[Mesa-dev] [PATCH] nv50, nvc0: fix start_instance in manual push path

[Ilia Mirkin]

The start instance is applied as an offset into the buffer directly,
ignoring the divisor, not as an instance id offset that respects the
divisor.

Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
Cc: "11.2 12.0" <mesa-stable at lists.freedesktop.org>
---
 src/gallium/drivers/nouveau/nv50/nv50_push.c          | 10 +++++++---
 src/gallium/drivers/nouveau/nvc0/nvc0_vbo_translate.c | 12 +++++++-----
 2 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/src/gallium/drivers/nouveau/nv50/nv50_push.c b/src/gallium/drivers/nouveau/nv50/nv50_push.c
index cbef95d..af27fb8 100644
--- a/src/gallium/drivers/nouveau/nv50/nv50_push.c
+++ b/src/gallium/drivers/nouveau/nv50/nv50_push.c
@@ -247,6 +247,7 @@ nv50_push_vbo(struct nv50_context *nv50, const struct pipe_draw_info *info)
    ctx.need_vertex_id = nv50->screen->base.class_3d >= NV84_3D_CLASS &&
       nv50->vertprog->vp.need_vertex_id && (nv50->vertex->num_elements < 32);
    ctx.index_bias = info->index_bias;
+   ctx.instance_id = 0;
 
    /* For indexed draws, gl_VertexID must be emitted for every vertex. */
    ctx.packet_vertex_limit =
@@ -264,8 +265,12 @@ nv50_push_vbo(struct nv50_context *nv50, const struct pipe_draw_info *info)
       else
          data = vb->user_buffer;
 
-      if (apply_bias && likely(!(nv50->vertex->instance_bufs & (1 << i))))
-         data += (ptrdiff_t)info->index_bias * vb->stride;
+      if (likely(!(nv50->vertex->instance_bufs & (1 << i)))) {
+         if (apply_bias)
+            data += (ptrdiff_t)info->index_bias * vb->stride;
+      } else {
+         data += (ptrdiff_t)info->start_instance * vb->stride;
+      }
 
       ctx.translate->set_buffer(ctx.translate, i, data, vb->stride, ~0);
    }
@@ -301,7 +306,6 @@ nv50_push_vbo(struct nv50_context *nv50, const struct pipe_draw_info *info)
       ctx.restart_index = 0;
    }
 
-   ctx.instance_id = info->start_instance;
    ctx.prim = nv50_prim_gl(info->mode);
 
    if (info->primitive_restart) {
diff --git a/src/gallium/drivers/nouveau/nvc0/nvc0_vbo_translate.c b/src/gallium/drivers/nouveau/nvc0/nvc0_vbo_translate.c
index 20b6742..2f4e8b6 100644
--- a/src/gallium/drivers/nouveau/nvc0/nvc0_vbo_translate.c
+++ b/src/gallium/drivers/nouveau/nvc0/nvc0_vbo_translate.c
@@ -44,6 +44,7 @@ nvc0_push_context_init(struct nvc0_context *nvc0, struct push_context *ctx)
 
    ctx->translate = nvc0->vertex->translate;
    ctx->vertex_size = nvc0->vertex->size;
+   ctx->instance_id = 0;
 
    ctx->need_vertex_id =
       nvc0->vertprog->vp.need_vertex_id && (nvc0->vertex->num_elements < 32);
@@ -58,7 +59,8 @@ nvc0_push_context_init(struct nvc0_context *nvc0, struct push_context *ctx)
 }
 
 static inline void
-nvc0_vertex_configure_translate(struct nvc0_context *nvc0, int32_t index_bias)
+nvc0_vertex_configure_translate(struct nvc0_context *nvc0, int32_t index_bias,
+                                uint32_t start_instance)
 {
    struct translate *translate = nvc0->vertex->translate;
    unsigned i;
@@ -73,8 +75,10 @@ nvc0_vertex_configure_translate(struct nvc0_context *nvc0, int32_t index_bias)
          map = nouveau_resource_map_offset(&nvc0->base,
             nv04_resource(vb->buffer), vb->buffer_offset, NOUVEAU_BO_RD);
 
-      if (index_bias && !unlikely(nvc0->vertex->instance_bufs & (1 << i)))
+      if (!unlikely(nvc0->vertex->instance_bufs & (1 << i)))
          map += (intptr_t)index_bias * vb->stride;
+      else
+         map += (intptr_t)start_instance * vb->stride;
 
       translate->set_buffer(translate, i, map, vb->stride, ~0);
    }
@@ -470,7 +474,7 @@ nvc0_push_vbo(struct nvc0_context *nvc0, const struct pipe_draw_info *info)
 
    nvc0_push_context_init(nvc0, &ctx);
 
-   nvc0_vertex_configure_translate(nvc0, info->index_bias);
+   nvc0_vertex_configure_translate(nvc0, info->index_bias, info->start_instance);
 
    if (nvc0->state.index_bias) {
       /* this is already taken care of by translate */
@@ -515,8 +519,6 @@ nvc0_push_vbo(struct nvc0_context *nvc0, const struct pipe_draw_info *info)
       index_size = 0;
    }
 
-   ctx.instance_id = info->start_instance;
-
    prim = nvc0_prim_gl(info->mode);
    do {
       PUSH_SPACE(ctx.push, 9);
-- 
2.7.3