omarchy-pkgs/pkgbuilds/linux-omarchy-eevdf/0601-thunderbolt-updates.patch

diff --git a/drivers/net/thunderbolt/main.c b/drivers/net/thunderbolt/main.c
--- a/drivers/net/thunderbolt/main.c
+++ b/drivers/net/thunderbolt/main.c
@@ -1362,7 +1362,7 @@ static void tbnet_generate_mac(struct net_device *dev)
 	dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
 }
 
-static int tbnet_probe(struct tb_service *svc, const struct tb_service_id *id)
+static int tbnet_probe(struct tb_service *svc)
 {
 	struct tb_xdomain *xd = tb_service_parent(svc);
 	struct net_device *dev;
@@ -1482,7 +1482,7 @@ static DEFINE_SIMPLE_DEV_PM_OPS(tbnet_pm_ops, tbnet_suspend, tbnet_resume);
 
 static const struct tb_service_id tbnet_ids[] = {
 	{ TB_SERVICE("network", 1) },
-	{ },
+	{ }
 };
 MODULE_DEVICE_TABLE(tbsvc, tbnet_ids);
 
diff --git a/drivers/thunderbolt/debugfs.c b/drivers/thunderbolt/debugfs.c
--- a/drivers/thunderbolt/debugfs.c
+++ b/drivers/thunderbolt/debugfs.c
@@ -136,13 +136,13 @@ static void *validate_and_copy_from_user(const void __user *user_buf,
 	if (!access_ok(user_buf, *count))
 		return ERR_PTR(-EFAULT);
 
-	buf = (void *)get_zeroed_page(GFP_KERNEL);
+	buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
 	if (!buf)
 		return ERR_PTR(-ENOMEM);
 
 	nbytes = min_t(size_t, *count, PAGE_SIZE);
 	if (copy_from_user(buf, user_buf, nbytes)) {
-		free_page((unsigned long)buf);
+		kfree(buf);
 		return ERR_PTR(-EFAULT);
 	}
 
@@ -265,7 +265,7 @@ static ssize_t regs_write(struct tb_switch *sw, struct tb_port *port,
 out:
 	pm_runtime_mark_last_busy(&sw->dev);
 	pm_runtime_put_autosuspend(&sw->dev);
-	free_page((unsigned long)buf);
+	kfree(buf);
 
 	return ret < 0 ? ret : count;
 }
@@ -406,7 +406,7 @@ static ssize_t port_sb_regs_write(struct file *file, const char __user *user_buf
 out:
 	pm_runtime_mark_last_busy(&sw->dev);
 	pm_runtime_put_autosuspend(&sw->dev);
-	free_page((unsigned long)buf);
+	kfree(buf);
 
 	return ret < 0 ? ret : count;
 }
@@ -439,7 +439,7 @@ static ssize_t retimer_sb_regs_write(struct file *file,
 out:
 	pm_runtime_mark_last_busy(&rt->dev);
 	pm_runtime_put_autosuspend(&rt->dev);
-	free_page((unsigned long)buf);
+	kfree(buf);
 
 	return ret < 0 ? ret : count;
 }
@@ -652,7 +652,7 @@ margining_ber_level_write(struct file *file, const char __user *user_buf,
 	margining->ber_level = val;
 
 out_free:
-	free_page((unsigned long)buf);
+	kfree(buf);
 out_unlock:
 	mutex_unlock(&tb->lock);
 
@@ -829,7 +829,7 @@ margining_lanes_write(struct file *file, const char __user *user_buf,
 		}
 	}
 
-	free_page((unsigned long)buf);
+	kfree(buf);
 
 	if (lane == -1)
 		return -EINVAL;
@@ -958,7 +958,7 @@ margining_error_counter_write(struct file *file, const char __user *user_buf,
 	else
 		goto err_free;
 
-	free_page((unsigned long)buf);
+	kfree(buf);
 
 	scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &tb->lock) {
 		if (!margining->software)
@@ -970,7 +970,7 @@ margining_error_counter_write(struct file *file, const char __user *user_buf,
 	return count;
 
 err_free:
-	free_page((unsigned long)buf);
+	kfree(buf);
 	return -EINVAL;
 }
 
@@ -1116,7 +1116,7 @@ static ssize_t margining_mode_write(struct file *file,
 	mutex_unlock(&tb->lock);
 
 out_free:
-	free_page((unsigned long)buf);
+	kfree(buf);
 	return ret ? ret : count;
 }
 
@@ -1503,7 +1503,7 @@ static ssize_t margining_test_write(struct file *file,
 	mutex_unlock(&tb->lock);
 
 out_free:
-	free_page((unsigned long)buf);
+	kfree(buf);
 	return ret ? ret : count;
 }
 
@@ -1569,7 +1569,7 @@ static ssize_t margining_margin_write(struct file *file,
 	mutex_unlock(&tb->lock);
 
 out_free:
-	free_page((unsigned long)buf);
+	kfree(buf);
 	return ret ? ret : count;
 }
 
@@ -1624,7 +1624,7 @@ static ssize_t margining_eye_write(struct file *file,
 			ret = -EINVAL;
 	}
 
-	free_page((unsigned long)buf);
+	kfree(buf);
 	return ret ? ret : count;
 }
 
@@ -1934,7 +1934,7 @@ static ssize_t counters_write(struct file *file, const char __user *user_buf,
 out:
 	pm_runtime_mark_last_busy(&sw->dev);
 	pm_runtime_put_autosuspend(&sw->dev);
-	free_page((unsigned long)buf);
+	kfree(buf);
 
 	return ret < 0 ? ret : count;
 }
diff --git a/drivers/thunderbolt/dma_test.c b/drivers/thunderbolt/dma_test.c
--- a/drivers/thunderbolt/dma_test.c
+++ b/drivers/thunderbolt/dma_test.c
@@ -636,7 +636,7 @@ static void dma_test_debugfs_init(struct tb_service *svc)
 	debugfs_create_file("test", 0200, debugfs_dir, svc, &test_fops);
 }
 
