0] != CELL_FENCE_IDLE);
+      if (fence->status[i][0] == CELL_FENCE_EMITTED)
+         return FALSE;
+   }
+   return TRUE;
+}
+
+
+void
+cell_fence_finish(const struct cell_context *cell,
+                  const struct cell_fence *fence)
+{
+   while (!cell_fence_signalled(cell, fence)) {
+      usleep(10);
+   }
+}
+
+
+
+
+struct cell_buffer_node
+{
+   struct pipe_buffer *buffer;
+   struct cell_buffer_node *next;
+};
+
+
+static void
+cell_add_buffer_to_list(struct cell_context *cell,
+                        struct cell_buffer_list *list,
+                        struct pipe_buffer *buffer)
+{
+   struct pipe_screen *ps = cell->pipe.screen;
+   struct cell_buffer_node *node = CALLOC_STRUCT(cell_buffer_node);
+   /* create new list node which references the buffer, insert at head */
+   if (node) {
+      pipe_buffer_reference(ps, &node->buffer, buffer);
+      node->next = list->head;
+      list->head = node;
+   }
+}
+
+
+/**
+ * Wait for completion of the given fence, then unreference any buffers
+ * on the list.
+ * This typically unrefs/frees texture buffers after any rendering which uses
+ * them has completed.
+ */
+void
+cell_free_fenced_buffers(struct cell_context *cell,
+                         struct cell_buffer_list *list)
+{
+   if (list->head) {
+      struct pipe_screen *ps = cell->pipe.screen;
+      struct cell_buffer_node *node;
+
+      cell_fence_finish(cell, &list->fence);
+
+      /* traverse the list, unreferencing buffers, freeing nodes */
+      node = list->head;
+      while (node) {
+         struct cell_buffer_node *next = node->next;
+         assert(node->buffer);
+         pipe_buffer_unmap(ps, node->buffer);
+#if 0
+         printf("Unref buffer %p\n", node->buffer);
+         if (node->buffer->refcount == 1)
+            printf("   Delete!\n");
+#endif
+         pipe_buffer_reference(ps, &node->buffer, NULL);
+         FREE(node);
+         node = next;
+      }
+      list->head = NULL;
+   }
+}
+
+
+/**
+ * This should be called for each render command.
+ * Any texture buffers that are current bound will be added to a fenced
+ * list to be freed later when the fence is executed/signalled.
+ */
+void
+cell_add_fenced_textures(struct cell_context *cell)
+{
+   struct cell_buffer_list *list = &cell->fenced_buffers[cell->cur_batch];
+   uint i;
+
+   for (i = 0; i < cell->num_textures; i++) {
+      struct cell_texture *ct = cell->texture[i];
+      if (ct) {
+         uint level;
+         for (level = 0; level < CELL_MAX_TEXTURE_LEVELS; level++) {
+            if (ct->tiled_buffer[level]) {
+#if 0
+               printf("Adding texture %p buffer %p to list\n",
+                      ct, ct->tiled_buffer[level]);
+#endif
+               cell_add_buffer_to_list(cell, list, ct->tiled_buffer[level]);
+            }
+         }
+      }
+   }
+}

src/gallium/drivers/cell/ppu/cell_fence.h

@@ -0,0 +1,57 @@
+/**************************************************************************
+ * 
+ * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
+ * All Rights Reserved.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ * 
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
+ * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ * 
+ **************************************************************************/
+
+
+#ifndef CELL_FENCE_H
+#define CELL_FENCE_H
+
+
+extern void
+cell_fence_init(struct cell_fence *fence);
+
+
+extern boolean
+cell_fence_signalled(const struct cell_context *cell,
+                     const struct cell_fence *fence);
+
+
+extern void
+cell_fence_finish(const struct cell_context *cell,
+                  const struct cell_fence *fence);
+
+
+
+extern void
+cell_free_fenced_buffers(struct cell_context *cell,
+                         struct cell_buffer_list *list);
+
+
+extern void
+cell_add_fenced_textures(struct cell_context *cell);
+
+
+#endif /* CELL_FENCE_H */

src/gallium/drivers/cell/ppu/cell_state_emit.c

@@ -225,7 +225,7 @@ cell_emit_state(struct cell_context *cell)
             if (cell->texture[i]) {
                uint level;
                for (level = 0; level < CELL_MAX_TEXTURE_LEVELS; level++) {
-                  texture->start[level] = cell->texture[i]->tiled_data[level];
+                  texture->start[level] = cell->texture[i]->tiled_mapped[level];
                   texture->width[level] = cell->texture[i]->base.width[level];
                   texture->height[level] = cell->texture[i]->base.height[level];
                   texture->depth[level] = cell->texture[i]->base.depth[level];

src/gallium/drivers/cell/ppu/cell_texture.c

@@ -136,6 +136,9 @@ cell_texture_release(struct pipe_screen *screen,
        __FUNCTION__, (void *) *pt, (*pt)->refcount - 1);
    */
    if (--(*pt)->refcount <= 0) {
+      /* Delete this texture now.
+       * But note that the underlying pipe_buffer may linger...
+       */
       struct cell_texture *ct = cell_texture(*pt);
       uint i;
 
@@ -146,14 +149,12 @@ cell_texture_release(struct pipe_screen *screen,
       pipe_buffer_reference(screen, &ct->buffer, NULL);
 
       for (i = 0; i < CELL_MAX_TEXTURE_LEVELS; i++) {
-         if (ct->tiled_data[i]) {
-            /* XXX need to use a fenced buffer for tiled data so that
-             * it's properly freed after rendering has completed.
-             * Disabling this free() allows glDrawPixels to work for now.
-             */
-#if 0
-            align_free(ct->tiled_data[i]);
-#endif
+         /* Unreference the tiled image buffer.
+          * It may not actually be deleted until a fence is hit.
+          */
+         if (ct->tiled_buffer[i]) {
+            ct->tiled_mapped[i] = NULL;
+            winsys_buffer_reference(screen->winsys, &ct->tiled_buffer[i], NULL);
          }
       }
 
