From 90e91ccbdd0018481624d24a0e1b7528797ac2c7 Mon Sep 17 00:00:00 2001
From: Niklas Neronin <niklas.neronin@linux.intel.com>
Date: Wed, 6 Nov 2024 12:14:41 +0200
Subject: [PATCH 01/16] usb: xhci: rework xhci_link_segments()

Prepare for splitting ring segments allocation and initialization by
reworking the xhci_link_segments() function. Segment linking and ring type
checks are moved out of xhci_link_segments(), and the function is renamed
to "xhci_set_link_trb()".

The goal is to keep ring linking within xhci_alloc_segments_for_ring() and
move initialization into a separate function.

Additionally, reorder and simplify xhci_set_link_trb() for better
readability.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-16-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci-mem.c | 54 ++++++++++++++++++++-----------------
 1 file changed, 30 insertions(+), 24 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index feeaafc59a39..41a5e67e1c4f 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -86,33 +86,31 @@ static void xhci_ring_segments_free(struct xhci_hcd *xhci, struct xhci_ring *rin
 }
 
 /*
- * Make the prev segment point to the next segment.
+ * Only for transfer and command rings where driver is the producer, not for
+ * event rings.
  *
- * Change the last TRB in the prev segment to be a Link TRB which points to the
+ * Change the last TRB in the segment to be a Link TRB which points to the
  * DMA address of the next segment.  The caller needs to set any Link TRB
  * related flags, such as End TRB, Toggle Cycle, and no snoop.
  */
-static void xhci_link_segments(struct xhci_segment *prev,
-			       struct xhci_segment *next,
-			       enum xhci_ring_type type, bool chain_links)
+static void xhci_set_link_trb(struct xhci_segment *seg, bool chain_links)
 {
+	union xhci_trb *trb;
 	u32 val;
 
-	if (!prev || !next)
+	if (!seg || !seg->next)
 		return;
-	prev->next = next;
-	if (type != TYPE_EVENT) {
-		prev->trbs[TRBS_PER_SEGMENT-1].link.segment_ptr =
-			cpu_to_le64(next->dma);
 
-		/* Set the last TRB in the segment to have a TRB type ID of Link TRB */
-		val = le32_to_cpu(prev->trbs[TRBS_PER_SEGMENT-1].link.control);
-		val &= ~TRB_TYPE_BITMASK;
-		val |= TRB_TYPE(TRB_LINK);
-		if (chain_links)
-			val |= TRB_CHAIN;
-		prev->trbs[TRBS_PER_SEGMENT-1].link.control = cpu_to_le32(val);
-	}
+	trb = &seg->trbs[TRBS_PER_SEGMENT - 1];
+
+	/* Set the last TRB in the segment to have a TRB type ID of Link TRB */
+	val = le32_to_cpu(trb->link.control);
+	val &= ~TRB_TYPE_BITMASK;
+	val |= TRB_TYPE(TRB_LINK);
+	if (chain_links)
+		val |= TRB_CHAIN;
+	trb->link.control = cpu_to_le32(val);
+	trb->link.segment_ptr = cpu_to_le64(seg->next->dma);
 }
 
 /*
@@ -127,8 +125,6 @@ static void xhci_link_rings(struct xhci_hcd *xhci, struct xhci_ring *src, struct
 	if (!src || !dst)
 		return;
 
-	chain_links = xhci_link_chain_quirk(xhci, dst->type);
-
 	/* If the cycle state is 0, set the cycle bit to 1 for all the TRBs */
 	if (dst->cycle_state == 0) {
 		xhci_for_each_ring_seg(src->first_seg, seg) {
@@ -137,8 +133,13 @@ static void xhci_link_rings(struct xhci_hcd *xhci, struct xhci_ring *src, struct
 		}
 	}
 
-	xhci_link_segments(src->last_seg, dst->enq_seg->next, dst->type, chain_links);
-	xhci_link_segments(dst->enq_seg, src->first_seg, dst->type, chain_links);
+	src->last_seg->next = dst->enq_seg->next;
+	dst->enq_seg->next = src->first_seg;
+	if (dst->type != TYPE_EVENT) {
+		chain_links = xhci_link_chain_quirk(xhci, dst->type);
+		xhci_set_link_trb(dst->enq_seg, chain_links);
+		xhci_set_link_trb(src->last_seg, chain_links);
+	}
 	dst->num_segs += src->num_segs;
 
 	if (dst->enq_seg == dst->last_seg) {
@@ -331,13 +332,18 @@ static int xhci_alloc_segments_for_ring(struct xhci_hcd *xhci, struct xhci_ring
 		if (!next)
 			goto free_segments;
 
