Hi, On 25.01.2021 05:48, Zhiqiang Hou wrote: > From: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx> > > In the dw_pcie_ep_init(), it depends on the detected iATU region > numbers to allocate the in/outbound window management bit map. > It fails after the commit 281f1f99cf3a ("PCI: dwc: Detect number > of iATU windows"). > > So this patch move the iATU region detection into a new function, > move forward the detection to the very beginning of functions > dw_pcie_host_init() and dw_pcie_ep_init(). And also remove it > from the dw_pcie_setup(), since it's more like a software > perspective initialization step than hardware setup. > > Fixes: 281f1f99cf3a ("PCI: dwc: Detect number of iATU windows") > Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx> This patch causes exynos-pcie to hang during the initialization. It looks that some resources are not enabled yet, so calling dw_pcie_iatu_detect() much earlier causes a hang. When I have some time, I will try to identify what is needed to call it properly. > --- > drivers/pci/controller/dwc/pcie-designware-ep.c | 2 ++ > drivers/pci/controller/dwc/pcie-designware-host.c | 2 ++ > drivers/pci/controller/dwc/pcie-designware.c | 11 ++++++++--- > drivers/pci/controller/dwc/pcie-designware.h | 1 + > 4 files changed, 13 insertions(+), 3 deletions(-) > > diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c > index bcd1cd9ba8c8..fcf935bf6f5e 100644 > --- a/drivers/pci/controller/dwc/pcie-designware-ep.c > +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c > @@ -707,6 +707,8 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep) > } > } > > + dw_pcie_iatu_detect(pci); > + > res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "addr_space"); > if (!res) > return -EINVAL; > diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c > index 8a84c005f32b..8eae817c138d 100644 > --- a/drivers/pci/controller/dwc/pcie-designware-host.c > +++ b/drivers/pci/controller/dwc/pcie-designware-host.c > @@ -316,6 +316,8 @@ int dw_pcie_host_init(struct pcie_port *pp) > return PTR_ERR(pci->dbi_base); > } > > + dw_pcie_iatu_detect(pci); > + > bridge = devm_pci_alloc_host_bridge(dev, 0); > if (!bridge) > return -ENOMEM; > diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c > index 5b72a5448d2e..5b9bf02d918b 100644 > --- a/drivers/pci/controller/dwc/pcie-designware.c > +++ b/drivers/pci/controller/dwc/pcie-designware.c > @@ -654,11 +654,9 @@ static void dw_pcie_iatu_detect_regions(struct dw_pcie *pci) > pci->num_ob_windows = ob; > } > > -void dw_pcie_setup(struct dw_pcie *pci) > +void dw_pcie_iatu_detect(struct dw_pcie *pci) > { > - u32 val; > struct device *dev = pci->dev; > - struct device_node *np = dev->of_node; > struct platform_device *pdev = to_platform_device(dev); > > if (pci->version >= 0x480A || (!pci->version && > @@ -687,6 +685,13 @@ void dw_pcie_setup(struct dw_pcie *pci) > > dev_info(pci->dev, "Detected iATU regions: %u outbound, %u inbound", > pci->num_ob_windows, pci->num_ib_windows); > +} > + > +void dw_pcie_setup(struct dw_pcie *pci) > +{ > + u32 val; > + struct device *dev = pci->dev; > + struct device_node *np = dev->of_node; > > if (pci->link_gen > 0) > dw_pcie_link_set_max_speed(pci, pci->link_gen); > diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h > index 5d979953800d..867369d4c4f7 100644 > --- a/drivers/pci/controller/dwc/pcie-designware.h > +++ b/drivers/pci/controller/dwc/pcie-designware.h > @@ -305,6 +305,7 @@ int dw_pcie_prog_inbound_atu(struct dw_pcie *pci, u8 func_no, int index, > void dw_pcie_disable_atu(struct dw_pcie *pci, int index, > enum dw_pcie_region_type type); > void dw_pcie_setup(struct dw_pcie *pci); > +void dw_pcie_iatu_detect(struct dw_pcie *pci); > > static inline void dw_pcie_writel_dbi(struct dw_pcie *pci, u32 reg, u32 val) > { Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland