[Mesa-dev] [PATCH 15/17] nvc0: handle the case where there are no framebuffer attachments

[Edward O'Callaghan]

From: Ilia Mirkin <imirkin at alum.mit.edu>

Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
Reviewed-by: Edward O'Callaghan <eocallaghan at alterapraxis.com>
---
 src/gallium/drivers/nouveau/nvc0/nvc0_program.c        |  7 +++++++
 src/gallium/drivers/nouveau/nvc0/nvc0_state_validate.c | 16 ++++++++++++++--
 src/gallium/drivers/nouveau/nvc0/nvc0_surface.c        |  4 ++++
 3 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/src/gallium/drivers/nouveau/nvc0/nvc0_program.c b/src/gallium/drivers/nouveau/nvc0/nvc0_program.c
index bc884d6..f17e215 100644
--- a/src/gallium/drivers/nouveau/nvc0/nvc0_program.c
+++ b/src/gallium/drivers/nouveau/nvc0/nvc0_program.c
@@ -456,6 +456,13 @@ nvc0_fp_gen_header(struct nvc0_program *fp, struct nv50_ir_prog_info *info)
          fp->hdr[18] |= 0xf << info->out[i].slot[0];
    }
 
+   /* TODO: figure out proper condition, but this makes things work when there
+    * are no "regular" outputs in the frag shader, used when there are no
+    * attachments.
+    */
+   if (info->numOutputs == 0)
+      fp->hdr[18] |= 0xf;
+
    fp->fp.early_z = info->prop.fp.earlyFragTests;
 
    return 0;
diff --git a/src/gallium/drivers/nouveau/nvc0/nvc0_state_validate.c b/src/gallium/drivers/nouveau/nvc0/nvc0_state_validate.c
index c0ed5c0..133fb31 100644
--- a/src/gallium/drivers/nouveau/nvc0/nvc0_state_validate.c
+++ b/src/gallium/drivers/nouveau/nvc0/nvc0_state_validate.c
@@ -74,12 +74,11 @@ nvc0_validate_fb(struct nvc0_context *nvc0)
     struct pipe_framebuffer_state *fb = &nvc0->framebuffer;
     unsigned i, ms;
     unsigned ms_mode = NVC0_3D_MULTISAMPLE_MODE_MS1;
+    unsigned nr_cbufs = fb->nr_cbufs;
     bool serialize = false;
 
     nouveau_bufctx_reset(nvc0->bufctx_3d, NVC0_BIND_3D_FB);
 
-    BEGIN_NVC0(push, NVC0_3D(RT_CONTROL), 1);
-    PUSH_DATA (push, (076543210 << 4) | fb->nr_cbufs);
     BEGIN_NVC0(push, NVC0_3D(SCREEN_SCISSOR_HORIZ), 2);
     PUSH_DATA (push, fb->width << 16);
     PUSH_DATA (push, fb->height << 16);
@@ -178,6 +177,18 @@ nvc0_validate_fb(struct nvc0_context *nvc0)
         PUSH_DATA (push, 0);
     }
 
+    if (nr_cbufs == 0 && !fb->zsbuf) {
+       unsigned samples = util_next_power_of_two(fb->samples);
+
+       nvc0_fb_set_null_rt(push, 0);
+
+       assert(samples <= 8);
+       ms_mode = ffs(samples) - 1;
+       nr_cbufs = 1;
+    }
+
+    BEGIN_NVC0(push, NVC0_3D(RT_CONTROL), 1);
+    PUSH_DATA (push, (076543210 << 4) | nr_cbufs);
     IMMED_NVC0(push, NVC0_3D(MULTISAMPLE_MODE), ms_mode);
 
     ms = 1 << ms_mode;
@@ -590,6 +601,7 @@ nvc0_validate_derived_2(struct nvc0_context *nvc0)
    struct nouveau_pushbuf *push = nvc0->base.pushbuf;
 
    if (nvc0->zsa && nvc0->zsa->pipe.alpha.enabled &&
+       nvc0->framebuffer.zsbuf &&
        nvc0->framebuffer.nr_cbufs == 0) {
       nvc0_fb_set_null_rt(push, 0);
       BEGIN_NVC0(push, NVC0_3D(RT_CONTROL), 1);
diff --git a/src/gallium/drivers/nouveau/nvc0/nvc0_surface.c b/src/gallium/drivers/nouveau/nvc0/nvc0_surface.c
index e8b3a4d..d546957 100644
--- a/src/gallium/drivers/nouveau/nvc0/nvc0_surface.c
+++ b/src/gallium/drivers/nouveau/nvc0/nvc0_surface.c
@@ -1043,6 +1043,8 @@ nvc0_blitctx_pre_blit(struct nvc0_blitctx *ctx)
 
    ctx->saved.fb.width = nvc0->framebuffer.width;
    ctx->saved.fb.height = nvc0->framebuffer.height;
+   ctx->saved.fb.samples = nvc0->framebuffer.samples;
+   ctx->saved.fb.layers = nvc0->framebuffer.layers;
    ctx->saved.fb.nr_cbufs = nvc0->framebuffer.nr_cbufs;
    ctx->saved.fb.cbufs[0] = nvc0->framebuffer.cbufs[0];
    ctx->saved.fb.zsbuf = nvc0->framebuffer.zsbuf;
@@ -1110,6 +1112,8 @@ nvc0_blitctx_post_blit(struct nvc0_blitctx *blit)
 
    nvc0->framebuffer.width = blit->saved.fb.width;
    nvc0->framebuffer.height = blit->saved.fb.height;
+   nvc0->framebuffer.samples = blit->saved.fb.samples;
+   nvc0->framebuffer.layers = blit->saved.fb.layers;
    nvc0->framebuffer.nr_cbufs = blit->saved.fb.nr_cbufs;
    nvc0->framebuffer.cbufs[0] = blit->saved.fb.cbufs[0];
    nvc0->framebuffer.zsbuf = blit->saved.fb.zsbuf;
-- 
2.5.0