-		xhci_link_segments(prev, next, ring->type, chain_links);
+		prev->next = next;
+		if (ring->type != TYPE_EVENT)
+			xhci_set_link_trb(prev, chain_links);
 		prev = next;
 		num++;
 	}
-	xhci_link_segments(prev, ring->first_seg, ring->type, chain_links);
 	ring->last_seg = prev;
 
+	ring->last_seg->next = ring->first_seg;
+	if (ring->type != TYPE_EVENT)
+		xhci_set_link_trb(prev, chain_links);
+
 	return 0;
 
 free_segments:
-- 
2.51.0


From f53ce003ccd523e83eda15e724aa7a79ae64f09f Mon Sep 17 00:00:00 2001
From: Niklas Neronin <niklas.neronin@linux.intel.com>
Date: Wed, 6 Nov 2024 12:14:42 +0200
Subject: [PATCH 02/16] usb: xhci: add xhci_initialize_ring_segments()

A ring consists of a list of segments, each containing a specific number of
TRBs. The xhci driver allocates and initializes ring segments and TRBs in
the same functions. This combined allocation and initialization process
leads to an issue where, after hibernation (S4 state), the xhci driver
frees all its memory and re-creates the rings, segments, and TRBs from
scratch.

Move all default ring segment initialization into function
xhci_initialize_ring_segments(). This function can be called to
reinitialize a ring without freeing and reallocating it.

Since xhci_alloc_segments_for_ring() no longer initializes segment TRBs,
xhci_initialize_ring_segments() is added to xhci_ring_expansion(). This
results in the last segment of the source ring having the 'LINK_TOGGLE'
bit set. Therefore, if the last source ring segment is not the last in
the destination ring, the 'LINK_TOGGLE' bit must be cleared.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-17-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci-mem.c | 41 +++++++++++++++++++++----------------
 1 file changed, 23 insertions(+), 18 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 41a5e67e1c4f..4295e9a4de50 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -113,6 +113,22 @@ static void xhci_set_link_trb(struct xhci_segment *seg, bool chain_links)
 	trb->link.segment_ptr = cpu_to_le64(seg->next->dma);
 }
 
+static void xhci_initialize_ring_segments(struct xhci_hcd *xhci, struct xhci_ring *ring)
+{
+	struct xhci_segment *seg;
+	bool chain_links;
+
+	if (ring->type == TYPE_EVENT)
+		return;
+
+	chain_links = xhci_link_chain_quirk(xhci, ring->type);
+	xhci_for_each_ring_seg(ring->first_seg, seg)
+		xhci_set_link_trb(seg, chain_links);
+
+	/* See section 4.9.2.1 and 6.4.4.1 */
+	ring->last_seg->trbs[TRBS_PER_SEGMENT - 1].link.control |= cpu_to_le32(LINK_TOGGLE);
+}
+
 /*
  * Link the src ring segments to the dst ring.
  * Set Toggle Cycle for the new ring if needed.
@@ -143,13 +159,13 @@ static void xhci_link_rings(struct xhci_hcd *xhci, struct xhci_ring *src, struct
 	dst->num_segs += src->num_segs;
 
 	if (dst->enq_seg == dst->last_seg) {
-		if (dst->type != TYPE_EVENT) {
+		if (dst->type != TYPE_EVENT)
 			dst->last_seg->trbs[TRBS_PER_SEGMENT-1].link.control
 				&= ~cpu_to_le32(LINK_TOGGLE);
-			src->last_seg->trbs[TRBS_PER_SEGMENT-1].link.control
-				|= cpu_to_le32(LINK_TOGGLE);
-		}
+
 		dst->last_seg = src->last_seg;
+	} else if (dst->type != TYPE_EVENT) {
+		src->last_seg->trbs[TRBS_PER_SEGMENT-1].link.control &= ~cpu_to_le32(LINK_TOGGLE);
 	}
 
 	for (seg = dst->enq_seg; seg != dst->last_seg; seg = seg->next)
@@ -315,9 +331,6 @@ static int xhci_alloc_segments_for_ring(struct xhci_hcd *xhci, struct xhci_ring
 {
 	struct xhci_segment *prev;
 	unsigned int num = 0;
-	bool chain_links;
-
-	chain_links = xhci_link_chain_quirk(xhci, ring->type);
 
 	prev = xhci_segment_alloc(xhci, ring->bounce_buf_len, num, flags);
 	if (!prev)
@@ -333,17 +346,12 @@ static int xhci_alloc_segments_for_ring(struct xhci_hcd *xhci, struct xhci_ring
 			goto free_segments;
 
 		prev->next = next;
-		if (ring->type != TYPE_EVENT)
-			xhci_set_link_trb(prev, chain_links);
 		prev = next;
 		num++;
 	}
 	ring->last_seg = prev;
 
 	ring->last_seg->next = ring->first_seg;
-	if (ring->type != TYPE_EVENT)
-		xhci_set_link_trb(prev, chain_links);
-
 	return 0;
 
 free_segments:
@@ -381,12 +389,7 @@ struct xhci_ring *xhci_ring_alloc(struct xhci_hcd *xhci, unsigned int num_segs,
 	if (ret)
 		goto fail;
 
