kernel_samsung_a34x-permissive/arch/microblaze/kernel/dma.c
2024-04-28 15:49:01 +02:00

67 lines
1.7 KiB
C
Executable file

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2009-2010 PetaLogix
* Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corporation
*
* Provide default implementations of the DMA mapping callbacks for
* directly mapped busses.
*/
#include <linux/device.h>
#include <linux/dma-noncoherent.h>
#include <linux/gfp.h>
#include <linux/dma-debug.h>
#include <linux/export.h>
#include <linux/bug.h>
#include <asm/cacheflush.h>
static void __dma_sync(struct device *dev, phys_addr_t paddr, size_t size,
enum dma_data_direction direction)
{
switch (direction) {
case DMA_TO_DEVICE:
case DMA_BIDIRECTIONAL:
flush_dcache_range(paddr, paddr + size);
break;
case DMA_FROM_DEVICE:
invalidate_dcache_range(paddr, paddr + size);
break;
default:
BUG();
}
}
void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,
size_t size, enum dma_data_direction dir)
{
__dma_sync(dev, paddr, size, dir);
}
void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
size_t size, enum dma_data_direction dir)
{
__dma_sync(dev, paddr, size, dir);
}
int arch_dma_mmap(struct device *dev, struct vm_area_struct *vma,
void *cpu_addr, dma_addr_t handle, size_t size,
unsigned long attrs)
{
#ifdef CONFIG_MMU
unsigned long user_count = vma_pages(vma);
unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
unsigned long off = vma->vm_pgoff;
unsigned long pfn;
if (off >= count || user_count > (count - off))
return -ENXIO;
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
pfn = consistent_virt_to_pfn(cpu_addr);
return remap_pfn_range(vma, vma->vm_start, pfn + off,
vma->vm_end - vma->vm_start, vma->vm_page_prot);
#else
return -ENXIO;
#endif
}