[PATCH v2] arm64: mm: convert __dma_* routines to use start, size
From: robin.murphy@arm.com (Robin Murphy)
Date: 2016-07-26 10:43:09
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On 26/07/16 08:34, Kwangwoo Lee wrote:
v2)
change __dma_* routine names using the terminoloy guidance:
area: takes a start and size
range: takes a start and end
use __dma_flush_area() instead of __dma_flush_range() in dma-mapping.c
v1)
__dma_* routines have been converted to use start and size instread of
start and end addresses. The patch was origianlly for adding
__clean_dcache_area_poc() which will be used in pmem driver to clean
dcache to the PoC(Point of Coherency) in arch_wb_cache_pmem().
The functionality of __clean_dcache_area_poc() was equivalent to
__dma_clean_range(). The difference was __dma_clean_range() uses the end
address, but __clean_dcache_area_poc() uses the size to clean.
Thus, __clean_dcache_area_poc() has been revised with a fall through
function of __dma_clean_range() after the change that __dma_* routines
use start and size instead of using start and end.
Signed-off-by: Kwangwoo Lee <redacted>
---Nit: the changelog relative to the previous posting wants to be here, under the "---" separator; the commit message above should describe the _current_ state of the patch, as that's all we'll really care about once it's in the Git history.
quoted hunk ↗ jump to hunk
arch/arm64/include/asm/cacheflush.h | 3 +- arch/arm64/mm/cache.S | 71 +++++++++++++++++++------------------ arch/arm64/mm/dma-mapping.c | 6 ++-- 3 files changed, 41 insertions(+), 39 deletions(-)diff --git a/arch/arm64/include/asm/cacheflush.h b/arch/arm64/include/asm/cacheflush.h index c64268d..2e5fb97 100644 --- a/arch/arm64/include/asm/cacheflush.h +++ b/arch/arm64/include/asm/cacheflush.h@@ -68,6 +68,7 @@ extern void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end); extern void flush_icache_range(unsigned long start, unsigned long end); extern void __flush_dcache_area(void *addr, size_t len); +extern void __clean_dcache_area_poc(void *addr, size_t len); extern void __clean_dcache_area_pou(void *addr, size_t len); extern long __flush_cache_user_range(unsigned long start, unsigned long end);@@ -85,7 +86,7 @@ static inline void flush_cache_page(struct vm_area_struct *vma, */ extern void __dma_map_area(const void *, size_t, int); extern void __dma_unmap_area(const void *, size_t, int); -extern void __dma_flush_range(const void *, const void *); +extern void __dma_flush_area(const void *, size_t); /* * Copy user data from/to a page which is mapped into a differentdiff --git a/arch/arm64/mm/cache.S b/arch/arm64/mm/cache.S index 50ff9ba..4415c1b 100644 --- a/arch/arm64/mm/cache.S +++ b/arch/arm64/mm/cache.S@@ -110,14 +110,16 @@ ENDPROC(__clean_dcache_area_pou) * - end - end address of region */ ENTRY(__inval_cache_range) + sub x1, x1, x0
Rather than doing this, I think it would be more sensible to simply swap the entry points.
quoted hunk ↗ jump to hunk
/* FALLTHROUGH */ /* - * __dma_inv_range(start, end) + * __dma_inv_area(start, size) * - start - virtual start address of region - * - end - virtual end address of region + * - size - size in question */ -__dma_inv_range: +__dma_inv_area: + add x1, x1, x0 dcache_line_size x2, x3 sub x3, x2, #1 tst x1, x3 // end cache line aligned?@@ -136,46 +138,47 @@ __dma_inv_range: dsb sy ret ENDPIPROC(__inval_cache_range) -ENDPROC(__dma_inv_range) +ENDPROC(__dma_inv_area) + +/* + * __clean_dcache_area_poc(kaddr, size) + * + * Ensure that any D-cache lines for the interval [kaddr, kaddr+size) + * are cleaned to the PoC. + * + * - kaddr - kernel address + * - size - size in question + */ +ENTRY(__clean_dcache_area_poc) + /* FALLTHROUGH */ /* - * __dma_clean_range(start, end) + * __dma_clean_area(start, size) * - start - virtual start address of region - * - end - virtual end address of region + * - size - size in question */ -__dma_clean_range: - dcache_line_size x2, x3 - sub x3, x2, #1 - bic x0, x0, x3 -1: +__dma_clean_area: alternative_if_not ARM64_WORKAROUND_CLEAN_CACHE - dc cvac, x0 + dcache_by_line_op cvac, sy, x0, x1, x2, x3 alternative_else - dc civac, x0 + dcache_by_line_op civac, sy, x0, x1, x2, x3
dcache_by_line_op is a relatively large macro - is there any way we can still apply the alternative to just the one instruction which needs it, as opposed to having to patch the entire mostly-identical routine? Robin.
quoted hunk ↗ jump to hunk
alternative_endif - add x0, x0, x2 - cmp x0, x1 - b.lo 1b - dsb sy ret -ENDPROC(__dma_clean_range) +ENDPIPROC(__clean_dcache_area_poc) +ENDPROC(__dma_clean_area) /* - * __dma_flush_range(start, end) + * __dma_flush_area(start, size) + * + * clean & invalidate D / U line + * * - start - virtual start address of region - * - end - virtual end address of region + * - size - size in question */ -ENTRY(__dma_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 +ENTRY(__dma_flush_area) + dcache_by_line_op civac, sy, x0, x1, x2, x3 ret -ENDPIPROC(__dma_flush_range) +ENDPIPROC(__dma_flush_area) /* * __dma_map_area(start, size, dir)@@ -184,10 +187,9 @@ ENDPIPROC(__dma_flush_range) * - dir - DMA direction */ ENTRY(__dma_map_area) - add x1, x1, x0 cmp w2, #DMA_FROM_DEVICE - b.eq __dma_inv_range - b __dma_clean_range + b.eq __dma_inv_area + b __dma_clean_area ENDPIPROC(__dma_map_area) /*@@ -197,8 +199,7 @@ ENDPIPROC(__dma_map_area) * - dir - DMA direction */ ENTRY(__dma_unmap_area) - add x1, x1, x0 cmp w2, #DMA_TO_DEVICE - b.ne __dma_inv_range + b.ne __dma_inv_area ret ENDPIPROC(__dma_unmap_area)diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c index c566ec8..e0b0712 100644 --- a/arch/arm64/mm/dma-mapping.c +++ b/arch/arm64/mm/dma-mapping.c@@ -165,7 +165,7 @@ static void *__dma_alloc(struct device *dev, size_t size, return ptr; /* remove any dirty cache lines on the kernel alias */ - __dma_flush_range(ptr, ptr + size); + __dma_flush_area(ptr, size); /* create a coherent mapping */ page = virt_to_page(ptr);@@ -377,7 +377,7 @@ static int __init atomic_pool_init(void) void *page_addr = page_address(page); memset(page_addr, 0, atomic_pool_size); - __dma_flush_range(page_addr, page_addr + atomic_pool_size); + __dma_flush_area(page_addr, atomic_pool_size); atomic_pool = gen_pool_create(PAGE_SHIFT, -1); if (!atomic_pool)@@ -535,7 +535,7 @@ fs_initcall(dma_debug_do_init); /* Thankfully, all cache ops are by VA so we can ignore phys here */ static void flush_page(struct device *dev, const void *virt, phys_addr_t phys) { - __dma_flush_range(virt, virt + PAGE_SIZE); + __dma_flush_area(virt, PAGE_SIZE); } static void *__iommu_alloc_attrs(struct device *dev, size_t size,