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![Dave Airlie](/assets/img/avatar_default.png)
-----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAABAgAGBQJWZMgaAAoJEHm+PkMAQRiGGcIH+gNS/hbN2DKW7wphl1QuaV7C 1fror8AvpwbGa/o0yuxovaVuZzAR0TF31vn+gAemF4U/hnM25xqxEHXYZEVv8OWw mbz4/z+jbVk3SiS5AiZPIZgL4W6RZnG5QYfiTVGPlBHuBznW2ITlNlClBOmBL45o uhb3bjTzi70AZ7Gh6i9sHgJoHg6D9u/ZxLaLcWnM79BzyTMHTf2t0wnrQmh66lEE hp7Rn9wXv9bk/e3iH7CVUb97P4IWhhkmfqcoturqAg9+C/M26b0VmvQp9Sy8S6Pd FVQ+SUIZllj5ZDKe9mOcs37czlxTr0keEFqzWeMh/7y4iuI3RaRp/qb+7mX5sIE= =WGZ1 -----END PGP SIGNATURE----- Back merge tag 'v4.4-rc4' into drm-next We've picked up a few conflicts and it would be nice to resolve them before we move onwards.
800 lines
25 KiB
C
800 lines
25 KiB
C
/*
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* Copyright © 2008-2015 Intel Corporation
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*
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* Permission is hereby granted, free of charge, to any person obtaining a
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* copy of this software and associated documentation files (the "Software"),
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* to deal in the Software without restriction, including without limitation
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* the rights to use, copy, modify, merge, publish, distribute, sublicense,
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* and/or sell copies of the Software, and to permit persons to whom the
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* Software is furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice (including the next
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* paragraph) shall be included in all copies or substantial portions of the
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* Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
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* IN THE SOFTWARE.
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*/
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#include <drm/drmP.h>
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#include <drm/i915_drm.h>
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#include "i915_drv.h"
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/**
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* DOC: fence register handling
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*
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* Important to avoid confusions: "fences" in the i915 driver are not execution
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* fences used to track command completion but hardware detiler objects which
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* wrap a given range of the global GTT. Each platform has only a fairly limited
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* set of these objects.
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*
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* Fences are used to detile GTT memory mappings. They're also connected to the
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* hardware frontbuffer render tracking and hence interract with frontbuffer
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* conmpression. Furthermore on older platforms fences are required for tiled
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* objects used by the display engine. They can also be used by the render
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* engine - they're required for blitter commands and are optional for render
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* commands. But on gen4+ both display (with the exception of fbc) and rendering
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* have their own tiling state bits and don't need fences.
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*
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* Also note that fences only support X and Y tiling and hence can't be used for
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* the fancier new tiling formats like W, Ys and Yf.
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*
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* Finally note that because fences are such a restricted resource they're
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* dynamically associated with objects. Furthermore fence state is committed to
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* the hardware lazily to avoid unecessary stalls on gen2/3. Therefore code must
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* explictly call i915_gem_object_get_fence() to synchronize fencing status
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* for cpu access. Also note that some code wants an unfenced view, for those
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* cases the fence can be removed forcefully with i915_gem_object_put_fence().
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*
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* Internally these functions will synchronize with userspace access by removing
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* CPU ptes into GTT mmaps (not the GTT ptes themselves) as needed.
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*/
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static void i965_write_fence_reg(struct drm_device *dev, int reg,
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struct drm_i915_gem_object *obj)
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{
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struct drm_i915_private *dev_priv = dev->dev_private;
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i915_reg_t fence_reg_lo, fence_reg_hi;
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int fence_pitch_shift;
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if (INTEL_INFO(dev)->gen >= 6) {
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fence_reg_lo = FENCE_REG_GEN6_LO(reg);
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fence_reg_hi = FENCE_REG_GEN6_HI(reg);
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fence_pitch_shift = GEN6_FENCE_PITCH_SHIFT;
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} else {
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fence_reg_lo = FENCE_REG_965_LO(reg);
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fence_reg_hi = FENCE_REG_965_HI(reg);
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fence_pitch_shift = I965_FENCE_PITCH_SHIFT;
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}
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/* To w/a incoherency with non-atomic 64-bit register updates,
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* we split the 64-bit update into two 32-bit writes. In order
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* for a partial fence not to be evaluated between writes, we
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* precede the update with write to turn off the fence register,
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* and only enable the fence as the last step.
