Commit 7eacf185 authored by Will Deacon's avatar Will Deacon
Browse files

arm64: mm: Remove assembly DMA cache maintenance wrappers 



Remove the __dma_{flush,map,unmap}_area assembly wrappers and call the
appropriate cache maintenance functions directly from the DMA mapping
callbacks.

Reviewed-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Reviewed-by: default avatarArd Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20220610151228.4562-3-will@kernel.org


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent 4890cc18

arch/arm64/include/asm/cacheflush.h

+0 −7
Original line number Diff line number Diff line
@@ -104,13 +104,6 @@ static inline void flush_icache_range(unsigned long start, unsigned long end) 
}

#define flush_icache_range flush_icache_range



/*

 * Cache maintenance functions used by the DMA API. No to be used directly.

 */

extern void __dma_map_area(const void *, size_t, int);

extern void __dma_unmap_area(const void *, size_t, int);

extern void __dma_flush_area(const void *, size_t);



/*

 * Copy user data from/to a page which is mapped into a different

 * processes address space.  Really, we want to allow our "user

arch/arm64/mm/cache.S

+0 −41
Original line number Diff line number Diff line
@@ -194,44 +194,3 @@ SYM_FUNC_START(__pi_dcache_clean_pop) 
	ret

SYM_FUNC_END(__pi_dcache_clean_pop)

SYM_FUNC_ALIAS(dcache_clean_pop, __pi_dcache_clean_pop)
 


/*

 *	__dma_flush_area(start, size)

 *

 *	clean & invalidate D / U line

 *

 *	- start   - virtual start address of region

 *	- size    - size in question

 */

SYM_FUNC_START(__pi___dma_flush_area)

	add	x1, x0, x1

	dcache_by_line_op civac, sy, x0, x1, x2, x3

	ret

SYM_FUNC_END(__pi___dma_flush_area)

SYM_FUNC_ALIAS(__dma_flush_area, __pi___dma_flush_area)



/*

 *	__dma_map_area(start, size, dir)

 *	- start	- kernel virtual start address

 *	- size	- size of region

 *	- dir	- DMA direction

 */

SYM_FUNC_START(__pi___dma_map_area)

	add	x1, x0, x1

	b	__pi_dcache_clean_poc

SYM_FUNC_END(__pi___dma_map_area)

SYM_FUNC_ALIAS(__dma_map_area, __pi___dma_map_area)



/*

 *	__dma_unmap_area(start, size, dir)

 *	- start	- kernel virtual start address

 *	- size	- size of region

 *	- dir	- DMA direction

 */

SYM_FUNC_START(__pi___dma_unmap_area)

	add	x1, x0, x1

	cmp	w2, #DMA_TO_DEVICE

	b.ne	__pi_dcache_inval_poc

	ret

SYM_FUNC_END(__pi___dma_unmap_area)

SYM_FUNC_ALIAS(__dma_unmap_area, __pi___dma_unmap_area)

arch/arm64/mm/dma-mapping.c

+14 −5
Original line number Diff line number Diff line
@@ -16,18 +16,27 @@ 
void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,

			      enum dma_data_direction dir)

{

	__dma_map_area(phys_to_virt(paddr), size, dir);

	unsigned long start = (unsigned long)phys_to_virt(paddr);



	dcache_clean_poc(start, start + size);

}



void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,

			   enum dma_data_direction dir)

{

	__dma_unmap_area(phys_to_virt(paddr), size, dir);

	unsigned long start = (unsigned long)phys_to_virt(paddr);



	if (dir == DMA_TO_DEVICE)

		return;



	dcache_inval_poc(start, start + size);

}



void arch_dma_prep_coherent(struct page *page, size_t size)

{

	__dma_flush_area(page_address(page), size);

	unsigned long start = (unsigned long)page_address(page);



	dcache_clean_inval_poc(start, start + size);

}



#ifdef CONFIG_IOMMU_DMA