Date: Thu, 14 May 2009 21:37:12 -0600 (MDT) From: "M. Warner Losh" <imp@bsdimp.com> To: stas@FreeBSD.org Cc: svn-src-head@FreeBSD.org, svn-src-all@FreeBSD.org, src-committers@FreeBSD.org Subject: Re: svn commit: r192027 - head/sys/arm/at91 Message-ID: <20090514.213712.-404854369.imp@bsdimp.com> In-Reply-To: <200905122114.n4CLEag9033208@svn.freebsd.org> References: <200905122114.n4CLEag9033208@svn.freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
In message: <200905122114.n4CLEag9033208@svn.freebsd.org>
Stanislav Sedov <stas@FreeBSD.org> writes:
: @@ -926,6 +937,7 @@ atestart_locked(struct ifnet *ifp)
: * tell the hardware to xmit the packet.
: */
: WR4(sc, ETH_TAR, segs[0].ds_addr);
: + BARRIER(sc, ETH_TAR, 8, BUS_SPACE_BARRIER_WRITE);
: WR4(sc, ETH_TCR, segs[0].ds_len);
Why is a barrier needed here?
Warner
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20090514.213712.-404854369.imp>