tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: MIT
2/*
3 * Copyright © 2024 Intel Corporation
4 */
5
6#include <linux/cleanup.h>
7#include <drm/drm_managed.h>
8
9#include "xe_assert.h"
10#include "xe_bo.h"
11#include "xe_gt_printk.h"
12#include "xe_guc.h"
13#include "xe_guc_buf.h"
14#include "xe_sa.h"
15
16static struct xe_guc *cache_to_guc(struct xe_guc_buf_cache *cache)
17{
18 return container_of(cache, struct xe_guc, buf);
19}
20
21static struct xe_gt *cache_to_gt(struct xe_guc_buf_cache *cache)
22{
23 return guc_to_gt(cache_to_guc(cache));
24}
25
26/**
27 * xe_guc_buf_cache_init() - Initialize the GuC Buffer Cache.
28 * @cache: the &xe_guc_buf_cache to initialize
29 *
30 * The Buffer Cache allows to obtain a reusable buffer that can be used to pass
31 * indirect H2G data to GuC without a need to create a ad-hoc allocation.
32 *
33 * Return: 0 on success or a negative error code on failure.
34 */
35int xe_guc_buf_cache_init(struct xe_guc_buf_cache *cache)
36{
37 struct xe_gt *gt = cache_to_gt(cache);
38 struct xe_sa_manager *sam;
39
40 /* XXX: currently it's useful only for the PF actions */
41 if (!IS_SRIOV_PF(gt_to_xe(gt)))
42 return 0;
43
44 sam = __xe_sa_bo_manager_init(gt_to_tile(gt), SZ_8K, 0, sizeof(u32));
45 if (IS_ERR(sam))
46 return PTR_ERR(sam);
47 cache->sam = sam;
48
49 xe_gt_dbg(gt, "reusable buffer with %u dwords at %#x for %ps\n",
50 xe_guc_buf_cache_dwords(cache), xe_bo_ggtt_addr(sam->bo),
51 __builtin_return_address(0));
52 return 0;
53}
54
55/**
56 * xe_guc_buf_cache_dwords() - Number of dwords the GuC Buffer Cache supports.
57 * @cache: the &xe_guc_buf_cache to query
58 *
59 * Return: a size of the largest reusable buffer (in dwords)
60 */
61u32 xe_guc_buf_cache_dwords(struct xe_guc_buf_cache *cache)
62{
63 return cache->sam ? cache->sam->base.size / sizeof(u32) : 0;
64}
65
66/**
67 * xe_guc_buf_reserve() - Reserve a new sub-allocation.
68 * @cache: the &xe_guc_buf_cache where reserve sub-allocation
69 * @dwords: the requested size of the buffer in dwords
70 *
71 * Use xe_guc_buf_is_valid() to check if returned buffer reference is valid.
72 * Must use xe_guc_buf_release() to release a sub-allocation.
73 *
74 * Return: a &xe_guc_buf of new sub-allocation.
75 */
76struct xe_guc_buf xe_guc_buf_reserve(struct xe_guc_buf_cache *cache, u32 dwords)
77{
78 struct drm_suballoc *sa;
79
80 if (cache->sam)
81 sa = __xe_sa_bo_new(cache->sam, dwords * sizeof(u32), GFP_ATOMIC);
82 else
83 sa = ERR_PTR(-EOPNOTSUPP);
84
85 return (struct xe_guc_buf){ .sa = sa };
86}
87
88/**
89 * xe_guc_buf_from_data() - Reserve a new sub-allocation using data.
90 * @cache: the &xe_guc_buf_cache where reserve sub-allocation
91 * @data: the data to flush the sub-allocation
92 * @size: the size of the data
93 *
94 * Similar to xe_guc_buf_reserve() but flushes @data to the GPU memory.
95 *
96 * Return: a &xe_guc_buf of new sub-allocation.
97 */
98struct xe_guc_buf xe_guc_buf_from_data(struct xe_guc_buf_cache *cache,
99 const void *data, size_t size)
100{
101 struct drm_suballoc *sa;
102
103 sa = __xe_sa_bo_new(cache->sam, size, GFP_ATOMIC);
104 if (!IS_ERR(sa))
105 memcpy(xe_sa_bo_cpu_addr(sa), data, size);
106
107 return (struct xe_guc_buf){ .sa = sa };
108}
109
110/**
111 * xe_guc_buf_release() - Release a sub-allocation.
112 * @buf: the &xe_guc_buf to release
113 *
114 * Releases a sub-allocation reserved by the xe_guc_buf_reserve().
115 */
116void xe_guc_buf_release(const struct xe_guc_buf buf)
117{
118 if (xe_guc_buf_is_valid(buf))
119 xe_sa_bo_free(buf.sa, NULL);
120}
121
122/**
123 * xe_guc_buf_flush() - Copy the data from the sub-allocation to the GPU memory.
124 * @buf: the &xe_guc_buf to flush
125 *
126 * Return: a GPU address of the sub-allocation.
127 */
128u64 xe_guc_buf_flush(const struct xe_guc_buf buf)
129{
130 xe_sa_bo_flush_write(buf.sa);
131 return xe_sa_bo_gpu_addr(buf.sa);
132}
133
134/**
135 * xe_guc_buf_cpu_ptr() - Obtain a CPU pointer to the sub-allocation.
136 * @buf: the &xe_guc_buf to query
137 *
138 * Return: a CPU pointer of the sub-allocation.
139 */
140void *xe_guc_buf_cpu_ptr(const struct xe_guc_buf buf)
141{
142 return xe_sa_bo_cpu_addr(buf.sa);
143}
144
145/**
146 * xe_guc_buf_gpu_addr() - Obtain a GPU address of the sub-allocation.
147 * @buf: the &xe_guc_buf to query
148 *
149 * Return: a GPU address of the sub-allocation.
150 */
151u64 xe_guc_buf_gpu_addr(const struct xe_guc_buf buf)
152{
153 return xe_sa_bo_gpu_addr(buf.sa);
154}
155
156/**
157 * xe_guc_cache_gpu_addr_from_ptr() - Lookup a GPU address using the pointer.
158 * @cache: the &xe_guc_buf_cache with sub-allocations
159 * @ptr: the CPU pointer of the sub-allocation
160 * @size: the size of the data
161 *
162 * Return: a GPU address on success or 0 if the pointer was unrelated.
163 */
164u64 xe_guc_cache_gpu_addr_from_ptr(struct xe_guc_buf_cache *cache, const void *ptr, u32 size)
165{
166 ptrdiff_t offset = ptr - cache->sam->cpu_ptr;
167
168 if (offset < 0 || offset + size > cache->sam->base.size)
169 return 0;
170
171 return cache->sam->gpu_addr + offset;
172}
173
174#if IS_BUILTIN(CONFIG_DRM_XE_KUNIT_TEST)
175#include "tests/xe_guc_buf_kunit.c"
176#endif