Hi Lokesh, On Wed, Aug 10, 2016 at 7:02 AM, Lokesh Vutla <lokeshvu...@ti.com> wrote: > > > On Wednesday 10 August 2016 08:43 AM, Joe Hershberger wrote: >> Hi Lokesh >> >> On Tue, Aug 9, 2016 at 12:47 AM, Lokesh Vutla <lokeshvu...@ti.com> wrote: >>> cpsw tries to flush dcache which is not in the range of PKTSIZE. >>> Because of this the following warning comes while flushing: >>> >>> CACHE: Misaligned operation at range [dffecec0, dffed016] >>> >>> Fix it by flushing cache of size PKTSIZE_ALIGN as similar to what is >>> being done in _cpsw_recv. >>> >>> Signed-off-by: Lokesh Vutla <lokeshvu...@ti.com> >>> --- >>> Changes since v1: >>> - Use PKTALIGN instead of cache line size >>> - Need not align start of packet buffer from the network subsystem. >>> >>> drivers/net/cpsw.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/drivers/net/cpsw.c b/drivers/net/cpsw.c >>> index 2ce4ec6..8ce5716 100644 >>> --- a/drivers/net/cpsw.c >>> +++ b/drivers/net/cpsw.c >>> @@ -907,7 +907,7 @@ static int _cpsw_send(struct cpsw_priv *priv, void >>> *packet, int length) >>> int timeout = CPDMA_TIMEOUT; >>> >>> flush_dcache_range((unsigned long)packet, >>> - (unsigned long)packet + length); >>> + (unsigned long)packet + PKTSIZE_ALIGN); >> >> Technically you are flushing more than needed since you just need to >> be aligned to the cacheline beyond the size being sent, but you are >> flushing the maximum packet size every time. That said, it's still >> going to work and the code is readable. I'm fine with this, but wanted >> to make sure you knew this is more flushing than needed. > > Initially that was my idea as well and aligned length to cache line > size. As you suggested to use PKTSIZE_ALIGN and also _cpsw_recv uses the > same. So, I used PKTSIZE_ALIGN.
I actually recommended PKTALIGN, not PKTSIZE_ALIGN. For recv, the size for invalidate is unknown until it's received (unless you can check a descriptor after it's received but before you read it), so it's more appropriate to use PKTSIZE_ALIGN. For send, you certainly know the size before flushing. Cheers, -Joe _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