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*
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* For extra levels of paranoia, we make sure each step lands
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* before applying the next step.
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*/
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I915_WRITE(fence_reg_lo, 0);
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POSTING_READ(fence_reg_lo);
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if (obj) {
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u32 size = i915_gem_obj_ggtt_size(obj);
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uint64_t val;
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/* Adjust fence size to match tiled area */
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if (obj->tiling_mode != I915_TILING_NONE) {
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uint32_t row_size = obj->stride *
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(obj->tiling_mode == I915_TILING_Y ? 32 : 8);
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size = (size / row_size) * row_size;
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}
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val = (uint64_t)((i915_gem_obj_ggtt_offset(obj) + size - 4096) &
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0xfffff000) << 32;
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val |= i915_gem_obj_ggtt_offset(obj) & 0xfffff000;
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val |= (uint64_t)((obj->stride / 128) - 1) << fence_pitch_shift;
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if (obj->tiling_mode == I915_TILING_Y)
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val |= 1 << I965_FENCE_TILING_Y_SHIFT;
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val |= I965_FENCE_REG_VALID;
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I915_WRITE(fence_reg_hi, val >> 32);
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POSTING_READ(fence_reg_hi);
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I915_WRITE(fence_reg_lo, val);
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POSTING_READ(fence_reg_lo);
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} else {
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I915_WRITE(fence_reg_hi, 0);
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POSTING_READ(fence_reg_hi);
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}
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}
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static void i915_write_fence_reg(struct drm_device *dev, int reg,
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struct drm_i915_gem_object *obj)
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{
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struct drm_i915_private *dev_priv = dev->dev_private;
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u32 val;
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if (obj) {
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u32 size = i915_gem_obj_ggtt_size(obj);
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int pitch_val;
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int tile_width;
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WARN((i915_gem_obj_ggtt_offset(obj) & ~I915_FENCE_START_MASK) ||
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(size & -size) != size ||
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(i915_gem_obj_ggtt_offset(obj) & (size - 1)),
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"object 0x%08llx [fenceable? %d] not 1M or pot-size (0x%08x) aligned\n",
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i915_gem_obj_ggtt_offset(obj), obj->map_and_fenceable, size);
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if (obj->tiling_mode == I915_TILING_Y && HAS_128_BYTE_Y_TILING(dev))
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tile_width = 128;
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else
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tile_width = 512;
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/* Note: pitch better be a power of two tile widths */
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pitch_val = obj->stride / tile_width;
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pitch_val = ffs(pitch_val) - 1;
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val = i915_gem_obj_ggtt_offset(obj);
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if (obj->tiling_mode == I915_TILING_Y)
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val |= 1 << I830_FENCE_TILING_Y_SHIFT;
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val |= I915_FENCE_SIZE_BITS(size);
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val |= pitch_val << I830_FENCE_PITCH_SHIFT;
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val |= I830_FENCE_REG_VALID;
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} else
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val = 0;
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I915_WRITE(FENCE_REG(reg), val);
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POSTING_READ(FENCE_REG(reg));
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}
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static void i830_write_fence_reg(struct drm_device *dev, int reg,
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struct drm_i915_gem_object *obj)
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{
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struct drm_i915_private *dev_priv = dev->dev_private;
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uint32_t val;
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if (obj) {
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u32 size = i915_gem_obj_ggtt_size(obj);
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uint32_t pitch_val;
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WARN((i915_gem_obj_ggtt_offset(obj) & ~I830_FENCE_START_MASK) ||
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(size & -size) != size ||
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(i915_gem_obj_ggtt_offset(obj) & (size - 1)),
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"object 0x%08llx not 512K or pot-size 0x%08x aligned\n",
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i915_gem_obj_ggtt_offset(obj), size);
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pitch_val = obj->stride / 128;
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pitch_val = ffs(pitch_val) - 1;
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val = i915_gem_obj_ggtt_offset(obj);
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if (obj->tiling_mode == I915_TILING_Y)
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val |= 1 << I830_FENCE_TILING_Y_SHIFT;
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val |= I830_FENCE_SIZE_BITS(size);
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val |= pitch_val << I830_FENCE_PITCH_SHIFT;
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val |= I830_FENCE_REG_VALID;
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} else
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val = 0;
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I915_WRITE(FENCE_REG(reg), val);
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POSTING_READ(FENCE_REG(reg));
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}
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inline static bool i915_gem_object_needs_mb(struct drm_i915_gem_object *obj)
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{
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return obj && obj->base.read_domains & I915_GEM_DOMAIN_GTT;
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}
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static void i915_gem_write_fence(struct drm_device *dev, int reg,
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struct drm_i915_gem_object *obj)
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{
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struct drm_i915_private *dev_priv = dev->dev_private;
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/* Ensure that all CPU reads are completed before installing a fence
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* and all writes before removing the fence.
