kernel/arch/arm/mm/dma-mapping-nommu.c
2024-07-22 17:22:30 +08:00

54 lines
1.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Based on linux/arch/arm/mm/dma-mapping.c
*
* Copyright (C) 2000-2004 Russell King
*/
#include <linux/dma-map-ops.h>
#include <asm/cachetype.h>
#include <asm/cacheflush.h>
#include <asm/outercache.h>
#include <asm/cp15.h>
#include "dma.h"
void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
enum dma_data_direction dir)
{
dmac_map_area(__va(paddr), size, dir);
if (dir == DMA_FROM_DEVICE)
outer_inv_range(paddr, paddr + size);
else
outer_clean_range(paddr, paddr + size);
}
void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
enum dma_data_direction dir)
{
if (dir != DMA_TO_DEVICE) {
outer_inv_range(paddr, paddr + size);
dmac_unmap_area(__va(paddr), size, dir);
}
}
void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
const struct iommu_ops *iommu, bool coherent)
{
if (IS_ENABLED(CONFIG_CPU_V7M)) {
/*
* Cache support for v7m is optional, so can be treated as
* coherent if no cache has been detected. Note that it is not
* enough to check if MPU is in use or not since in absense of
* MPU system memory map is used.
*/
dev->dma_coherent = cacheid ? coherent : true;
} else {
/*
* Assume coherent DMA in case MMU/MPU has not been set up.
*/
dev->dma_coherent = (get_cr() & CR_M) ? coherent : true;
}
}