PCI: dwc: intel: PCIe RC controller driver

Add support to PCIe RC controller on Intel Gateway SoCs.
PCIe controller is based of Synopsys DesignWare PCIe core.

Intel PCIe driver requires Upconfigure support, Fast Training
Sequence and link speed configurations. So adding the respective
helper functions in the PCIe DesignWare framework.
It also programs hardware autonomous speed during speed
configuration so defining it in pci_regs.h.

Also, mark Intel PCIe driver depends on MSI IRQ Domain
as Synopsys DesignWare framework depends on the
PCI_MSI_IRQ_DOMAIN.

Signed-off-by: Dilip Kota <eswara.kota@linux.intel.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Andrew Murray <andrew.murray@arm.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Acked-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>

1 files changed, 56 insertions, 0 deletions

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index 820488dfeaed..681548c88282 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -12,6 +12,7 @@
 #include <linux/of.h>
 #include <linux/types.h>
 
+#include "../../pci.h"
 #include "pcie-designware.h"
 
 /*
@@ -474,6 +475,61 @@ int dw_pcie_link_up(struct dw_pcie *pci)
 		(!(val & PCIE_PORT_DEBUG1_LINK_IN_TRAINING)));
 }
 
+void dw_pcie_upconfig_setup(struct dw_pcie *pci)
+{
+	u32 val;
+
+	val = dw_pcie_readl_dbi(pci, PCIE_PORT_MULTI_LANE_CTRL);
+	val |= PORT_MLTI_UPCFG_SUPPORT;
+	dw_pcie_writel_dbi(pci, PCIE_PORT_MULTI_LANE_CTRL, val);
+}
+EXPORT_SYMBOL_GPL(dw_pcie_upconfig_setup);
+
+void dw_pcie_link_set_max_speed(struct dw_pcie *pci, u32 link_gen)
+{
+	u32 reg, val;
+	u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
+
+	reg = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCTL2);
+	reg &= ~PCI_EXP_LNKCTL2_TLS;
+
+	switch (pcie_link_speed[link_gen]) {
+	case PCIE_SPEED_2_5GT:
+		reg |= PCI_EXP_LNKCTL2_TLS_2_5GT;
+		break;
+	case PCIE_SPEED_5_0GT:
+		reg |= PCI_EXP_LNKCTL2_TLS_5_0GT;
+		break;
+	case PCIE_SPEED_8_0GT:
+		reg |= PCI_EXP_LNKCTL2_TLS_8_0GT;
+		break;
+	case PCIE_SPEED_16_0GT:
+		reg |= PCI_EXP_LNKCTL2_TLS_16_0GT;
+		break;
+	default:
+		/* Use hardware capability */
+		val = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
+		val = FIELD_GET(PCI_EXP_LNKCAP_SLS, val);
+		reg &= ~PCI_EXP_LNKCTL2_HASD;
+		reg |= FIELD_PREP(PCI_EXP_LNKCTL2_TLS, val);
+		break;
+	}
+
+	dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCTL2, reg);
+}
+EXPORT_SYMBOL_GPL(dw_pcie_link_set_max_speed);
+
+void dw_pcie_link_set_n_fts(struct dw_pcie *pci, u32 n_fts)
+{
+	u32 val;
+
+	val = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
+	val &= ~PORT_LOGIC_N_FTS_MASK;
+	val |= n_fts & PORT_LOGIC_N_FTS_MASK;
+	dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, val);
+}
+EXPORT_SYMBOL_GPL(dw_pcie_link_set_n_fts);
+
 static u8 dw_pcie_iatu_unroll_enabled(struct dw_pcie *pci)
 {
 	u32 val;