drm/i915: Add a mechanism for pipelining fence register updates
Not employed just yet...
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 2cfdee8..1e9cf2b 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2322,7 +2322,8 @@
return 0;
}
-static void sandybridge_write_fence_reg(struct drm_i915_gem_object *obj)
+static int sandybridge_write_fence_reg(struct drm_i915_gem_object *obj,
+ struct intel_ring_buffer *pipelined)
{
struct drm_device *dev = obj->base.dev;
drm_i915_private_t *dev_priv = dev->dev_private;
@@ -2331,7 +2332,7 @@
uint64_t val;
val = (uint64_t)((obj->gtt_offset + size - 4096) &
- 0xfffff000) << 32;
+ 0xfffff000) << 32;
val |= obj->gtt_offset & 0xfffff000;
val |= (uint64_t)((obj->stride / 128) - 1) <<
SANDYBRIDGE_FENCE_PITCH_SHIFT;
@@ -2340,10 +2341,26 @@
val |= 1 << I965_FENCE_TILING_Y_SHIFT;
val |= I965_FENCE_REG_VALID;
- I915_WRITE64(FENCE_REG_SANDYBRIDGE_0 + (regnum * 8), val);
+ if (pipelined) {
+ int ret = intel_ring_begin(pipelined, 6);
+ if (ret)
+ return ret;
+
+ intel_ring_emit(pipelined, MI_NOOP);
+ intel_ring_emit(pipelined, MI_LOAD_REGISTER_IMM(2));
+ intel_ring_emit(pipelined, FENCE_REG_SANDYBRIDGE_0 + regnum*8);
+ intel_ring_emit(pipelined, (u32)val);
+ intel_ring_emit(pipelined, FENCE_REG_SANDYBRIDGE_0 + regnum*8 + 4);
+ intel_ring_emit(pipelined, (u32)(val >> 32));
+ intel_ring_advance(pipelined);
+ } else
+ I915_WRITE64(FENCE_REG_SANDYBRIDGE_0 + regnum * 8, val);
+
+ return 0;
}
-static void i965_write_fence_reg(struct drm_i915_gem_object *obj)
+static int i965_write_fence_reg(struct drm_i915_gem_object *obj,
+ struct intel_ring_buffer *pipelined)
{
struct drm_device *dev = obj->base.dev;
drm_i915_private_t *dev_priv = dev->dev_private;
@@ -2359,27 +2376,41 @@
val |= 1 << I965_FENCE_TILING_Y_SHIFT;
val |= I965_FENCE_REG_VALID;
- I915_WRITE64(FENCE_REG_965_0 + (regnum * 8), val);
+ if (pipelined) {
+ int ret = intel_ring_begin(pipelined, 6);
+ if (ret)
+ return ret;
+
+ intel_ring_emit(pipelined, MI_NOOP);
+ intel_ring_emit(pipelined, MI_LOAD_REGISTER_IMM(2));
+ intel_ring_emit(pipelined, FENCE_REG_965_0 + regnum*8);
+ intel_ring_emit(pipelined, (u32)val);
+ intel_ring_emit(pipelined, FENCE_REG_965_0 + regnum*8 + 4);
+ intel_ring_emit(pipelined, (u32)(val >> 32));
+ intel_ring_advance(pipelined);
+ } else
+ I915_WRITE64(FENCE_REG_965_0 + regnum * 8, val);
+
+ return 0;
}
-static void i915_write_fence_reg(struct drm_i915_gem_object *obj)
+static int i915_write_fence_reg(struct drm_i915_gem_object *obj,
+ struct intel_ring_buffer *pipelined)
{
struct drm_device *dev = obj->base.dev;
drm_i915_private_t *dev_priv = dev->dev_private;
u32 size = obj->gtt_space->size;
- uint32_t fence_reg, val, pitch_val;
+ u32 fence_reg, val, pitch_val;
int tile_width;
- if ((obj->gtt_offset & ~I915_FENCE_START_MASK) ||
- (obj->gtt_offset & (size - 1))) {
- WARN(1, "%s: object 0x%08x [fenceable? %d] not 1M or size (0x%08x) aligned [gtt_space offset=%lx, size=%lx]\n",
- __func__, obj->gtt_offset, obj->map_and_fenceable, size,
- obj->gtt_space->start, obj->gtt_space->size);
- return;
- }
+ if (WARN((obj->gtt_offset & ~I915_FENCE_START_MASK) ||
+ (size & -size) != size ||
+ (obj->gtt_offset & (size - 1)),
+ "object 0x%08x [fenceable? %d] not 1M or pot-size (0x%08x) aligned\n",
+ obj->gtt_offset, obj->map_and_fenceable, size))
+ return -EINVAL;
- if (obj->tiling_mode == I915_TILING_Y &&
- HAS_128_BYTE_Y_TILING(dev))
+ if (obj->tiling_mode == I915_TILING_Y && HAS_128_BYTE_Y_TILING(dev))
tile_width = 128;
else
tile_width = 512;
@@ -2388,12 +2419,6 @@
pitch_val = obj->stride / tile_width;
pitch_val = ffs(pitch_val) - 1;
- if (obj->tiling_mode == I915_TILING_Y &&
- HAS_128_BYTE_Y_TILING(dev))
- WARN_ON(pitch_val > I830_FENCE_MAX_PITCH_VAL);
- else
- WARN_ON(pitch_val > I915_FENCE_MAX_PITCH_VAL);
-
val = obj->gtt_offset;
if (obj->tiling_mode == I915_TILING_Y)
val |= 1 << I830_FENCE_TILING_Y_SHIFT;
@@ -2406,10 +2431,25 @@