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*/
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if (i915_gem_object_needs_mb(dev_priv->fence_regs[reg].obj))
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mb();
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WARN(obj && (!obj->stride || !obj->tiling_mode),
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"bogus fence setup with stride: 0x%x, tiling mode: %i\n",
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obj->stride, obj->tiling_mode);
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if (IS_GEN2(dev))
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i830_write_fence_reg(dev, reg, obj);
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else if (IS_GEN3(dev))
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i915_write_fence_reg(dev, reg, obj);
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else if (INTEL_INFO(dev)->gen >= 4)
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i965_write_fence_reg(dev, reg, obj);
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/* And similarly be paranoid that no direct access to this region
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* is reordered to before the fence is installed.
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*/
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if (i915_gem_object_needs_mb(obj))
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mb();
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}
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static inline int fence_number(struct drm_i915_private *dev_priv,
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struct drm_i915_fence_reg *fence)
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{
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return fence - dev_priv->fence_regs;
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}
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static void i915_gem_object_update_fence(struct drm_i915_gem_object *obj,
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struct drm_i915_fence_reg *fence,
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bool enable)
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{
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struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
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int reg = fence_number(dev_priv, fence);
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i915_gem_write_fence(obj->base.dev, reg, enable ? obj : NULL);
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if (enable) {
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obj->fence_reg = reg;
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fence->obj = obj;
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list_move_tail(&fence->lru_list, &dev_priv->mm.fence_list);
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} else {
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obj->fence_reg = I915_FENCE_REG_NONE;
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fence->obj = NULL;
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list_del_init(&fence->lru_list);
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}
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obj->fence_dirty = false;
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}
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static inline void i915_gem_object_fence_lost(struct drm_i915_gem_object *obj)
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{
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if (obj->tiling_mode)
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i915_gem_release_mmap(obj);
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/* As we do not have an associated fence register, we will force
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* a tiling change if we ever need to acquire one.
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*/
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obj->fence_dirty = false;
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obj->fence_reg = I915_FENCE_REG_NONE;
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}
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static int
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i915_gem_object_wait_fence(struct drm_i915_gem_object *obj)
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{
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if (obj->last_fenced_req) {
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int ret = i915_wait_request(obj->last_fenced_req);
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if (ret)
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return ret;
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i915_gem_request_assign(&obj->last_fenced_req, NULL);
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}
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return 0;
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}
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/**
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* i915_gem_object_put_fence - force-remove fence for an object
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* @obj: object to map through a fence reg
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*
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* This function force-removes any fence from the given object, which is useful
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* if the kernel wants to do untiled GTT access.
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*
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* Returns:
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*
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* 0 on success, negative error code on failure.