-	/* Only event ring does not use link TRB */
-	if (type != TYPE_EVENT) {
-		/* See section 4.9.2.1 and 6.4.4.1 */
-		ring->last_seg->trbs[TRBS_PER_SEGMENT - 1].link.control |=
-			cpu_to_le32(LINK_TOGGLE);
-	}
+	xhci_initialize_ring_segments(xhci, ring);
 	xhci_initialize_ring_info(ring);
 	trace_xhci_ring_alloc(ring);
 	return ring;
@@ -424,6 +427,8 @@ int xhci_ring_expansion(struct xhci_hcd *xhci, struct xhci_ring *ring,
 	if (ret)
 		return -ENOMEM;
 
+	xhci_initialize_ring_segments(xhci, &new_ring);
+
 	if (ring->type == TYPE_STREAM) {
 		ret = xhci_update_stream_segment_mapping(ring->trb_address_map, ring,
 							 new_ring.first_seg, flags);
-- 
2.51.0


From d7b11fe5790203fcc0db182249d7bfd945e44ccb Mon Sep 17 00:00:00 2001
From: Kuangyi Chiang <ki.chiang65@gmail.com>
Date: Wed, 6 Nov 2024 12:14:43 +0200
Subject: [PATCH 03/16] xhci: Combine two if statements for Etron xHCI host

Combine two if statements, because these hosts have the same
quirk flags applied.

[Mathias: has stable tag because other fixes in series depend on this]

Fixes: 91f7a1524a92 ("xhci: Apply broken streams quirk to Etron EJ188 xHCI host")
Cc: stable@vger.kernel.org
Signed-off-by: Kuangyi Chiang <ki.chiang65@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-18-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci-pci.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 7803ff1f1c9f..db3c7e738213 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -394,12 +394,8 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
 		xhci->quirks |= XHCI_DEFAULT_PM_RUNTIME_ALLOW;
 
 	if (pdev->vendor == PCI_VENDOR_ID_ETRON &&
-			pdev->device == PCI_DEVICE_ID_EJ168) {
-		xhci->quirks |= XHCI_RESET_ON_RESUME;
-		xhci->quirks |= XHCI_BROKEN_STREAMS;
-	}
-	if (pdev->vendor == PCI_VENDOR_ID_ETRON &&
-			pdev->device == PCI_DEVICE_ID_EJ188) {
+	    (pdev->device == PCI_DEVICE_ID_EJ168 ||
+	     pdev->device == PCI_DEVICE_ID_EJ188)) {
 		xhci->quirks |= XHCI_RESET_ON_RESUME;
 		xhci->quirks |= XHCI_BROKEN_STREAMS;
 	}
-- 
2.51.0


From 76d98856b1c6d06ce18f32c20527a4f9d283e660 Mon Sep 17 00:00:00 2001
From: Kuangyi Chiang <ki.chiang65@gmail.com>
Date: Wed, 6 Nov 2024 12:14:44 +0200
Subject: [PATCH 04/16] xhci: Don't issue Reset Device command to Etron xHCI
 host

Sometimes the hub driver does not recognize the USB device connected
to the external USB2.0 hub when the system resumes from S4.

After the SetPortFeature(PORT_RESET) request is completed, the hub
driver calls the HCD reset_device callback, which will issue a Reset
Device command and free all structures associated with endpoints
that were disabled.

This happens when the xHCI driver issue a Reset Device command to
inform the Etron xHCI host that the USB device associated with a
device slot has been reset. Seems that the Etron xHCI host can not
perform this command correctly, affecting the USB device.

To work around this, the xHCI driver should obtain a new device slot
with reference to commit 651aaf36a7d7 ("usb: xhci: Handle USB transaction
error on address command"), which is another way to inform the Etron
xHCI host that the USB device has been reset.

Add a new XHCI_ETRON_HOST quirk flag to invoke the workaround in
xhci_discover_or_reset_device().

