Merge branch 'pci/controller/dwc-qcom'

- Advertise 'Hot-Plug Capable' and set 'No Command Completed Support' since
  Qcom Root Ports support hotplug events like DL_Up/Down and can accept
  writes to Slot Control without delays between writes (Krishna Chaitanya
  Chundru)

* pci/controller/dwc-qcom:
  PCI: qcom: Advertise Hotplug Slot Capability with no Command Completion support

Author: bjorn-helgaas

drivers/pci/controller/dwc/pcie-qcom.c

@@ -350,15 +350,20 @@ static void qcom_pcie_clear_aspm_l0s(struct dw_pcie *pci)
 	dw_pcie_dbi_ro_wr_dis(pci);
 }
 
-static void qcom_pcie_clear_hpc(struct dw_pcie *pci)
+static void qcom_pcie_set_slot_nccs(struct dw_pcie *pci)
 {
 	u16 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
 	u32 val;
 
 	dw_pcie_dbi_ro_wr_en(pci);
 
+	/*
+	 * Qcom PCIe Root Ports do not support generating command completion
+	 * notifications for the Hot-Plug commands. So set the NCCS field to
+	 * avoid waiting for the completions.
+	 */
 	val = readl(pci->dbi_base + offset + PCI_EXP_SLTCAP);
-	val &= ~PCI_EXP_SLTCAP_HPC;
+	val |= PCI_EXP_SLTCAP_NCCS;
 	writel(val, pci->dbi_base + offset + PCI_EXP_SLTCAP);
 
 	dw_pcie_dbi_ro_wr_dis(pci);
@@ -558,7 +563,7 @@ static int qcom_pcie_post_init_2_1_0(struct qcom_pcie *pcie)
 	writel(CFG_BRIDGE_SB_INIT,
 	       pci->dbi_base + AXI_MSTR_RESP_COMP_CTRL1);
 
-	qcom_pcie_clear_hpc(pcie->pci);
+	qcom_pcie_set_slot_nccs(pcie->pci);
 
 	return 0;
 }
@@ -638,7 +643,7 @@ static int qcom_pcie_post_init_1_0_0(struct qcom_pcie *pcie)
 		writel(val, pcie->parf + PARF_AXI_MSTR_WR_ADDR_HALT);
 	}
 
-	qcom_pcie_clear_hpc(pcie->pci);
+	qcom_pcie_set_slot_nccs(pcie->pci);
 
 	return 0;
 }
@@ -731,7 +736,7 @@ static int qcom_pcie_post_init_2_3_2(struct qcom_pcie *pcie)
 	val |= EN;
 	writel(val, pcie->parf + PARF_AXI_MSTR_WR_ADDR_HALT_V2);
 
-	qcom_pcie_clear_hpc(pcie->pci);
+	qcom_pcie_set_slot_nccs(pcie->pci);
 
 	return 0;
 }
@@ -1037,7 +1042,7 @@ static int qcom_pcie_post_init_2_7_0(struct qcom_pcie *pcie)
 		writel(WR_NO_SNOOP_OVERRIDE_EN | RD_NO_SNOOP_OVERRIDE_EN,
 				pcie->parf + PARF_NO_SNOOP_OVERRIDE);
 
-	qcom_pcie_clear_hpc(pcie->pci);
+	qcom_pcie_set_slot_nccs(pcie->pci);
 
 	return 0;
 }