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*/
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int
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i915_gem_object_put_fence(struct drm_i915_gem_object *obj)
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{
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struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
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struct drm_i915_fence_reg *fence;
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int ret;
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ret = i915_gem_object_wait_fence(obj);
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if (ret)
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return ret;
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if (obj->fence_reg == I915_FENCE_REG_NONE)
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return 0;
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fence = &dev_priv->fence_regs[obj->fence_reg];
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if (WARN_ON(fence->pin_count))
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return -EBUSY;
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i915_gem_object_fence_lost(obj);
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i915_gem_object_update_fence(obj, fence, false);
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return 0;
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}
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static struct drm_i915_fence_reg *
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i915_find_fence_reg(struct drm_device *dev)
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{
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struct drm_i915_private *dev_priv = dev->dev_private;
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struct drm_i915_fence_reg *reg, *avail;
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int i;
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/* First try to find a free reg */
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avail = NULL;
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for (i = 0; i < dev_priv->num_fence_regs; i++) {
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reg = &dev_priv->fence_regs[i];
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if (!reg->obj)
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return reg;
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if (!reg->pin_count)
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avail = reg;
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}
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if (avail == NULL)
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goto deadlock;
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/* None available, try to steal one or wait for a user to finish */
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list_for_each_entry(reg, &dev_priv->mm.fence_list, lru_list) {
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if (reg->pin_count)
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continue;
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return reg;
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}
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deadlock:
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/* Wait for completion of pending flips which consume fences */
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if (intel_has_pending_fb_unpin(dev))
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return ERR_PTR(-EAGAIN);
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return ERR_PTR(-EDEADLK);
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}
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/**
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* i915_gem_object_get_fence - set up fencing for an object
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* @obj: object to map through a fence reg
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*
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* When mapping objects through the GTT, userspace wants to be able to write
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* to them without having to worry about swizzling if the object is tiled.
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* This function walks the fence regs looking for a free one for @obj,
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* stealing one if it can't find any.
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*
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* It then sets up the reg based on the object's properties: address, pitch
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* and tiling format.
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*
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* For an untiled surface, this removes any existing fence.
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*
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* Returns:
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*
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* 0 on success, negative error code on failure.
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*/
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int
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i915_gem_object_get_fence(struct drm_i915_gem_object *obj)
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{
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struct drm_device *dev = obj->base.dev;
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struct drm_i915_private *dev_priv = dev->dev_private;
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bool enable = obj->tiling_mode != I915_TILING_NONE;
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struct drm_i915_fence_reg *reg;
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int ret;
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/* Have we updated the tiling parameters upon the object and so
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* will need to serialise the write to the associated fence register?
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*/
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if (obj->fence_dirty) {
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ret = i915_gem_object_wait_fence(obj);
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if (ret)
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return ret;
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}
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/* Just update our place in the LRU if our fence is getting reused. */
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if (obj->fence_reg != I915_FENCE_REG_NONE) {
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reg = &dev_priv->fence_regs[obj->fence_reg];
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if (!obj->fence_dirty) {
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list_move_tail(®->lru_list,
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&dev_priv->mm.fence_list);
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return 0;
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}
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} else if (enable) {
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if (WARN_ON(!obj->map_and_fenceable))
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return -EINVAL;
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reg = i915_find_fence_reg(dev);
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if (IS_ERR(reg))
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return PTR_ERR(reg);
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if (reg->obj) {
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struct drm_i915_gem_object *old = reg->obj;
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ret = i915_gem_object_wait_fence(old);
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if (ret)
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return ret;
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i915_gem_object_fence_lost(old);
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}
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} else
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return 0;
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i915_gem_object_update_fence(obj, reg, enable);
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return 0;
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}
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/**
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* i915_gem_object_pin_fence - pin fencing state
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* @obj: object to pin fencing for
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*
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* This pins the fencing state (whether tiled or untiled) to make sure the
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* object is ready to be used as a scanout target. Fencing status must be
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* synchronize first by calling i915_gem_object_get_fence():
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*
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* The resulting fence pin reference must be released again with
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* i915_gem_object_unpin_fence().
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*
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* Returns:
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*
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* True if the object has a fence, false otherwise.