-static int dma_test_probe(struct tb_service *svc, const struct tb_service_id *id)
+static int dma_test_probe(struct tb_service *svc)
 {
 	struct tb_xdomain *xd = tb_service_parent(svc);
 	struct dma_test *dt;
@@ -689,7 +689,7 @@ static const struct dev_pm_ops dma_test_pm_ops = {
 
 static const struct tb_service_id dma_test_ids[] = {
 	{ TB_SERVICE("dma_test", 1) },
-	{ },
+	{ }
 };
 MODULE_DEVICE_TABLE(tbsvc, dma_test_ids);
 
diff --git a/drivers/thunderbolt/domain.c b/drivers/thunderbolt/domain.c
--- a/drivers/thunderbolt/domain.c
+++ b/drivers/thunderbolt/domain.c
@@ -77,12 +77,10 @@ static int tb_service_probe(struct device *dev)
 {
 	struct tb_service *svc = tb_to_service(dev);
 	struct tb_service_driver *driver;
-	const struct tb_service_id *id;
 
 	driver = container_of(dev->driver, struct tb_service_driver, driver);
-	id = __tb_service_match(dev, &driver->driver);
 
-	return driver->probe(svc, id);
+	return driver->probe(svc);
 }
 
 static void tb_service_remove(struct device *dev)
@@ -790,6 +788,21 @@ int tb_domain_approve_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
 			transmit_ring, receive_path, receive_ring);
 }
 
+static void tb_domain_reset_interface(struct tb *tb)
+{
+	struct tb_nhi *nhi = tb->nhi;
+
+	if (!nhi->ops->reset_interface)
+		return;
+
+	guard(mutex)(&tb->lock);
+
+	/* The reset clears the ring state so stop the control channel */
+	tb_ctl_stop(tb->ctl);
+	nhi->ops->reset_interface(nhi);
+	tb_ctl_start(tb->ctl);
+}
+
 /**
  * tb_domain_disconnect_xdomain_paths() - Disable DMA paths for XDomain
  * @tb: Domain disabling the DMA paths
@@ -812,11 +825,20 @@ int tb_domain_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
 				       int transmit_path, int transmit_ring,
 				       int receive_path, int receive_ring)
 {
+	int ret;
+
 	if (!tb->cm_ops->disconnect_xdomain_paths)
 		return -ENOTSUPP;
 
-	return tb->cm_ops->disconnect_xdomain_paths(tb, xd, transmit_path,
+	ret = tb->cm_ops->disconnect_xdomain_paths(tb, xd, transmit_path,
 			transmit_ring, receive_path, receive_ring);
+	if (ret)
+		return ret;
+
+	if (tb->nhi->quirks & QUIRK_RESET_DMA_ON_TEARDOWN)
+		tb_domain_reset_interface(tb);
+
+	return 0;
 }
 
 static int disconnect_xdomain(struct device *dev, void *data)
diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c
--- a/drivers/thunderbolt/nhi.c
+++ b/drivers/thunderbolt/nhi.c
@@ -235,6 +235,12 @@ static void ring_write_descriptors(struct tb_ring *ring)
 {
 	struct ring_frame *frame, *n;
 	struct ring_desc *descriptor;
+	u32 flags;
+
+	flags = RING_DESC_POSTED;
+	if (!(ring->flags & RING_FLAG_NO_INTERRUPT))
+		flags |= RING_DESC_INTERRUPT;
+
 	list_for_each_entry_safe(frame, n, &ring->queue, list) {
 		if (ring_full(ring))
 			break;
@@ -242,7 +248,7 @@ static void ring_write_descriptors(struct tb_ring *ring)
 		descriptor = &ring->descriptors[ring->head];
 		descriptor->phys = frame->buffer_phy;
 		descriptor->time = 0;
-		descriptor->flags = RING_DESC_POSTED | RING_DESC_INTERRUPT;
+		descriptor->flags = flags;
 		if (ring->is_tx) {
 			descriptor->length = frame->size;
 			descriptor->eof = frame->eof;
@@ -339,8 +345,9 @@ EXPORT_SYMBOL_GPL(__tb_ring_enqueue);
  * @ring: Ring to poll
  *
  * This function can be called when @start_poll callback of the @ring
- * has been called. It will read one completed frame from the ring and
- * return it to the caller.
+ * has been called or the ring is created with %RING_FLAG_NO_INTERRUPT.
+ * It will read one completed frame from the ring and return it to the
+ * caller.
  *
  * Return: Pointer to &struct ring_frame, %NULL if there is no more
  * completed frames.
@@ -538,6 +545,12 @@ static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
 	dev_dbg(nhi->dev, "allocating %s ring %d of size %d\n",
 		transmit ? "TX" : "RX", hop, size);
 
+	if ((flags & RING_FLAG_NO_INTERRUPT) && start_poll) {
+		dev_WARN(nhi->dev,
+			 "start_poll() and NO_INTERRUPT cannot be used at the same time\n");
+		return NULL;
+	}
+
 	ring = kzalloc_obj(*ring);
 	if (!ring)
 		return NULL;
@@ -568,7 +581,7 @@ static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
 	if (!ring->descriptors)
 		goto err_free_ring;
 
-	if (nhi->ops->request_ring_irq) {
+	if (!(flags & RING_FLAG_NO_INTERRUPT) && nhi->ops->request_ring_irq) {
 		if (nhi->ops->request_ring_irq(ring, flags & RING_FLAG_NO_SUSPEND))
 			goto err_free_descs;
 	}
@@ -701,7 +714,8 @@ void tb_ring_start(struct tb_ring *ring)
 		ring_iowrite32options(ring, flags, 0);
 	}
 
-	ring_interrupt_active(ring, true);
+	if (!(ring->flags & RING_FLAG_NO_INTERRUPT))
+		ring_interrupt_active(ring, true);
 	ring->running = true;
 err:
 	spin_unlock(&ring->lock);
@@ -761,7 +775,8 @@ void tb_ring_stop(struct tb_ring *ring)
 			 RING_TYPE(ring), ring->hop);
 		goto err;
 	}
-	ring_interrupt_active(ring, false);
+	if (!(ring->flags & RING_FLAG_NO_INTERRUPT))
+		ring_interrupt_active(ring, false);
 
 	ring_iowrite32options(ring, 0, 0);
 	ring_iowrite64desc(ring, 0, 0);
@@ -1160,6 +1175,32 @@ static void nhi_reset(struct tb_nhi *nhi)
 	dev_warn(nhi->dev, "timeout resetting host router\n");
 }
 
+/**
+ * nhi_reset_interface() - Reset the host interface
+ * @nhi: Host interface to reset
+ *
+ * Brings the registers in the memory BAR back to their default state and
+ * clears the End-to-End Flow Control state. The caller is responsible for
+ * stopping the control channel over the reset because it clears the ring
+ * state as well.
+ */
+void nhi_reset_interface(struct tb_nhi *nhi)
+{
+	u32 val;
+
+	val = ioread32(nhi->iobase + REG_CAPS);
+	/* Only v1 host interfaces implement the reset */
+	if (FIELD_GET(REG_CAPS_VERSION_MASK, val) >= REG_CAPS_VERSION_2)
+		return;
+
+	dev_dbg(nhi->dev, "issuing host interface reset\n");
+
+	iowrite32(REG_HOST_INTERFACE_RESET_RST,
+		  nhi->iobase + REG_HOST_INTERFACE_RESET);
+	/* Wait for tHIReset (10 ms) to complete */
+	usleep_range(10000, 20000);
+}
+
 static struct tb *nhi_select_cm(struct tb_nhi *nhi)
 {
 	struct tb *tb;
@@ -1235,6 +1276,8 @@ int nhi_probe(struct tb_nhi *nhi)
 
 	dev_dbg(dev, "NHI initialized, starting thunderbolt\n");
 
+	nhi->host_reset = host_reset;
+
 	res = tb_domain_add(tb, host_reset);
 	if (res) {
 		/*
diff --git a/drivers/thunderbolt/nhi.h b/drivers/thunderbolt/nhi.h
--- a/drivers/thunderbolt/nhi.h
+++ b/drivers/thunderbolt/nhi.h
@@ -36,6 +36,8 @@ irqreturn_t nhi_msi(int irq, void *data);
 irqreturn_t ring_msix(int irq, void *data);
 int nhi_probe(struct tb_nhi *nhi);
 void nhi_shutdown(struct tb_nhi *nhi);
+void nhi_reset_interface(struct tb_nhi *nhi);
+
 extern const struct dev_pm_ops nhi_pm_ops;
 
 /**
@@ -52,6 +54,7 @@ extern const struct dev_pm_ops nhi_pm_ops;
  * @release_ring_irq: NHI specific interrupt release hook
  * @is_present: Whether the device is currently present on the parent bus
  * @init_interrupts: NHI specific interrupt initialization hook
+ * @reset_interface: Resets the host interface
  */
 struct tb_nhi_ops {
 	int (*init)(struct tb_nhi *nhi);
@@ -66,6 +69,7 @@ struct tb_nhi_ops {
 	void (*release_ring_irq)(struct tb_ring *ring);
 	bool (*is_present)(struct tb_nhi *nhi);
 	int (*init_interrupts)(struct tb_nhi *nhi);
+	void (*reset_interface)(struct tb_nhi *nhi);
 };
 
 /*
@@ -116,11 +120,24 @@ struct tb_nhi_ops {
 #define PCI_DEVICE_ID_INTEL_PTL_P_NHI0			0xe433
 #define PCI_DEVICE_ID_INTEL_PTL_P_NHI1			0xe434
 
+#define PCI_DEVICE_ID_AMD_1AH_M60H_NHI0			0x1120
+#define PCI_DEVICE_ID_AMD_1AH_M60H_NHI1			0x1121
+#define PCI_DEVICE_ID_AMD_1AH_M68H_NHI0			0x113b
+#define PCI_DEVICE_ID_AMD_1AH_M68H_NHI1			0x113c
+#define PCI_DEVICE_ID_AMD_1AH_M80H_NHI0			0x1155
+#define PCI_DEVICE_ID_AMD_1AH_M80H_NHI1			0x1158
+#define PCI_DEVICE_ID_AMD_1AH_M80H_NHI2			0x1159
+#define PCI_DEVICE_ID_AMD_1AH_M24H_NHI0			0x151c
+#define PCI_DEVICE_ID_AMD_1AH_M24H_NHI1			0x151d
+#define PCI_DEVICE_ID_AMD_1AH_M70H_NHI0			0x158d
+#define PCI_DEVICE_ID_AMD_1AH_M70H_NHI1			0x158e
+
 #define PCI_CLASS_SERIAL_USB_USB4			0x0c0340
 
 /* Host interface quirks */
-#define QUIRK_AUTO_CLEAR_INT	BIT(0)
-#define QUIRK_E2E		BIT(1)
+#define QUIRK_AUTO_CLEAR_INT				BIT(0)
+#define QUIRK_E2E					BIT(1)
+#define QUIRK_RESET_DMA_ON_TEARDOWN			BIT(2)
 
 /*
  * Minimal number of vectors when we use MSI-X. Two for control channel
diff --git a/drivers/thunderbolt/nhi_regs.h b/drivers/thunderbolt/nhi_regs.h
--- a/drivers/thunderbolt/nhi_regs.h
+++ b/drivers/thunderbolt/nhi_regs.h
@@ -115,6 +115,10 @@ struct ring_desc {
 #define REG_CAPS_VERSION_MASK		GENMASK(23, 16)
 #define REG_CAPS_VERSION_2		0x40
 
