Merge branch 'lorenzo/pci/tegra'

- Fix Tegra OF node reference leak (Nishka Dasgupta)

  - Add #defines for PCIe Data Link Feature and Physical Layer 16.0 GT/s
    features (Vidya Sagar)

  - Disable MSI for Tegra Root Ports since they don't support using MSI for
    all Root Port events (Vidya Sagar)

  - Group DesignWare write-protected register writes together (Vidya Sagar)

  - Move DesignWare capability search interfaces so they can be used by
    both host and endpoint drivers (Vidya Sagar)

  - Add DesignWare extended capability search interfaces (Vidya Sagar)

  - Export dw_pcie_wait_for_link() so drivers can be modules (Vidya Sagar)

  - Add "snps,enable-cdm-check" DT binding for Configuration Dependent
    Module (CDM) register checking (Vidya Sagar)

  - Add DesignWare support for "snps,enable-cdm-check" CDM checking (Vidya
    Sagar)

  - Add "supports-clkreq" DT binding for host drivers to decide whether to
    advertise low power features (Vidya Sagar)

  - Add DT binding for Tegra194 (Vidya Sagar)

  - Add DT binding for Tegra194 P2U (PIPE to UPHY) block (Vidya Sagar)

  - Add support for Tegra194 P2U (PIPE to UPHY) (Vidya Sagar)

  - Add support for Tegra194 host controller (Vidya Sagar)

  - Add Tegra support for sideband PERST# and CLKREQ# for C5 (Vidya Sagar)

  - Add Tegra support for slot regulators for p2972-0000 platform (Vidya
    Sagar)

* lorenzo/pci/tegra:
  arm64: tegra: Add PCIe slot supply information in p2972-0000 platform
  arm64: tegra: Add configuration for PCIe C5 sideband signals
  PCI: tegra: Add support to enable slot regulators
  PCI: tegra: Add support to configure sideband pins
  dt-bindings: PCI: tegra: Add PCIe slot supplies regulator entries
  dt-bindings: PCI: tegra: Add sideband pins configuration entries
  PCI: tegra: Add Tegra194 PCIe support
  phy: tegra: Add PCIe PIPE2UPHY support
  dt-bindings: PHY: P2U: Add Tegra194 P2U block
  dt-bindings: PCI: tegra: Add device tree support for Tegra194
  dt-bindings: Add PCIe supports-clkreq property
  PCI: dwc: Add support to enable CDM register check
  dt-bindings: PCI: designware: Add binding for CDM register check
  PCI: dwc: Export dw_pcie_wait_for_link() API
  PCI: dwc: Add extended configuration space capability search API
  PCI: dwc: Move config space capability search API
  PCI: dwc: Group DBI registers writes requiring unlocking
  PCI: Disable MSI for Tegra root ports
  PCI: Add #defines for some of PCIe spec r4.0 features
  PCI: tegra: Fix OF node reference leak

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

@@ -14,6 +14,86 @@
 
 #include "pcie-designware.h"
 
+/*
+ * These interfaces resemble the pci_find_*capability() interfaces, but these
+ * are for configuring host controllers, which are bridges *to* PCI devices but
+ * are not PCI devices themselves.
+ */
+static u8 __dw_pcie_find_next_cap(struct dw_pcie *pci, u8 cap_ptr,
+				  u8 cap)
+{
+	u8 cap_id, next_cap_ptr;
+	u16 reg;
+
+	if (!cap_ptr)
+		return 0;
+
+	reg = dw_pcie_readw_dbi(pci, cap_ptr);
+	cap_id = (reg & 0x00ff);
+
+	if (cap_id > PCI_CAP_ID_MAX)
+		return 0;
+
+	if (cap_id == cap)
+		return cap_ptr;
+
+	next_cap_ptr = (reg & 0xff00) >> 8;
+	return __dw_pcie_find_next_cap(pci, next_cap_ptr, cap);
+}
+
+u8 dw_pcie_find_capability(struct dw_pcie *pci, u8 cap)
+{
+	u8 next_cap_ptr;
+	u16 reg;
+
+	reg = dw_pcie_readw_dbi(pci, PCI_CAPABILITY_LIST);
+	next_cap_ptr = (reg & 0x00ff);
+
+	return __dw_pcie_find_next_cap(pci, next_cap_ptr, cap);
+}
+EXPORT_SYMBOL_GPL(dw_pcie_find_capability);
+
+static u16 dw_pcie_find_next_ext_capability(struct dw_pcie *pci, u16 start,
+					    u8 cap)
+{
+	u32 header;
+	int ttl;
+	int pos = PCI_CFG_SPACE_SIZE;
+
+	/* minimum 8 bytes per capability */
+	ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
+
+	if (start)
+		pos = start;
+
+	header = dw_pcie_readl_dbi(pci, pos);
+	/*
+	 * If we have no capabilities, this is indicated by cap ID,
+	 * cap version and next pointer all being 0.
+	 */
+	if (header == 0)
+		return 0;
+
+	while (ttl-- > 0) {
+		if (PCI_EXT_CAP_ID(header) == cap && pos != start)
+			return pos;
+
+		pos = PCI_EXT_CAP_NEXT(header);
+		if (pos < PCI_CFG_SPACE_SIZE)
+			break;
+
+		header = dw_pcie_readl_dbi(pci, pos);
+	}
+
+	return 0;
+}
+
+u16 dw_pcie_find_ext_capability(struct dw_pcie *pci, u8 cap)
+{
+	return dw_pcie_find_next_ext_capability(pci, 0, cap);
+}
+EXPORT_SYMBOL_GPL(dw_pcie_find_ext_capability);
+
 int dw_pcie_read(void __iomem *addr, int size, u32 *val)
 {
 	if (!IS_ALIGNED((uintptr_t)addr, size)) {
@@ -376,10 +456,11 @@ int dw_pcie_wait_for_link(struct dw_pcie *pci)
 		usleep_range(LINK_WAIT_USLEEP_MIN, LINK_WAIT_USLEEP_MAX);
 	}
 
-	dev_err(pci->dev, "Phy link never came up\n");
+	dev_info(pci->dev, "Phy link never came up\n");
 
 	return -ETIMEDOUT;
 }
+EXPORT_SYMBOL_GPL(dw_pcie_wait_for_link);
 
 int dw_pcie_link_up(struct dw_pcie *pci)
 {
@@ -468,4 +549,11 @@ void dw_pcie_setup(struct dw_pcie *pci)
 		break;
 	}
 	dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, val);
+
+	if (of_property_read_bool(np, "snps,enable-cdm-check")) {
+		val = dw_pcie_readl_dbi(pci, PCIE_PL_CHK_REG_CONTROL_STATUS);
+		val |= PCIE_PL_CHK_REG_CHK_REG_CONTINUOUS |
+		       PCIE_PL_CHK_REG_CHK_REG_START;
+		dw_pcie_writel_dbi(pci, PCIE_PL_CHK_REG_CONTROL_STATUS, val);
+	}
 }