RE: [PATCH v2] PCI: imx6: Support more than Gen2 speed link mode

[Hongxing Zhu <hongxing.zhu@xxxxxxx>]

> -----Original Message-----
> From: Bjorn Helgaas <helgaas@xxxxxxxxxx>
> Sent: 2022年7月21日 5:16
> To: Hongxing Zhu <hongxing.zhu@xxxxxxx>
> Cc: l.stach@xxxxxxxxxxxxxx; bhelgaas@xxxxxxxxxx;
> lorenzo.pieralisi@xxxxxxx; tharvey@xxxxxxxxxxxxx;
> linux-pci@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx; dl-linux-imx
> <linux-imx@xxxxxxx>
> Subject: Re: [PATCH v2] PCI: imx6: Support more than Gen2 speed link mode
> 
> On Wed, Jul 20, 2022 at 11:26:16AM +0800, Richard Zhu wrote:
> > Support more than Gen2 speed link mode, since i.MX8MP PCIe supports up
> to
> > Gen3 link speed.
> >
> > Link:
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> > Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx>
> > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> 
> You should not post patches with my signed-off-by.
> 
Okay, got that.

> I add my signed-off-by to patches when I merge them.
> 
> I applied this to pci/ctrl/imx6, replacing the v1 patch, thanks!
> 
Thanks a lot for your kindly help.

Best Regards
Richard Zhu

> > ---
> > Changes from v1:
> > - The Supported Link Speeds of the PCI_EXP_LNKCAP should be re-configured
> too.
> > - When only Gen1 is enabled, refine the dev_info accordingly.
> >
> > ---
> >  drivers/pci/controller/dwc/pci-imx6.c | 8 ++++----
> >  1 file changed, 4 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/pci/controller/dwc/pci-imx6.c
> b/drivers/pci/controller/dwc/pci-imx6.c
> > index e1ba11dabaa8..b66876f7efe0 100644
> > --- a/drivers/pci/controller/dwc/pci-imx6.c
> > +++ b/drivers/pci/controller/dwc/pci-imx6.c
> > @@ -844,12 +844,12 @@ static int imx6_pcie_start_link(struct dw_pcie
> *pci)
> >  	if (ret)
> >  		goto err_reset_phy;
> >
> > -	if (pci->link_gen == 2) {
> > -		/* Allow Gen2 mode after the link is up. */
> > +	if (pci->link_gen > 1) {
> > +		/* Allow faster modes after the link is up */
> >  		dw_pcie_dbi_ro_wr_en(pci);
> >  		tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
> >  		tmp &= ~PCI_EXP_LNKCAP_SLS;
> > -		tmp |= PCI_EXP_LNKCAP_SLS_5_0GB;
> > +		tmp |= pci->link_gen;
> >  		dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp);
> >
> >  		/*
> > @@ -884,7 +884,7 @@ static int imx6_pcie_start_link(struct dw_pcie *pci)
> >  		if (ret)
> >  			goto err_reset_phy;
> >  	} else {
> > -		dev_info(dev, "Link: Gen2 disabled\n");
> > +		dev_info(dev, "Link: Only Gen1 is enabled\n");
> >  	}
> >
> >  	imx6_pcie->link_is_up = true;
> > --
> > 2.25.1
> >
> >
> > _______________________________________________
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> > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> >
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