drm/vbl rework: rework how the drm deals with vblank.

Other Authors: Michel Dänzer <michel@tungstengraphics.com>
mga: Ian Romanick <idr@us.ibm.com>
via: Thomas Hellstrom <thomas-at-tungstengraphics-dot-com>

This re-works the DRM internals to provide a better interface for drivers
to expose vblank on multiple crtcs.

It also includes work done by Michel on making i915 triple buffering and pageflipping work properly.

Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 119 insertions, 41 deletions

diff --git a/drivers/char/drm/i915_dma.c b/drivers/char/drm/i915_dma.c
index a043bb12301..ef7bf143a80 100644
--- a/drivers/char/drm/i915_dma.c
+++ b/drivers/char/drm/i915_dma.c
@@ -415,10 +415,13 @@ static void i915_emit_breadcrumb(struct drm_device *dev)
         drm_i915_private_t *dev_priv = dev->dev_private;
         RING_LOCALS;
 
-        dev_priv->sarea_priv->last_enqueue = ++dev_priv->counter;
+        if (++dev_priv->counter > BREADCRUMB_MASK) {
+                 dev_priv->counter = 1;
+                 DRM_DEBUG("Breadcrumb counter wrapped around\n");
+        }
 
-        if (dev_priv->counter > 0x7FFFFFFFUL)
-                dev_priv->sarea_priv->last_enqueue = dev_priv->counter = 1;
+        if (dev_priv->sarea_priv)
+                dev_priv->sarea_priv->last_enqueue = dev_priv->counter;
 
         BEGIN_LP_RING(4);
         OUT_RING(CMD_STORE_DWORD_IDX);
@@ -428,6 +431,26 @@ static void i915_emit_breadcrumb(struct drm_device *dev)
         ADVANCE_LP_RING();
 }
 
+int i915_emit_mi_flush(struct drm_device *dev, uint32_t flush)
+{
+        drm_i915_private_t *dev_priv = dev->dev_private;
+        uint32_t flush_cmd = CMD_MI_FLUSH;
+        RING_LOCALS;
+
+        flush_cmd |= flush;
+
+        i915_kernel_lost_context(dev);
+
+        BEGIN_LP_RING(4);
+        OUT_RING(flush_cmd);
+        OUT_RING(0);
+        OUT_RING(0);
+        OUT_RING(0);
+        ADVANCE_LP_RING();
+
+        return 0;
+}
+
 static int i915_dispatch_cmdbuffer(struct drm_device * dev,
                                    drm_i915_cmdbuffer_t * cmd)
 {
@@ -511,52 +534,74 @@ static int i915_dispatch_batchbuffer(struct drm_device * dev,
         return 0;
 }
 
-static int i915_dispatch_flip(struct drm_device * dev)
+static void i915_do_dispatch_flip(struct drm_device * dev, int plane, int sync)
 {
         drm_i915_private_t *dev_priv = dev->dev_private;
+        u32 num_pages, current_page, next_page, dspbase;
+        int shift = 2 * plane, x, y;
         RING_LOCALS;
 
-        DRM_DEBUG("%s: page=%d pfCurrentPage=%d\n",
-                  __FUNCTION__,
-                  dev_priv->current_page,
-                  dev_priv->sarea_priv->pf_current_page);
+        /* Calculate display base offset */
+        num_pages = dev_priv->sarea_priv->third_handle ? 3 : 2;
+        current_page = (dev_priv->sarea_priv->pf_current_page >> shift) & 0x3;
+        next_page = (current_page + 1) % num_pages;
 
-        i915_kernel_lost_context(dev);
-
-        BEGIN_LP_RING(2);
-        OUT_RING(INST_PARSER_CLIENT | INST_OP_FLUSH | INST_FLUSH_MAP_CACHE);
-        OUT_RING(0);
-        ADVANCE_LP_RING();
+        switch (next_page) {
+        default:
+        case 0:
+                dspbase = dev_priv->sarea_priv->front_offset;
+                break;
+        case 1:
+                dspbase = dev_priv->sarea_priv->back_offset;
+                break;
+        case 2:
+                dspbase = dev_priv->sarea_priv->third_offset;
+                break;
+        }
 
-        BEGIN_LP_RING(6);
-        OUT_RING(CMD_OP_DISPLAYBUFFER_INFO | ASYNC_FLIP);
-        OUT_RING(0);
-        if (dev_priv->current_page == 0) {
-                OUT_RING(dev_priv->back_offset);
-                dev_priv->current_page = 1;
+        if (plane == 0) {
+                x = dev_priv->sarea_priv->planeA_x;
+                y = dev_priv->sarea_priv->planeA_y;
         } else {
-                OUT_RING(dev_priv->front_offset);
-                dev_priv->current_page = 0;
+                x = dev_priv->sarea_priv->planeB_x;
+                y = dev_priv->sarea_priv->planeB_y;
         }
-        OUT_RING(0);
-        ADVANCE_LP_RING();
 
-        BEGIN_LP_RING(2);
-        OUT_RING(MI_WAIT_FOR_EVENT | MI_WAIT_FOR_PLANE_A_FLIP);
-        OUT_RING(0);
-        ADVANCE_LP_RING();
+        dspbase += (y * dev_priv->sarea_priv->pitch + x) * dev_priv->cpp;
 
-        dev_priv->sarea_priv->last_enqueue = dev_priv->counter++;
+        DRM_DEBUG("plane=%d current_page=%d dspbase=0x%x\n", plane, current_page,
+                  dspbase);
 
