starfive: pci: Add StarFive JH7110 pcie driver

Add pcie driver for StarFive JH7110, Also add PLDA
PCIe controller common driver functions.

Several devices are tested:
a) M.2 NVMe SSD
b) Realtek 8169 Ethernet adapter.

Signed-off-by: Mason Huo <mason.huo@starfivetech.com>
Signed-off-by: Minda Chen <minda.chen@starfivetech.com>
Acked-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>
diff --git a/drivers/pci/pcie_plda_common.h b/drivers/pci/pcie_plda_common.h
new file mode 100644
index 0000000..409949f
--- /dev/null
+++ b/drivers/pci/pcie_plda_common.h
@@ -0,0 +1,118 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2023 StarFive Technology Co., Ltd.
+ * Author: Minda Chen <minda.chen@starfivetech.com>
+ *
+ */
+
+#ifndef PCIE_PLDA_COMMON_H
+#define PCIE_PLDA_COMMON_H
+
+#define GEN_SETTINGS			0x80
+#define PCIE_PCI_IDS			0x9C
+#define PCIE_WINROM			0xFC
+#define PMSG_SUPPORT_RX			0x3F0
+#define PCI_MISC			0xB4
+
+#define PLDA_EP_ENABLE			0
+#define PLDA_RP_ENABLE			1
+
+#define IDS_CLASS_CODE_SHIFT		8
+
+#define PREF_MEM_WIN_64_SUPPORT		BIT(3)
+#define PMSG_LTR_SUPPORT		BIT(2)
+#define PLDA_FUNCTION_DIS		BIT(15)
+#define PLDA_FUNC_NUM			4
+#define PLDA_PHY_FUNC_SHIFT		9
+
+#define XR3PCI_ATR_AXI4_SLV0		0x800
+#define XR3PCI_ATR_SRC_ADDR_LOW		0x0
+#define XR3PCI_ATR_SRC_ADDR_HIGH	0x4
+#define XR3PCI_ATR_TRSL_ADDR_LOW	0x8
+#define XR3PCI_ATR_TRSL_ADDR_HIGH	0xc
+#define XR3PCI_ATR_TRSL_PARAM		0x10
+#define XR3PCI_ATR_TABLE_OFFSET		0x20
+#define XR3PCI_ATR_MAX_TABLE_NUM	8
+
+#define XR3PCI_ATR_SRC_WIN_SIZE_SHIFT	1
+#define XR3PCI_ATR_SRC_ADDR_MASK	GENMASK(31, 12)
+#define XR3PCI_ATR_TRSL_ADDR_MASK	GENMASK(31, 12)
+#define XR3PCI_ATR_TRSL_DIR		BIT(22)
+/* IDs used in the XR3PCI_ATR_TRSL_PARAM */
+#define XR3PCI_ATR_TRSLID_PCIE_MEMORY	0x0
+#define XR3PCI_ATR_TRSLID_PCIE_CONFIG	0x1
+
+/**
+ * struct pcie_plda - PLDA PCIe controller state
+ *
+ * @reg_base: The base address of controller register space
+ * @cfg_base: The base address of configuration space
+ * @cfg_size: The size of configuration space
+ * @sec_busno: Secondary bus number.
+ * @atr_table_num: Total ATR table numbers.
+ */
+struct pcie_plda {
+	struct udevice	*dev;
+	void __iomem *reg_base;
+	void __iomem *cfg_base;
+	phys_size_t cfg_size;
+	int sec_busno;
+	int atr_table_num;
+};
+
+int plda_pcie_config_read(const struct udevice *udev, pci_dev_t bdf,
+			  uint offset, ulong *valuep,
+			  enum pci_size_t size);
+int plda_pcie_config_write(struct udevice *udev, pci_dev_t bdf,
+			   uint offset, ulong value,
+			   enum pci_size_t size);
+int plda_pcie_set_atr_entry(struct pcie_plda *plda, phys_addr_t src_addr,
+			    phys_addr_t trsl_addr, phys_size_t window_size,
+			    int trsl_param);
+
+static inline void plda_pcie_enable_root_port(struct pcie_plda *plda)
+{
+	u32 value;
+
+	value = readl(plda->reg_base + GEN_SETTINGS);
+	value |= PLDA_RP_ENABLE;
+	writel(value, plda->reg_base + GEN_SETTINGS);
+}
+
+static inline void plda_pcie_set_standard_class(struct pcie_plda *plda)
+{
+	u32 value;
+
+	value = readl(plda->reg_base + PCIE_PCI_IDS);
+	value &= 0xff;
+	value |= (PCI_CLASS_BRIDGE_PCI_NORMAL << IDS_CLASS_CODE_SHIFT);
+	writel(value, plda->reg_base + PCIE_PCI_IDS);
+}
+
+static inline void plda_pcie_set_pref_win_64bit(struct pcie_plda *plda)
+{
+	u32 value;
+
+	value = readl(plda->reg_base + PCIE_WINROM);
+	value |= PREF_MEM_WIN_64_SUPPORT;
+	writel(value, plda->reg_base + PCIE_WINROM);
+}
+
+static inline void plda_pcie_disable_ltr(struct pcie_plda *plda)
+{
+	u32 value;
+
+	value = readl(plda->reg_base + PMSG_SUPPORT_RX);
+	value &= ~PMSG_LTR_SUPPORT;
+	writel(value, plda->reg_base + PMSG_SUPPORT_RX);
+}
+
+static inline void plda_pcie_disable_func(struct pcie_plda *plda)
+{
+	u32 value;
+
+	value = readl(plda->reg_base + PCI_MISC);
+	value |= PLDA_FUNCTION_DIS;
+	writel(value, plda->reg_base + PCI_MISC);
+}
+#endif