[U-Boot] [PATCH 1/3]: arm: Kirkwood: Fix compiler optimization bug for kwgbe_send

[Prafulla Wadaskar]

> -----Original Message-----
> From: u-boot-bounces at lists.denx.de 
> [mailto:u-boot-bounces at lists.denx.de] On Behalf Of Simon Kagstrom
> Sent: Thursday, July 02, 2009 6:32 PM
> To: Simon Kagstrom
> Cc: U-Boot ML
> Subject: [U-Boot] [PATCH 1/3]: arm: Kirkwood: Fix compiler 
> optimization bug for kwgbe_send
> 
> Fix compiler optimization bug for kwgbe_send
> 
> kwgbe_send/recv both have loops waiting for the hardware to 
> set  a bit.
> GCC 4.3.3 cleverly optimizes the send case to ... a while(1); 
> loop. This patch makes the structure volatile to force 
> re-loading of the transmit descriptor.
> 
> Signed-off-by: Simon Kagstrom <simon.kagstrom at netinsight.net>
> ---
>  drivers/net/kirkwood_egiga.c |    6 +++---
>  1 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/kirkwood_egiga.c 
> b/drivers/net/kirkwood_egiga.c index 3c5db19..db55d9d 100644
> --- a/drivers/net/kirkwood_egiga.c
> +++ b/drivers/net/kirkwood_egiga.c
> @@ -484,9 +484,9 @@ static int kwgbe_halt(struct eth_device 
> *dev)  static int kwgbe_send(struct eth_device *dev, volatile 
> void *dataptr,
>  		      int datasize)
>  {
> -	struct kwgbe_device *dkwgbe = to_dkwgbe(dev);
> -	struct kwgbe_registers *regs = dkwgbe->regs;
> -	struct kwgbe_txdesc *p_txdesc = dkwgbe->p_txdesc;
> +	volatile struct kwgbe_device *dkwgbe = to_dkwgbe(dev);
> +	volatile struct kwgbe_registers *regs = dkwgbe->regs;
> +	volatile struct kwgbe_txdesc *p_txdesc = dkwgbe->p_txdesc;
Only p_txdesc needed volatile, not others...

Regards ....
Prafulla . .