[U-Boot] [PATCH] kirkwood_egiga: bugfix: add DMA sequence points

[U-Boot] [PATCH] kirkwood_egiga: bugfix: add DMA sequence points

[Albert Aribaud]

Insert isb() sequence points to ensure DMA descriptors
are filled in and set up before actual DMA occurs.

Signed-off-by: Albert Aribaud <albert.aribaud@free.fr>
---
 drivers/net/kirkwood_egiga.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/drivers/net/kirkwood_egiga.c b/drivers/net/kirkwood_egiga.c
index 932792e..9eca2f3 100644
--- a/drivers/net/kirkwood_egiga.c
+++ b/drivers/net/kirkwood_egiga.c
@@ -447,6 +447,8 @@ static int kwgbe_init(struct eth_device *dev)
 
 	/* Assignment of Rx CRDB of given RXUQ */
 	KWGBEREG_WR(regs->rxcdp[RXUQ], (u32) dkwgbe->p_rxdesc_curr);
+	/* ensure previous write is done before enabling Rx DMA */
+	isb();
 	/* Enable port Rx. */
 	KWGBEREG_WR(regs->rqc, (1 << RXUQ));
 
@@ -536,6 +538,9 @@ static int kwgbe_send(struct eth_device *dev, volatile void *dataptr,
 	p_txdesc->buf_ptr = (u8 *) p;
 	p_txdesc->byte_cnt = datasize;
 
+	/* ensure tx desc writes above are performed before we start Tx DMA */
+	isb();
+
 	/* Apply send command using zeroth TXUQ */
 	KWGBEREG_WR(regs->tcqdp[TXUQ], (u32) p_txdesc);
 	KWGBEREG_WR(regs->tqc, (1 << TXUQ));
-- 
1.6.4.4

[U-Boot] [PATCH] kirkwood_egiga: bugfix: add DMA sequence points

[Albert ARIBAUD]

Please disregard. I have misplaced the second isb().

> @@ -536,6 +538,9 @@ static int kwgbe_send(struct eth_device *dev, volatile void *dataptr,
>   	p_txdesc->buf_ptr = (u8 *) p;
>   	p_txdesc->byte_cnt = datasize;
>
> +	/* ensure tx desc writes above are performed before we start Tx DMA */
> +	isb();
> +
>   	/* Apply send command using zeroth TXUQ */
>   	KWGBEREG_WR(regs->tcqdp[TXUQ], (u32) p_txdesc);
>   	KWGBEREG_WR(regs->tqc, (1<<  TXUQ));

It should actually apprear right before the write to tqc.

Resending correct patch.

Amicalement,
-- 
Albert.

[U-Boot] [PATCH] kirkwood_egiga: bugfix: add DMA sequence points

[Albert ARIBAUD]

Le 10/07/2010 15:23, Prafulla Wadaskar a ?crit :
> When you repost the patch, you should change its version and change log, this is standard procedure to be followed, now there are two patches on mailing list with same subject, confusing for custodian to pick right one ......
>
> Regards..
> Prafulla . .

Do you want me to repost as V2 ?

Amicalement,
-- 
Albert.

[U-Boot] [PATCH] kirkwood_egiga: bugfix: add DMA sequence points

[Prafulla Wadaskar]

When you repost the patch, you should change its version and change log, this is standard procedure to be followed, now there are two patches on mailing list with same subject, confusing for custodian to pick right one ......

Regards..
Prafulla . . 

[U-Boot] [PATCH] kirkwood_egiga: bugfix: add DMA sequence points

[Albert Aribaud]

Insert isb() sequence points to ensure DMA descriptors
are filled in and set up before actual DMA occurs.

Signed-off-by: Albert Aribaud <albert.aribaud@free.fr>
---
 drivers/net/kirkwood_egiga.c |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/drivers/net/kirkwood_egiga.c b/drivers/net/kirkwood_egiga.c
index 932792e..ea0c522 100644
--- a/drivers/net/kirkwood_egiga.c
+++ b/drivers/net/kirkwood_egiga.c
@@ -447,6 +447,8 @@ static int kwgbe_init(struct eth_device *dev)
 
 	/* Assignment of Rx CRDB of given RXUQ */
 	KWGBEREG_WR(regs->rxcdp[RXUQ], (u32) dkwgbe->p_rxdesc_curr);
+	/* ensure previous write is done before enabling Rx DMA */
+	isb();
 	/* Enable port Rx. */
 	KWGBEREG_WR(regs->rqc, (1 << RXUQ));
 
@@ -536,8 +538,13 @@ static int kwgbe_send(struct eth_device *dev, volatile void *dataptr,
 	p_txdesc->buf_ptr = (u8 *) p;
 	p_txdesc->byte_cnt = datasize;
 
-	/* Apply send command using zeroth TXUQ */
+	/* Set this tc desc as zeroth TXUQ */
 	KWGBEREG_WR(regs->tcqdp[TXUQ], (u32) p_txdesc);
+
+	/* ensure tx desc writes above are performed before we start Tx DMA */
+	isb();
+
+	/* Apply send command using zeroth TXUQ */
 	KWGBEREG_WR(regs->tqc, (1 << TXUQ));
 
 	/*
-- 
1.6.4.4