PCI_PTM_CAP
reg = dw_pcie_readl_dbi(pci, ptm_cap_base + PCI_PTM_CAP);
dw_pcie_writel_dbi(pci, ptm_cap_base + PCI_PTM_CAP, reg);
reg = dw_pcie_readl_dbi(pci, ptm_cap_base + PCI_PTM_CAP);
dw_pcie_writel_dbi(pci, ptm_cap_base + PCI_PTM_CAP, reg);
pci_read_config_dword(dev, ptm + PCI_PTM_CAP, &cap);