[U-Boot] [PATCH V2] kirkwood_egiga: bugfix: add DMA sequence points

[Prafulla Wadaskar]

> -----Original Message-----
> From: u-boot-bounces at lists.denx.de 
> [mailto:u-boot-bounces at lists.denx.de] On Behalf Of Albert Aribaud
> Sent: Saturday, July 10, 2010 7:11 PM
> To: u-boot at lists.denx.de
> Subject: [U-Boot] [PATCH V2] kirkwood_egiga: bugfix: add DMA 
> sequence points
> 
> 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 at free.fr>
> ---
> PATCHSET HISTORY
> 
> V1: initial submit
> V2: fixed badly placed isb()
> 
>  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));
>  
>  	/*

Acked-by: Prafulla Wadaskar <prafulla at marvell.com>

Regards..
Prafulla . .