linux/linux-5.4.31/drivers/fpga/dfl-afu-region.c

167 lines
4.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Driver for FPGA Accelerated Function Unit (AFU) MMIO Region Management
*
* Copyright (C) 2017-2018 Intel Corporation, Inc.
*
* Authors:
* Wu Hao <hao.wu@intel.com>
* Xiao Guangrong <guangrong.xiao@linux.intel.com>
*/
#include "dfl-afu.h"
/**
* afu_mmio_region_init - init function for afu mmio region support
* @pdata: afu platform device's pdata.
*/
void afu_mmio_region_init(struct dfl_feature_platform_data *pdata)
{
struct dfl_afu *afu = dfl_fpga_pdata_get_private(pdata);
INIT_LIST_HEAD(&afu->regions);
}
#define for_each_region(region, afu) \
list_for_each_entry((region), &(afu)->regions, node)
static struct dfl_afu_mmio_region *get_region_by_index(struct dfl_afu *afu,
u32 region_index)
{
struct dfl_afu_mmio_region *region;
for_each_region(region, afu)
if (region->index == region_index)
return region;
return NULL;
}
/**
* afu_mmio_region_add - add a mmio region to given feature dev.
*
* @region_index: region index.
* @region_size: region size.
* @phys: region's physical address of this region.
* @flags: region flags (access permission).
*
* Return: 0 on success, negative error code otherwise.
*/
int afu_mmio_region_add(struct dfl_feature_platform_data *pdata,
u32 region_index, u64 region_size, u64 phys, u32 flags)
{
struct dfl_afu_mmio_region *region;
struct dfl_afu *afu;
int ret = 0;
region = devm_kzalloc(&pdata->dev->dev, sizeof(*region), GFP_KERNEL);
if (!region)
return -ENOMEM;
region->index = region_index;
region->size = region_size;
region->phys = phys;
region->flags = flags;
mutex_lock(&pdata->lock);
afu = dfl_fpga_pdata_get_private(pdata);
/* check if @index already exists */
if (get_region_by_index(afu, region_index)) {
mutex_unlock(&pdata->lock);
ret = -EEXIST;
goto exit;
}
region_size = PAGE_ALIGN(region_size);
region->offset = afu->region_cur_offset;
list_add(&region->node, &afu->regions);
afu->region_cur_offset += region_size;
afu->num_regions++;
mutex_unlock(&pdata->lock);
return 0;
exit:
devm_kfree(&pdata->dev->dev, region);
return ret;
}
/**
* afu_mmio_region_destroy - destroy all mmio regions under given feature dev.
* @pdata: afu platform device's pdata.
*/
void afu_mmio_region_destroy(struct dfl_feature_platform_data *pdata)
{
struct dfl_afu *afu = dfl_fpga_pdata_get_private(pdata);
struct dfl_afu_mmio_region *tmp, *region;
list_for_each_entry_safe(region, tmp, &afu->regions, node)
devm_kfree(&pdata->dev->dev, region);
}
/**
* afu_mmio_region_get_by_index - find an afu region by index.
* @pdata: afu platform device's pdata.
* @region_index: region index.
* @pregion: ptr to region for result.
*
* Return: 0 on success, negative error code otherwise.
*/
int afu_mmio_region_get_by_index(struct dfl_feature_platform_data *pdata,
u32 region_index,
struct dfl_afu_mmio_region *pregion)
{
struct dfl_afu_mmio_region *region;
struct dfl_afu *afu;
int ret = 0;
mutex_lock(&pdata->lock);
afu = dfl_fpga_pdata_get_private(pdata);
region = get_region_by_index(afu, region_index);
if (!region) {
ret = -EINVAL;
goto exit;
}
*pregion = *region;
exit:
mutex_unlock(&pdata->lock);
return ret;
}
/**
* afu_mmio_region_get_by_offset - find an afu mmio region by offset and size
*
* @pdata: afu platform device's pdata.
* @offset: region offset from start of the device fd.
* @size: region size.
* @pregion: ptr to region for result.
*
* Find the region which fully contains the region described by input
* parameters (offset and size) from the feature dev's region linked list.
*
* Return: 0 on success, negative error code otherwise.
*/
int afu_mmio_region_get_by_offset(struct dfl_feature_platform_data *pdata,
u64 offset, u64 size,
struct dfl_afu_mmio_region *pregion)
{
struct dfl_afu_mmio_region *region;
struct dfl_afu *afu;
int ret = 0;
mutex_lock(&pdata->lock);
afu = dfl_fpga_pdata_get_private(pdata);
for_each_region(region, afu)
if (region->offset <= offset &&
region->offset + region->size >= offset + size) {
*pregion = *region;
goto exit;
}
ret = -EINVAL;
exit:
mutex_unlock(&pdata->lock);
return ret;
}