usb: cdns3: Add Cadence USB3 DRD Driver

This patch introduce new Cadence USBSS DRD driver to Linux kernel.

The Cadence USBSS DRD Controller is a highly configurable IP Core which
can be instantiated as Dual-Role Device (DRD), Peripheral Only and
Host Only (XHCI)configurations.

The current driver has been validated with FPGA platform. We have
support for PCIe bus, which is used on FPGA prototyping.

The host side of USBSS-DRD controller is compliant with XHCI
specification, so it works with standard XHCI Linux driver.

Signed-off-by: Pawel Laszczak <[email protected]>
Signed-off-by: Felipe Balbi <[email protected]>

drivers/usb/Kconfig

@@ -114,6 +114,8 @@ source "drivers/usb/usbip/Kconfig"
 
 endif
 
+source "drivers/usb/cdns3/Kconfig"
+
 source "drivers/usb/mtu3/Kconfig"
 
 source "drivers/usb/musb/Kconfig"

drivers/usb/Makefile

@@ -13,6 +13,8 @@ obj-$(CONFIG_USB_DWC3)		+= dwc3/
 obj-$(CONFIG_USB_DWC2)		+= dwc2/
 obj-$(CONFIG_USB_ISP1760)	+= isp1760/
 
+obj-$(CONFIG_USB_CDNS3)		+= cdns3/
+
 obj-$(CONFIG_USB_MON)		+= mon/
 obj-$(CONFIG_USB_MTU3)		+= mtu3/
 

drivers/usb/cdns3/Kconfig

@@ -0,0 +1,46 @@
+config USB_CDNS3
+	tristate "Cadence USB3 Dual-Role Controller"
+	depends on USB_SUPPORT && (USB || USB_GADGET) && HAS_DMA
+	select USB_XHCI_PLATFORM if USB_XHCI_HCD
+	select USB_ROLE_SWITCH
+	help
+	  Say Y here if your system has a Cadence USB3 dual-role controller.
+	  It supports: dual-role switch, Host-only, and Peripheral-only.
+
+	  If you choose to build this driver is a dynamically linked
+	  as module, the module will be called cdns3.ko.
+
+if USB_CDNS3
+
+config USB_CDNS3_GADGET
+	bool "Cadence USB3 device controller"
+	depends on USB_GADGET=y || USB_GADGET=USB_CDNS3
+	help
+	  Say Y here to enable device controller functionality of the
+	  Cadence USBSS-DEV driver.
+
+	  This controller supports FF, HS and SS mode. It doesn't support
+	  LS and SSP mode.
+
+config USB_CDNS3_HOST
+	bool "Cadence USB3 host controller"
+	depends on USB=y || USB=USB_CDNS3
+	help
+	  Say Y here to enable host controller functionality of the
+	  Cadence driver.
+
+	  Host controller is compliant with XHCI so it will use
+	  standard XHCI driver.
+
+config USB_CDNS3_PCI_WRAP
+	tristate "Cadence USB3 support on PCIe-based platforms"
+	depends on USB_PCI && ACPI
+	default USB_CDNS3
+	help
+	  If you're using the USBSS Core IP with a PCIe, please say
+	  'Y' or 'M' here.
+
+	  If you choose to build this driver as module it will
+	  be dynamically linked and module will be called cdns3-pci.ko
+
+endif

drivers/usb/cdns3/Makefile

@@ -0,0 +1,16 @@
+# SPDX-License-Identifier: GPL-2.0
+# define_trace.h needs to know how to find our header
+CFLAGS_trace.o				:= -I$(src)
+
+cdns3-y					:= core.o drd.o
+
+obj-$(CONFIG_USB_CDNS3)			+= cdns3.o
+cdns3-$(CONFIG_USB_CDNS3_GADGET)	+= gadget.o ep0.o
+
+ifneq ($(CONFIG_USB_CDNS3_GADGET),)
+cdns3-$(CONFIG_TRACING)			+= trace.o
+endif
+
+cdns3-$(CONFIG_USB_CDNS3_HOST)		+= host.o
+
+obj-$(CONFIG_USB_CDNS3_PCI_WRAP)	+= cdns3-pci-wrap.o

