Files
bizhang_-obav/src/drivers/boards/common/board_dma_alloc.c
Daniel Agar ea3acb7121 cmake remove circular linking and reorganize
- px4_add_module now requires MAIN
 - px4_add_library doesn't automatically link
2018-04-29 21:48:54 -04:00

157 lines
5.1 KiB
C

/****************************************************************************
*
* Copyright (C) 2016 PX4 Development Team. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name PX4 nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/**
* @file board_dma_alloc.c
*
* Provide the board dma allocator interface.
*/
/************************************************************************************
* Included Files
************************************************************************************/
#include <px4_config.h>
#include "board_config.h"
#include <stdint.h>
#include <errno.h>
#include <nuttx/mm/gran.h>
#include <perf/perf_counter.h>
/************************************************************************************
* Definitions
************************************************************************************/
/************************************************************************************
* Private Functions
************************************************************************************/
/************************************************************************************
* Public Functions
************************************************************************************/
/************************************************************************************
* Name: board_dma_alloc_init
*
* Description:
* All boards may optionally provide this API to instantiate a pool of
* memory for uses with FAST FS DMA operations.
*
************************************************************************************/
#if defined(BOARD_DMA_ALLOC_POOL_SIZE)
# if !defined(CONFIG_GRAN) || !defined(CONFIG_FAT_DMAMEMORY)
# error microSD DMA support requires CONFIG_GRAN
# endif
static GRAN_HANDLE dma_allocator;
/*
* The DMA heap size constrains the total number of things that can be
* ready to do DMA at a time.
*
* For example, FAT DMA depends on one sector-sized buffer per filesystem plus
* one sector-sized buffer per file.
*
* We use a fundamental alignment / granule size of 64B; this is sufficient
* to guarantee alignment for the largest STM32 DMA burst (16 beats x 32bits).
*/
static uint8_t g_dma_heap[BOARD_DMA_ALLOC_POOL_SIZE] __attribute__((aligned(64)));
static perf_counter_t g_dma_perf;
static uint16_t dma_heap_inuse;
static uint16_t dma_heap_peak_use;
/****************************************************************************
* Public Functions
****************************************************************************/
__EXPORT int board_dma_alloc_init(void)
{
dma_allocator = gran_initialize(g_dma_heap,
sizeof(g_dma_heap),
7, /* 128B granule - must be > alignment (XXX bug?) */
6); /* 64B alignment */
if (dma_allocator == NULL) {
return -ENOMEM;
} else {
dma_heap_inuse = 0;
dma_heap_peak_use = 0;
g_dma_perf = perf_alloc(PC_COUNT, "dma_alloc");
}
return OK;
}
__EXPORT int board_get_dma_usage(uint16_t *dma_total, uint16_t *dma_used, uint16_t *dma_peak_used)
{
*dma_total = sizeof(g_dma_heap);
*dma_used = dma_heap_inuse;
*dma_peak_used = dma_heap_peak_use;
return OK;
}
/*
* DMA-aware allocator stubs for the FAT filesystem.
*/
__EXPORT void *fat_dma_alloc(size_t size);
__EXPORT void fat_dma_free(FAR void *memory, size_t size);
void *
fat_dma_alloc(size_t size)
{
void *rv = NULL;
perf_count(g_dma_perf);
rv = gran_alloc(dma_allocator, size);
if (rv != NULL) {
dma_heap_inuse += size;
if (dma_heap_inuse > dma_heap_peak_use) {
dma_heap_peak_use = dma_heap_inuse;
}
}
return rv;
}
void
fat_dma_free(FAR void *memory, size_t size)
{
gran_free(dma_allocator, memory, size);
dma_heap_inuse -= size;
}
#endif /* defined(BOARD_DMA_ALLOC_POOL_SIZE) */