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 <hao.wu@intel.com>
9 * Xiao Guangrong <guangrong.xiao@linux.intel.com>
10 */
11#include "dfl-afu.h"
12
13/**
14 * afu_mmio_region_init - init function for afu mmio region support
15 * @pdata: afu platform device's pdata.
16 */
17void afu_mmio_region_init(struct dfl_feature_platform_data *pdata)
18{
19 struct dfl_afu *afu = dfl_fpga_pdata_get_private(pdata);
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
27static 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 * @region_index: region index.
43 * @region_size: region size.
44 * @phys: region's physical address of this region.
45 * @flags: region flags (access permission).
46 *
47 * Return: 0 on success, negative error code otherwise.
48 */
49int afu_mmio_region_add(struct dfl_feature_platform_data *pdata,
50 u32 region_index, u64 region_size, u64 phys, u32 flags)
51{
52 struct dfl_afu_mmio_region *region;
53 struct dfl_afu *afu;
54 int ret = 0;
55
56 region = devm_kzalloc(&pdata->dev->dev, sizeof(*region), GFP_KERNEL);
57 if (!region)
58 return -ENOMEM;
59
60 region->index = region_index;
61 region->size = region_size;
62 region->phys = phys;
63 region->flags = flags;
64
65 mutex_lock(&pdata->lock);
66
67 afu = dfl_fpga_pdata_get_private(pdata);
68
69 /* check if @index already exists */
70 if (get_region_by_index(afu, region_index)) {
71 mutex_unlock(&pdata->lock);
72 ret = -EEXIST;
73 goto exit;
74 }
75
76 region_size = PAGE_ALIGN(region_size);
77 region->offset = afu->region_cur_offset;
78 list_add(&region->node, &afu->regions);
79
80 afu->region_cur_offset += region_size;
81 afu->num_regions++;
82 mutex_unlock(&pdata->lock);
83
84 return 0;
85
86exit:
87 devm_kfree(&pdata->dev->dev, region);
88 return ret;
89}
90
91/**
92 * afu_mmio_region_destroy - destroy all mmio regions under given feature dev.
93 * @pdata: afu platform device's pdata.
94 */
95void afu_mmio_region_destroy(struct dfl_feature_platform_data *pdata)
96{
97 struct dfl_afu *afu = dfl_fpga_pdata_get_private(pdata);
98 struct dfl_afu_mmio_region *tmp, *region;
99
100 list_for_each_entry_safe(region, tmp, &afu->regions, node)
101 devm_kfree(&pdata->dev->dev, region);
102}
103
104/**
105 * afu_mmio_region_get_by_index - find an afu region by index.
106 * @pdata: afu platform device's pdata.
107 * @region_index: region index.
108 * @pregion: ptr to region for result.
109 *
110 * Return: 0 on success, negative error code otherwise.
111 */
112int afu_mmio_region_get_by_index(struct dfl_feature_platform_data *pdata,
113 u32 region_index,
114 struct dfl_afu_mmio_region *pregion)
115{
116 struct dfl_afu_mmio_region *region;
117 struct dfl_afu *afu;
118 int ret = 0;
119
120 mutex_lock(&pdata->lock);
121 afu = dfl_fpga_pdata_get_private(pdata);
122 region = get_region_by_index(afu, region_index);
123 if (!region) {
124 ret = -EINVAL;
125 goto exit;
126 }
127 *pregion = *region;
128exit:
129 mutex_unlock(&pdata->lock);
130 return ret;
131}
132
133/**
134 * afu_mmio_region_get_by_offset - find an afu mmio region by offset and size
135 *
136 * @pdata: afu platform device's pdata.
137 * @offset: region offset from start of the device fd.
138 * @size: region size.
139 * @pregion: ptr to region for result.
140 *
141 * Find the region which fully contains the region described by input
142 * parameters (offset and size) from the feature dev's region linked list.
143 *
144 * Return: 0 on success, negative error code otherwise.
145 */
146int afu_mmio_region_get_by_offset(struct dfl_feature_platform_data *pdata,
147 u64 offset, u64 size,
148 struct dfl_afu_mmio_region *pregion)
149{
150 struct dfl_afu_mmio_region *region;
151 struct dfl_afu *afu;
152 int ret = 0;
153
154 mutex_lock(&pdata->lock);
155 afu = dfl_fpga_pdata_get_private(pdata);
156 for_each_region(region, afu)
157 if (region->offset <= offset &&
158 region->offset + region->size >= offset + size) {
159 *pregion = *region;
160 goto exit;
161 }
162 ret = -EINVAL;
163exit:
164 mutex_unlock(&pdata->lock);
165 return ret;
166}
167