From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfram Sang Subject: Re: [PATCH resend] sdhci: work around broken dma boundary behaviour Date: Mon, 14 Mar 2011 18:21:29 +0100 Message-ID: <20110314172129.GA20654@pengutronix.de> References: <1299530457-19904-1-git-send-email-mmvinni@yahoo.com> <20110312214348.GA312@pengutronix.de> <423716.64271.qm@web161805.mail.bf1.yahoo.com> <20110314101829.GB2206@pengutronix.de> <470477.34668.qm@web161814.mail.bf1.yahoo.com> <20110314152817.GD2206@pengutronix.de> <727376.43956.qm@web161815.mail.bf1.yahoo.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="VS++wcV0S1rZb1Fb" Return-path: Received: from metis.ext.pengutronix.de ([92.198.50.35]:52656 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751310Ab1CNRVb (ORCPT ); Mon, 14 Mar 2011 13:21:31 -0400 Content-Disposition: inline In-Reply-To: <727376.43956.qm@web161815.mail.bf1.yahoo.com> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Mikko Vinni Cc: linux-mmc@vger.kernel.org --VS++wcV0S1rZb1Fb Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > > > intmask) > > > * boundaries, but as we can't disable the feature > > > * we need to at least restart the transfer. > > > */ > > > - if (intmask & SDHCI_INT_DMA_END) > > > - sdhci_writel(host, sdhci_readl(host, SDHCI_DMA_ADDRESS= ), > > > - SDHCI_DMA_ADDRESS); > > > + if (intmask & SDHCI_INT_DMA_END) { > > > + u32 dmastart, dmanow; > > > + dmastart =3D sg_dma_address(host->data->sg); > >=20 > > Consecutive transfers won't work (I know you know ;)). >=20 > I assume you mean a single transfer that exceeds whatever is > defined in SDHCI_DEFAULT_BOUNDARY_SIZE. As long as > it is kept at 512K things should be fine, but adding the auxiliary > variable to facilitate smaller values would make the patch > more invasive. Being an mmc non-hacker, I would rather leave > that kind of invasive patches for others :) If you don't want to invest the effort, this is your decision, which is fine. Other than that, I'd say you are not missing the required skills for that change. (/me is just helping out here as well) Cheers, Wolfram --=20 Pengutronix e.K. | Wolfram Sang | Industrial Linux Solutions | http://www.pengutronix.de/ | --VS++wcV0S1rZb1Fb Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iEYEARECAAYFAk1+TpkACgkQD27XaX1/VRvSsACeIM2N7JBWvD/RiggFDfrCenOv xhIAoKufx0y+r9EtFtOv7K2nPgQEreFx =EuTX -----END PGP SIGNATURE----- --VS++wcV0S1rZb1Fb--