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