[PATCH v6 16/37] drivers: usb: Add generic XHCI

[Patrick Rudolph <patrick.rudolph@9elements.com>]

Add support for the generic XHCI driver that contains no SoC
specific code. It can be used on platforms that simply work out
of the box, like on emulated platforms.

TEST: Booted on QEMU sbsa machine using the generic xhci driver.

Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Cc: Tom Rini <trini@konsulko.com>
Cc: Marek Vasut <marex@denx.de>
---
Changelog v3:
- Drop weak board_xhci_enable()
Changelog v4:
- Use dev_dbg() instead of debug()
Changelog v6:
- Update header order

---
 drivers/usb/host/Kconfig        |  8 ++++
 drivers/usb/host/Makefile       |  1 +
 drivers/usb/host/xhci-generic.c | 75 +++++++++++++++++++++++++++++++++
 3 files changed, 84 insertions(+)
 create mode 100644 drivers/usb/host/xhci-generic.c

diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index 6e10b629a3..bb5893d56d 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -68,6 +68,14 @@ config USB_XHCI_MVEBU
 	  SoCs, which includes Armada8K, Armada3700 and other Armada
 	  family SoCs.
 
+config USB_XHCI_GENERIC
+	bool "Generic SoC USB 3.0 support"
+	depends on OF_CONTROL
+	default n
+	help
+	  Choose this option to add support for USB 3.0 driver for SoCs
+	  that do not need platform specific code, like on emulated targets.
+
 config USB_XHCI_OCTEON
 	bool "Support for Marvell Octeon family on-chip xHCI USB controller"
 	depends on ARCH_OCTEON
diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile
index 8dad36f936..9e880195ec 100644
--- a/drivers/usb/host/Makefile
+++ b/drivers/usb/host/Makefile
@@ -50,6 +50,7 @@ obj-$(CONFIG_USB_XHCI_EXYNOS) += xhci-exynos5.o
 obj-$(CONFIG_USB_XHCI_FSL) += xhci-fsl.o
 obj-$(CONFIG_USB_XHCI_MTK) += xhci-mtk.o
 obj-$(CONFIG_USB_XHCI_MVEBU) += xhci-mvebu.o
+obj-$(CONFIG_USB_XHCI_GENERIC) += xhci-generic.o
 obj-$(CONFIG_USB_XHCI_OMAP) += xhci-omap.o
 obj-$(CONFIG_USB_XHCI_PCI) += xhci-pci.o
 obj-$(CONFIG_USB_XHCI_RCAR) += xhci-rcar.o
diff --git a/drivers/usb/host/xhci-generic.c b/drivers/usb/host/xhci-generic.c
new file mode 100644
index 0000000000..355d488317
--- /dev/null
+++ b/drivers/usb/host/xhci-generic.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2024 9elements GmbH
+ *
+ * GENERIC USB HOST xHCI Controller
+ */
+#include <dm.h>
+#include <fdtdec.h>
+#include <log.h>
+#include <usb.h>
+#include <asm/io.h>
+#include <dm/device_compat.h>
+#include <usb/xhci.h>
+
+struct generic_xhci_plat {
+	fdt_addr_t hcd_base;
+};
+
+/**
+ * Contains pointers to register base addresses
+ * for the usb controller.
+ */
+struct generic_xhci {
+	struct xhci_ctrl ctrl;	/* Needs to come first in this struct! */
+	struct usb_plat usb_plat;
+	struct xhci_hccr *hcd;
+};
+
+static int xhci_usb_probe(struct udevice *dev)
+{
+	struct generic_xhci_plat *plat = dev_get_plat(dev);
+	struct generic_xhci *ctx = dev_get_priv(dev);
+	struct xhci_hcor *hcor;
+	int len;
+
+	ctx->hcd = (struct xhci_hccr *)phys_to_virt(plat->hcd_base);
+	len = HC_LENGTH(xhci_readl(&ctx->hcd->cr_capbase));
+	hcor = (struct xhci_hcor *)((uintptr_t)ctx->hcd + len);
+
+	return xhci_register(dev, ctx->hcd, hcor);
+}
+
+static int xhci_usb_of_to_plat(struct udevice *dev)
+{
+	struct generic_xhci_plat *plat = dev_get_plat(dev);
+
+	/*
+	 * Get the base address for XHCI controller from the device node
+	 */
+	plat->hcd_base = dev_read_addr(dev);
+	if (plat->hcd_base == FDT_ADDR_T_NONE) {
+		dev_dbg(dev, "Can't get the XHCI register base address\n");
+		return -ENXIO;
+	}
+
+	return 0;
+}
+
+static const struct udevice_id xhci_usb_ids[] = {
+	{ .compatible = "generic-xhci" },
+	{ }
+};
+
+U_BOOT_DRIVER(usb_xhci) = {
+	.name	= "xhci_generic",
+	.id	= UCLASS_USB,
+	.of_match = xhci_usb_ids,
+	.of_to_plat = xhci_usb_of_to_plat,
+	.probe = xhci_usb_probe,
+	.remove = xhci_deregister,
+	.ops	= &xhci_usb_ops,
+	.plat_auto	= sizeof(struct generic_xhci_plat),
+	.priv_auto	= sizeof(struct generic_xhci),
+	.flags	= DM_FLAG_ALLOC_PRIV_DMA,
+};
-- 
2.46.2