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*/
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bool
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i915_gem_object_pin_fence(struct drm_i915_gem_object *obj)
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{
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if (obj->fence_reg != I915_FENCE_REG_NONE) {
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struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
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struct i915_vma *ggtt_vma = i915_gem_obj_to_ggtt(obj);
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WARN_ON(!ggtt_vma ||
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dev_priv->fence_regs[obj->fence_reg].pin_count >
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ggtt_vma->pin_count);
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dev_priv->fence_regs[obj->fence_reg].pin_count++;
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return true;
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} else
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return false;
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}
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/**
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* i915_gem_object_unpin_fence - unpin fencing state
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* @obj: object to unpin fencing for
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*
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* This releases the fence pin reference acquired through
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* i915_gem_object_pin_fence. It will handle both objects with and without an
|
|
* attached fence correctly, callers do not need to distinguish this.
|
|
*/
|
|
void
|
|
i915_gem_object_unpin_fence(struct drm_i915_gem_object *obj)
|
|
{
|
|
if (obj->fence_reg != I915_FENCE_REG_NONE) {
|
|
struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
|
|
WARN_ON(dev_priv->fence_regs[obj->fence_reg].pin_count <= 0);
|
|
dev_priv->fence_regs[obj->fence_reg].pin_count--;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* i915_gem_restore_fences - restore fence state
|
|
* @dev: DRM device
|
|
*
|
|
* Restore the hw fence state to match the software tracking again, to be called
|
|
* after a gpu reset and on resume.
|
|
*/
|
|
void i915_gem_restore_fences(struct drm_device *dev)
|
|
{
|
|
struct drm_i915_private *dev_priv = dev->dev_private;
|
|
int i;
|
|
|
|
for (i = 0; i < dev_priv->num_fence_regs; i++) {
|
|
struct drm_i915_fence_reg *reg = &dev_priv->fence_regs[i];
|
|
|
|
/*
|
|
* Commit delayed tiling changes if we have an object still
|
|
* attached to the fence, otherwise just clear the fence.
|
|
*/
|
|
if (reg->obj) {
|
|
i915_gem_object_update_fence(reg->obj, reg,
|
|
reg->obj->tiling_mode);
|
|
} else {
|
|
i915_gem_write_fence(dev, i, NULL);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* DOC: tiling swizzling details
|
|
*
|
|
* The idea behind tiling is to increase cache hit rates by rearranging
|
|
* pixel data so that a group of pixel accesses are in the same cacheline.
|
|
* Performance improvement from doing this on the back/depth buffer are on
|
|
* the order of 30%.
|
|
*
|
|
* Intel architectures make this somewhat more complicated, though, by
|
|
* adjustments made to addressing of data when the memory is in interleaved
|
|
* mode (matched pairs of DIMMS) to improve memory bandwidth.
|
|
* For interleaved memory, the CPU sends every sequential 64 bytes
|
|
* to an alternate memory channel so it can get the bandwidth from both.
|
|
*
|
|
* The GPU also rearranges its accesses for increased bandwidth to interleaved
|
|
* memory, and it matches what the CPU does for non-tiled. However, when tiled
|
|
* it does it a little differently, since one walks addresses not just in the
|
|
* X direction but also Y. So, along with alternating channels when bit
|
|
* 6 of the address flips, it also alternates when other bits flip -- Bits 9
|
|
* (every 512 bytes, an X tile scanline) and 10 (every two X tile scanlines)
|
|
* are common to both the 915 and 965-class hardware.
|
|
*
|
|
* The CPU also sometimes XORs in higher bits as well, to improve
|
|
* bandwidth doing strided access like we do so frequently in graphics. This
|
|
* is called "Channel XOR Randomization" in the MCH documentation. The result
|
|
* is that the CPU is XORing in either bit 11 or bit 17 to bit 6 of its address
|
|
* decode.
|
|
*
|
|
* All of this bit 6 XORing has an effect on our memory management,
|
|
* as we need to make sure that the 3d driver can correctly address object
|
|
* contents.
|
|
*
|
|
* If we don't have interleaved memory, all tiling is safe and no swizzling is
|
|
* required.
|
|
*
|
|
* When bit 17 is XORed in, we simply refuse to tile at all. Bit
|
|
* 17 is not just a page offset, so as we page an objet out and back in,
|
|
* individual pages in it will have different bit 17 addresses, resulting in
|
|
* each 64 bytes being swapped with its neighbor!
