From 0dc294c05d9df09ca4a65071e370247eaab8638d Mon Sep 17 00:00:00 2001
From: Ralf Baechle <ralf@linux-mips.org>
Date: Tue, 11 Nov 2014 22:22:03 +0100
Subject: [PATCH] MIPS: DMA: Explain the lack of special handling for
R14000/R16000.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
---
arch/mips/mm/dma-default.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/arch/mips/mm/dma-default.c b/arch/mips/mm/dma-default.c
index 33ba3c558fe4f..af5f046e627e4 100644
--- a/arch/mips/mm/dma-default.c
+++ b/arch/mips/mm/dma-default.c
@@ -61,6 +61,11 @@ static inline struct page *dma_addr_to_page(struct device *dev,
* Warning on the terminology - Linux calls an uncached area coherent;
* MIPS terminology calls memory areas with hardware maintained coherency
* coherent.
+ *
+ * Note that the R14000 and R16000 should also be checked for in this
+ * condition. However this function is only called on non-I/O-coherent
+ * systems and only the R10000 and R12000 are used in such systems, the
+ * SGI IP28 Indigo² rsp. SGI IP32 aka O2.
*/
static inline int cpu_needs_post_dma_flush(struct device *dev)
{
--
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