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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/gpu/drm/i915/i915_scatterlist.h | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/drm/i915/i915_scatterlist.h')
-rw-r--r-- | drivers/gpu/drm/i915/i915_scatterlist.h | 231 |
1 files changed, 231 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_scatterlist.h b/drivers/gpu/drm/i915/i915_scatterlist.h new file mode 100644 index 000000000..b0a1db44f --- /dev/null +++ b/drivers/gpu/drm/i915/i915_scatterlist.h @@ -0,0 +1,231 @@ +/* + * SPDX-License-Identifier: MIT + * + * Copyright © 2016 Intel Corporation + */ + +#ifndef I915_SCATTERLIST_H +#define I915_SCATTERLIST_H + +#include <linux/pfn.h> +#include <linux/scatterlist.h> +#include <linux/dma-mapping.h> +#include <xen/xen.h> + +#include "i915_gem.h" + +struct drm_mm_node; +struct ttm_resource; + +/* + * Optimised SGL iterator for GEM objects + */ +static __always_inline struct sgt_iter { + struct scatterlist *sgp; + union { + unsigned long pfn; + dma_addr_t dma; + }; + unsigned int curr; + unsigned int max; +} __sgt_iter(struct scatterlist *sgl, bool dma) { + struct sgt_iter s = { .sgp = sgl }; + + if (dma && s.sgp && sg_dma_len(s.sgp) == 0) { + s.sgp = NULL; + } else if (s.sgp) { + s.max = s.curr = s.sgp->offset; + if (dma) { + s.dma = sg_dma_address(s.sgp); + s.max += sg_dma_len(s.sgp); + } else { + s.pfn = page_to_pfn(sg_page(s.sgp)); + s.max += s.sgp->length; + } + } + + return s; +} + +static inline int __sg_page_count(const struct scatterlist *sg) +{ + return sg->length >> PAGE_SHIFT; +} + +static inline int __sg_dma_page_count(const struct scatterlist *sg) +{ + return sg_dma_len(sg) >> PAGE_SHIFT; +} + +static inline struct scatterlist *____sg_next(struct scatterlist *sg) +{ + ++sg; + if (unlikely(sg_is_chain(sg))) + sg = sg_chain_ptr(sg); + return sg; +} + +/** + * __sg_next - return the next scatterlist entry in a list + * @sg: The current sg entry + * + * Description: + * If the entry is the last, return NULL; otherwise, step to the next + * element in the array (@sg@+1). If that's a chain pointer, follow it; + * otherwise just return the pointer to the current element. + **/ +static inline struct scatterlist *__sg_next(struct scatterlist *sg) +{ + return sg_is_last(sg) ? NULL : ____sg_next(sg); +} + +/** + * __for_each_sgt_daddr - iterate over the device addresses of the given sg_table + * @__dp: Device address (output) + * @__iter: 'struct sgt_iter' (iterator state, internal) + * @__sgt: sg_table to iterate over (input) + * @__step: step size + */ +#define __for_each_sgt_daddr(__dp, __iter, __sgt, __step) \ + for ((__iter) = __sgt_iter((__sgt)->sgl, true); \ + ((__dp) = (__iter).dma + (__iter).curr), (__iter).sgp; \ + (((__iter).curr += (__step)) >= (__iter).max) ? \ + (__iter) = __sgt_iter(__sg_next((__iter).sgp), true), 0 : 0) + +/** + * for_each_sgt_page - iterate over the pages of the given sg_table + * @__pp: page pointer (output) + * @__iter: 'struct sgt_iter' (iterator state, internal) + * @__sgt: sg_table to iterate over (input) + */ +#define for_each_sgt_page(__pp, __iter, __sgt) \ + for ((__iter) = __sgt_iter((__sgt)->sgl, false); \ + ((__pp) = (__iter).pfn == 0 ? NULL : \ + pfn_to_page((__iter).pfn + ((__iter).curr >> PAGE_SHIFT))); \ + (((__iter).curr += PAGE_SIZE) >= (__iter).max) ? \ + (__iter) = __sgt_iter(__sg_next((__iter).sgp), false), 0 : 0) + +/** + * i915_sg_dma_sizes - Record the dma segment sizes of a scatterlist + * @sg: The scatterlist + * + * Return: An unsigned int with segment sizes logically or'ed together. + * A caller