[PATCH v3 09/31] arm64: Cache maintenance routines

Arnd Bergmann arnd at arndb.de
Fri Sep 7 15:28:09 EDT 2012


On Friday 07 September 2012, Catalin Marinas wrote:
> +
> +/*
> + *	dmac_inv_range(start,end)

all of these appear to be unused now. Can you remove them?

> + *	Invalidate the data cache within the specified region; we will be
> + *	performing a DMA operation in this region and we want to purge old
> + *	data in the cache.
> + *
> + *	- start   - virtual start address of region
> + *	- end     - virtual end address of region
> + */
> +ENTRY(dmac_inv_range)
> +	dcache_line_size x2, x3
> +	sub	x3, x2, #1
> +	bic	x0, x0, x3
> +	bic	x1, x1, x3
> +1:	dc	ivac, x0			// invalidate D / U line
> +	add	x0, x0, x2
> +	cmp	x0, x1
> +	b.lo	1b
> +	dsb	sy
> +	ret
> +ENDPROC(dmac_inv_range)
> +
> +/*
> + *	dmac_clean_range(start,end)
> + *	- start   - virtual start address of region
> + *	- end     - virtual end address of region
> + */
> +ENTRY(dmac_clean_range)
> +	dcache_line_size x2, x3
> +	sub	x3, x2, #1
> +	bic	x0, x0, x3
> +1:	dc	cvac, x0			// clean D / U line
> +	add	x0, x0, x2
> +	cmp	x0, x1
> +	b.lo	1b
> +	dsb	sy
> +	ret
> +ENDPROC(dmac_clean_range)
> +
> +/*
> + *	dmac_flush_range(start,end)
> + *	- start   - virtual start address of region
> + *	- end     - virtual end address of region
> + */
> +ENTRY(dmac_flush_range)
> +	dcache_line_size x2, x3
> +	sub	x3, x2, #1
> +	bic	x0, x0, x3
> +1:	dc	civac, x0			// clean & invalidate D / U line
> +	add	x0, x0, x2
> +	cmp	x0, x1
> +	b.lo	1b
> +	dsb	sy
> +	ret
> +ENDPROC(dmac_flush_range)
> +
> +/*
> + *	dmac_map_area(start, size, dir)
> + *	- start	- kernel virtual start address
> + *	- size	- size of region
> + *	- dir	- DMA direction
> + */
> +ENTRY(dmac_map_area)
> +	add	x1, x1, x0
> +	cmp	x2, #DMA_FROM_DEVICE
> +	b.eq	dmac_inv_range
> +	b	dmac_clean_range
> +ENDPROC(dmac_map_area)
> +
> +/*
> + *	dmac_unmap_area(start, size, dir)
> + *	- start	- kernel virtual start address
> + *	- size	- size of region
> + *	- dir	- DMA direction
> + */
> +ENTRY(dmac_unmap_area)
> +	add	x1, x1, x0
> +	cmp	x2, #DMA_TO_DEVICE
> +	b.ne	dmac_inv_range
> +	ret
> +ENDPROC(dmac_unmap_area)


Aside from this:

Acked-by: Arnd Bergmann <arnd at arndb.de>



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