[PATCH v4 2/2] PCI: xilinx-xdma: Add Xilinx QDMA Root Port driver

[Thippeswamy Havalige]

Add support for Xilinx QDMA Soft IP core as Root Port.

The Versal Prime devices support QDMA soft IP module in programmable logic.

The integrated QDMA Soft IP block has integrated bridge function that can
act as PCIe Root Port.

Signed-off-by: Thippeswamy Havalige <thippesw@xxxxxxx>
---
 drivers/pci/controller/pcie-xilinx-dma-pl.c | 54 ++++++++++++++++++++-
 1 file changed, 53 insertions(+), 1 deletion(-)
---
changes in v4:
- none

changes in v3:
- Modify macro value to lower case.
- Change return type based QDMA compatible.

changes in v2:
- Add description for struct pl_dma_pcie
---
diff --git a/drivers/pci/controller/pcie-xilinx-dma-pl.c b/drivers/pci/controller/pcie-xilinx-dma-pl.c
index 5be5dfd8398f..1ea6a1d265bb 100644
--- a/drivers/pci/controller/pcie-xilinx-dma-pl.c
+++ b/drivers/pci/controller/pcie-xilinx-dma-pl.c
@@ -13,6 +13,7 @@
 #include <linux/msi.h>
 #include <linux/of_address.h>
 #include <linux/of_pci.h>
+#include <linux/of_platform.h>
 
 #include "../pci.h"
 #include "pcie-xilinx-common.h"
@@ -71,10 +72,24 @@
 
 /* Phy Status/Control Register definitions */
 #define XILINX_PCIE_DMA_REG_PSCR_LNKUP	BIT(11)
+#define QDMA_BRIDGE_BASE_OFF		0xcd8
 
 /* Number of MSI IRQs */
 #define XILINX_NUM_MSI_IRQS	64
 
+enum xilinx_pl_dma_version {
+	XDMA,
+	QDMA,
+};
+
+/**
+ * struct xilinx_pl_dma_variant - PL DMA PCIe variant information
+ * @version: DMA version
+ */
+struct xilinx_pl_dma_variant {
+	enum xilinx_pl_dma_version version;
+};
+
 struct xilinx_msi {
 	struct irq_domain	*msi_domain;
 	unsigned long		*bitmap;
@@ -88,6 +103,7 @@ struct xilinx_msi {
  * struct pl_dma_pcie - PCIe port information
  * @dev: Device pointer
  * @reg_base: IO Mapped Register Base
+ * @cfg_base: IO Mapped Configuration Base
  * @irq: Interrupt number
  * @cfg: Holds mappings of config space window
  * @phys_reg_base: Physical address of reg base
@@ -97,10 +113,12 @@ struct xilinx_msi {
  * @msi: MSI information
  * @intx_irq: INTx error interrupt number
  * @lock: Lock protecting shared register access
+ * @variant: PL DMA PCIe version check pointer
  */
 struct pl_dma_pcie {
 	struct device			*dev;
 	void __iomem			*reg_base;
+	void __iomem			*cfg_base;
 	int				irq;
 	struct pci_config_window	*cfg;
 	phys_addr_t			phys_reg_base;
@@ -110,16 +128,23 @@ struct pl_dma_pcie {
 	struct xilinx_msi		msi;
 	int				intx_irq;
 	raw_spinlock_t			lock;
+	const struct xilinx_pl_dma_variant   *variant;
 };
 
 static inline u32 pcie_read(struct pl_dma_pcie *port, u32 reg)
 {
+	if (port->variant->version == QDMA)
+		return readl(port->reg_base + reg + QDMA_BRIDGE_BASE_OFF);
+
 	return readl(port->reg_base + reg);
 }
 
 static inline void pcie_write(struct pl_dma_pcie *port, u32 val, u32 reg)
 {
-	writel(val, port->reg_base + reg);
+	if (port->variant->version == QDMA)
+		writel(val, port->reg_base + reg + QDMA_BRIDGE_BASE_OFF);
+	else
+		writel(val, port->reg_base + reg);
 }
 
 static inline bool xilinx_pl_dma_pcie_link_up(struct pl_dma_pcie *port)
@@ -173,6 +198,9 @@ static void __iomem *xilinx_pl_dma_pcie_map_bus(struct pci_bus *bus,
 	if (!xilinx_pl_dma_pcie_valid_device(bus, devfn))
 		return NULL;
 
+	if (port->variant->version == QDMA)
+		return port->cfg_base + PCIE_ECAM_OFFSET(bus->number, devfn, where);
+
 	return port->reg_base + PCIE_ECAM_OFFSET(bus->number, devfn, where);
 }
 
@@ -731,6 +759,15 @@ static int xilinx_pl_dma_pcie_parse_dt(struct pl_dma_pcie *port,
 
 	port->reg_base = port->cfg->win;
 
+	if (port->variant->version == QDMA) {
+		port->cfg_base = port->cfg->win;
+		res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "breg");
+		port->reg_base = devm_ioremap_resource(dev, res);
+		if (IS_ERR(port->reg_base))
+			return PTR_ERR(port->reg_base);
+		port->phys_reg_base = res->start;
+	}
+
 	err = xilinx_request_msi_irq(port);
 	if (err) {
 		pci_ecam_free(port->cfg);
@@ -760,6 +797,8 @@ static int xilinx_pl_dma_pcie_probe(struct platform_device *pdev)
 	if (!bus)
 		return -ENODEV;
 
+	port->variant = of_device_get_match_data(dev);
+
 	err = xilinx_pl_dma_pcie_parse_dt(port, bus->res);
 	if (err) {
 		dev_err(dev, "Parsing DT failed\n");
@@ -791,9 +830,22 @@ static int xilinx_pl_dma_pcie_probe(struct platform_device *pdev)
 	return err;
 }
 
+static const struct xilinx_pl_dma_variant xdma_host = {
+	.version = XDMA,
+};
+
+static const struct xilinx_pl_dma_variant qdma_host = {
+	.version = QDMA,
+};
+
 static const struct of_device_id xilinx_pl_dma_pcie_of_match[] = {
 	{
 		.compatible = "xlnx,xdma-host-3.00",
+		.data = &xdma_host,
+	},
+	{
+		.compatible = "xlnx,qdma-host-3.00",
+		.data = &qdma_host,
 	},
 	{}
 };
-- 
2.34.1