Hi Serge, On Sun, Dec 11, 2022 at 06:28:49PM +0300, Serge Semin wrote: > Hi Frank > > On Fri, Dec 09, 2022 at 03:52:42PM +0000, Frank Li wrote: > > Hi Serge, > > > > > From: Serge Semin, Sent: Thursday, December 8, 2022 11:01 PM > > > > > > Cc += Frank Li > > > > > > @Frank could you have a look at the thread and check the content of > > > the CSRs dbi+0x8f8 and dbi+0x978 on available to you DW PCIe +EDMA > > > devices? > > > > > [ 2.598038] imx6q-pcie 5f010000.pcie_ep: imx_add_pcie_ep: +0x8f8 = 3438302a, +0x978 = 00010001 > > Thanks for the reply. So it's 4.80a with the legacy viewport-based > access. Alas it isn't what we need in this thread. We'll need > @Mani's respond in order to decide how to fix the auto-detection > procedure. > Sorry for the late reply! With below diff on the EP: diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c index 6f3805228a18..0eb4d3218738 100644 --- a/drivers/pci/controller/dwc/pcie-designware.c +++ b/drivers/pci/controller/dwc/pcie-designware.c @@ -665,6 +665,10 @@ static int dw_pcie_edma_find_chip(struct dw_pcie *pci) if (val == 0xFFFFFFFF && pci->edma.reg_base) { pci->edma.mf = EDMA_MF_EDMA_UNROLL; + dev_info(pci->dev, "%s: +0x8f8 = %08x, +0x978 = %08x\n", __func__, + dw_pcie_readl_dbi(pci, 0x8f8), + dw_pcie_readl_dbi(pci, 0x978)); + val = dw_pcie_readl_dma(pci, PCIE_DMA_CTRL); } else if (val != 0xFFFFFFFF) { pci->edma.mf = EDMA_MF_EDMA_LEGACY; The output was: qcom-pcie-ep 1c08000.pcie-ep: dw_pcie_edma_find_chip: +0x8f8 = 3533302a, +0x978 = ffffffff Hope this helps! Thanks, Mani > -Serge(y) > > > > > Frank Li > > > > -- மணிவண்ணன் சதாசிவம்