From ecfb8768b16ebf6781ee0df45742674bda8a9543 Mon Sep 17 00:00:00 2001
From: Peng Fan <Peng.Fan@freescale.com>
Date: Tue, 21 Jul 2015 16:15:21 +0800
Subject: [PATCH] mtd: nand: mxs invalidate dcache before DMA read
Follow linux dma flow:
Before DMA read, be sure to invalidate the cache over the address
range of DMA buffer to prevent cache coherency problems.
After DMA read, invalidate dcache again.
Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
Acked-by: Marek Vasut <marex@denx.de>
Acked-by: Tim Harvey <tharvey@gateworks.com>
---
drivers/mtd/nand/mxs_nand.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/mtd/nand/mxs_nand.c b/drivers/mtd/nand/mxs_nand.c
index 33ce8174dc..1d689015a5 100644
--- a/drivers/mtd/nand/mxs_nand.c
+++ b/drivers/mtd/nand/mxs_nand.c
@@ -462,6 +462,9 @@ static void mxs_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int length)
mxs_dma_desc_append(channel, d);
+ /* Invalidate caches */
+ mxs_nand_inval_data_buf(nand_info);
+
/* Execute the DMA chain. */
ret = mxs_dma_go(channel);
if (ret) {
@@ -628,6 +631,9 @@ static int mxs_nand_ecc_read_page(struct mtd_info *mtd, struct nand_chip *nand,
mxs_dma_desc_append(channel, d);
+ /* Invalidate caches */
+ mxs_nand_inval_data_buf(nand_info);
+
/* Execute the DMA chain. */
ret = mxs_dma_go(channel);
if (ret) {
--
2.39.5