RE: [PATCH v2 1/7] reset: imx7: Add the iMX8MP PCIe PHY PERST support

[Hongxing Zhu]

Hi Philipp:

> -----Original Message-----
> From: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
> Sent: 2022年4月4日 17:34
> To: Hongxing Zhu <hongxing.zhu@xxxxxxx>; l.stach@xxxxxxxxxxxxxx;
> bhelgaas@xxxxxxxxxx; lorenzo.pieralisi@xxxxxxx; robh@xxxxxxxxxx;
> shawnguo@xxxxxxxxxx; vkoul@xxxxxxxxxx; alexander.stein@xxxxxxxxxxxxxxx
> Cc: linux-phy@xxxxxxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx;
> linux-pci@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx; dl-linux-imx
> <linux-imx@xxxxxxx>
> Subject: Re: [PATCH v2 1/7] reset: imx7: Add the iMX8MP PCIe PHY PERST
> support
> 
> Hi Richard,
> 
> On Mo, 2022-03-07 at 17:07 +0800, Richard Zhu wrote:
> > Add the i.MX8MP PCIe PHY PERST support.
> >
> > Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx>
> > ---
> >  drivers/reset/reset-imx7.c | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/drivers/reset/reset-imx7.c b/drivers/reset/reset-imx7.c
> > index 185a333df66c..d2408725eb2c 100644
> > --- a/drivers/reset/reset-imx7.c
> > +++ b/drivers/reset/reset-imx7.c
> > @@ -329,6 +329,7 @@ static int imx8mp_reset_set(struct
> > reset_controller_dev *rcdev,
> >                 break;
> >
> >         case IMX8MP_RESET_PCIE_CTRL_APPS_EN:
> > +       case IMX8MP_RESET_PCIEPHY_PERST:
> >                 value = assert ? 0 : bit;
> >                 break;
> >         }
> 
> This doesn't do what the commit description says.
> 
> The PCIEPHY_PERST bit is already supported by the driver (albeit
> incorrectly?) - this patch just inverts the bit.
> 
> Since this bit is not inverted on the other platforms, and the i.MX8MP
> reference manual says nothing about this, please explicitly state why this
> needs to be inverted and call it a fix in the commit description.
Thanks for your comments, and sorry for replying late.
I didn't get more details about this bit difference between i.MX8MP and others.
Let me consult with design team again, and back to you later.

Best Regards
Richard Zhu

> 
> regards
> Philipp