fence_reg = FENCE_REG_830_0 + fence_reg * 4;
else
fence_reg = FENCE_REG_945_8 + (fence_reg - 8) * 4;
- I915_WRITE(fence_reg, val);
+
+ if (pipelined) {
+ int ret = intel_ring_begin(pipelined, 4);
+ if (ret)
+ return ret;
+
+ intel_ring_emit(pipelined, MI_NOOP);
+ intel_ring_emit(pipelined, MI_LOAD_REGISTER_IMM(1));
+ intel_ring_emit(pipelined, fence_reg);
+ intel_ring_emit(pipelined, val);
+ intel_ring_advance(pipelined);
+ } else
+ I915_WRITE(fence_reg, val);
+
+ return 0;
}
-static void i830_write_fence_reg(struct drm_i915_gem_object *obj)
+static int i830_write_fence_reg(struct drm_i915_gem_object *obj,
+ struct intel_ring_buffer *pipelined)
{
struct drm_device *dev = obj->base.dev;
drm_i915_private_t *dev_priv = dev->dev_private;
@@ -2417,29 +2457,38 @@
int regnum = obj->fence_reg;
uint32_t val;
uint32_t pitch_val;
- uint32_t fence_size_bits;
- if ((obj->gtt_offset & ~I830_FENCE_START_MASK) ||
- (obj->gtt_offset & (obj->base.size - 1))) {
- WARN(1, "%s: object 0x%08x not 512K or size aligned\n",
- __func__, obj->gtt_offset);
- return;
- }
+ if (WARN((obj->gtt_offset & ~I830_FENCE_START_MASK) ||
+ (size & -size) != size ||
+ (obj->gtt_offset & (size - 1)),
+ "object 0x%08x not 512K or pot-size 0x%08x aligned\n",
+ obj->gtt_offset, size))
+ return -EINVAL;
pitch_val = obj->stride / 128;
pitch_val = ffs(pitch_val) - 1;
- WARN_ON(pitch_val > I830_FENCE_MAX_PITCH_VAL);
val = obj->gtt_offset;
if (obj->tiling_mode == I915_TILING_Y)
val |= 1 << I830_FENCE_TILING_Y_SHIFT;
- fence_size_bits = I830_FENCE_SIZE_BITS(size);
- WARN_ON(fence_size_bits & ~0x00000f00);
- val |= fence_size_bits;
+ val |= I830_FENCE_SIZE_BITS(size);
val |= pitch_val << I830_FENCE_PITCH_SHIFT;
val |= I830_FENCE_REG_VALID;
- I915_WRITE(FENCE_REG_830_0 + (regnum * 4), val);
+ if (pipelined) {
+ int ret = intel_ring_begin(pipelined, 4);
+ if (ret)
+ return ret;
+
+ intel_ring_emit(pipelined, MI_NOOP);
+ intel_ring_emit(pipelined, MI_LOAD_REGISTER_IMM(1));
+ intel_ring_emit(pipelined, FENCE_REG_830_0 + regnum*4);
+ intel_ring_emit(pipelined, val);
+ intel_ring_advance(pipelined);
+ } else
+ I915_WRITE(FENCE_REG_830_0 + regnum * 4, val);
+
+ return 0;
}
static int i915_find_fence_reg(struct drm_device *dev,
@@ -2512,6 +2561,7 @@
struct drm_device *dev = obj->base.dev;
struct drm_i915_private *dev_priv = dev->dev_private;
struct drm_i915_fence_reg *reg = NULL;
+ struct intel_ring_buffer *pipelined = NULL;
int ret;
/* Just update our place in the LRU if our fence is getting used. */
@@ -2553,25 +2603,24 @@
switch (INTEL_INFO(dev)->gen) {
case 6:
- sandybridge_write_fence_reg(obj);
+ ret = sandybridge_write_fence_reg(obj, pipelined);
break;
case 5:
case 4:
- i965_write_fence_reg(obj);
+ ret = i965_write_fence_reg(obj, pipelined);
break;
case 3:
- i915_write_fence_reg(obj);
+ ret = i915_write_fence_reg(obj, pipelined);
break;
case 2:
- i830_write_fence_reg(obj);
+ ret = i830_write_fence_reg(obj, pipelined);
break;
}
trace_i915_gem_object_get_fence(obj,
obj->fence_reg,
obj->tiling_mode);
-
- return 0;
+ return ret;
}
/**
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index c668b2f..ce97471 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -164,7 +164,13 @@
#define MI_MEM_VIRTUAL (1 << 22) /* 965+ only */
#define MI_STORE_DWORD_INDEX MI_INSTR(0x21, 1)
#define MI_STORE_DWORD_INDEX_SHIFT 2
-#define MI_LOAD_REGISTER_IMM MI_INSTR(0x22, 1)
+/* Official intel docs are somewhat sloppy concerning MI_LOAD_REGISTER_IMM:
+ * - Always issue a MI_NOOP _before_ the MI_LOAD_REGISTER_IMM - otherwise hw
+ * simply ignores the register load under certain conditions.
+ * - One can actually load arbitrary many arbitrary registers: Simply issue x
+ * address/value pairs. Don't overdue it, though, x <= 2^4 must hold!
+ */
+#define MI_LOAD_REGISTER_IMM(x) MI_INSTR(0x22, 2*x-1)
#define MI_FLUSH_DW MI_INSTR(0x26, 2) /* for GEN6 */
#define MI_BATCH_BUFFER MI_INSTR(0x30, 1)
#define MI_BATCH_NON_SECURE (1)