         BEGIN_LP_RING(4);
-        OUT_RING(CMD_STORE_DWORD_IDX);
-        OUT_RING(20);
-        OUT_RING(dev_priv->counter);
-        OUT_RING(0);
+        OUT_RING(sync ? 0 :
+                 (MI_WAIT_FOR_EVENT | (plane ? MI_WAIT_FOR_PLANE_B_FLIP :
+                                       MI_WAIT_FOR_PLANE_A_FLIP)));
+        OUT_RING(CMD_OP_DISPLAYBUFFER_INFO | (sync ? 0 : ASYNC_FLIP) |
+                 (plane ? DISPLAY_PLANE_B : DISPLAY_PLANE_A));
+        OUT_RING(dev_priv->sarea_priv->pitch * dev_priv->cpp);
+        OUT_RING(dspbase);
         ADVANCE_LP_RING();
 
-        dev_priv->sarea_priv->pf_current_page = dev_priv->current_page;
-        return 0;
+        dev_priv->sarea_priv->pf_current_page &= ~(0x3 << shift);
+        dev_priv->sarea_priv->pf_current_page |= next_page << shift;
+}
+
+void i915_dispatch_flip(struct drm_device * dev, int planes, int sync)
+{
+        drm_i915_private_t *dev_priv = dev->dev_private;
+        int i;
+
+        DRM_DEBUG("planes=0x%x pfCurrentPage=%d\n",
+                  planes, dev_priv->sarea_priv->pf_current_page);
+
+        i915_emit_mi_flush(dev, MI_READ_FLUSH | MI_EXE_FLUSH);
+
+        for (i = 0; i < 2; i++)
+                if (planes & (1 << i))
+                        i915_do_dispatch_flip(dev, i, sync);
+
+        i915_emit_breadcrumb(dev);
+
 }
 
 static int i915_quiescent(struct drm_device * dev)
@@ -579,7 +624,6 @@ static int i915_batchbuffer(struct drm_device *dev, void *data,
                             struct drm_file *file_priv)
 {
         drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
-        u32 *hw_status = dev_priv->hw_status_page;
         drm_i915_sarea_t *sarea_priv = (drm_i915_sarea_t *)
             dev_priv->sarea_priv;
         drm_i915_batchbuffer_t *batch = data;
@@ -602,7 +646,7 @@ static int i915_batchbuffer(struct drm_device *dev, void *data,
 
         ret = i915_dispatch_batchbuffer(dev, batch);
 
-        sarea_priv->last_dispatch = (int)hw_status[5];
+        sarea_priv->last_dispatch = READ_BREADCRUMB(dev_priv);
         return ret;
 }
 
@@ -610,7 +654,6 @@ static int i915_cmdbuffer(struct drm_device *dev, void *data,
                           struct drm_file *file_priv)
 {
         drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
-        u32 *hw_status = dev_priv->hw_status_page;
         drm_i915_sarea_t *sarea_priv = (drm_i915_sarea_t *)
             dev_priv->sarea_priv;
         drm_i915_cmdbuffer_t *cmdbuf = data;
@@ -635,18 +678,51 @@ static int i915_cmdbuffer(struct drm_device *dev, void *data,
                 return ret;
         }
 
-        sarea_priv->last_dispatch = (int)hw_status[5];
+        sarea_priv->last_dispatch = READ_BREADCRUMB(dev_priv);
+        return 0;
+}
+
+static int i915_do_cleanup_pageflip(struct drm_device * dev)
+{
+        drm_i915_private_t *dev_priv = dev->dev_private;
+        int i, planes, num_pages = dev_priv->sarea_priv->third_handle ? 3 : 2;
+
+        DRM_DEBUG("\n");
+
+        for (i = 0, planes = 0; i < 2; i++)
+                if (dev_priv->sarea_priv->pf_current_page & (0x3 << (2 * i))) {
+                        dev_priv->sarea_priv->pf_current_page =
+                                (dev_priv->sarea_priv->pf_current_page &
+                                 ~(0x3 << (2 * i))) | ((num_pages - 1) << (2 * i));
+
+                        planes |= 1 << i;
+                }
+
+        if (planes)
+                i915_dispatch_flip(dev, planes, 0);
+
         return 0;
 }
 
 static int i915_flip_bufs(struct drm_device *dev, void *data,
                           struct drm_file *file_priv)
 {
-        DRM_DEBUG("%s\n", __FUNCTION__);
+        drm_i915_flip_t *param = data;
+
+        DRM_DEBUG("\n");
 
         LOCK_TEST_WITH_RETURN(dev, file_priv);
 
-        return i915_dispatch_flip(dev);
+        /* This is really planes */
+        if (param->pipes & ~0x3) {
+                DRM_ERROR("Invalid planes 0x%x, only <= 0x3 is valid\n",
+                          param->pipes);
+                return -EINVAL;
+        }
+
+        i915_dispatch_flip(dev, param->pipes, 0);
+
+        return 0;
 }
 
 static int i915_getparam(struct drm_device *dev, void *data,
@@ -807,6 +883,8 @@ void i915_driver_lastclose(struct drm_device * dev)
         if (!dev_priv)
                 return;
 
+        if (drm_getsarea(dev) && dev_priv->sarea_priv)
+                i915_do_cleanup_pageflip(dev);
         if (dev_priv->agp_heap)
                 i915_mem_takedown(&(dev_priv->agp_heap));