[U-Boot] [PATCH v2 1/2] net: fec_mxc: Adjust RX DMA alignment for mx6solox

[Stefano Babic]

Hi Fabio,

On 20/08/2014 23:24, Fabio Estevam wrote:
> From: Fabio Estevam <fabio.estevam at freescale.com>
> 
> mx6solox has a requirement for 64 bytes alignment for RX DMA transfer.
> 
> Adjust it accordingly.
> 
> Signed-off-by: Fabio Estevam <fabio.estevam at freescale.com>
> ---
> Changes since v1:
> - Avoid too many ifdef's by providing a dma_rx_align() funtion as suggested
> by Otavio
> 
>  drivers/net/fec_mxc.c | 17 ++++++++++++++---
>  1 file changed, 14 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/fec_mxc.c b/drivers/net/fec_mxc.c
> index 4cefda4..1a5105e 100644
> --- a/drivers/net/fec_mxc.c
> +++ b/drivers/net/fec_mxc.c
> @@ -28,6 +28,8 @@ DECLARE_GLOBAL_DATA_PTR;
>   */
>  #define FEC_XFER_TIMEOUT	5000
>  
> +#define ARCH_DMA_MINALIGN_MX6SX	64
> +
>  #ifndef CONFIG_MII
>  #error "CONFIG_MII has to be defined!"
>  #endif
> @@ -267,6 +269,15 @@ static int fec_tx_task_disable(struct fec_priv *fec)
>  	return 0;
>  }
>  
> +static int dma_rx_align(void)
> +{
> +#ifdef CONFIG_MX6SX
> +	return	ARCH_DMA_MINALIGN_MX6SX;
> +#else
> +	return ARCH_DMA_MINALIGN;
> +#endif
> +}
> +

I go just a bit further according to Otavio's comment. In this way, we
do not remove #ifdef, we have only moved. What about using is_cpu_type()
instead of this ? If you do not want to add the macro for not mx6 socs
(preferable way, I think), the get_cpu_rev() should be available for all
i.MXes.

>  /**
>   * Initialize receive task's buffer descriptors
>   * @param[in] fec all we know about the device yet
> @@ -286,7 +297,7 @@ static void fec_rbd_init(struct fec_priv *fec, int count, int dsize)
>  	 * Reload the RX descriptors with default values and wipe
>  	 * the RX buffers.
>  	 */
> -	size = roundup(dsize, ARCH_DMA_MINALIGN);
> +	size = roundup(dsize, dma_rx_align());
>  	for (i = 0; i < count; i++) {
>  		data = (uint8_t *)fec->rbd_base[i].data_pointer;
>  		memset(data, 0, dsize);
> @@ -881,9 +892,9 @@ static int fec_alloc_descs(struct fec_priv *fec)
>  	/* Allocate RX buffers. */
>  
>  	/* Maximum RX buffer size. */
> -	size = roundup(FEC_MAX_PKT_SIZE, ARCH_DMA_MINALIGN);
> +	size = roundup(FEC_MAX_PKT_SIZE, dma_rx_align());
>  	for (i = 0; i < FEC_RBD_NUM; i++) {
> -		data = memalign(ARCH_DMA_MINALIGN, size);
> +		data = memalign(dma_rx_align(), size);
>  		if (!data) {
>  			printf("%s: error allocating rxbuf %d\n", __func__, i);
>  			goto err_ring;
> 

Best regards,
Stefano Babic

-- 
=====================================================================
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-53 Fax: +49-8142-66989-80 Email: sbabic at denx.de
=====================================================================