[PATCH] txx9dmac: Fix clearing of CHAR register in 32-bit kernel

[PATCH] txx9dmac: Fix clearing of CHAR register in 32-bit kernel

[Atsushi Nemoto]

The CHAR register is 64-bit width but 32-bit kernel uses its lower
part only.  Be careful of initializing it.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
---
This patch is against linux-mips.org linux-queue tree.
Please queue this or fold into "DMA: TXx9 Soc DMA Controller driver" patch.

 drivers/dma/txx9dmac.c |   12 +++++++++++-
 1 files changed, 11 insertions(+), 1 deletions(-)

diff --git a/drivers/dma/txx9dmac.c b/drivers/dma/txx9dmac.c
index c655350..9aa9ea9 100644
--- a/drivers/dma/txx9dmac.c
+++ b/drivers/dma/txx9dmac.c
@@ -72,6 +72,16 @@ static void channel64_write_CHAR(const struct txx9dmac_chan *dc, dma_addr_t val)
 		channel64_writel(dc, CHAR, val);
 }
 
+static void channel64_clear_CHAR(const struct txx9dmac_chan *dc)
+{
+#if defined(CONFIG_32BIT) && !defined(CONFIG_64BIT_PHYS_ADDR)
+	channel64_writel(dc, CHAR, 0);
+	channel64_writel(dc, __pad_CHAR, 0);
+#else
+	channel64_writeq(dc, CHAR, 0);
+#endif
+}
+
 static dma_addr_t channel_read_CHAR(const struct txx9dmac_chan *dc)
 {
 	if (is_dmac64(dc))
@@ -318,7 +328,7 @@ static void txx9dmac_reset_chan(struct txx9dmac_chan *dc)
 {
 	channel_writel(dc, CCR, TXX9_DMA_CCR_CHRST);
 	if (is_dmac64(dc)) {
-		channel_writeq(dc, CHAR, 0);
+		channel64_clear_CHAR(dc);
 		channel_writeq(dc, SAR, 0);
 		channel_writeq(dc, DAR, 0);
 	} else {
-- 
1.5.6.3

Re: [PATCH] txx9dmac: Fix clearing of CHAR register in 32-bit kernel

[Ralf Baechle]

On Wed, Apr 29, 2009 at 12:11:15AM +0900, Atsushi Nemoto wrote:

> The CHAR register is 64-bit width but 32-bit kernel uses its lower
> part only.  Be careful of initializing it.
> 
> Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
> ---
> This patch is against linux-mips.org linux-queue tree.
> Please queue this or fold into "DMA: TXx9 Soc DMA Controller driver" patch.

Done.  Thanks!

  Ralf