|
|
*
|
|
* Otherwise, if interleaved, we have to tell the 3d driver what the address
|
|
* swizzling it needs to do is, since it's writing with the CPU to the pages
|
|
* (bit 6 and potentially bit 11 XORed in), and the GPU is reading from the
|
|
* pages (bit 6, 9, and 10 XORed in), resulting in a cumulative bit swizzling
|
|
* required by the CPU of XORing in bit 6, 9, 10, and potentially 11, in order
|
|
* to match what the GPU expects.
|
|
*/
|
|
|
|
/**
|
|
* i915_gem_detect_bit_6_swizzle - detect bit 6 swizzling pattern
|
|
* @dev: DRM device
|
|
*
|
|
* Detects bit 6 swizzling of address lookup between IGD access and CPU
|
|
* access through main memory.
|
|
*/
|
|
void
|
|
i915_gem_detect_bit_6_swizzle(struct drm_device *dev)
|
|
{
|
|
struct drm_i915_private *dev_priv = dev->dev_private;
|
|
uint32_t swizzle_x = I915_BIT_6_SWIZZLE_UNKNOWN;
|
|
uint32_t swizzle_y = I915_BIT_6_SWIZZLE_UNKNOWN;
|
|
|
|
if (INTEL_INFO(dev)->gen >= 8 || IS_VALLEYVIEW(dev)) {
|
|
/*
|
|
* On BDW+, swizzling is not used. We leave the CPU memory
|
|
* controller in charge of optimizing memory accesses without
|
|
* the extra address manipulation GPU side.
|
|
*
|
|
* VLV and CHV don't have GPU swizzling.
|
|
*/
|
|
swizzle_x = I915_BIT_6_SWIZZLE_NONE;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_NONE;
|
|
} else if (INTEL_INFO(dev)->gen >= 6) {
|
|
if (dev_priv->preserve_bios_swizzle) {
|
|
if (I915_READ(DISP_ARB_CTL) &
|
|
DISP_TILE_SURFACE_SWIZZLING) {
|
|
swizzle_x = I915_BIT_6_SWIZZLE_9_10;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_9;
|
|
} else {
|
|
swizzle_x = I915_BIT_6_SWIZZLE_NONE;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_NONE;
|
|
}
|
|
} else {
|
|
uint32_t dimm_c0, dimm_c1;
|
|
dimm_c0 = I915_READ(MAD_DIMM_C0);
|
|
dimm_c1 = I915_READ(MAD_DIMM_C1);
|
|
dimm_c0 &= MAD_DIMM_A_SIZE_MASK | MAD_DIMM_B_SIZE_MASK;
|
|
dimm_c1 &= MAD_DIMM_A_SIZE_MASK | MAD_DIMM_B_SIZE_MASK;
|
|
/* Enable swizzling when the channels are populated
|
|
* with identically sized dimms. We don't need to check
|
|
* the 3rd channel because no cpu with gpu attached
|
|
* ships in that configuration. Also, swizzling only
|
|
* makes sense for 2 channels anyway. */
|
|
if (dimm_c0 == dimm_c1) {
|
|
swizzle_x = I915_BIT_6_SWIZZLE_9_10;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_9;
|
|
} else {
|
|
swizzle_x = I915_BIT_6_SWIZZLE_NONE;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_NONE;
|
|
}
|
|
}
|
|
} else if (IS_GEN5(dev)) {
|
|
/* On Ironlake whatever DRAM config, GPU always do
|
|
* same swizzling setup.
|
|
*/
|
|
swizzle_x = I915_BIT_6_SWIZZLE_9_10;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_9;
|
|
} else if (IS_GEN2(dev)) {
|
|
/* As far as we know, the 865 doesn't have these bit 6
|
|
* swizzling issues.
|
|
*/
|
|
swizzle_x = I915_BIT_6_SWIZZLE_NONE;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_NONE;
|
|
} else if (IS_MOBILE(dev) || (IS_GEN3(dev) && !IS_G33(dev))) {
|
|
uint32_t dcc;
|
|
|
|
/* On 9xx chipsets, channel interleave by the CPU is
|
|
* determined by DCC. For single-channel, neither the CPU
|
|
* nor the GPU do swizzling. For dual channel interleaved,
|
|
* the GPU's interleave is bit 9 and 10 for X tiled, and bit
|
|
* 9 for Y tiled. The CPU's interleave is independent, and
|
|
* can be based on either bit 11 (haven't seen this yet) or
|
|
* bit 17 (common).