+/* Host Interface Reset - resets TX/RX rings and E2E flow control counters */
+#define REG_HOST_INTERFACE_RESET	0x39858
+#define REG_HOST_INTERFACE_RESET_RST	BIT(0)
+
 #define REG_DMA_MISC			0x39864
 #define REG_DMA_MISC_INT_AUTO_CLEAR     BIT(2)
 #define REG_DMA_MISC_DISABLE_AUTO_CLEAR	BIT(17)
diff --git a/drivers/thunderbolt/pci.c b/drivers/thunderbolt/pci.c
--- a/drivers/thunderbolt/pci.c
+++ b/drivers/thunderbolt/pci.c
@@ -62,6 +62,27 @@ static void nhi_pci_check_quirks(struct tb_nhi_pci *nhi_pci)
 			nhi->quirks |= QUIRK_E2E;
 			break;
 		}
+	} else if (pdev->vendor == PCI_VENDOR_ID_AMD) {
+		switch (pdev->device) {
+		case PCI_DEVICE_ID_AMD_1AH_M60H_NHI0:
+		case PCI_DEVICE_ID_AMD_1AH_M60H_NHI1:
+		case PCI_DEVICE_ID_AMD_1AH_M68H_NHI0:
+		case PCI_DEVICE_ID_AMD_1AH_M68H_NHI1:
+		case PCI_DEVICE_ID_AMD_1AH_M80H_NHI0:
+		case PCI_DEVICE_ID_AMD_1AH_M80H_NHI1:
+		case PCI_DEVICE_ID_AMD_1AH_M80H_NHI2:
+		case PCI_DEVICE_ID_AMD_1AH_M24H_NHI0:
+		case PCI_DEVICE_ID_AMD_1AH_M24H_NHI1:
+		case PCI_DEVICE_ID_AMD_1AH_M70H_NHI0:
+		case PCI_DEVICE_ID_AMD_1AH_M70H_NHI1:
+			/*
+			 * These AMD hosts may hang the Tx ring when the
+			 * DMA paths are torn down so they need the host
+			 * interface reset after each teardown.
+			 */
+			nhi->quirks |= QUIRK_RESET_DMA_ON_TEARDOWN;
+			break;
+		}
 	}
 }
 
@@ -112,7 +133,6 @@ static int nhi_pci_init_msi(struct tb_nhi *nhi)
 {
 	struct tb_nhi_pci *nhi_pci = nhi_to_pci(nhi);
 	struct pci_dev *pdev = to_pci_dev(nhi->dev);
-	struct device *dev = &pdev->dev;
 	int res, irq, nvec;
 
 	ida_init(&nhi_pci->msix_ida);
@@ -139,7 +159,7 @@ static int nhi_pci_init_msi(struct tb_nhi *nhi)
 		res = devm_request_irq(&pdev->dev, irq, nhi_msi,
 				       IRQF_NO_SUSPEND, "thunderbolt", nhi);
 		if (res)
-			return dev_err_probe(dev, res, "request_irq failed, aborting\n");
+			return res;
 	}
 
 	return 0;
@@ -230,7 +250,7 @@ static void nhi_pci_ring_release_msix(struct tb_ring *ring)
 	ring->irq = 0;
 }
 
-static void nhi_pci_shutdown(struct tb_nhi *nhi)
+static void nhi_pci_release_irq(struct tb_nhi *nhi)
 {
 	struct tb_nhi_pci *nhi_pci = nhi_to_pci(nhi);
 	struct pci_dev *pdev = to_pci_dev(nhi->dev);
@@ -256,9 +276,10 @@ static const struct tb_nhi_ops pci_nhi_default_ops = {
 	.post_nvm_auth = nhi_pci_complete_dma_port,
 	.request_ring_irq = nhi_pci_ring_request_msix,
 	.release_ring_irq = nhi_pci_ring_release_msix,
-	.shutdown = nhi_pci_shutdown,
+	.shutdown = nhi_pci_release_irq,
 	.is_present = nhi_pci_is_present,
 	.init_interrupts = nhi_pci_init_msi,
+	.reset_interface = nhi_reset_interface,
 };
 
 /* Ice Lake specific NHI operations */
@@ -424,7 +445,7 @@ static int icl_nhi_resume(struct tb_nhi *nhi)
 
 static void icl_nhi_shutdown(struct tb_nhi *nhi)
 {
-	nhi_pci_shutdown(nhi);
+	nhi_pci_release_irq(nhi);
 
 	icl_nhi_force_power(nhi, false);
 }
@@ -442,6 +463,7 @@ static const struct tb_nhi_ops icl_nhi_ops = {
 	.release_ring_irq = nhi_pci_ring_release_msix,
 	.is_present = nhi_pci_is_present,
 	.init_interrupts = nhi_pci_init_msi,
+	.reset_interface = nhi_reset_interface,
 };
 
 static int nhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
@@ -479,11 +501,19 @@ static int nhi_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	return nhi_probe(&nhi_pci->nhi);
 }
 
-static void nhi_pci_remove(struct pci_dev *pdev)
+static void nhi_pci_do_remove(struct pci_dev *pdev, bool reset)
 {
 	struct tb *tb = pci_get_drvdata(pdev);
 	struct tb_nhi *nhi = tb->nhi;
 
+	/*
+	 * On system shutdown/reboot force a host router reset so the
+	 * connection manager asserts DPR on connected Thunderbolt 3 devices
+	 * before the router tree is removed (see tb_stop()).
+	 */
+	if (reset)
+		nhi->host_reset = true;
+
 	pm_runtime_get_sync(&pdev->dev);
 	pm_runtime_dont_use_autosuspend(&pdev->dev);
 	pm_runtime_forbid(&pdev->dev);
@@ -493,6 +523,16 @@ static void nhi_pci_remove(struct pci_dev *pdev)
 	nhi_shutdown(nhi);
 }
 
