On Sat, Apr 27, 2024 at 02:53:03PM +0530, Manivannan Sadhasivam wrote:
> On Tue, Apr 02, 2024 at 10:33:38AM -0400, Frank Li wrote:
> > From: Richard Zhu <hongxing.zhu@xxxxxxx>
> >
> > 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.
>
> I don't understand this statement. How EP can use BAR0 for MSI? MSIs are
> triggered using outbound window memory while BARs are mapped as inbound.
>
> - Mani
Let's rewrite commit message.
PCI: imx6: Fix i.MX8MP PCIe EP's occasional failure to trigger MSI
i.MX8MP PCIe EP requires 64KB alignment. MSI triggering may fail if the
outbound MSI memory region (ep->msi_mem) is not aligned to 64KB.
In dw_pcie_ep_init():
ep->msi_mem = pci_epc_mem_alloc_addr(epc, &ep->msi_mem_phys,
epc->mem->window.page_size);
Set ep->page_size to match drvdata::epc_features::align since different
SOCs have different alignment requirements.
Frank
>
> > 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>
> > Acked-by: Jason Liu <jason.hui.liu@xxxxxxx>
> > Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
> > ---
> > drivers/pci/controller/dwc/pci-imx6.c | 2 ++
> > 1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> > index e43eda6b33ca7..6c4d25b92225e 100644
> > --- a/drivers/pci/controller/dwc/pci-imx6.c
> > +++ b/drivers/pci/controller/dwc/pci-imx6.c
> > @@ -1118,6 +1118,8 @@ static int imx6_add_pcie_ep(struct imx6_pcie *imx6_pcie,
> > if (imx6_check_flag(imx6_pcie, IMX6_PCIE_FLAG_SUPPORT_64BIT))
> > dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
> >
> > + ep->page_size = imx6_pcie->drvdata->epc_features->align;
> > +
> > ret = dw_pcie_ep_init(ep);
> > if (ret) {
> > dev_err(dev, "failed to initialize endpoint\n");
> >
> > --
> > 2.34.1
> >
>
> --
> மணிவண்ணன் சதாசிவம்