Fixes: 2a8f82c4ceaf ("USB: xhci: Notify the xHC when a device is reset.")
Cc: stable@vger.kernel.org
Signed-off-by: Kuangyi Chiang <ki.chiang65@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-19-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci-pci.c |  1 +
 drivers/usb/host/xhci.c     | 19 +++++++++++++++++++
 drivers/usb/host/xhci.h     |  1 +
 3 files changed, 21 insertions(+)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index db3c7e738213..4b8c93e59d6d 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -396,6 +396,7 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
 	if (pdev->vendor == PCI_VENDOR_ID_ETRON &&
 	    (pdev->device == PCI_DEVICE_ID_EJ168 ||
 	     pdev->device == PCI_DEVICE_ID_EJ188)) {
+		xhci->quirks |= XHCI_ETRON_HOST;
 		xhci->quirks |= XHCI_RESET_ON_RESUME;
 		xhci->quirks |= XHCI_BROKEN_STREAMS;
 	}
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index aa8c877f47ac..ae16253b53fb 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -3733,6 +3733,8 @@ void xhci_free_device_endpoint_resources(struct xhci_hcd *xhci,
 				xhci->num_active_eps);
 }
 
+static void xhci_free_dev(struct usb_hcd *hcd, struct usb_device *udev);
+
 /*
  * This submits a Reset Device Command, which will set the device state to 0,
  * set the device address to 0, and disable all the endpoints except the default
@@ -3803,6 +3805,23 @@ static int xhci_discover_or_reset_device(struct usb_hcd *hcd,
 						SLOT_STATE_DISABLED)
 		return 0;
 
+	if (xhci->quirks & XHCI_ETRON_HOST) {
+		/*
+		 * Obtaining a new device slot to inform the xHCI host that
+		 * the USB device has been reset.
+		 */
+		ret = xhci_disable_slot(xhci, udev->slot_id);
+		xhci_free_virt_device(xhci, udev->slot_id);
+		if (!ret) {
+			ret = xhci_alloc_dev(hcd, udev);
+			if (ret == 1)
+				ret = 0;
+			else
+				ret = -EINVAL;
+		}
+		return ret;
+	}
+
 	trace_xhci_discover_or_reset_device(slot_ctx);
 
 	xhci_dbg(xhci, "Resetting device with slot ID %u\n", slot_id);
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index d3b250c736b8..a0204e10486d 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1631,6 +1631,7 @@ struct xhci_hcd {
 #define XHCI_ZHAOXIN_HOST	BIT_ULL(46)
 #define XHCI_WRITE_64_HI_LO	BIT_ULL(47)
 #define XHCI_CDNS_SCTX_QUIRK	BIT_ULL(48)
+#define XHCI_ETRON_HOST	BIT_ULL(49)
 
 	unsigned int		num_active_eps;
 	unsigned int		limit_active_eps;
-- 
2.51.0


From 5e1c67abc9301d05130b7e267c204e7005503b33 Mon Sep 17 00:00:00 2001
From: Kuangyi Chiang <ki.chiang65@gmail.com>
Date: Wed, 6 Nov 2024 12:14:45 +0200
Subject: [PATCH 05/16] xhci: Fix control transfer error on Etron xHCI host

Performing a stability stress test on a USB3.0 2.5G ethernet adapter
results in errors like this:

[   91.441469] r8152 2-3:1.0 eth3: get_registers -71
[   91.458659] r8152 2-3:1.0 eth3: get_registers -71
[   91.475911] r8152 2-3:1.0 eth3: get_registers -71
[   91.493203] r8152 2-3:1.0 eth3: get_registers -71
[   91.510421] r8152 2-3:1.0 eth3: get_registers -71

The r8152 driver will periodically issue lots of control-IN requests
to access the status of ethernet adapter hardware registers during
the test.

This happens when the xHCI driver enqueue a control TD (which cross
over the Link TRB between two ring segments, as shown) in the endpoint
zero's transfer ring. Seems the Etron xHCI host can not perform this
TD correctly, causing the USB transfer error occurred, maybe the upper
driver retry that control-IN request can solve problem, but not all
drivers do this.

|     |
-------
| TRB | Setup Stage
-------
| TRB | Link
-------
-------
| TRB | Data Stage
-------
| TRB | Status Stage
-------
|     |

To work around this, the xHCI driver should enqueue a No Op TRB if
next available TRB is the Link TRB in the ring segment, this can
prevent the Setup and Data Stage TRB to be breaked by the Link TRB.

Check if the XHCI_ETRON_HOST quirk flag is set before invoking the
workaround in xhci_queue_ctrl_tx().