can use this information to determine what hardware page table + * entry sizes can be used to map the memory represented by the scatterlist. + */ +static inline unsigned int i915_sg_dma_sizes(struct scatterlist *sg) +{ + unsigned int page_sizes; + + page_sizes = 0; + while (sg && sg_dma_len(sg)) { + GEM_BUG_ON(sg->offset); + GEM_BUG_ON(!IS_ALIGNED(sg_dma_len(sg), PAGE_SIZE)); + page_sizes |= sg_dma_len(sg); + sg = __sg_next(sg); + } + + return page_sizes; +} + +static inline unsigned int i915_sg_segment_size(struct device *dev) +{ + size_t max = min_t(size_t, UINT_MAX, dma_max_mapping_size(dev)); + + /* + * For Xen PV guests pages aren't contiguous in DMA (machine) address + * space. The DMA API takes care of that both in dma_alloc_* (by + * calling into the hypervisor to make the pages contiguous) and in + * dma_map_* (by bounce buffering). But i915 abuses ignores the + * coherency aspects of the DMA API and thus can't cope with bounce + * buffering actually happening, so add a hack here to force small + * allocations and mappings when running in PV mode on Xen. + * + * Note this will still break if bounce buffering is required for other + * reasons, like confidential computing hypervisors or PCIe root ports + * with addressing limitations. + */ + if (xen_pv_domain()) + max = PAGE_SIZE; + return round_down(max, PAGE_SIZE); +} + +bool i915_sg_trim(struct sg_table *orig_st); + +/** + * struct i915_refct_sgt_ops - Operations structure for struct i915_refct_sgt + */ +struct i915_refct_sgt_ops { + /** + * release() - Free the memory of the struct i915_refct_sgt + * @ref: struct kref that is embedded in the struct i915_refct_sgt + */ + void (*release)(struct kref *ref); +}; + +/** + * struct i915_refct_sgt - A refcounted scatter-gather table + * @kref: struct kref for refcounting + * @table: struct sg_table holding the scatter-gather table itself. Note that + * @table->sgl = NULL can be used to determine whether a scatter-gather table + * is present or not. + * @size: The size in bytes of the underlying memory buffer + * @ops: The operations structure. + */ +struct i915_refct_sgt { + struct kref kref; + struct sg_table table; + size_t size; + const struct i915_refct_sgt_ops *ops; +}; + +/** + * i915_refct_sgt_put - Put a refcounted sg-table + * @rsgt the struct i915_refct_sgt to put. + */ +static inline void i915_refct_sgt_put(struct i915_refct_sgt *rsgt) +{ + if (rsgt) + kref_put(&rsgt->kref, rsgt->ops->release); +} + +/** + * i915_refct_sgt_get - Get a refcounted sg-table + * @rsgt the struct i915_refct_sgt to get. + */ +static inline struct i915_refct_sgt * +i915_refct_sgt_get(struct i915_refct_sgt *rsgt) +{ + kref_get(&rsgt->kref); + return rsgt; +} + +/** + * __i915_refct_sgt_init - Initialize a refcounted sg-list with a custom + * operations structure + * @rsgt The struct i915_refct_sgt to initialize. + * @size: Size in bytes of the underlying memory buffer. + * @ops: A customized operations structure in case the refcounted sg-list + * is embedded into another structure. + */ +static inline void __i915_refct_sgt_init(struct i915_refct_sgt *rsgt, + size_t size, + const struct i915_refct_sgt_ops *ops) +{ + kref_init(&rsgt->kref); + rsgt->table.sgl = NULL; + rsgt->size = size; + rsgt->ops = ops; +} + +void i915_refct_sgt_init(struct i915_refct_sgt *rsgt, size_t size); + +struct i915_refct_sgt *i915_rsgt_from_mm_node(const struct drm_mm_node *node, + u64 region_start, + u32 page_alignment); + +struct i915_refct_sgt *i915_rsgt_from_buddy_resource(struct ttm_resource *res, + u64 region_start, + u32 page_alignment); + +#endif |