|
|
*/
|
|
dcc = I915_READ(DCC);
|
|
switch (dcc & DCC_ADDRESSING_MODE_MASK) {
|
|
case DCC_ADDRESSING_MODE_SINGLE_CHANNEL:
|
|
case DCC_ADDRESSING_MODE_DUAL_CHANNEL_ASYMMETRIC:
|
|
swizzle_x = I915_BIT_6_SWIZZLE_NONE;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_NONE;
|
|
break;
|
|
case DCC_ADDRESSING_MODE_DUAL_CHANNEL_INTERLEAVED:
|
|
if (dcc & DCC_CHANNEL_XOR_DISABLE) {
|
|
/* This is the base swizzling by the GPU for
|
|
* tiled buffers.
|
|
*/
|
|
swizzle_x = I915_BIT_6_SWIZZLE_9_10;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_9;
|
|
} else if ((dcc & DCC_CHANNEL_XOR_BIT_17) == 0) {
|
|
/* Bit 11 swizzling by the CPU in addition. */
|
|
swizzle_x = I915_BIT_6_SWIZZLE_9_10_11;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_9_11;
|
|
} else {
|
|
/* Bit 17 swizzling by the CPU in addition. */
|
|
swizzle_x = I915_BIT_6_SWIZZLE_9_10_17;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_9_17;
|
|
}
|
|
break;
|
|
}
|
|
|
|
/* check for L-shaped memory aka modified enhanced addressing */
|
|
if (IS_GEN4(dev) &&
|
|
!(I915_READ(DCC2) & DCC2_MODIFIED_ENHANCED_DISABLE)) {
|
|
swizzle_x = I915_BIT_6_SWIZZLE_UNKNOWN;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_UNKNOWN;
|
|
}
|
|
|
|
if (dcc == 0xffffffff) {
|
|
DRM_ERROR("Couldn't read from MCHBAR. "
|
|
"Disabling tiling.\n");
|
|
swizzle_x = I915_BIT_6_SWIZZLE_UNKNOWN;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_UNKNOWN;
|
|
}
|
|
} else {
|
|
/* The 965, G33, and newer, have a very flexible memory
|
|
* configuration. It will enable dual-channel mode
|
|
* (interleaving) on as much memory as it can, and the GPU
|
|
* will additionally sometimes enable different bit 6
|
|
* swizzling for tiled objects from the CPU.
|
|
*
|
|
* Here's what I found on the G965:
|
|
* slot fill memory size swizzling
|
|
* 0A 0B 1A 1B 1-ch 2-ch
|
|
* 512 0 0 0 512 0 O
|
|
* 512 0 512 0 16 1008 X
|
|
* 512 0 0 512 16 1008 X
|
|
* 0 512 0 512 16 1008 X
|
|
* 1024 1024 1024 0 2048 1024 O
|
|
*
|
|
* We could probably detect this based on either the DRB
|
|
* matching, which was the case for the swizzling required in
|
|
* the table above, or from the 1-ch value being less than
|
|
* the minimum size of a rank.
|
|
*
|
|
* Reports indicate that the swizzling actually
|
|
* varies depending upon page placement inside the
|
|
* channels, i.e. we see swizzled pages where the
|
|
* banks of memory are paired and unswizzled on the
|
|
* uneven portion, so leave that as unknown.
|
|
*/
|
|
if (I915_READ16(C0DRB3) == I915_READ16(C1DRB3)) {
|
|
swizzle_x = I915_BIT_6_SWIZZLE_9_10;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_9;
|
|
}
|
|
}
|
|
|
|
if (swizzle_x == I915_BIT_6_SWIZZLE_UNKNOWN ||
|
|
swizzle_y == I915_BIT_6_SWIZZLE_UNKNOWN) {
|
|
/* Userspace likes to explode if it sees unknown swizzling,
|
|
* so lie. We will finish the lie when reporting through
|
|
* the get-tiling-ioctl by reporting the physical swizzle
|
|
* mode as unknown instead.
