dfl-afu-region.c

  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 * @fdata: afu feature dev data
 16 */
 17void 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
 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 * @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 */
 50int 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(&region->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
 88exit:
 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 */
 97void 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 */
114int 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;
130exit:
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 */
148int 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;
165exit:
166	mutex_unlock(&fdata->lock);
167	return ret;
168}