linuxdebug/arch/hexagon/kernel/dma.c

45 lines
1.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* DMA implementation for Hexagon
*
* Copyright (c) 2010-2012, The Linux Foundation. All rights reserved.
*/
#include <linux/dma-map-ops.h>
#include <linux/memblock.h>
#include <asm/page.h>
void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
enum dma_data_direction dir)
{
void *addr = phys_to_virt(paddr);
switch (dir) {
case DMA_TO_DEVICE:
hexagon_clean_dcache_range((unsigned long) addr,
(unsigned long) addr + size);
break;
case DMA_FROM_DEVICE:
hexagon_inv_dcache_range((unsigned long) addr,
(unsigned long) addr + size);
break;
case DMA_BIDIRECTIONAL:
flush_dcache_range((unsigned long) addr,
(unsigned long) addr + size);
break;
default:
BUG();
}
}
/*
* Our max_low_pfn should have been backed off by 16MB in mm/init.c to create
* DMA coherent space. Use that for the pool.
*/
static int __init hexagon_dma_init(void)
{
return dma_init_global_coherent(PFN_PHYS(max_low_pfn),
hexagon_coherent_pool_size);
}
core_initcall(hexagon_dma_init);