Fixes: d0e96f5a71a0 ("USB: xhci: Control transfer support.")
Cc: stable@vger.kernel.org
Signed-off-by: Kuangyi Chiang <ki.chiang65@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-20-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci-ring.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index f62b243d0fc4..517df97ef496 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -3733,6 +3733,20 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
 	if (!urb->setup_packet)
 		return -EINVAL;
 
+	if ((xhci->quirks & XHCI_ETRON_HOST) &&
+	    urb->dev->speed >= USB_SPEED_SUPER) {
+		/*
+		 * If next available TRB is the Link TRB in the ring segment then
+		 * enqueue a No Op TRB, this can prevent the Setup and Data Stage
+		 * TRB to be breaked by the Link TRB.
+		 */
+		if (trb_is_link(ep_ring->enqueue + 1)) {
+			field = TRB_TYPE(TRB_TR_NOOP) | ep_ring->cycle_state;
+			queue_trb(xhci, ep_ring, false, 0, 0,
+					TRB_INTR_TARGET(0), field);
+		}
+	}
+
 	/* 1 TRB for setup, 1 for status */
 	num_trbs = 2;
 	/*
-- 
2.51.0


From e735e957f2b9cfe4be486e0304732ec36928591f Mon Sep 17 00:00:00 2001
From: Kuangyi Chiang <ki.chiang65@gmail.com>
Date: Wed, 6 Nov 2024 12:14:46 +0200
Subject: [PATCH 06/16] xhci: Don't perform Soft Retry for Etron xHCI host

Since commit f8f80be501aa ("xhci: Use soft retry to recover faster from
transaction errors"), unplugging USB device while enumeration results in
errors like this:

[ 364.855321] xhci_hcd 0000:0b:00.0: ERROR Transfer event for disabled endpoint slot 5 ep 2
[ 364.864622] xhci_hcd 0000:0b:00.0: @0000002167656d70 67f03000 00000021 0c000000 05038001
[ 374.934793] xhci_hcd 0000:0b:00.0: Abort failed to stop command ring: -110
[ 374.958793] xhci_hcd 0000:0b:00.0: xHCI host controller not responding, assume dead
[ 374.967590] xhci_hcd 0000:0b:00.0: HC died; cleaning up
[ 374.973984] xhci_hcd 0000:0b:00.0: Timeout while waiting for configure endpoint command

Seems that Etorn xHCI host can not perform Soft Retry correctly, apply
XHCI_NO_SOFT_RETRY quirk to disable Soft Retry and then issue is gone.

This patch depends on commit a4a251f8c235 ("usb: xhci: do not perform
Soft Retry for some xHCI hosts").

Fixes: f8f80be501aa ("xhci: Use soft retry to recover faster from transaction errors")
Cc: stable@vger.kernel.org
Signed-off-by: Kuangyi Chiang <ki.chiang65@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-21-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci-pci.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 4b8c93e59d6d..0d49d9c390c1 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -399,6 +399,7 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
 		xhci->quirks |= XHCI_ETRON_HOST;
 		xhci->quirks |= XHCI_RESET_ON_RESUME;
 		xhci->quirks |= XHCI_BROKEN_STREAMS;
+		xhci->quirks |= XHCI_NO_SOFT_RETRY;
 	}
 
 	if (pdev->vendor == PCI_VENDOR_ID_RENESAS &&
-- 
2.51.0


From 74496f22f77fa5823fe3b7f7a16b319dc1203cb1 Mon Sep 17 00:00:00 2001
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Date: Wed, 6 Nov 2024 12:14:47 +0200
Subject: [PATCH 07/16] xhci: pci: Use standard pattern for device IDs
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

The definitions of vendor IDs follow the pattern PCI_VENDOR_ID_#vendor,
while device IDs — PCI_DEVICE_ID_#vendor_#device.

Update the ETRON device IDs to follow the above mentioned pattern.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-22-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci-pci.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 0d49d9c390c1..77f9fe7a7dcd 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -34,9 +34,9 @@
 #define PCI_DEVICE_ID_FRESCO_LOGIC_FL1100	0x1100
 #define PCI_DEVICE_ID_FRESCO_LOGIC_FL1400	0x1400
 
-#define PCI_VENDOR_ID_ETRON		0x1b6f
-#define PCI_DEVICE_ID_EJ168		0x7023
-#define PCI_DEVICE_ID_EJ188		0x7052
+#define PCI_VENDOR_ID_ETRON			0x1b6f
+#define PCI_DEVICE_ID_ETRON_EJ168		0x7023
+#define PCI_DEVICE_ID_ETRON_EJ188		0x7052
 
 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_XHCI	0x8c31
 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_XHCI	0x9c31
@@ -394,8 +394,8 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
 		xhci->quirks |= XHCI_DEFAULT_PM_RUNTIME_ALLOW;
 
 	if (pdev->vendor == PCI_VENDOR_ID_ETRON &&
-	    (pdev->device == PCI_DEVICE_ID_EJ168 ||
-	     pdev->device == PCI_DEVICE_ID_EJ188)) {
+	    (pdev->device == PCI_DEVICE_ID_ETRON_EJ168 ||
+	     pdev->device == PCI_DEVICE_ID_ETRON_EJ188)) {
 		xhci->quirks |= XHCI_ETRON_HOST;
 		xhci->quirks |= XHCI_RESET_ON_RESUME;
 		xhci->quirks |= XHCI_BROKEN_STREAMS;
-- 
2.51.0