+static void nhi_pci_remove(struct pci_dev *pdev)
+{
+	nhi_pci_do_remove(pdev, false);
+}
+
+static void nhi_pci_shutdown(struct pci_dev *pdev)
+{
+	nhi_pci_do_remove(pdev, true);
+}
+
 static struct pci_device_id nhi_ids[] = {
 	/*
 	 * We have to specify class, the TB bridges use the same device and
@@ -593,7 +633,7 @@ static struct pci_driver nhi_driver = {
 	.id_table = nhi_ids,
 	.probe = nhi_pci_probe,
 	.remove = nhi_pci_remove,
-	.shutdown = nhi_pci_remove,
+	.shutdown = nhi_pci_shutdown,
 	.driver.pm = &nhi_pm_ops,
 };
 
diff --git a/drivers/thunderbolt/stream.c b/drivers/thunderbolt/stream.c
--- a/drivers/thunderbolt/stream.c
+++ b/drivers/thunderbolt/stream.c
@@ -9,10 +9,12 @@
 
 #define pr_fmt(fmt) "tbstream: " fmt
 
+#include <linux/delay.h>
 #include <linux/configfs.h>
 #include <linux/file.h>
 #include <linux/fs.h>
 #include <linux/idr.h>
+#include <linux/ktime.h>
 #include <linux/miscdevice.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
@@ -128,6 +130,7 @@ struct tbstream_ring {
  * @out_hopid: Out HopID
  * @ring_size: Size of the rings
  * @throttling: Interrupt throttling rate in ns
+ * @busy_poll: Instead of interrupts, busy poll the rings
  * @users: Number of times @cdev has been opened
  * @closed: CLOSE packet was received
  * @removed: Userspace removed the ConfigFS group underneath.
@@ -147,6 +150,7 @@ struct tbstream_dev {
 	int out_hopid;
 	unsigned int ring_size;
 	unsigned int throttling;
+	bool busy_poll;
 	int users;
 	bool closed;
 	bool removed;
@@ -536,10 +540,39 @@ tbstream_dev_send_data(struct tbstream_dev *sdev, struct iov_iter *from,
 	return tb_ring_tx(sdev->tx_ring.ring, &sf->frame);
 }
 
+static void
+tbstream_dev_poll_ring(struct tbstream_dev *sdev, struct tbstream_ring *ring)
+{
+	struct ring_frame *frame;
+
+	if (!sdev->busy_poll)
+		return;
+
+	while ((frame = tb_ring_poll(ring->ring)))
+		frame->callback(ring->ring, frame, false);
+}
+
 static int tbstream_dev_send_close(struct tbstream_dev *sdev)
 {
 	struct tbstream_frame *sf;
 
+	if (sdev->busy_poll) {
+		/*
+		 * When busy polling it's the write(2) path that
+		 * advances the completions so it is possible that the
+		 * ring is full at this point. Advance the ring here so
+		 * that there is room for the CLOSE packet to be sent.
+		 */
+		ktime_t timeout = ktime_add_ms(ktime_get(), 500);
+
+		do {
+			if (tbstream_ring_available(&sdev->tx_ring))
+				break;
+			tbstream_dev_poll_ring(sdev, &sdev->tx_ring);
+			fsleep(15);
+		} while (ktime_before(ktime_get(), timeout));
+	}
+
 	sf = tbstream_dev_alloc_tx(sdev, TBSTREAM_CLOSE, NULL, SZ_256);
 	if (IS_ERR(sf))
 		return PTR_ERR(sf);
@@ -549,12 +582,15 @@ static int tbstream_dev_send_close(struct tbstream_dev *sdev)
 static int tbstream_dev_start(struct tbstream_dev *sdev)
 {
 	struct tb_xdomain *xd = tbstream_dev_xdomain(sdev);
+	unsigned int flags = RING_FLAG_FRAME | RING_FLAG_E2E;
 	u16 sof_mask, eof_mask;
 	struct tb_ring *ring;
 	int ret, e2e_tx_hop;
 
-	ring = tb_ring_alloc_tx(xd->tb->nhi, -1, sdev->ring_size,
-				RING_FLAG_FRAME | RING_FLAG_E2E);
+	if (sdev->busy_poll)
+		flags |= RING_FLAG_NO_INTERRUPT;
+
+	ring = tb_ring_alloc_tx(xd->tb->nhi, -1, sdev->ring_size, flags);
 	if (!ring)
 		return -ENOMEM;
 	sdev->tx_ring.ring = ring;
@@ -567,9 +603,8 @@ static int tbstream_dev_start(struct tbstream_dev *sdev)
 	sof_mask = BIT(TBSTREAM_FRAME_START);
 	eof_mask = BIT(TBSTREAM_DATA) | BIT(TBSTREAM_CLOSE);
 
-	ring = tb_ring_alloc_rx(xd->tb->nhi, -1, sdev->ring_size,
-				RING_FLAG_FRAME | RING_FLAG_E2E, e2e_tx_hop,
-				sof_mask, eof_mask, NULL, NULL);
+	ring = tb_ring_alloc_rx(xd->tb->nhi, -1, sdev->ring_size, flags,
+				e2e_tx_hop, sof_mask, eof_mask, NULL, NULL);
 	if (!ring) {
 		ret = -ENOMEM;
 		goto err_free_tx_buffers;
@@ -607,15 +642,43 @@ static int tbstream_dev_start(struct tbstream_dev *sdev)
 	return ret;
 }
 
+static bool tbstream_dev_tx_drained(const struct tbstream_dev *sdev)
+{
+	const struct tbstream_ring *ring = &sdev->tx_ring;
+
+	/*
+	 * Everything is completed when number of free TX slots is back
+	 * to the maximum.
+	 */
+	return ring->prod - ring->cons == tb_ring_size(ring->ring) - 1;
+}
+
 static void tbstream_dev_stop(struct tbstream_dev *sdev)
 {
 	struct tb_xdomain *xd;
 
