Re: [PATCH v5 45/48] net/wan/fsl_ucc_hdlc: fix reading of __be16 registers

[Li Yang]

On Mon, Nov 18, 2019 at 5:26 AM Rasmus Villemoes
<linux@xxxxxxxxxxxxxxxxxx> wrote:
>

Hi David,

What do you think about the patch 45-47 from the series for net
related changes?  If it is ok with you, I can merge them with the
whole series through the soc tree with your ACK.

Regards,
Leo

> When releasing the allocated muram resource, we rely on reading back
> the offsets from the riptr/tiptr registers. But those registers are
> __be16 (and we indeed write them using iowrite16be), so we can't just
> read them back with a normal C dereference.
>
> This is not currently a real problem, since for now the driver is
> PPC32-only. But it will soon be allowed to be used on arm and arm64 as
> well.
>
> Signed-off-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
> ---
>  drivers/net/wan/fsl_ucc_hdlc.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/wan/fsl_ucc_hdlc.c b/drivers/net/wan/fsl_ucc_hdlc.c
> index 405b24a5a60d..8d13586bb774 100644
> --- a/drivers/net/wan/fsl_ucc_hdlc.c
> +++ b/drivers/net/wan/fsl_ucc_hdlc.c
> @@ -732,8 +732,8 @@ static int uhdlc_open(struct net_device *dev)
>
>  static void uhdlc_memclean(struct ucc_hdlc_private *priv)
>  {
> -       qe_muram_free(priv->ucc_pram->riptr);
> -       qe_muram_free(priv->ucc_pram->tiptr);
> +       qe_muram_free(ioread16be(&priv->ucc_pram->riptr));
> +       qe_muram_free(ioread16be(&priv->ucc_pram->tiptr));
>
>         if (priv->rx_bd_base) {
>                 dma_free_coherent(priv->dev,
> --
> 2.23.0
>