|
|
*
|
|
* As we don't strictly know what the swizzling is, it may be
|
|
* bit17 dependent, and so we need to also prevent the pages
|
|
* from being moved.
|
|
*/
|
|
dev_priv->quirks |= QUIRK_PIN_SWIZZLED_PAGES;
|
|
swizzle_x = I915_BIT_6_SWIZZLE_NONE;
|
|
swizzle_y = I915_BIT_6_SWIZZLE_NONE;
|
|
}
|
|
|
|
dev_priv->mm.bit_6_swizzle_x = swizzle_x;
|
|
dev_priv->mm.bit_6_swizzle_y = swizzle_y;
|
|
}
|
|
|
|
/*
|
|
* Swap every 64 bytes of this page around, to account for it having a new
|
|
* bit 17 of its physical address and therefore being interpreted differently
|
|
* by the GPU.
|
|
*/
|
|
static void
|
|
i915_gem_swizzle_page(struct page *page)
|
|
{
|
|
char temp[64];
|
|
char *vaddr;
|
|
int i;
|
|
|
|
vaddr = kmap(page);
|
|
|
|
for (i = 0; i < PAGE_SIZE; i += 128) {
|
|
memcpy(temp, &vaddr[i], 64);
|
|
memcpy(&vaddr[i], &vaddr[i + 64], 64);
|
|
memcpy(&vaddr[i + 64], temp, 64);
|
|
}
|
|
|
|
kunmap(page);
|
|
}
|
|
|
|
/**
|
|
* i915_gem_object_do_bit_17_swizzle - fixup bit 17 swizzling
|
|
* @obj: i915 GEM buffer object
|
|
*
|
|
* This function fixes up the swizzling in case any page frame number for this
|
|
* object has changed in bit 17 since that state has been saved with
|
|
* i915_gem_object_save_bit_17_swizzle().
|
|
*
|
|
* This is called when pinning backing storage again, since the kernel is free
|
|
* to move unpinned backing storage around (either by directly moving pages or
|
|
* by swapping them out and back in again).
|
|
*/
|
|
void
|
|
i915_gem_object_do_bit_17_swizzle(struct drm_i915_gem_object *obj)
|
|
{
|
|
struct sg_page_iter sg_iter;
|
|
int i;
|
|
|
|
if (obj->bit_17 == NULL)
|
|
return;
|
|
|
|
i = 0;
|
|
for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, 0) {
|
|
struct page *page = sg_page_iter_page(&sg_iter);
|
|
char new_bit_17 = page_to_phys(page) >> 17;
|
|
if ((new_bit_17 & 0x1) !=
|
|
(test_bit(i, obj->bit_17) != 0)) {
|
|
i915_gem_swizzle_page(page);
|
|
set_page_dirty(page);
|
|
}
|
|
i++;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* i915_gem_object_save_bit_17_swizzle - save bit 17 swizzling
|
|
* @obj: i915 GEM buffer object
|
|
*
|
|
* This function saves the bit 17 of each page frame number so that swizzling
|
|
* can be fixed up later on with i915_gem_object_do_bit_17_swizzle(). This must
|
|
* be called before the backing storage can be unpinned.
|
|
*/
|
|
void
|
|
i915_gem_object_save_bit_17_swizzle(struct drm_i915_gem_object *obj)
|
|
{
|
|
struct sg_page_iter sg_iter;
|
|
int page_count = obj->base.size >> PAGE_SHIFT;
|
|
int i;
|
|
|
|
if (obj->bit_17 == NULL) {
|
|
obj->bit_17 = kcalloc(BITS_TO_LONGS(page_count),
|
|
sizeof(long), GFP_KERNEL);
|
|
if (obj->bit_17 == NULL) {
|
|
DRM_ERROR("Failed to allocate memory for bit 17 "
|
|
"record\n");
|
|
return;
|
|
}
|
|
}
|
|
|
|
i = 0;
|
|
for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, 0) {
|
|
if (page_to_phys(sg_page_iter_page(&sg_iter)) & (1 << 17))
|
|
__set_bit(i, obj->bit_17);
|
|
else
|
|
__clear_bit(i, obj->bit_17);
|
|
i++;
|
|
}
|
|
}
|