-	/* Wait for the ring to complete any outstanding frames */
-	tb_ring_flush(sdev->tx_ring.ring, 500);
-	tb_ring_stop(sdev->tx_ring.ring);
-	tb_ring_flush(sdev->rx_ring.ring, 500);
-	tb_ring_stop(sdev->rx_ring.ring);
+	if (sdev->busy_poll) {
+		/*
+		 * When busy polling we must advance the ring ourselves
+		 * to push all outstanding frames on the wire.
+		 */
+		ktime_t timeout = ktime_add_ms(ktime_get(), 500);
+
+		do {
+			if (tbstream_dev_tx_drained(sdev))
+				break;
+			tbstream_dev_poll_ring(sdev, &sdev->tx_ring);
+			fsleep(15);
+		} while (ktime_before(ktime_get(), timeout));
+
+		tb_ring_stop(sdev->tx_ring.ring);
+		tb_ring_stop(sdev->rx_ring.ring);
+	} else {
+		tb_ring_flush(sdev->tx_ring.ring, 500);
+		tb_ring_stop(sdev->tx_ring.ring);
+		tb_ring_flush(sdev->rx_ring.ring, 500);
+		tb_ring_stop(sdev->rx_ring.ring);
+	}
 
 	xd = tbstream_dev_xdomain(sdev);
 	if (xd) {
@@ -633,10 +696,24 @@ static void tbstream_dev_stop(struct tbstream_dev *sdev)
 	sdev->tx_ring.ring = NULL;
 }
 
+/* Use only with read_iter/write_iter() to handle nowait */
+static int tbstream_dev_lock(struct tbstream_dev *sdev, bool nowait)
+{
+	if (nowait) {
+		if (!mutex_trylock(&sdev->lock))
+			return -EAGAIN;
+	} else {
+		if (mutex_lock_interruptible(&sdev->lock))
+			return -ERESTARTSYS;
+	}
+	return 0;
+}
+
 static ssize_t
 tbstream_dev_fops_read_iter(struct kiocb *kiocb, struct iov_iter *to)
 {
 	struct file *file = kiocb->ki_filp;
+	bool nowait = file->f_flags & O_NONBLOCK || kiocb->ki_flags & IOCB_NOWAIT;
 	struct tbstream_dev *sdev = to_tbstream_dev(file->private_data);
 	size_t nbytes;
 	int ret;
@@ -645,31 +722,50 @@ tbstream_dev_fops_read_iter(struct kiocb *kiocb, struct iov_iter *to)
 	if (ret)
 		return ret;
 
-	if (mutex_lock_interruptible(&sdev->lock))
-		return -ERESTARTSYS;
+	ret = tbstream_dev_lock(sdev, nowait);
+	if (ret)
+		return ret;
 
-	while (!tbstream_ring_available(&sdev->rx_ring)) {
-		mutex_unlock(&sdev->lock);
-
-		if (file->f_flags & O_NONBLOCK)
-			return -EAGAIN;
-		ret = wait_event_interruptible(sdev->wait,
-				tbstream_ring_available(&sdev->rx_ring) ||
-				tbstream_dev_valid(sdev) != 0 ||
-				tbstream_dev_closed(sdev) ||
-				tbstream_dev_removed(sdev));
-		if (ret)
-			return ret;
+	for (;;) {
+		/* When busy polling, advance any completions manually */
+		tbstream_dev_poll_ring(sdev, &sdev->rx_ring);
 
 		ret = tbstream_dev_valid(sdev);
+		if (ret) {
+			mutex_unlock(&sdev->lock);
+			return ret;
+		}
+
+		if (tbstream_dev_closed(sdev) || tbstream_dev_removed(sdev)) {
+			mutex_unlock(&sdev->lock);
+			return 0;
+		}
+
+		if (tbstream_ring_available(&sdev->rx_ring))
+			break;
+
+		mutex_unlock(&sdev->lock);
+
+		if (nowait)
+			return -EAGAIN;
+
+		if (sdev->busy_poll) {
+			if (signal_pending(current))
+				return -ERESTARTSYS;
+			cond_resched();
+		} else {
+			ret = wait_event_interruptible(sdev->wait,
+					tbstream_ring_available(&sdev->rx_ring) ||
+					tbstream_dev_valid(sdev) != 0 ||
+					tbstream_dev_closed(sdev) ||
+					tbstream_dev_removed(sdev));
+			if (ret)
+				return ret;
+		}
+
+		ret = tbstream_dev_lock(sdev, nowait);
 		if (ret)
 			return ret;
-
-		if (tbstream_dev_closed(sdev) || tbstream_dev_removed(sdev))
-			return 0;
-
-		if (mutex_lock_interruptible(&sdev->lock))
-			return -ERESTARTSYS;
 	}
 
 	nbytes = 0;
@@ -729,6 +825,7 @@ static ssize_t
 tbstream_dev_fops_write_iter(struct kiocb *kiocb, struct iov_iter *from)
 {
 	struct file *file = kiocb->ki_filp;
+	bool nowait = file->f_flags & O_NONBLOCK || kiocb->ki_flags & IOCB_NOWAIT;
 	struct tbstream_dev *sdev = to_tbstream_dev(file->private_data);
 	size_t nbytes;
 	int ret;
@@ -737,31 +834,49 @@ tbstream_dev_fops_write_iter(struct kiocb *kiocb, struct iov_iter *from)
 	if (ret)
 		return ret;
 
-	if (mutex_lock_interruptible(&sdev->lock))
-		return -ERESTARTSYS;
+	ret = tbstream_dev_lock(sdev, nowait);
+	if (ret)
+		return ret;
 
