| Message ID | 20210715114953.24393-1-qiangqing.zhang@nxp.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | arm64: dts: imx8mp: remove fallback compatible string for FlexCAN | expand |
On 15.07.2021 09:03:55, Fabio Estevam wrote: > Hi Joakim, > > On Thu, Jul 15, 2021 at 8:49 AM Joakim Zhang <qiangqing.zhang@nxp.com> wrote: > > > > FlexCAN on i.MX8MP is not derived from i.MX6Q, instead resues from > > i.MX8QM with extra ECC added. With "fsl,imx6q-flexcan" compatible string, > > i.MX8MP FlexCAN would not work, so remove this fallback compatible string. > > I agree with the removal of "fsl,imx6q-flexcan", but I don't > understand your comment > saying that: > > "With "fsl,imx6q-flexcan" compatible string, i.MX8MP FlexCAN would not work" > > Why? Don't remember exactly why It doesn't work. I think it was a missing quirk that the imx6 doesn't need. > "fsl,imx8mp-flexcan" is passed as the more specific compatible string > and it should match against it first. ACK - but why specify the imx6 in the compatible list if the flexcan IP core isn't compatible with the one of the imx6? regards, Marc
Hi Marc, On Thu, Jul 15, 2021 at 9:33 AM Marc Kleine-Budde <mkl@pengutronix.de> wrote: > > Why? > > Don't remember exactly why It doesn't work. I think it was a missing > quirk that the imx6 doesn't need. > > > "fsl,imx8mp-flexcan" is passed as the more specific compatible string > > and it should match against it first. > > ACK - but why specify the imx6 in the compatible list if the flexcan IP > core isn't compatible with the one of the imx6? Correct. The change in this patch looks good. The commit log needs improvement though.
Hi Mac, Fabio, > -----Original Message----- > From: Marc Kleine-Budde <mkl@pengutronix.de> > Sent: 2021年7月15日 20:15 > To: Fabio Estevam <festevam@gmail.com> > Cc: Joakim Zhang <qiangqing.zhang@nxp.com>; Rob Herring > <robh+dt@kernel.org>; Shawn Guo <shawnguo@kernel.org>; Sascha Hauer > <s.hauer@pengutronix.de>; Sascha Hauer <kernel@pengutronix.de>; > dl-linux-imx <linux-imx@nxp.com>; open list:OPEN FIRMWARE AND FLATTENED > DEVICE TREE BINDINGS <devicetree@vger.kernel.org>; Aisheng Dong > <aisheng.dong@nxp.com> > Subject: Re: [PATCH] arm64: dts: imx8mp: remove fallback compatible string > for FlexCAN > > On 15.07.2021 09:03:55, Fabio Estevam wrote: > > Hi Joakim, > > > > On Thu, Jul 15, 2021 at 8:49 AM Joakim Zhang <qiangqing.zhang@nxp.com> > wrote: > > > > > > FlexCAN on i.MX8MP is not derived from i.MX6Q, instead resues from > > > i.MX8QM with extra ECC added. With "fsl,imx6q-flexcan" compatible > > > string, i.MX8MP FlexCAN would not work, so remove this fallback > compatible string. > > > > I agree with the removal of "fsl,imx6q-flexcan", but I don't > > understand your comment saying that: > > > > "With "fsl,imx6q-flexcan" compatible string, i.MX8MP FlexCAN would not > work" > > > > Why? > > Don't remember exactly why It doesn't work. I think it was a missing quirk that > the imx6 doesn't need. I could explain more if I remember correctly, i.MX8MP with ECC added and default is enabled, without FLEXCAN_QUIRK_DISABLE_MECR quirk, FlexCAN doesn't work, it will put device in freeze mode. However, as Mac described, i.MX6Q doesn't need it. > > "fsl,imx8mp-flexcan" is passed as the more specific compatible string > > and it should match against it first. > > ACK - but why specify the imx6 in the compatible list if the flexcan IP core isn't > compatible with the one of the imx6? Best Regards, Joakim Zhang > regards, > Marc > > -- > Pengutronix e.K. | Marc Kleine-Budde | > Embedded Linux | https://www.pengutronix.de | > Vertretung West/Dortmund | Phone: +49-231-2826-924 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
