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sh: use the generic dma coherent remap allocator

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This switches to using common code for the DMA allocations, including
potential use of the CMA allocator if configured.

Switching to the generic code enables DMA allocations from atomic
context, which is required by the DMA API documentation, and also
adds various other minor features drivers start relying upon.  It
also makes sure we have on tested code base for all architectures
that require uncached pte bits for coherent DMA allocations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Rich Felker <dalias@libc.org>
This commit is contained in:
Christoph Hellwig 2020-07-14 14:18:56 +02:00 committed by Rich Felker
parent cd57d07b1e
commit 6dfdf673cc
2 changed files with 4 additions and 49 deletions
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2
arch/sh/Kconfig
View file

@ -137,7 +137,9 @@ config DMA_COHERENT
config DMA_NONCOHERENT
def_bool !NO_DMA && !DMA_COHERENT
select ARCH_HAS_DMA_PREP_COHERENT
select ARCH_HAS_SYNC_DMA_FOR_DEVICE
select DMA_DIRECT_REMAP
config PGTABLE_LEVELS
default 3 if X2TLB

51
arch/sh/kernel/dma-coherent.c
View file

@ -3,60 +3,13 @@
* Copyright (C) 2004 - 2007 Paul Mundt
*/
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/dma-noncoherent.h>
#include <linux/module.h>
#include <asm/cacheflush.h>
#include <asm/addrspace.h>
void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
gfp_t gfp, unsigned long attrs)
void arch_dma_prep_coherent(struct page *page, size_t size)
{
void *ret, *ret_nocache;
int order = get_order(size);
gfp |= __GFP_ZERO;
ret = (void *)__get_free_pages(gfp, order);
if (!ret)
return NULL;
/*
* Pages from the page allocator may have data present in
* cache. So flush the cache before using uncached memory.
*/
arch_sync_dma_for_device(virt_to_phys(ret), size,
DMA_BIDIRECTIONAL);
ret_nocache = (void __force *)ioremap(virt_to_phys(ret), size);
if (!ret_nocache) {
free_pages((unsigned long)ret, order);
return NULL;
}
split_page(pfn_to_page(virt_to_phys(ret) >> PAGE_SHIFT), order);
*dma_handle = virt_to_phys(ret);
if (!WARN_ON(!dev))
*dma_handle -= PFN_PHYS(dev->dma_pfn_offset);
return ret_nocache;
}
void arch_dma_free(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle, unsigned long attrs)
{
int order = get_order(size);
unsigned long pfn = (dma_handle >> PAGE_SHIFT);
int k;
if (!WARN_ON(!dev))
pfn += dev->dma_pfn_offset;
for (k = 0; k < (1 << order); k++)
__free_pages(pfn_to_page(pfn + k), 0);
iounmap(vaddr);
__flush_purge_region(page_address(page), size);
}
void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,