@@ -234,12 +235,18 @@ cell_twiddle_texture(struct pipe_screen *screen,
          int offset = bufWidth * bufHeight * 4 * surface->face;
          uint *dst;
 
-         if (!ct->tiled_data[level]) {
-            ct->tiled_data[level] =
-               align_malloc(bufWidth * bufHeight * 4 * numFaces, 16);
+         if (!ct->tiled_buffer[level]) {
+            /* allocate buffer for tiled data now */
+            struct pipe_winsys *ws = screen->winsys;
+            uint bytes = bufWidth * bufHeight * 4 * numFaces;
+            ct->tiled_buffer[level] = ws->buffer_create(ws, 16,
+                                                        PIPE_BUFFER_USAGE_PIXEL,
+                                                        bytes);
+            /* and map it */
+            ct->tiled_mapped[level] = ws->buffer_map(ws, ct->tiled_buffer[level],
+                                                     PIPE_BUFFER_USAGE_GPU_READ);
          }
-
-         dst = (uint *) ((ubyte *) ct->tiled_data[level] + offset);
+         dst = (uint *) ((ubyte *) ct->tiled_mapped[level] + offset);
 
          twiddle_image_uint(texWidth, texHeight, TILE_SIZE, dst,
                             surface->stride, src);

src/gallium/drivers/cell/ppu/cell_texture.h

@@ -48,7 +48,10 @@ struct cell_texture
    struct pipe_buffer *buffer;
    unsigned long buffer_size;
 
-   void *tiled_data[CELL_MAX_TEXTURE_LEVELS];  /* XXX this may be temporary */ /*ALIGN16*/
+   /** Texture data in tiled layout is held here */
+   struct pipe_buffer *tiled_buffer[CELL_MAX_TEXTURE_LEVELS];
+   /** Mapped, tiled texture data */
+   void *tiled_mapped[CELL_MAX_TEXTURE_LEVELS];
 };
 
 

src/gallium/drivers/cell/ppu/cell_vbuf.c

@@ -38,6 +38,7 @@
 
 #include "cell_batch.h"
 #include "cell_context.h"
+#include "cell_fence.h"
 #include "cell_flush.h"
 #include "cell_spu.h"
 #include "cell_vbuf.h"
@@ -108,6 +109,11 @@ cell_vbuf_release_vertices(struct vbuf_render *vbr, void *vertices,
           __FUNCTION__, cvbr->vertex_buf, vertices_used);
    */
 
+   /* Make sure texture buffers aren't released until we're done rendering
+    * with them.
+    */
+   cell_add_fenced_textures(cell);
+
    /* Tell SPUs they can release the vert buf */
    if (cvbr->vertex_buf != ~0U) {
       struct cell_command_release_verts *release

src/gallium/drivers/cell/spu/spu_command.c

@@ -76,9 +76,10 @@ static void
 release_buffer(uint buffer)
 {
    /* Evidently, using less than a 16-byte status doesn't work reliably */
-   static const uint status[4] ALIGN16_ATTRIB
-      = {CELL_BUFFER_STATUS_FREE, 0, 0, 0};
-
+   static const vector unsigned int status = {CELL_BUFFER_STATUS_FREE,
+                                              CELL_BUFFER_STATUS_FREE,
+                                              CELL_BUFFER_STATUS_FREE,
+                                              CELL_BUFFER_STATUS_FREE};
    const uint index = 4 * (spu.init.id * CELL_NUM_BUFFERS + buffer);
    uint *dst = spu.init.buffer_status + index;
 
@@ -93,6 +94,29 @@ release_buffer(uint buffer)
 }
 
 
+/**
+ * Write CELL_FENCE_SIGNALLED back to the fence status qword in main memory.
+ * There's a qword of status per SPU.
+ */
+static void
+cmd_fence(struct cell_command_fence *fence_cmd)
+{
+   static const vector unsigned int status = {CELL_FENCE_SIGNALLED,
+                                              CELL_FENCE_SIGNALLED,
+                                              CELL_FENCE_SIGNALLED,
+                                              CELL_FENCE_SIGNALLED};
+   uint *dst = (uint *) fence_cmd->fence;
+   dst += 4 * spu.init.id;  /* main store/memory address, not local store */
+
+   mfc_put((void *) &status,    /* src in local memory */
+           (unsigned int) dst,  /* dst in main memory */
+           sizeof(status),      /* size */
+           TAG_FENCE,           /* tag */
+           0, /* tid */
+           0  /* rid */);
+}
+
+
 static void
 cmd_clear_surface(const struct cell_command_clear_surface *clear)
 {
@@ -637,6 +661,14 @@ cmd_batch(uint opcode)
          cmd_finish();
          pos += 1;
          break;
+      case CELL_CMD_FENCE:
+         {
+            struct cell_command_fence *fence_cmd =
+               (struct cell_command_fence *) &buffer[pos];
+            cmd_fence(fence_cmd);
+            pos += sizeof(*fence_cmd) / 8;
+         }
+         break;
       case CELL_CMD_RELEASE_VERTS:
          {
             struct cell_command_release_verts *release

src/gallium/drivers/cell/spu/spu_main.h

@@ -210,7 +210,7 @@ extern struct spu_global spu;
 #define TAG_DCACHE1           21
 #define TAG_DCACHE2           22
 #define TAG_DCACHE3           23
-
+#define TAG_FENCE             24
 
 
 static INLINE void