> -----Original Message----- > From: Fabio Estevam <festevam@gmail.com> > Sent: 2021年7月15日 20:40 > To: Marc Kleine-Budde <mkl@pengutronix.de> > Cc: Joakim Zhang <qiangqing.zhang@nxp.com>; Rob Herring > <robh+dt@kernel.org>; Shawn Guo <shawnguo@kernel.org>; Sascha Hauer > <s.hauer@pengutronix.de>; Sascha Hauer <kernel@pengutronix.de>; > dl-linux-imx <linux-imx@nxp.com>; open list:OPEN FIRMWARE AND FLATTENED > DEVICE TREE BINDINGS <devicetree@vger.kernel.org>; Aisheng Dong > <aisheng.dong@nxp.com> > Subject: Re: [PATCH] arm64: dts: imx8mp: remove fallback compatible string > for FlexCAN > > Hi Marc, > > On Thu, Jul 15, 2021 at 9:33 AM Marc Kleine-Budde <mkl@pengutronix.de> > wrote: > > > > Why? > > > > Don't remember exactly why It doesn't work. I think it was a missing > > quirk that the imx6 doesn't need. > > > > > "fsl,imx8mp-flexcan" is passed as the more specific compatible > > > string and it should match against it first. > > > > ACK - but why specify the imx6 in the compatible list if the flexcan > > IP core isn't compatible with the one of the imx6? > > Correct. The change in this patch looks good. > > The commit log needs improvement though. Ok, I will improve the commit message and then resend the patch. Best Regards, Joakim Zhang
On 16.07.2021 02:03:44, Joakim Zhang wrote: >>> "With "fsl,imx6q-flexcan" compatible string, i.MX8MP FlexCAN would >>> not work" >> >> Why? > I could explain more if I remember correctly, i.MX8MP with ECC added > and default is enabled, without FLEXCAN_QUIRK_DISABLE_MECR quirk, > FlexCAN doesn't work, it will put device in freeze mode. However, as > Mac described, i.MX6Q doesn't need it. The bits that are used in the FLEXCAN_QUIRK_DISABLE_MECR are marked as reserved on the imx6's flexcan IP core. Marc -- Pengutronix e.K. | Marc Kleine-Budde | Embedded Linux | https://www.pengutronix.de | Vertretung West/Dortmund | Phone: +49-231-2826-924 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi b/arch/arm64/boot/dts/freescale/imx8mp.dtsi index 9f7c7f587d38..1bfb359dba4a 100644 --- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi +++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi @@ -579,7 +579,7 @@ }; flexcan1: can@308c0000 { - compatible = "fsl,imx8mp-flexcan", "fsl,imx6q-flexcan"; + compatible = "fsl,imx8mp-flexcan"; reg = <0x308c0000 0x10000>; interrupts = <GIC_SPI 142 IRQ_TYPE_LEVEL_HIGH>; clocks = <&clk IMX8MP_CLK_IPG_ROOT>, @@ -594,7 +594,7 @@ }; flexcan2: can@308d0000 { - compatible = "fsl,imx8mp-flexcan", "fsl,imx6q-flexcan"; + compatible = "fsl,imx8mp-flexcan"; reg = <0x308d0000 0x10000>; interrupts = <GIC_SPI 144 IRQ_TYPE_LEVEL_HIGH>; clocks = <&clk IMX8MP_CLK_IPG_ROOT>,
FlexCAN on i.MX8MP is not derived from i.MX6Q, instead resues from i.MX8QM with extra ECC added. With "fsl,imx6q-flexcan" compatible string, i.MX8MP FlexCAN would not work, so remove this fallback compatible string. Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com> --- arch/arm64/boot/dts/freescale/imx8mp.dtsi | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)