From 0309ed83791c079f239c13e0c605210425cd1a61 Mon Sep 17 00:00:00 2001
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Date: Wed, 6 Nov 2024 12:14:48 +0200
Subject: [PATCH 08/16] xhci: pci: Fix indentation in the PCI device ID
 definitions

Some of the definitions are missing the one TAB, add it to them.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-23-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci-pci.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 77f9fe7a7dcd..b1f4dd3f9eff 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -28,8 +28,8 @@
 #define SPARSE_CNTL_ENABLE	0xC12C
 
 /* Device for a quirk */
-#define PCI_VENDOR_ID_FRESCO_LOGIC	0x1b73
-#define PCI_DEVICE_ID_FRESCO_LOGIC_PDK	0x1000
+#define PCI_VENDOR_ID_FRESCO_LOGIC		0x1b73
+#define PCI_DEVICE_ID_FRESCO_LOGIC_PDK		0x1000
 #define PCI_DEVICE_ID_FRESCO_LOGIC_FL1009	0x1009
 #define PCI_DEVICE_ID_FRESCO_LOGIC_FL1100	0x1100
 #define PCI_DEVICE_ID_FRESCO_LOGIC_FL1400	0x1400
@@ -38,8 +38,8 @@
 #define PCI_DEVICE_ID_ETRON_EJ168		0x7023
 #define PCI_DEVICE_ID_ETRON_EJ188		0x7052
 
-#define PCI_DEVICE_ID_INTEL_LYNXPOINT_XHCI	0x8c31
-#define PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_XHCI	0x9c31
+#define PCI_DEVICE_ID_INTEL_LYNXPOINT_XHCI		0x8c31
+#define PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_XHCI		0x9c31
 #define PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_XHCI	0x9cb1
 #define PCI_DEVICE_ID_INTEL_CHERRYVIEW_XHCI		0x22b5
 #define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_XHCI		0xa12f
-- 
2.51.0


From 39b52aae23f54b6bc3649a50c27ca1058d2c2a86 Mon Sep 17 00:00:00 2001
From: Niklas Neronin <niklas.neronin@linux.intel.com>
Date: Wed, 6 Nov 2024 12:14:49 +0200
Subject: [PATCH 09/16] usb: xhci: simplify TDs start and end naming scheme in
 struct 'xhci_td'

Old names:
 * start_seg - last_trb_seg
 * first_trb - last_trb

New names:
 * start_seg - end_seg
 * start_trb - end_trb

A Transfer Descriptor (TD) in the xhci driver is a data structure that
represents a single transaction to be performed by the USB host controller.
This transaction is defined by TRBs from 'start_trb' in 'start_seg' to
'end_trb' in 'end_seg'.

The terms "start" and "end" were chosen  over "first" and "last" for ease
of searching within the codebase. The ring structure uses 'first_seg' and
'last_seg', while the TD structure uses 'start_seg' and 'end_seg'.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-24-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci-ring.c | 68 ++++++++++++++++++------------------
 drivers/usb/host/xhci.c      |  2 +-
 drivers/usb/host/xhci.h      |  6 ++--
 3 files changed, 38 insertions(+), 38 deletions(-)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 517df97ef496..1b4c785c8dad 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -660,8 +660,8 @@ static int xhci_move_dequeue_past_td(struct xhci_hcd *xhci,
 
 	/*
 	 * We want to find the pointer, segment and cycle state of the new trb
-	 * (the one after current TD's last_trb). We know the cycle state at
-	 * hw_dequeue, so walk the ring until both hw_dequeue and last_trb are
+	 * (the one after current TD's end_trb). We know the cycle state at
+	 * hw_dequeue, so walk the ring until both hw_dequeue and end_trb are
 	 * found.
 	 */
 	do {
@@ -671,7 +671,7 @@ static int xhci_move_dequeue_past_td(struct xhci_hcd *xhci,
 			if (td_last_trb_found)
 				break;
 		}
-		if (new_deq == td->last_trb)
+		if (new_deq == td->end_trb)
 			td_last_trb_found = true;
 
 		if (cycle_found && trb_is_link(new_deq) &&
@@ -744,16 +744,16 @@ static void td_to_noop(struct xhci_hcd *xhci, struct xhci_ring *ep_ring,
 		       struct xhci_td *td, bool flip_cycle)
 {
 	struct xhci_segment *seg	= td->start_seg;
-	union xhci_trb *trb		= td->first_trb;
+	union xhci_trb *trb		= td->start_trb;
 
 	while (1) {
 		trb_to_noop(trb, TRB_TR_NOOP);
 
