[PATCH v2 2/4] ARM: add flush_mem api for ARMv6

Gupta, Ramesh grgupta at ti.com
Tue Jun 19 07:21:16 EDT 2012


>From 630a3a8f341eb7f58f9a63bf786d732b5bdfd01e Mon Sep 17 00:00:00 2001
From: Ramesh Gupta G <grgupta at ti.com>
Date: Fri, 15 Jun 2012 16:39:21 +0530
Subject: [PATCH v2 2/4] ARM: add flush_mem api for ARMv6

Added flush_mem cache maintenance api for ARMv6.
The implementation is based on dma_flush_range.

Signed-off-by: Ramesh Gupta G <grgupta at ti.com>
---
 arch/arm/mm/cache-v6.S |   28 ++++++++++++++++++++++++++++
 1 files changed, 28 insertions(+), 0 deletions(-)

diff --git a/arch/arm/mm/cache-v6.S b/arch/arm/mm/cache-v6.S
index 74c2e5a..f91d847 100644
--- a/arch/arm/mm/cache-v6.S
+++ b/arch/arm/mm/cache-v6.S
@@ -328,6 +328,34 @@ ENTRY(v6_dma_unmap_area)
 	mov	pc, lr
 ENDPROC(v6_dma_unmap_area)

+/*
+ *	v6_flush_mem(start,end)
+ *	- start   - virtual start address of region
+ *	- end     - virtual end address of region
+ */
+ENTRY(v6_flush_mem)
+#ifdef CONFIG_DMA_CACHE_RWFO
+	ldrb	r2, [r0]		@ read for ownership
+	strb	r2, [r0]		@ write for ownership
+#endif
+	bic	r0, r0, #D_CACHE_LINE_SIZE - 1
+1:
+#ifdef HARVARD_CACHE
+	mcr	p15, 0, r0, c7, c14, 1		@ clean & invalidate D line
+#else
+	mcr	p15, 0, r0, c7, c15, 1		@ clean & invalidate line
+#endif
+	add	r0, r0, #D_CACHE_LINE_SIZE
+	cmp	r0, r1
+#ifdef CONFIG_DMA_CACHE_RWFO
+	ldrlob	r2, [r0]			@ read for ownership
+	strlob	r2, [r0]			@ write for ownership
+#endif
+	blo	1b
+	mov	r0, #0
+	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer
+	mov	pc, lr
+ENDPROC(v6_flush_mem)
 	__INITDATA

 	@ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
-- 
1.7.0.4


-- 
regards
Ramesh Gupta G



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