PCI: dwc: Implement .assert_perst() for dwc glue drivers

Add .assert_perst() hook for dwc glue drivers to register with
assert_perst() of pci ops, allowing for better control over the link
initialization and shutdown process.

Implement assert_perst() function op for dwc drivers.

Signed-off-by: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>
[bhelgaas: squash dwc host support]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://patch.msgid.link/20251101-tc9563-v9-3-de3429f7787a@oss.qualcomm.com
Link: https://patch.msgid.link/20251101-tc9563-v9-4-de3429f7787a@oss.qualcomm.com

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 20c9333bcb1c4812e2fd96047a49944574df1e6f..b56dd1d51fa4f03931942dc9da649bef8859f192 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -842,10 +842,19 @@ void __iomem *dw_pcie_own_conf_map_bus(struct pci_bus *bus, unsigned int devfn,
 }
 EXPORT_SYMBOL_GPL(dw_pcie_own_conf_map_bus);
 
+static int dw_pcie_op_assert_perst(struct pci_bus *bus, bool assert)
+{
+       struct dw_pcie_rp *pp = bus->sysdata;
+       struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+
+       return dw_pcie_assert_perst(pci, assert);
+}
+
 static struct pci_ops dw_pcie_ops = {
        .map_bus = dw_pcie_own_conf_map_bus,
        .read = pci_generic_config_read,
        .write = pci_generic_config_write,
+       .assert_perst = dw_pcie_op_assert_perst,
 };
 
 static int dw_pcie_iatu_setup(struct dw_pcie_rp *pp)

diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index e995f692a1ecd10130d3be3358827f801811387f..99a02f052e1c8410573ecd44340a9ba4f822e979 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -485,6 +485,7 @@ struct dw_pcie_ops {
        enum dw_pcie_ltssm (*get_ltssm)(struct dw_pcie *pcie);
        int     (*start_link)(struct dw_pcie *pcie);
        void    (*stop_link)(struct dw_pcie *pcie);
+       int     (*assert_perst)(struct dw_pcie *pcie, bool assert);
 };
 
 struct debugfs_info {
@@ -787,6 +788,14 @@ static inline void dw_pcie_stop_link(struct dw_pcie *pci)
                pci->ops->stop_link(pci);
 }
 
+static inline int dw_pcie_assert_perst(struct dw_pcie *pci, bool assert)
+{
+       if (pci->ops && pci->ops->assert_perst)
+               return pci->ops->assert_perst(pci, assert);
+
+       return 0;
+}
+
 static inline enum dw_pcie_ltssm dw_pcie_get_ltssm(struct dw_pcie *pci)
 {
        u32 val;