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In such cases, reinitializing the root complex is unnecessary if the DWC glue drivers wants to retain the PCIe link. Introduce a link_retain flag in struct dw_pcie_rp to indicate that the link should be preserved. When this flag is set by DWC glue drivers, skip dw_pcie_setup_rc() and only initialize MSI, avoiding redundant configuration steps. Signed-off-by: Krishna Chaitanya Chundru --- drivers/pci/controller/dwc/pcie-designware-host.c | 11 ++++++++--- drivers/pci/controller/dwc/pcie-designware.h | 1 + 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c index 372207c33a857b4c98572bb1e9b61fa0080bc871..d050df3f22e9507749a8f2fedd4c24fca43fb410 100644 --- a/drivers/pci/controller/dwc/pcie-designware-host.c +++ b/drivers/pci/controller/dwc/pcie-designware-host.c @@ -655,9 +655,14 @@ int dw_pcie_host_init(struct dw_pcie_rp *pp) if (ret) goto err_free_msi; - ret = dw_pcie_setup_rc(pp); - if (ret) - goto err_remove_edma; + if (!pp->link_retain) { + ret = dw_pcie_setup_rc(pp); + if (ret) + goto err_remove_edma; + } else { + dw_pcie_msi_init(pp); + } + if (!dw_pcie_link_up(pci)) { ret = dw_pcie_start_link(pci); diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h index 31685951a080456b8834aab2bf79a36c78f46639..8acab751b66a06e8322e027ab55dc0ecfdcf634c 100644 --- a/drivers/pci/controller/dwc/pcie-designware.h +++ b/drivers/pci/controller/dwc/pcie-designware.h @@ -439,6 +439,7 @@ struct dw_pcie_rp { struct pci_config_window *cfg; bool ecam_enabled; bool native_ecam; + bool link_retain; }; struct dw_pcie_ep_ops { -- 2.34.1