From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Subject: Re: [PATCH 1/3] ata: sata_dwc_460ex: use "dmas" DT property to find dma channel Date: Thu, 17 Dec 2015 18:53:04 +0200 Message-ID: <1450371184.30729.175.camel@linux.intel.com> References: <1450221935-6034-1-git-send-email-mans@mansr.com> <1450364395.30729.136.camel@linux.intel.com> <1450367702.30729.146.camel@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mga14.intel.com ([192.55.52.115]:38389 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756127AbbLQQzY (ORCPT ); Thu, 17 Dec 2015 11:55:24 -0500 In-Reply-To: Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: =?ISO-8859-1?Q?M=E5ns_Rullg=E5rd?= , Julian Margetson Cc: Tejun Heo , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org On Thu, 2015-12-17 at 16:04 +0000, M=C3=A5ns Rullg=C3=A5rd wrote: > Andy Shevchenko writes: >=20 > > On Thu, 2015-12-17 at 15:13 +0000, M=C3=A5ns Rullg=C3=A5rd wrote: > > > Andy Shevchenko writes: > > >=20 > > > > On Tue, 2015-12-15 at 23:34 +0000, M=C3=A5ns Rullg=C3=A5rd wrot= e: > > > > > Mans Rullgard writes: > > > > >=20 > > > > > > Currently this driver only works with a DesignWare DMA > > > > > > engine > > > > > > which it registers manually using the second "reg" address > > > > > > range and interrupt number from the DT node. > > > > > >=20 > > > > > > This patch makes the driver instead use the "dmas" property > > > > > > if > > > > > > present, otherwise optionally falling back on the old way > > > > > > so > > > > > > existing device trees can continue to work. > > > > > >=20 > > > > > > With this change, there is no longer any reason to depend > > > > > > on > > > > > > the 460EX machine type so drop that from Kconfig. > > > > > >=20 > > > > > > Signed-off-by: Mans Rullgard > > > > > > --- > > > > > > =C2=A0drivers/ata/Kconfig=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0|=C2=A0=C2=A010 ++- > > > > > > =C2=A0drivers/ata/sata_dwc_460ex.c | 192 > > > > > > +++++++++++++++++++++++++++-- > > > > > > -------------- > > > > > > =C2=A02 files changed, 131 insertions(+), 71 deletions(-) > > > > >=20 > > > > > The corresponding patch for the canyonlands devicetree looks > > > > > something > > > > > like this.=C2=A0=C2=A0I don't have any such hardware or even = a manual, > > > > > so I > > > > > don't > > > > > know what values to use for the various required DT > > > > > properties of > > > > > the > > > > > DMA controller node, nor can I test it.=C2=A0=C2=A0The SATA d= river > > > > > works > > > > > with a > > > > > different DMA controller on a Sigma Designs chip. > > > > >=20 > > > > > diff --git a/arch/powerpc/boot/dts/canyonlands.dts > > > > > b/arch/powerpc/boot/dts/canyonlands.dts > > > > > index 3dc75de..959f36e 100644 > > > > > --- a/arch/powerpc/boot/dts/canyonlands.dts > > > > > +++ b/arch/powerpc/boot/dts/canyonlands.dts > > > > > @@ -190,12 +190,22 @@ > > > > > =C2=A0 =C2=A0/* DMA */ 0x2 &UIC0 > > > > > 0xc > > > > > 0x4>; > > > > > =C2=A0 }; > > > > > =C2=A0 > > > > > + DMA0: dma@bffd0800 { > > > > > + compatible =3D "snps,dma-spear1340"; > > > > > + reg =3D <4 0xbffd0800 0x400>; > > > > > + interrupt-parent =3D <&UIC3>; > > > > > + interrupts =3D <0x5 0x4>; > > > > > + #dma-cells =3D <3>; > > > > > + /* required properties here */ > > > >=20 > > > > You have to move the master assignments and other custom > > > > dw_dmac > > > > properties. Maybe at some point I will fix that in > > > > dw/platform.c. > > > >=20 > > > > > + }; > > >=20 > > > The current sata_dwc driver calls dw_dma_probe() with null pdata > > > which causes the dw_dma driver to auto-detect most > > > parameters.=C2=A0=C2=A0It > > > looks like simply omitting those properties here results in the > > > same > > > thing, although in this case dw_dma_parse_dt() leaves a > > > devm-allocated pdata struct adrift.=C2=A0=C2=A0Deferring the allo= cation of > > > that > > > and changing the DT binding doc to make these properties optional > > > for > > > auto-detect-capable hardware should just work. > >=20 > > Yeah, I would like to allow autoconfiguration in case of DT as well > > and > > translate it to use unified device property API. > >=20 > > > Something like this: > >=20 > > If it works for you, please, submit as a patch. Thanks. >=20 > I can't test it since I have no such hardware. It's currently broken, last person who seems to have it is (was?)=C2=A0Julian Margetson [1] [1]=C2=A0https://patchwork.ozlabs.org/patch/439850/ --=20 Andy Shevchenko Intel Finland Oy