/* * Copyright © 2008 Intel Corporation * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS * IN THE SOFTWARE. * * Authors: * Eric Anholt * */ #include #include #include #include #include "i915_drv.h" /** * DOC: buffer object tiling * * i915_gem_set_tiling() and i915_gem_get_tiling() is the userspace interface to * declare fence register requirements. * * In principle GEM doesn't care at all about the internal data layout of an * object, and hence it also doesn't care about tiling or swizzling. There's two * exceptions: * * - For X and Y tiling the hardware provides detilers for CPU access, so called * fences. Since there's only a limited amount of them the kernel must manage * these, and therefore userspace must tell the kernel the object tiling if it * wants to use fences for detiling. * - On gen3 and gen4 platforms have a swizzling pattern for tiled objects which * depends upon the physical page frame number. When swapping such objects the * page frame number might change and the kernel must be able to fix this up * and hence now the tiling. Note that on a subset of platforms with * asymmetric memory channel population the swizzling pattern changes in an * unknown way, and for those the kernel simply forbids swapping completely. * * Since neither of this applies for new tiling layouts on modern platforms like * W, Ys and Yf tiling GEM only allows object tiling to be set to X or Y tiled. * Anything else can be handled in userspace entirely without the kernel's * invovlement. */ /* 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 (IS_GEN2(dev) || (tiling_mode == I915_TILING_Y && HAS_128_BYTE_Y_TILING(dev))) tile_width = 128; else tile_width = 512; /* check maximum stride & object size */ /* i965+ stores the end address of the gtt mapping in the fence * reg, so dont bother to check the size */ if (INTEL_INFO(dev)->gen >= 7) { if (stride / 128 > GEN7_FENCE_MAX_PITCH_VAL) return false; } else if (INTEL_INFO(dev)->gen >= 4) { if (stride / 128 > I965_FENCE_MAX_PITCH_VAL) return false; } else { if (stride > 8192) return false; if (IS_GEN3(dev)) { if (size > I830_FENCE_MAX_SIZE_VAL << 20) return false; } else { if (size > I830_FENCE_MAX_SIZE_VAL << 19) return false; } } if (stride < tile_width) return false; /* 965+ just needs multiples of tile width */ if (INTEL_INFO(dev)->gen >= 4) { if (stride & (tile_width - 1)) return false; return true; } /* Pre-965 needs power of two tile widths */ if (stride & (stride - 1)) return false; return true; } /* Is the current GTT allocation valid for the change in tiling? */ static bool i915_gem_object_fence_ok(struct drm_i915_gem_object *obj, int tiling_mode) { u32 size; if (tiling_mode == I915_TILING_NONE) return true; if (INTEL_INFO(obj->base.dev)->gen >= 4) return true; if (INTEL_INFO(obj->base.dev)->gen == 3) { if (i915_gem_obj_ggtt_offset(obj) & ~I915_FENCE_START_MASK) return false; } else { if (i915_gem_obj_ggtt_offset(obj) & ~I830_FENCE_START_MASK) return false; } size = i915_gem_get_gtt_size(obj->base.dev, obj->base.size, tiling_mode); if (i915_gem_obj_ggtt_size(obj) != size) return false; if (i915_gem_obj_ggtt_offset(obj) & (size - 1)) return false; return true; } /** * i915_gem_set_tiling - IOCTL handler to set tiling mode * @dev: DRM device * @data: data pointer for the ioctl * @file: DRM file for the ioctl call * * Sets the tiling mode of an object, returning the required swizzling of * bit 6 of addresses in the object. * * Called by the user via ioctl. * * Returns: * Zero on success, negative errno on failure. */ int i915_gem_set_tiling(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_set_tiling *args = data; struct drm_i915_private *dev_priv = dev->dev_private; struct drm_i915_gem_object *obj; int ret = 0; obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle)); if (&obj->base == NULL) return -ENOENT; if (!i915_tiling_ok(dev, args->stride, obj->base.size, args->tiling_mode)) { drm_gem_object_unreference_unlocked(&obj->base); return -EINVAL; } mutex_lock(&dev->struct_mutex); if (obj->pin_display || obj->framebuffer_references) { ret = -EBUSY; goto err; } if (args->tiling_mode == I915_TILING_NONE) { args->swizzle_mode = I915_BIT_6_SWIZZLE_NONE; args->stride = 0; } else { if (args->tiling_mode == I915_TILING_X) args->swizzle_mode = dev_priv->mm.bit_6_swizzle_x; else args->swizzle_mode = dev_priv->mm.bit_6_swizzle_y; /* Hide bit 17 swizzling from the user. This prevents old Mesa * from aborting the application on sw fallbacks to bit 17, * and we use the pread/pwrite bit17 paths to swizzle for it. * If there was a user that was relying on the swizzle * information for drm_intel_bo_map()ed reads/writes this would * break it, but we don't have any of those. */ if (args->swizzle_mode == I915_BIT_6_SWIZZLE_9_17) args->swizzle_mode = I915_BIT_6_SWIZZLE_9; if (args->swizzle_mode == I915_BIT_6_SWIZZLE_9_10_17) args->swizzle_mode = I915_BIT_6_SWIZZLE_9_10; /* If we can't handle the swizzling, make it untiled. */ if (args->swizzle_mode == I915_BIT_6_SWIZZLE_UNKNOWN) { args->tiling_mode = I915_TILING_NONE; args->swizzle_mode = I915_BIT_6_SWIZZLE_NONE; args->stride = 0; } } if (args->tiling_mode != obj->tiling_mode || args->stride != obj->stride) { /* We need to rebind the object if its current allocation * no longer meets the alignment restrictions for its new * tiling mode. Otherwise we can just leave it alone, but * need to ensure that any fence register is updated before * the next fenced (either through the GTT or by the BLT unit * on older GPUs) access. * * After updating the tiling parameters, we then flag whether * we need to update an associated fence register. Note this * has to also include the unfenced register the GPU uses * whilst executing a fenced command for an untiled object. */ if (obj->map_and_fenceable && !i915_gem_object_fence_ok(obj, args->tiling_mode)) ret = i915_gem_object_ggtt_unbind(obj); if (ret == 0) { if (obj->pages && obj->madv == I915_MADV_WILLNEED && dev_priv->quirks & QUIRK_PIN_SWIZZLED_PAGES) { if (args->tiling_mode == I915_TILING_NONE) i915_gem_object_unpin_pages(obj); if (obj->tiling_mode == I915_TILING_NONE) i915_gem_object_pin_pages(obj); } obj->fence_dirty = obj->last_fenced_req || obj->fence_reg != I915_FENCE_REG_NONE; obj->tiling_mode = args->tiling_mode; obj->stride = args->stride; /* Force the fence to be reacquired for GTT access */ i915_gem_release_mmap(obj); } } /* we have to maintain this existing ABI... */ args->stride = obj->stride; args->tiling_mode = obj->tiling_mode; /* Try to preallocate memory required to save swizzling on put-pages */ if (i915_gem_object_needs_bit17_swizzle(obj)) { if (obj->bit_17 == NULL) { obj->bit_17 = kcalloc(BITS_TO_LONGS(obj->base.size >> PAGE_SHIFT), sizeof(long), GFP_KERNEL); } } else { kfree(obj->bit_17); obj->bit_17 = NULL; } err: drm_gem_object_unreference(&obj->base); mutex_unlock(&dev->struct_mutex); return ret; } /** * i915_gem_get_tiling - IOCTL handler to get tiling mode * @dev: DRM device * @data: data pointer for the ioctl * @file: DRM file for the ioctl call * * Returns the current tiling mode and required bit 6 swizzling for the object. * * Called by the user via ioctl. * * Returns: * Zero on success, negative errno on failure. */ int i915_gem_get_tiling(struct drm_device *dev, void *data, struct drm_file *file) { struct drm_i915_gem_get_tiling *args = data; struct drm_i915_private *dev_priv = dev->dev_private; struct drm_i915_gem_object *obj; obj = to_intel_bo(drm_gem_object_lookup(dev, file, args->handle)); if (&obj->base == NULL) return -ENOENT; mutex_lock(&dev->struct_mutex); args->tiling_mode = obj->tiling_mode; switch (obj->tiling_mode) { case I915_TILING_X: args->swizzle_mode = dev_priv->mm.bit_6_swizzle_x; break; case I915_TILING_Y: args->swizzle_mode = dev_priv->mm.bit_6_swizzle_y; break; case I915_TILING_NONE: args->swizzle_mode = I915_BIT_6_SWIZZLE_NONE; break; default: DRM_ERROR("unknown tiling mode\n"); } /* Hide bit 17 from the user -- see comment in i915_gem_set_tiling */ if (dev_priv->quirks & QUIRK_PIN_SWIZZLED_PAGES) args->phys_swizzle_mode = I915_BIT_6_SWIZZLE_UNKNOWN; else args->phys_swizzle_mode = args->swizzle_mode; if (args->swizzle_mode == I915_BIT_6_SWIZZLE_9_17) args->swizzle_mode = I915_BIT_6_SWIZZLE_9; if (args->swizzle_mode == I915_BIT_6_SWIZZLE_9_10_17) args->swizzle_mode = I915_BIT_6_SWIZZLE_9_10; drm_gem_object_unreference(&obj->base); mutex_unlock(&dev->struct_mutex); return 0; }