1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Driver for FPGA Accelerated Function Unit (AFU) MMIO Region Management
4 *
5 * Copyright (C) 2017-2018 Intel Corporation, Inc.
6 *
7 * Authors:
8 * Wu Hao <[email protected]>
9 * Xiao Guangrong <[email protected]>
10 */
11 #include "dfl-afu.h"
12
13 /**
14 * afu_mmio_region_init - init function for afu mmio region support
15 * @fdata: afu feature dev data
16 */
afu_mmio_region_init(struct dfl_feature_dev_data * fdata)17 void afu_mmio_region_init(struct dfl_feature_dev_data *fdata)
18 {
19 struct dfl_afu *afu = dfl_fpga_fdata_get_private(fdata);
20
21 INIT_LIST_HEAD(&afu->regions);
22 }
23
24 #define for_each_region(region, afu) \
25 list_for_each_entry((region), &(afu)->regions, node)
26
get_region_by_index(struct dfl_afu * afu,u32 region_index)27 static struct dfl_afu_mmio_region *get_region_by_index(struct dfl_afu *afu,
28 u32 region_index)
29 {
30 struct dfl_afu_mmio_region *region;
31
32 for_each_region(region, afu)
33 if (region->index == region_index)
34 return region;
35
36 return NULL;
37 }
38
39 /**
40 * afu_mmio_region_add - add a mmio region to given feature dev.
41 *
42 * @fdata: afu feature dev data
43 * @region_index: region index.
44 * @region_size: region size.
45 * @phys: region's physical address of this region.
46 * @flags: region flags (access permission).
47 *
48 * Return: 0 on success, negative error code otherwise.
49 */
afu_mmio_region_add(struct dfl_feature_dev_data * fdata,u32 region_index,u64 region_size,u64 phys,u32 flags)50 int afu_mmio_region_add(struct dfl_feature_dev_data *fdata,
51 u32 region_index, u64 region_size, u64 phys, u32 flags)
52 {
53 struct device *dev = &fdata->dev->dev;
54 struct dfl_afu_mmio_region *region;
55 struct dfl_afu *afu;
56 int ret = 0;
57
58 region = devm_kzalloc(dev, sizeof(*region), GFP_KERNEL);
59 if (!region)
60 return -ENOMEM;
61
62 region->index = region_index;
63 region->size = region_size;
64 region->phys = phys;
65 region->flags = flags;
66
67 mutex_lock(&fdata->lock);
68
69 afu = dfl_fpga_fdata_get_private(fdata);
70
71 /* check if @index already exists */
72 if (get_region_by_index(afu, region_index)) {
73 mutex_unlock(&fdata->lock);
74 ret = -EEXIST;
75 goto exit;
76 }
77
78 region_size = PAGE_ALIGN(region_size);
79 region->offset = afu->region_cur_offset;
80 list_add(®ion->node, &afu->regions);
81
82 afu->region_cur_offset += region_size;
83 afu->num_regions++;
84 mutex_unlock(&fdata->lock);
85
86 return 0;
87
88 exit:
89 devm_kfree(dev, region);
90 return ret;
91 }
92
93 /**
94 * afu_mmio_region_destroy - destroy all mmio regions under given feature dev.
95 * @fdata: afu feature dev data
96 */
afu_mmio_region_destroy(struct dfl_feature_dev_data * fdata)97 void afu_mmio_region_destroy(struct dfl_feature_dev_data *fdata)
98 {
99 struct dfl_afu *afu = dfl_fpga_fdata_get_private(fdata);
100 struct dfl_afu_mmio_region *tmp, *region;
101
102 list_for_each_entry_safe(region, tmp, &afu->regions, node)
103 devm_kfree(&fdata->dev->dev, region);
104 }
105
106 /**
107 * afu_mmio_region_get_by_index - find an afu region by index.
108 * @fdata: afu feature dev data
109 * @region_index: region index.
110 * @pregion: ptr to region for result.
111 *
112 * Return: 0 on success, negative error code otherwise.
113 */
afu_mmio_region_get_by_index(struct dfl_feature_dev_data * fdata,u32 region_index,struct dfl_afu_mmio_region * pregion)114 int afu_mmio_region_get_by_index(struct dfl_feature_dev_data *fdata,
115 u32 region_index,
116 struct dfl_afu_mmio_region *pregion)
117 {
118 struct dfl_afu_mmio_region *region;
119 struct dfl_afu *afu;
120 int ret = 0;
121
122 mutex_lock(&fdata->lock);
123 afu = dfl_fpga_fdata_get_private(fdata);
124 region = get_region_by_index(afu, region_index);
125 if (!region) {
126 ret = -EINVAL;
127 goto exit;
128 }
129 *pregion = *region;
130 exit:
131 mutex_unlock(&fdata->lock);
132 return ret;
133 }
134
135 /**
136 * afu_mmio_region_get_by_offset - find an afu mmio region by offset and size
137 *
138 * @fdata: afu feature dev data
139 * @offset: region offset from start of the device fd.
140 * @size: region size.
141 * @pregion: ptr to region for result.
142 *
143 * Find the region which fully contains the region described by input
144 * parameters (offset and size) from the feature dev's region linked list.
145 *
146 * Return: 0 on success, negative error code otherwise.
147 */
afu_mmio_region_get_by_offset(struct dfl_feature_dev_data * fdata,u64 offset,u64 size,struct dfl_afu_mmio_region * pregion)148 int afu_mmio_region_get_by_offset(struct dfl_feature_dev_data *fdata,
149 u64 offset, u64 size,
150 struct dfl_afu_mmio_region *pregion)
151 {
152 struct dfl_afu_mmio_region *region;
153 struct dfl_afu *afu;
154 int ret = 0;
155
156 mutex_lock(&fdata->lock);
157 afu = dfl_fpga_fdata_get_private(fdata);
158 for_each_region(region, afu)
159 if (region->offset <= offset &&
160 region->offset + region->size >= offset + size) {
161 *pregion = *region;
162 goto exit;
163 }
164 ret = -EINVAL;
165 exit:
166 mutex_unlock(&fdata->lock);
167 return ret;
168 }
169