diff mbox series

[v16,09/22] PCI: dwc: Add dw_pcie_link_set_max_link_width()

Message ID 20230510062234.201499-10-yoshihiro.shimoda.uh@renesas.com (mailing list archive)
State Superseded
Delegated to: Krzysztof Wilczyński
Headers show
Series PCI: rcar-gen4: Add R-Car Gen4 PCIe support | expand

Commit Message

Yoshihiro Shimoda May 10, 2023, 6:22 a.m. UTC 
To improve code readability, add dw_pcie_link_set_max_link_width().

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
---
 drivers/pci/controller/dwc/pcie-designware.c | 46 ++++++++++++--------
 1 file changed, 28 insertions(+), 18 deletions(-)
diff mbox series

Patch

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index a7c724ba7385..68aefbbcd68c 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -719,6 +719,33 @@  static void dw_pcie_link_set_max_speed(struct dw_pcie *pci, u32 link_gen)
 	dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, cap | link_speed);
 }
 
+static void dw_pcie_link_set_max_link_width(struct dw_pcie *pci, u32 num_lanes)
+{
+	u32 lwsc;
+
+	if (!num_lanes)
+		return;
+
+	/* Set link width speed control register */
+	lwsc = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
+	lwsc &= ~PORT_LOGIC_LINK_WIDTH_MASK;
+	switch (num_lanes) {
+	case 1:
+		lwsc |= PORT_LOGIC_LINK_WIDTH_1_LANES;
+		break;
+	case 2:
+		lwsc |= PORT_LOGIC_LINK_WIDTH_2_LANES;
+		break;
+	case 4:
+		lwsc |= PORT_LOGIC_LINK_WIDTH_4_LANES;
+		break;
+	case 8:
+		lwsc |= PORT_LOGIC_LINK_WIDTH_8_LANES;
+		break;
+	}
+	dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, lwsc);
+}
+
 void dw_pcie_iatu_detect(struct dw_pcie *pci)
 {
 	int max_region, ob, ib;
@@ -1026,22 +1053,5 @@  void dw_pcie_setup(struct dw_pcie *pci)
 	}
 	dw_pcie_writel_dbi(pci, PCIE_PORT_LINK_CONTROL, val);
 
-	/* Set link width speed control register */
-	val = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
-	val &= ~PORT_LOGIC_LINK_WIDTH_MASK;
-	switch (pci->num_lanes) {
-	case 1:
-		val |= PORT_LOGIC_LINK_WIDTH_1_LANES;
-		break;
-	case 2:
-		val |= PORT_LOGIC_LINK_WIDTH_2_LANES;
-		break;
-	case 4:
-		val |= PORT_LOGIC_LINK_WIDTH_4_LANES;
-		break;
-	case 8:
-		val |= PORT_LOGIC_LINK_WIDTH_8_LANES;
-		break;
-	}
-	dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, val);
+	dw_pcie_link_set_max_link_width(pci, pci->num_lanes);
 }