RE: [PATCH] PCI: imx6: Fix i.MX8MP PCIe EP can not trigger MSI

[Hongxing Zhu]

> -----Original Message-----
> From: Frank Li <frank.li@xxxxxxx>
> Sent: 2024年3月22日 2:49
> To: Hongxing Zhu <hongxing.zhu@xxxxxxx>
> Cc: l.stach@xxxxxxxxxxxxxx; bhelgaas@xxxxxxxxxx; lorenzo.pieralisi@xxxxxxx;
> marex@xxxxxxx; manivannan.sadhasivam@xxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx;
> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> kernel@xxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx>
> Subject: Re: [PATCH] PCI: imx6: Fix i.MX8MP PCIe EP can not trigger MSI
> 
> On Wed, Mar 20, 2024 at 11:45:38AM +0800, Richard Zhu wrote:
> > Fix i.MX8MP PCIe EP can't trigger MSI issue.
> > There is one 64Kbytes minimal requirement on i.MX8M PCIe outbound
> > region configuration.
> >
> > EP uses Bar0 to set the outboud region to configure the MSI setting.
> > Set the page_size to "epc_features->align" to meet the requirement,
> > let the MSI can be triggered successfully.
> >
> > Fixes: 1bd0d43dcf3b ("PCI: imx6: Clean up addr_space retrieval code")
> > Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx>
> > Reviewed-by: Frank Li <frank.li@xxxxxxx>
> > Acked-by: Jason Liu <jason.hui.liu@xxxxxxx>
> > ---
> >  drivers/pci/controller/dwc/pci-imx6.c | 5 +++++
> >  1 file changed, 5 insertions(+)
> >
> > diff --git a/drivers/pci/controller/dwc/pci-imx6.c
> > b/drivers/pci/controller/dwc/pci-imx6.c
> > index 99a60270b26c..3238b63721bc 100644
> > --- a/drivers/pci/controller/dwc/pci-imx6.c
> > +++ b/drivers/pci/controller/dwc/pci-imx6.c
> > @@ -1013,9 +1013,14 @@ static void imx6_pcie_ep_init(struct dw_pcie_ep
> > *ep)  {
> >  	enum pci_barno bar;
> >  	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> > +	const struct pci_epc_features *epc_features;
> >
> >  	for (bar = BAR_0; bar <= BAR_5; bar++)
> >  		dw_pcie_ep_reset_bar(pci, bar);
> > +	if (ep->ops->get_features) {
> > +		epc_features = ep->ops->get_features(ep);
> > +		ep->page_size = epc_features->align;
> > +	}
> 
> I suggest in imx6_add_pcie_ep()
> 
> 	ep->page_size = imx_pcie->drvdata->epc_features->aglgin;
> 
> 	it should be set before call dw_pcie_ep_init().
> 
> If you like, I can add this fixed to my patch serial to avoid conflict
> https://lore.kernel.org/linux-pci/Zfm720fz9NE0fD%2FP@lizhi-Precision-Tower-5
> 810/T/#t
> 
Thanks, I'm fine and glad about that.

Best Regards
Richard Zhu

> Frank
> 
> >  }
> >
> >  static int imx6_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
> > --
> > 2.37.1
> >