Re: [net-next] net: stmmac: handle endianness in dwmac4_get_timestamp

[Alexandre Torgue]

On 2/14/19 7:09 PM, Florian Fainelli wrote:
> On 2/14/19 9:26 AM, Alexandre Torgue wrote:
> > GMAC IP is little-endian and used on several kind of CPU (big or little
> > endian). Main callbacks functions of the stmmac drivers take care about
> > it. It was not the case for dwmac4_get_timestamp function.
>
> This is clearly a bugfix, so you should be targeting the 'net' tree and
> provide a Fixes: tag so this can be backported to relevant stable kernels.

Ok Florian, I just have to find the right commit to fix :)

> > Signed-off-by: Alexandre Torgue <alexandre.torgue@xxxxxx>
> >
> > diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c
> > index 20299f6..736e296 100644
> > --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c
> > +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_descs.c
> > @@ -241,15 +241,18 @@ static inline void dwmac4_get_timestamp(void *desc, u32 ats, u64 *ts)
> >   static int dwmac4_rx_check_timestamp(void *desc)
> >   {
> >   	struct dma_desc *p = (struct dma_desc *)desc;
> > +	unsigned int rdes0 = le32_to_cpu(p->des0);
> > +	unsigned int rdes1 = le32_to_cpu(p->des1);
> > +	unsigned int rdes3 = le32_to_cpu(p->des3);
> >   	u32 own, ctxt;
> >   	int ret = 1;
> >   
> > -	own = p->des3 & RDES3_OWN;
> > -	ctxt = ((p->des3 & RDES3_CONTEXT_DESCRIPTOR)
> > +	own = rdes3 & RDES3_OWN;
> > +	ctxt = ((rdes3 & RDES3_CONTEXT_DESCRIPTOR)
> >   		>> RDES3_CONTEXT_DESCRIPTOR_SHIFT);
> >   
> >   	if (likely(!own && ctxt)) {
> > -		if ((p->des0 == 0xffffffff) && (p->des1 == 0xffffffff))
> > +		if ((rdes0 == 0xffffffff) && (rdes1 == 0xffffffff))
> >   			/* Corrupted value */
> >   			ret = -EINVAL;
> >   		else