From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Kirsher Subject: Re: [PATCH 1/5] e1000e: reset MAC-PHY interconnect on 82577/82578 Date: Tue, 16 Dec 2014 04:12:06 -0800 Message-ID: <1418731926.2467.15.camel@jtkirshe-mobl> References: <1418725700-31465-1-git-send-email-Yanjun.Zhu@windriver.com> <1418725700-31465-2-git-send-email-Yanjun.Zhu@windriver.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg="pgp-sha512"; protocol="application/pgp-signature"; boundary="=-WNfMXFYqBeKzLwVwwjBV" Cc: netdev@vger.kernel.org, w@1wt.eu, Zhu Yanjun , Bruce Allan , "David S. Miller" To: Zhu Yanjun , stable , Willy Tarreau Return-path: In-Reply-To: <1418725700-31465-2-git-send-email-Yanjun.Zhu@windriver.com> Sender: stable-owner@vger.kernel.org List-Id: netdev.vger.kernel.org --=-WNfMXFYqBeKzLwVwwjBV Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Tue, 2014-12-16 at 18:28 +0800, Zhu Yanjun wrote: > 2.6.x kernels require a similar logic change as commit 6dfaa76=20 > [e1000e: reset MAC-PHY interconnect on 82577/82578] introduces > for newer kernels. >=20 > During Sx->S0 transitions, the interconnect between the MAC and PHY on > 82577/82578 can remain in SMBus mode instead of transitioning to the > PCIe-like mode required during normal operation. Toggling the > LANPHYPC > Value bit essentially resets the interconnect forcing it to the > correct > mode. >=20 > after review of all intel drivers, found several instances where > drivers had the incorrect pattern of: > memory mapped write(); > delay(); >=20 > which should always be: > memory mapped write(); > write flush(); /* aka memory mapped read */ > delay(); >=20 > explanation: > The reason for including the flush is that writes can be held > (posted) in PCI/PCIe bridges, but the read always has to complete > synchronously and therefore has to flush all pending writes to a > device. If a write is held and followed by a delay, the delay > means nothing because the write may not have reached hardware > (maybe even not until the next read) >=20 > Signed-off-by: Bruce Allan > Signed-off-by: Jeff Kirsher > Signed-off-by: David S. Miller > Signed-off-by: Zhu Yanjun > --- > drivers/net/e1000e/defines.h | 2 ++ > drivers/net/e1000e/ich8lan.c | 20 ++++++++++++++++++++ > 2 files changed, 22 insertions(+) To be clear, Zhu is wanting this applied to stable trees (yet did not CC stable@vger.kernel.org ). Willy- I am fine with this series being applied to stable. --=-WNfMXFYqBeKzLwVwwjBV Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAABCgAGBQJUkCGWAAoJEOVv75VaS+3OJt4P/2gzZN/sLW9DrG7B04XFbKVZ 2oiJyImUtDy4gSj1aaiQL/c5cAu72pLyBSWGWlzT5Q2UFMjNpPK655ED1RE+EwqC b0r2kBhODgWIRCbSUvObS639kYvSkGDTM3TXAe5HW7ciLwwLQcnPAxoVXlAm4r+j 6zN/1EVx4Sm+IgikU+qerIZXynhq/q36EJNDHhs2m0OQjJ8bZSVfXz4VSPwOET5t IrtjW14lblAgWmI64kMJ172sd6rrhEc99kYlq6sdxNU3d3BQiwXyx/+ztnXVxd1b D7s3DHSTKY9BdGxDDNNRCbpBoYqO39oFt9VmwVt7MJiT2fSBXSV1Jx7Y1j3qWvnb zmv66f6lYnyz4BRAT9QrN6DscftipSb2ALiUUnQUCZjh++ngfol0Yao4UKa9nxzH Fk56cxK1XWuLWVPArNqheEKMstBilri6savbUCZvsJV3wAEMkMzxus1V+RvY70z/ Rx4DtTxK1befqlkZqQy7FmnlddDWy1MDXPOsxNFnnpTIzojj9RbSsWA1U2LAfxH4 AR7f1YaFfJTchx42TBJPrzh39h6pVpZpAgHps5xfnyz5uSQhKR+sAeu1E+nAptCc fOu9LGhFHwQ261dqJZxCQdUNLGduyNRfwuTRWqEyBmc7NHtjJ3GyIzjacynXdoGi jT8wdDYKsqit3OAt1JjX =jAX/ -----END PGP SIGNATURE----- --=-WNfMXFYqBeKzLwVwwjBV--