-	while (!tbstream_ring_available(&sdev->tx_ring)) {
-		mutex_unlock(&sdev->lock);
-
-		if (file->f_flags & O_NONBLOCK)
-			return -EAGAIN;
-		ret = wait_event_interruptible(sdev->wait,
-				tbstream_ring_available(&sdev->tx_ring) ||
-				tbstream_dev_valid(sdev) != 0 ||
-				tbstream_dev_closed(sdev) ||
-				tbstream_dev_removed(sdev));
-		if (ret)
-			return ret;
+	for (;;) {
+		tbstream_dev_poll_ring(sdev, &sdev->tx_ring);
 
 		ret = tbstream_dev_valid(sdev);
+		if (ret) {
+			mutex_unlock(&sdev->lock);
+			return ret;
+		}
+
+		if (tbstream_dev_closed(sdev) || tbstream_dev_removed(sdev)) {
+			mutex_unlock(&sdev->lock);
+			return -ENXIO;
+		}
+
+		if (tbstream_ring_available(&sdev->tx_ring))
+			break;
+
+		mutex_unlock(&sdev->lock);
+
+		if (nowait)
+			return -EAGAIN;
+
+		if (sdev->busy_poll) {
+			if (signal_pending(current))
+				return -ERESTARTSYS;
+			cond_resched();
+		} else {
+			ret = wait_event_interruptible(sdev->wait,
+					tbstream_ring_available(&sdev->tx_ring) ||
+					tbstream_dev_valid(sdev) != 0 ||
+					tbstream_dev_closed(sdev) ||
+					tbstream_dev_removed(sdev));
+			if (ret)
+				return ret;
+		}
+
+		ret = tbstream_dev_lock(sdev, nowait);
 		if (ret)
 			return ret;
-
-		if (tbstream_dev_closed(sdev) || tbstream_dev_removed(sdev))
-			return -ENXIO;
-
-		if (mutex_lock_interruptible(&sdev->lock))
-			return -ERESTARTSYS;
 	}
 
 	nbytes = 0;
@@ -795,6 +910,13 @@ tbstream_dev_fops_poll(struct file *file, struct poll_table_struct *wait)
 	struct tbstream_dev *sdev = to_tbstream_dev(file->private_data);
 	__poll_t mask = 0;
 
+	/*
+	 * Without interrupts there is nothing that can wake us up so
+	 * return failure instead.
+	 */
+	if (sdev->busy_poll)
+		return EPOLLERR;
+
 	poll_wait(file, &sdev->wait, wait);
 	guard(mutex)(&sdev->lock);
 	if (tbstream_dev_valid(sdev) != 0) {
@@ -904,6 +1026,35 @@ tbstream_dev_from_group(struct config_group *group)
 	return container_of(group, struct tbstream_dev, group);
 }
 
+static ssize_t tbstream_dev_busy_poll_show(struct config_item *item, char *buf)
+{
+	struct config_group *group = to_config_group(item);
+	struct tbstream_dev *sdev = tbstream_dev_from_group(group);
+
+	return sysfs_emit(buf, "%u\n", sdev->busy_poll);
+}
+
+static ssize_t
+tbstream_dev_busy_poll_store(struct config_item *item, const char *buf,
+			     size_t count)
+{
+	struct config_group *group = to_config_group(item);
+	struct tbstream_dev *sdev = tbstream_dev_from_group(group);
+	bool busy_poll;
+	int ret;
+
+	ret = kstrtobool(buf, &busy_poll);
+	if (ret)
+		return ret;
+
+	guard(mutex)(&sdev->lock);
+	if (sdev->users)
+		return -EBUSY;
+	sdev->busy_poll = busy_poll;
+	return count;
+}
+CONFIGFS_ATTR(tbstream_dev_, busy_poll);
+
 static ssize_t tbstream_dev_index_show(struct config_item *item, char *buf)
 {
 	struct config_group *group = to_config_group(item);
@@ -1210,6 +1361,7 @@ tbstream_dev_throttling_store(struct config_item *item, const char *buf,
 CONFIGFS_ATTR(tbstream_dev_, throttling);
 
 static struct configfs_attribute *tbstream_dev_attrs[] = {
+	&tbstream_dev_attr_busy_poll,
 	&tbstream_dev_attr_index,
 	&tbstream_dev_attr_in_hopid,
 	&tbstream_dev_attr_out_hopid,
@@ -1542,7 +1694,7 @@ static void tbstream_group_detach_stream(struct tbstream *stream)
 	config_group_put(&sg->group);
 }
 
-static int tbstream_probe(struct tb_service *svc, const struct tb_service_id *id)
+static int tbstream_probe(struct tb_service *svc)
 {
 	struct tbstream *stream;
 
@@ -1632,7 +1784,7 @@ static const struct dev_pm_ops tbstream_pm_ops = {
 
 static const struct tb_service_id tbstream_ids[] = {
 	{ TB_SERVICE("stream", 1) },
-	{ },
+	{ }
 };
 MODULE_DEVICE_TABLE(tbsvc, tbstream_ids);
 
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -682,7 +682,16 @@ int tb_port_disable(struct tb_port *port)
 	return __tb_port_enable(port, false);
 }
 
-static int tb_port_reset(struct tb_port *port)
+/**
+ * tb_port_reset() - Reset the port
+ * @port: Port to reset
+ *
+ * Resets @port. For USB4 ports this issues a USB4 port reset and for
+ * legacy ports the link controller port is reset.
+ *
+ * Return: %0 on success, negative errno otherwise.
+ */
+int tb_port_reset(struct tb_port *port)
 {
 	if (tb_switch_is_usb4(port->sw))
 		return port->cap_usb4 ? usb4_port_reset(port) : 0;
diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
--- a/drivers/thunderbolt/tb.c
+++ b/drivers/thunderbolt/tb.c
@@ -2941,7 +2941,9 @@ static void tb_handle_event(struct tb *tb, enum tb_cfg_pkg_type type,
 static void tb_stop(struct tb *tb)
 {
 	struct tb_cm *tcm = tb_priv(tb);
+	struct tb_nhi *nhi = tb->nhi;
 	struct tb_tunnel *tunnel;
+	struct tb_port *port;
 	struct tb_tunnel *n;
 
