[PATCH 15/21] ARM: dma-mapping: always invalidate WT caches before DMA
From: Arnd Bergmann <arnd@kernel.org>
Date: 2023-03-27 12:17:42
Also in:
linux-arm-kernel, linux-m68k, linux-mips, linux-riscv, linux-sh, lkml, sparclinux
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
From: Arnd Bergmann <arnd@arndb.de> Most ARM CPUs can have write-back caches and that require cache management to be done in the dma_sync_*_for_device() operation. This is typically done in both writeback and writethrough mode. The cache-v4.S (arm720/740/7tdmi/9tdmi) and cache-v4wt.S (arm920t, arm940t) implementations are the exception here, and only do the cache management after the DMA is complete, in the dma_sync_*_for_cpu() operation. Change this for consistency with the other platforms. This should have no user visible effect. Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- arch/arm/mm/cache-v4.S | 8 ++++---- arch/arm/mm/cache-v4wt.S | 8 ++++---- 2 files changed, 8 insertions(+), 8 deletions(-)
diff --git a/arch/arm/mm/cache-v4.S b/arch/arm/mm/cache-v4.S
index 7787057e4990..e2b104876340 100644
--- a/arch/arm/mm/cache-v4.S
+++ b/arch/arm/mm/cache-v4.S@@ -117,23 +117,23 @@ ENTRY(v4_dma_flush_range) ret lr /* - * dma_unmap_area(start, size, dir) + * dma_map_area(start, size, dir) * - start - kernel virtual start address * - size - size of region * - dir - DMA direction */ -ENTRY(v4_dma_unmap_area) +ENTRY(v4_dma_map_area) teq r2, #DMA_TO_DEVICE bne v4_dma_flush_range /* FALLTHROUGH */ /* - * dma_map_area(start, size, dir) + * dma_unmap_area(start, size, dir) * - start - kernel virtual start address * - size - size of region * - dir - DMA direction */ -ENTRY(v4_dma_map_area) +ENTRY(v4_dma_unmap_area) ret lr ENDPROC(v4_dma_unmap_area) ENDPROC(v4_dma_map_area)
diff --git a/arch/arm/mm/cache-v4wt.S b/arch/arm/mm/cache-v4wt.S
index 0b290c25a99d..652218752f88 100644
--- a/arch/arm/mm/cache-v4wt.S
+++ b/arch/arm/mm/cache-v4wt.S@@ -172,24 +172,24 @@ v4wt_dma_inv_range: .equ v4wt_dma_flush_range, v4wt_dma_inv_range /* - * dma_unmap_area(start, size, dir) + * dma_map_area(start, size, dir) * - start - kernel virtual start address * - size - size of region * - dir - DMA direction */ -ENTRY(v4wt_dma_unmap_area) +ENTRY(v4wt_dma_map_area) add r1, r1, r0 teq r2, #DMA_TO_DEVICE bne v4wt_dma_inv_range /* FALLTHROUGH */ /* - * dma_map_area(start, size, dir) + * dma_unmap_area(start, size, dir) * - start - kernel virtual start address * - size - size of region * - dir - DMA direction */ -ENTRY(v4wt_dma_map_area) +ENTRY(v4wt_dma_unmap_area) ret lr ENDPROC(v4wt_dma_unmap_area) ENDPROC(v4wt_dma_map_area)
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2.39.2