drivers/usb/cdns3/cdns3-pci-wrap.c

@@ -0,0 +1,203 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence USBSS PCI Glue driver
+ *
+ * Copyright (C) 2018-2019 Cadence.
+ *
+ * Author: Pawel Laszczak <[email protected]>
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+
+struct cdns3_wrap {
+	struct platform_device *plat_dev;
+	struct resource dev_res[6];
+	int devfn;
+};
+
+#define RES_IRQ_HOST_ID		0
+#define RES_IRQ_PERIPHERAL_ID	1
+#define RES_IRQ_OTG_ID		2
+#define RES_HOST_ID		3
+#define RES_DEV_ID		4
+#define RES_DRD_ID		5
+
+#define PCI_BAR_HOST		0
+#define PCI_BAR_DEV		2
+#define PCI_BAR_OTG		0
+
+#define PCI_DEV_FN_HOST_DEVICE	0
+#define PCI_DEV_FN_OTG		1
+
+#define PCI_DRIVER_NAME		"cdns3-pci-usbss"
+#define PLAT_DRIVER_NAME	"cdns-usb3"
+
+#define CDNS_VENDOR_ID		0x17cd
+#define CDNS_DEVICE_ID		0x0100
+
+static struct pci_dev *cdns3_get_second_fun(struct pci_dev *pdev)
+{
+	struct pci_dev *func;
+
+	/*
+	 * Gets the second function.
+	 * It's little tricky, but this platform has two function.
+	 * The fist keeps resources for Host/Device while the second
+	 * keeps resources for DRD/OTG.
+	 */
+	func = pci_get_device(pdev->vendor, pdev->device, NULL);
+	if (unlikely(!func))
+		return NULL;
+
+	if (func->devfn == pdev->devfn) {
+		func = pci_get_device(pdev->vendor, pdev->device, func);
+		if (unlikely(!func))
+			return NULL;
+	}
+
+	return func;
+}
+
+static int cdns3_pci_probe(struct pci_dev *pdev,
+			   const struct pci_device_id *id)
+{
+	struct platform_device_info plat_info;
+	struct cdns3_wrap *wrap;
+	struct resource *res;
+	struct pci_dev *func;
+	int err;
+
+	/*
+	 * for GADGET/HOST PCI (devfn) function number is 0,
+	 * for OTG PCI (devfn) function number is 1
+	 */
+	if (!id || (pdev->devfn != PCI_DEV_FN_HOST_DEVICE &&
+		    pdev->devfn != PCI_DEV_FN_OTG))
+		return -EINVAL;
+
+	func = cdns3_get_second_fun(pdev);
+	if (unlikely(!func))
+		return -EINVAL;
+
+	err = pcim_enable_device(pdev);
+	if (err) {
+		dev_err(&pdev->dev, "Enabling PCI device has failed %d\n", err);
+		return err;
+	}
+
+	pci_set_master(pdev);
+
+	if (pci_is_enabled(func)) {
+		wrap = pci_get_drvdata(func);
+	} else {
+		wrap = kzalloc(sizeof(*wrap), GFP_KERNEL);
+		if (!wrap) {
+			pci_disable_device(pdev);
+			return -ENOMEM;
+		}
+	}
+
+	res = wrap->dev_res;
+
+	if (pdev->devfn == PCI_DEV_FN_HOST_DEVICE) {
+		/* function 0: host(BAR_0) + device(BAR_1).*/
+		dev_dbg(&pdev->dev, "Initialize Device resources\n");
+		res[RES_DEV_ID].start = pci_resource_start(pdev, PCI_BAR_DEV);
+		res[RES_DEV_ID].end =   pci_resource_end(pdev, PCI_BAR_DEV);
+		res[RES_DEV_ID].name = "dev";
+		res[RES_DEV_ID].flags = IORESOURCE_MEM;
+		dev_dbg(&pdev->dev, "USBSS-DEV physical base addr: %pa\n",
+			&res[RES_DEV_ID].start);
+