 		/* flip cycle if asked to */
-		if (flip_cycle && trb != td->first_trb && trb != td->last_trb)
+		if (flip_cycle && trb != td->start_trb && trb != td->end_trb)
 			trb->generic.field[3] ^= cpu_to_le32(TRB_CYCLE);
 
-		if (trb == td->last_trb)
+		if (trb == td->end_trb)
 			break;
 
 		next_trb(&seg, &trb);
@@ -978,7 +978,7 @@ static int xhci_invalidate_cancelled_tds(struct xhci_virt_ep *ep)
 		xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
 			       "Removing canceled TD starting at 0x%llx (dma) in stream %u URB %p",
 			       (unsigned long long)xhci_trb_virt_to_dma(
-				       td->start_seg, td->first_trb),
+				       td->start_seg, td->start_trb),
 			       td->urb->stream_id, td->urb);
 		list_del_init(&td->td_list);
 		ring = xhci_urb_to_transfer_ring(xhci, td->urb);
@@ -2078,7 +2078,7 @@ struct xhci_segment *trb_in_td(struct xhci_hcd *xhci, struct xhci_td *td, dma_ad
 	dma_addr_t end_trb_dma;
 	struct xhci_segment *cur_seg;
 
-	start_dma = xhci_trb_virt_to_dma(td->start_seg, td->first_trb);
+	start_dma = xhci_trb_virt_to_dma(td->start_seg, td->start_trb);
 	cur_seg = td->start_seg;
 
 	do {
@@ -2088,7 +2088,7 @@ struct xhci_segment *trb_in_td(struct xhci_hcd *xhci, struct xhci_td *td, dma_ad
 		end_seg_dma = xhci_trb_virt_to_dma(cur_seg,
 				&cur_seg->trbs[TRBS_PER_SEGMENT - 1]);
 		/* If the end TRB isn't in this segment, this is set to 0 */
-		end_trb_dma = xhci_trb_virt_to_dma(cur_seg, td->last_trb);
+		end_trb_dma = xhci_trb_virt_to_dma(cur_seg, td->end_trb);
 
 		if (debug)
 			xhci_warn(xhci,
@@ -2230,7 +2230,7 @@ static int finish_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 			    !list_empty(&td->cancelled_td_list)) {
 				xhci_dbg(xhci, "Already resolving halted ep for 0x%llx\n",
 					 (unsigned long long)xhci_trb_virt_to_dma(
-						 td->start_seg, td->first_trb));
+						 td->start_seg, td->start_trb));
 				return 0;
 			}
 			/* endpoint not halted, don't reset it */
@@ -2262,8 +2262,8 @@ static int finish_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 	}
 
 	/* Update ring dequeue pointer */
-	ep_ring->dequeue = td->last_trb;
-	ep_ring->deq_seg = td->last_trb_seg;
+	ep_ring->dequeue = td->end_trb;
+	ep_ring->deq_seg = td->end_seg;
 	inc_deq(xhci, ep_ring);
 
 	return xhci_td_cleanup(xhci, td, ep_ring, td->status);
@@ -2273,7 +2273,7 @@ static int finish_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 static u32 sum_trb_lengths(struct xhci_td *td, union xhci_trb *stop_trb)
 {
 	u32 sum;
-	union xhci_trb *trb = td->first_trb;
+	union xhci_trb *trb = td->start_trb;
 	struct xhci_segment *seg = td->start_seg;
 
 	for (sum = 0; trb != stop_trb; next_trb(&seg, &trb)) {
@@ -2428,7 +2428,7 @@ static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 		fallthrough;
 	case COMP_ISOCH_BUFFER_OVERRUN:
 		frame->status = -EOVERFLOW;
-		if (ep_trb != td->last_trb)
+		if (ep_trb != td->end_trb)
 			td->error_mid_td = true;
 		break;
 	case COMP_INCOMPATIBLE_DEVICE_ERROR:
@@ -2438,7 +2438,7 @@ static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 	case COMP_USB_TRANSACTION_ERROR:
 		frame->status = -EPROTO;
 		sum_trbs_for_length = true;
-		if (ep_trb != td->last_trb)
+		if (ep_trb != td->end_trb)
 			td->error_mid_td = true;
 		break;
 	case COMP_STOPPED:
@@ -2474,7 +2474,7 @@ static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 
 finish_td:
 	/* Don't give back TD yet if we encountered an error mid TD */
-	if (td->error_mid_td && ep_trb != td->last_trb) {
+	if (td->error_mid_td && ep_trb != td->end_trb) {
 		xhci_dbg(xhci, "Error mid isoc TD, wait for final completion event\n");
 		td->urb_length_set = true;
 		return 0;
@@ -2501,8 +2501,8 @@ static int skip_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
 	frame->actual_length = 0;
 
