linux/arch/csky/mm/dma-mapping.c

89 lines
1.9 KiB
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
#include <linux/cache.h>
#include <linux/dma-map-ops.h>
#include <linux/genalloc.h>
#include <linux/highmem.h>
#include <linux/io.h>
#include <linux/mm.h>
#include <linux/scatterlist.h>
#include <linux/types.h>
#include <linux/version.h>
#include <asm/cache.h>
static inline void cache_op(phys_addr_t paddr, size_t size,
void (*fn)(unsigned long start, unsigned long end))
{
struct page *page = phys_to_page(paddr);
void *start = __va(page_to_phys(page));
unsigned long offset = offset_in_page(paddr);
size_t left = size;
do {
size_t len = left;
if (offset + len > PAGE_SIZE)
len = PAGE_SIZE - offset;
if (PageHighMem(page)) {
start = kmap_atomic(page);
fn((unsigned long)start + offset,
(unsigned long)start + offset + len);
kunmap_atomic(start);
} else {
fn((unsigned long)start + offset,
(unsigned long)start + offset + len);
}
offset = 0;
page++;
start += PAGE_SIZE;
left -= len;
} while (left);
}
static void dma_wbinv_set_zero_range(unsigned long start, unsigned long end)
{
memset((void *)start, 0, end - start);
dma_wbinv_range(start, end);
}
void arch_dma_prep_coherent(struct page *page, size_t size)
{
cache_op(page_to_phys(page), size, dma_wbinv_set_zero_range);
}
void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
enum dma_data_direction dir)
{
switch (dir) {
case DMA_TO_DEVICE:
cache_op(paddr, size, dma_wb_range);
break;
case DMA_FROM_DEVICE:
case DMA_BIDIRECTIONAL:
cache_op(paddr, size, dma_wbinv_range);
break;
default:
BUG();
}
}
void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
enum dma_data_direction dir)
{
switch (dir) {
case DMA_TO_DEVICE:
return;
case DMA_FROM_DEVICE:
case DMA_BIDIRECTIONAL:
cache_op(paddr, size, dma_inv_range);
break;
default:
BUG();
}
}