drm/i915: add fence register management to execbuf
Adds code to set up fence registers at execbuf time on pre-965 chips as
necessary. Also fixes up a few bugs in the pre-965 tile register support
(get_order != ffs). The number of fences available to the kernel defaults
to the hw limit minus 3 (for legacy X front/back/depth), but a new parameter
allows userspace to override that as needed.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@linux.ie>
diff --git a/drivers/gpu/drm/i915/i915_gem_tiling.c b/drivers/gpu/drm/i915/i915_gem_tiling.c
index 241f39b..2534c79 100644
--- a/drivers/gpu/drm/i915/i915_gem_tiling.c
+++ b/drivers/gpu/drm/i915/i915_gem_tiling.c
@@ -173,6 +173,73 @@
dev_priv->mm.bit_6_swizzle_y = swizzle_y;
}
+
+/**
+ * Returns the size of the fence for a tiled object of the given size.
+ */
+static int
+i915_get_fence_size(struct drm_device *dev, int size)
+{
+ int i;
+ int start;
+
+ if (IS_I965G(dev)) {
+ /* The 965 can have fences at any page boundary. */
+ return ALIGN(size, 4096);
+ } else {
+ /* Align the size to a power of two greater than the smallest
+ * fence size.
+ */
+ if (IS_I9XX(dev))
+ start = 1024 * 1024;
+ else
+ start = 512 * 1024;
+
+ for (i = start; i < size; i <<= 1)
+ ;
+
+ return i;
+ }
+}
+
+/* Check pitch constriants for all chips & tiling formats */
+static bool
+i915_tiling_ok(struct drm_device *dev, int stride, int size, int tiling_mode)
+{
+ int tile_width;
+
+ /* Linear is always fine */
+ if (tiling_mode == I915_TILING_NONE)
+ return true;
+
+ if (tiling_mode == I915_TILING_Y && HAS_128_BYTE_Y_TILING(dev))
+ tile_width = 128;
+ else
+ tile_width = 512;
+
+ /* 965+ just needs multiples of tile width */
+ if (IS_I965G(dev)) {
+ if (stride & (tile_width - 1))
+ return false;
+ return true;
+ }
+
+ /* Pre-965 needs power of two tile widths */
+ if (stride < tile_width)
+ return false;
+
+ if (stride & (stride - 1))
+ return false;
+
+ /* We don't handle the aperture area covered by the fence being bigger
+ * than the object size.
+ */
+ if (i915_get_fence_size(dev, size) != size)
+ return false;
+
+ return true;
+}
+
/**
* Sets the tiling mode of an object, returning the required swizzling of
* bit 6 of addresses in the object.
@@ -191,6 +258,9 @@
return -EINVAL;
obj_priv = obj->driver_private;
+ if (!i915_tiling_ok(dev, args->stride, obj->size, args->tiling_mode))
+ return -EINVAL;
+
mutex_lock(&dev->struct_mutex);
if (args->tiling_mode == I915_TILING_NONE) {
@@ -207,7 +277,23 @@
args->swizzle_mode = I915_BIT_6_SWIZZLE_NONE;
}
}
- obj_priv->tiling_mode = args->tiling_mode;
+ if (args->tiling_mode != obj_priv->tiling_mode) {
+ int ret;
+
+ /* Unbind the object, as switching tiling means we're
+ * switching the cache organization due to fencing, probably.
+ */
+ ret = i915_gem_object_unbind(obj);
+ if (ret != 0) {
+ WARN(ret != -ERESTARTSYS,
+ "failed to unbind object for tiling switch");
+ args->tiling_mode = obj_priv->tiling_mode;
+ mutex_unlock(&dev->struct_mutex);
+
+ return ret;
+ }
+ obj_priv->tiling_mode = args->tiling_mode;
+ }
obj_priv->stride = args->stride;
mutex_unlock(&dev->struct_mutex);