 	cancel_delayed_work(&tcm->remove_work);
@@ -2956,6 +2958,25 @@ static void tb_stop(struct tb *tb)
 			tb_tunnel_deactivate(tunnel);
 		tb_tunnel_put(tunnel);
 	}
+	/*
+	 * Signal disconnect to connected devices before the router tree is
+	 * removed below. A Thunderbolt 3 device directly connected to a USB4
+	 * host otherwise never receives a disconnect indication, leaving
+	 * firmware to poll the dead link for up to ~60 s which on some
+	 * platforms turns the shutdown into a warm reset. Asserting
+	 * PORT_CS_19.DPR drives SBTX low (USB4 spec section 6.9) so the device
+	 * detects SBRX low and goes to Uninitialized Unplugged immediately.
+	 */
+	if (nhi->host_reset) {
+		tb_switch_for_each_port(tb->root_switch, port) {
+			if (!tb_port_is_null(port) || !tb_port_has_remote(port))
+				continue;
+			if (tb_switch_is_usb4(port->remote->sw))
+				continue;
+			if (tb_port_reset(port))
+				tb_port_dbg(port, "downstream port reset failed, continuing\n");
+		}
+	}
 	tb_switch_remove(tb->root_switch);
 	tb->root_switch = NULL;
 	tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -1103,6 +1103,7 @@ int tb_port_clear_counter(struct tb_port *port, int counter);
 int tb_port_unlock(struct tb_port *port);
 int tb_port_enable(struct tb_port *port);
 int tb_port_disable(struct tb_port *port);
+int tb_port_reset(struct tb_port *port);
 int tb_port_alloc_in_hopid(struct tb_port *port, int hopid, int max_hopid);
 void tb_port_release_in_hopid(struct tb_port *port, int hopid);
 int tb_port_alloc_out_hopid(struct tb_port *port, int hopid, int max_hopid);
diff --git a/drivers/thunderbolt/tunnel.c b/drivers/thunderbolt/tunnel.c
--- a/drivers/thunderbolt/tunnel.c
+++ b/drivers/thunderbolt/tunnel.c
@@ -48,6 +48,9 @@
 #define TB_DP_AUX_PRIORITY		2
 #define TB_DP_AUX_WEIGHT		1
 
+/* struct tb_regs_hop::initial_credits is 7 bits wide */
+#define TB_MAX_CREDITS			127
+
 /* Minimum number of credits needed for PCIe path */
 #define TB_MIN_PCIE_CREDITS		6U
 /*
@@ -1778,8 +1781,7 @@ static int tb_dma_reserve_credits(struct tb_path_hop *hop, unsigned int credits)
 		if (available < TB_MIN_DMA_CREDITS)
 			return -ENOSPC;
 
-		while (credits > available)
-			credits--;
+		credits = min(credits, available);
 
 		tb_port_dbg(port, "reserving %u credits for DMA path\n",
 			    credits);
@@ -1908,7 +1910,7 @@ struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi,
 	struct tb_tunnel *tunnel;
 	size_t npaths = 0, i = 0;
 	struct tb_path *path;
-	int credits;
+	unsigned int credits;
 
 	/* Ring 0 is reserved for control channel */
 	if (WARN_ON(!receive_ring || !transmit_ring))
@@ -1931,6 +1933,11 @@ struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi,
 	tunnel->destroy = tb_dma_destroy;
 
 	credits = min_not_zero(dma_credits, nhi->sw->max_dma_credits);
+	if (credits > TB_MAX_CREDITS) {
+		tb_tunnel_dbg(tunnel, "%u credits do not fit a hop, using %u\n",
+			      credits, TB_MAX_CREDITS);
+		credits = TB_MAX_CREDITS;
+	}
 
 	if (receive_ring > 0) {
 		path = tb_path_alloc(tb, dst, receive_path, nhi, receive_ring, 0,
diff --git a/drivers/thunderbolt/xdomain.c b/drivers/thunderbolt/xdomain.c
--- a/drivers/thunderbolt/xdomain.c
+++ b/drivers/thunderbolt/xdomain.c
@@ -968,6 +968,9 @@ tb_xdp_schedule_request(struct tb *tb, const struct tb_xdp_header *hdr,
  */
 int tb_register_service_driver(struct tb_service_driver *drv)
 {
+	if (!drv->probe)
+		return -EINVAL;
+
 	drv->driver.bus = &tb_bus_type;
 	return driver_register(&drv->driver);
 }
@@ -1811,6 +1814,7 @@ static void tb_xdomain_state_work(struct work_struct *work)
 			tb_xdomain_failed(xd);
 		} else {
 			xd->state = XDOMAIN_STATE_ENUMERATED;
+			tb_xdomain_queue_properties_changed(xd);
 		}
 		break;
 
diff --git a/include/linux/thunderbolt.h b/include/linux/thunderbolt.h
--- a/include/linux/thunderbolt.h
+++ b/include/linux/thunderbolt.h
@@ -465,7 +465,7 @@ static inline struct tb_service *tb_to_service(struct device *dev)
  */
 struct tb_service_driver {
 	struct device_driver driver;
-	int (*probe)(struct tb_service *svc, const struct tb_service_id *id);
+	int (*probe)(struct tb_service *svc);
 	void (*remove)(struct tb_service *svc);
 	void (*shutdown)(struct tb_service *svc);
 	const struct tb_service_id *id_table;
@@ -514,6 +514,11 @@ void tb_service_properties_changed(struct tb_service *svc);
  * @hop_count: Number of rings (end point hops) supported by NHI.
  * @quirks: NHI specific quirks if any
  * @domain_released: Completed when domain has been fully released
+ * @host_reset: Host router was reset on driver load, or forced on system
+ *		shutdown/reboot. When set, tb_stop() asserts DPR on connected
+ *		downstream ports to signal disconnect before tearing down the
+ *		router tree. Only Thunderbolt 3 devices are reset; USB4
+ *		routers are skipped.
  */
 struct tb_nhi {
 	spinlock_t lock;
@@ -528,6 +533,7 @@ struct tb_nhi {
 	u32 hop_count;
 	unsigned long quirks;
 	struct completion domain_released;
+	bool host_reset;
 };
 
 /**
@@ -592,6 +598,8 @@ struct tb_ring {
 #define RING_FLAG_FRAME		BIT(1)
 /* Enable end-to-end flow control */
 #define RING_FLAG_E2E		BIT(2)
+/* Do not enable interrupt for the ring */
+#define RING_FLAG_NO_INTERRUPT	BIT(3)
 
 struct ring_frame;
 typedef void (*ring_cb)(struct tb_ring *, struct ring_frame *, bool canceled);