+		res[RES_HOST_ID].start = pci_resource_start(pdev, PCI_BAR_HOST);
+		res[RES_HOST_ID].end = pci_resource_end(pdev, PCI_BAR_HOST);
+		res[RES_HOST_ID].name = "xhci";
+		res[RES_HOST_ID].flags = IORESOURCE_MEM;
+		dev_dbg(&pdev->dev, "USBSS-XHCI physical base addr: %pa\n",
+			&res[RES_HOST_ID].start);
+
+		/* Interrupt for XHCI */
+		wrap->dev_res[RES_IRQ_HOST_ID].start = pdev->irq;
+		wrap->dev_res[RES_IRQ_HOST_ID].name = "host";
+		wrap->dev_res[RES_IRQ_HOST_ID].flags = IORESOURCE_IRQ;
+
+		/* Interrupt device. It's the same as for HOST. */
+		wrap->dev_res[RES_IRQ_PERIPHERAL_ID].start = pdev->irq;
+		wrap->dev_res[RES_IRQ_PERIPHERAL_ID].name = "peripheral";
+		wrap->dev_res[RES_IRQ_PERIPHERAL_ID].flags = IORESOURCE_IRQ;
+	} else {
+		res[RES_DRD_ID].start = pci_resource_start(pdev, PCI_BAR_OTG);
+		res[RES_DRD_ID].end =   pci_resource_end(pdev, PCI_BAR_OTG);
+		res[RES_DRD_ID].name = "otg";
+		res[RES_DRD_ID].flags = IORESOURCE_MEM;
+		dev_dbg(&pdev->dev, "USBSS-DRD physical base addr: %pa\n",
+			&res[RES_DRD_ID].start);
+
+		/* Interrupt for OTG/DRD. */
+		wrap->dev_res[RES_IRQ_OTG_ID].start = pdev->irq;
+		wrap->dev_res[RES_IRQ_OTG_ID].name = "otg";
+		wrap->dev_res[RES_IRQ_OTG_ID].flags = IORESOURCE_IRQ;
+	}
+
+	if (pci_is_enabled(func)) {
+		/* set up platform device info */
+		memset(&plat_info, 0, sizeof(plat_info));
+		plat_info.parent = &pdev->dev;
+		plat_info.fwnode = pdev->dev.fwnode;
+		plat_info.name = PLAT_DRIVER_NAME;
+		plat_info.id = pdev->devfn;
+		wrap->devfn  = pdev->devfn;
+		plat_info.res = wrap->dev_res;
+		plat_info.num_res = ARRAY_SIZE(wrap->dev_res);
+		plat_info.dma_mask = pdev->dma_mask;
+		/* register platform device */
+		wrap->plat_dev = platform_device_register_full(&plat_info);
+		if (IS_ERR(wrap->plat_dev)) {
+			pci_disable_device(pdev);
+			kfree(wrap);
+			return PTR_ERR(wrap->plat_dev);
+		}
+	}
+
+	pci_set_drvdata(pdev, wrap);
+	return err;
+}
+
+static void cdns3_pci_remove(struct pci_dev *pdev)
+{
+	struct cdns3_wrap *wrap;
+	struct pci_dev *func;
+
+	func = cdns3_get_second_fun(pdev);
+
+	wrap = (struct cdns3_wrap *)pci_get_drvdata(pdev);
+	if (wrap->devfn == pdev->devfn)
+		platform_device_unregister(wrap->plat_dev);
+
+	if (!pci_is_enabled(func))
+		kfree(wrap);
+}
+
+static const struct pci_device_id cdns3_pci_ids[] = {
+	{ PCI_DEVICE(CDNS_VENDOR_ID, CDNS_DEVICE_ID), },
+	{ 0, }
+};
+
+static struct pci_driver cdns3_pci_driver = {
+	.name = PCI_DRIVER_NAME,
+	.id_table = cdns3_pci_ids,
+	.probe = cdns3_pci_probe,
+	.remove = cdns3_pci_remove,
+};
+
+module_pci_driver(cdns3_pci_driver);
+MODULE_DEVICE_TABLE(pci, cdns3_pci_ids);
+
+MODULE_AUTHOR("Pawel Laszczak <[email protected]>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Cadence USBSS PCI wrapperr");