xref: /linux/drivers/fpga/dfl-afu-region.c (revision 9a87ffc99ec8eb8d35eed7c4f816d75f5cc9662e)
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  */
afu_mmio_region_init(struct dfl_feature_platform_data * pdata)17 void 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 
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  * @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  */
afu_mmio_region_add(struct dfl_feature_platform_data * pdata,u32 region_index,u64 region_size,u64 phys,u32 flags)50 int 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 
87 exit:
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  */
afu_mmio_region_destroy(struct dfl_feature_platform_data * pdata)96 void 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  */
afu_mmio_region_get_by_index(struct dfl_feature_platform_data * pdata,u32 region_index,struct dfl_afu_mmio_region * pregion)113 int 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;
129 exit:
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  */
afu_mmio_region_get_by_offset(struct dfl_feature_platform_data * pdata,u64 offset,u64 size,struct dfl_afu_mmio_region * pregion)147 int 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;
164 exit:
165 	mutex_unlock(&pdata->lock);
166 	return ret;
167 }
168