[PATCH v17 08/20] PCI: dwc: Add dw_pcie_link_set_max_link_width()

[Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>]

To improve code readability, add dw_pcie_link_set_max_link_width().

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <mani@xxxxxxxxxx>
---
 drivers/pci/controller/dwc/pcie-designware.c | 86 ++++++++++----------
 1 file changed, 41 insertions(+), 45 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index a531dc50abea..7b720bad7656 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -728,6 +728,46 @@ static void dw_pcie_link_set_max_speed(struct dw_pcie *pci, u32 link_gen)
 
 }
 
+static void dw_pcie_link_set_max_link_width(struct dw_pcie *pci, u32 num_lanes)
+{
+	u32 lwsc, plc;
+
+	if (!num_lanes)
+		return;
+
+	/* Set the number of lanes */
+	plc = dw_pcie_readl_dbi(pci, PCIE_PORT_LINK_CONTROL);
+	plc &= ~PORT_LINK_FAST_LINK_MODE;
+	plc &= ~PORT_LINK_MODE_MASK;
+
+	/* 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:
+		plc |= PORT_LINK_MODE_1_LANES;
+		lwsc |= PORT_LOGIC_LINK_WIDTH_1_LANES;
+		break;
+	case 2:
+		plc |= PORT_LINK_MODE_2_LANES;
+		lwsc |= PORT_LOGIC_LINK_WIDTH_2_LANES;
+		break;
+	case 4:
+		plc |= PORT_LINK_MODE_4_LANES;
+		lwsc |= PORT_LOGIC_LINK_WIDTH_4_LANES;
+		break;
+	case 8:
+		plc |= PORT_LINK_MODE_8_LANES;
+		lwsc |= PORT_LOGIC_LINK_WIDTH_8_LANES;
+		break;
+	default:
+		dev_err(pci->dev, "num-lanes %u: invalid value\n", num_lanes);
+		return;
+	}
+	dw_pcie_writel_dbi(pci, PCIE_PORT_LINK_CONTROL, plc);
+	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;
@@ -1009,49 +1049,5 @@ void dw_pcie_setup(struct dw_pcie *pci)
 	val |= PORT_LINK_DLL_LINK_EN;
 	dw_pcie_writel_dbi(pci, PCIE_PORT_LINK_CONTROL, val);
 
-	if (!pci->num_lanes) {
-		dev_dbg(pci->dev, "Using h/w default number of lanes\n");
-		return;
-	}
-
-	/* Set the number of lanes */
-	val &= ~PORT_LINK_FAST_LINK_MODE;
-	val &= ~PORT_LINK_MODE_MASK;
-	switch (pci->num_lanes) {
-	case 1:
-		val |= PORT_LINK_MODE_1_LANES;
-		break;
-	case 2:
-		val |= PORT_LINK_MODE_2_LANES;
-		break;
-	case 4:
-		val |= PORT_LINK_MODE_4_LANES;
-		break;
-	case 8:
-		val |= PORT_LINK_MODE_8_LANES;
-		break;
-	default:
-		dev_err(pci->dev, "num-lanes %u: invalid value\n", pci->num_lanes);
-		return;
-	}
-	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);
 }
-- 
2.25.1