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 * @pdata: afu platform device's pdata.
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 */
50int afu_mmio_region_add(struct dfl_feature_platform_data *pdata,
51			u32 region_index, u64 region_size, u64 phys, u32 flags)
52{
53	struct dfl_afu_mmio_region *region;
54	struct dfl_afu *afu;
55	int ret = 0;
56
57	region = devm_kzalloc(&pdata->dev->dev, sizeof(*region), GFP_KERNEL);
58	if (!region)
59		return -ENOMEM;
60
61	region->index = region_index;
62	region->size = region_size;
63	region->phys = phys;
64	region->flags = flags;
65
66	mutex_lock(&pdata->lock);
67
68	afu = dfl_fpga_pdata_get_private(pdata);
69
70	/* check if @index already exists */
71	if (get_region_by_index(afu, region_index)) {
72		mutex_unlock(&pdata->lock);
73		ret = -EEXIST;
74		goto exit;
75	}
76
77	region_size = PAGE_ALIGN(region_size);
78	region->offset = afu->region_cur_offset;
79	list_add(&region->node, &afu->regions);
80
81	afu->region_cur_offset += region_size;
82	afu->num_regions++;
83	mutex_unlock(&pdata->lock);
84
85	return 0;
86
87exit:
88	devm_kfree(&pdata->dev->dev, region);
89	return ret;
90}
91
92/**
93 * afu_mmio_region_destroy - destroy all mmio regions under given feature dev.
94 * @pdata: afu platform device's pdata.
95 */
96void afu_mmio_region_destroy(struct dfl_feature_platform_data *pdata)
97{
98	struct dfl_afu *afu = dfl_fpga_pdata_get_private(pdata);
99	struct dfl_afu_mmio_region *tmp, *region;
100
101	list_for_each_entry_safe(region, tmp, &afu->regions, node)
102		devm_kfree(&pdata->dev->dev, region);
103}
104
105/**
106 * afu_mmio_region_get_by_index - find an afu region by index.
107 * @pdata: afu platform device's pdata.
108 * @region_index: region index.
109 * @pregion: ptr to region for result.
110 *
111 * Return: 0 on success, negative error code otherwise.
112 */
113int afu_mmio_region_get_by_index(struct dfl_feature_platform_data *pdata,
114				 u32 region_index,
115				 struct dfl_afu_mmio_region *pregion)
116{
117	struct dfl_afu_mmio_region *region;
118	struct dfl_afu *afu;
119	int ret = 0;
120
121	mutex_lock(&pdata->lock);
122	afu = dfl_fpga_pdata_get_private(pdata);
123	region = get_region_by_index(afu, region_index);
124	if (!region) {
125		ret = -EINVAL;
126		goto exit;
127	}
128	*pregion = *region;
129exit:
130	mutex_unlock(&pdata->lock);
131	return ret;
132}
133
134/**
135 * afu_mmio_region_get_by_offset - find an afu mmio region by offset and size
136 *
137 * @pdata: afu platform device's pdata.
138 * @offset: region offset from start of the device fd.
139 * @size: region size.
140 * @pregion: ptr to region for result.
141 *
142 * Find the region which fully contains the region described by input
143 * parameters (offset and size) from the feature dev's region linked list.
144 *
145 * Return: 0 on success, negative error code otherwise.
146 */
147int afu_mmio_region_get_by_offset(struct dfl_feature_platform_data *pdata,
148				  u64 offset, u64 size,
149				  struct dfl_afu_mmio_region *pregion)
150{
151	struct dfl_afu_mmio_region *region;
152	struct dfl_afu *afu;
153	int ret = 0;
154
155	mutex_lock(&pdata->lock);
156	afu = dfl_fpga_pdata_get_private(pdata);
157	for_each_region(region, afu)
158		if (region->offset <= offset &&
159		    region->offset + region->size >= offset + size) {
160			*pregion = *region;
161			goto exit;
162		}
163	ret = -EINVAL;
164exit:
165	mutex_unlock(&pdata->lock);
166	return ret;
167}
168