 	/* Update ring dequeue pointer */
-	ep->ring->dequeue = td->last_trb;
-	ep->ring->deq_seg = td->last_trb_seg;
+	ep->ring->dequeue = td->end_trb;
+	ep->ring->deq_seg = td->end_seg;
 	inc_deq(xhci, ep->ring);
 
 	return xhci_td_cleanup(xhci, td, ep->ring, status);
@@ -2529,7 +2529,7 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 	case COMP_SUCCESS:
 		ep->err_count = 0;
 		/* handle success with untransferred data as short packet */
-		if (ep_trb != td->last_trb || remaining) {
+		if (ep_trb != td->end_trb || remaining) {
 			xhci_warn(xhci, "WARN Successful completion on short TX\n");
 			xhci_dbg(xhci, "ep %#x - asked for %d bytes, %d bytes untransferred\n",
 				 td->urb->ep->desc.bEndpointAddress,
@@ -2562,7 +2562,7 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 		break;
 	}
 
-	if (ep_trb == td->last_trb)
+	if (ep_trb == td->end_trb)
 		td->urb->actual_length = requested - remaining;
 	else
 		td->urb->actual_length =
@@ -2795,8 +2795,8 @@ static int handle_tx_event(struct xhci_hcd *xhci,
 
 	if (td && td->error_mid_td && !trb_in_td(xhci, td, ep_trb_dma, false)) {
 		xhci_dbg(xhci, "Missing TD completion event after mid TD error\n");
-		ep_ring->dequeue = td->last_trb;
-		ep_ring->deq_seg = td->last_trb_seg;
+		ep_ring->dequeue = td->end_trb;
+		ep_ring->deq_seg = td->end_seg;
 		inc_deq(xhci, ep_ring);
 		xhci_td_cleanup(xhci, td, ep_ring, td->status);
 	}
@@ -3308,7 +3308,7 @@ static int prepare_transfer(struct xhci_hcd *xhci,
 	/* Add this TD to the tail of the endpoint ring's TD list */
 	list_add_tail(&td->td_list, &ep_ring->td_list);
 	td->start_seg = ep_ring->enq_seg;
-	td->first_trb = ep_ring->enqueue;
+	td->start_trb = ep_ring->enqueue;
 
 	return 0;
 }
@@ -3647,8 +3647,8 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
 			field &= ~TRB_CHAIN;
 			field |= TRB_IOC;
 			more_trbs_coming = false;
-			td->last_trb = ring->enqueue;
-			td->last_trb_seg = ring->enq_seg;
+			td->end_trb = ring->enqueue;
+			td->end_seg = ring->enq_seg;
 			if (xhci_urb_suitable_for_idt(urb)) {
 				memcpy(&send_addr, urb->transfer_buffer,
 				       trb_buff_len);
@@ -3696,8 +3696,8 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
 		ret = prepare_transfer(xhci, xhci->devs[slot_id],
 				       ep_index, urb->stream_id,
 				       1, urb, 1, mem_flags);
-		urb_priv->td[1].last_trb = ring->enqueue;
-		urb_priv->td[1].last_trb_seg = ring->enq_seg;
+		urb_priv->td[1].end_trb = ring->enqueue;
+		urb_priv->td[1].end_seg = ring->enq_seg;
 		field = TRB_TYPE(TRB_NORMAL) | ring->cycle_state | TRB_IOC;
 		queue_trb(xhci, ring, 0, 0, 0, TRB_INTR_TARGET(0), field);
 	}
@@ -3835,8 +3835,8 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
 	}
 
 	/* Save the DMA address of the last TRB in the TD */
-	td->last_trb = ep_ring->enqueue;
-	td->last_trb_seg = ep_ring->enq_seg;
+	td->end_trb = ep_ring->enqueue;
+	td->end_seg = ep_ring->enq_seg;
 
 	/* Queue status TRB - see Table 7 and sections 4.11.2.2 and 6.4.1.2.3 */
 	/* If the device sent data, the status stage is an OUT transfer */
@@ -4121,8 +4121,8 @@ static int xhci_queue_isoc_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
 				field |= TRB_CHAIN;
 			} else {
 				more_trbs_coming = false;
-				td->last_trb = ep_ring->enqueue;
-				td->last_trb_seg = ep_ring->enq_seg;
+				td->end_trb = ep_ring->enqueue;
+				td->end_seg = ep_ring->enq_seg;
 				field |= TRB_IOC;
 				if (trb_block_event_intr(xhci, num_tds, i, ir))
 					field |= TRB_BEI;
@@ -4188,14 +4188,14 @@ cleanup:
 	/* Use the first TD as a temporary variable to turn the TDs we've queued
 	 * into No-ops with a software-owned cycle bit. That way the hardware
 	 * won't accidentally start executing bogus TDs when we partially
-	 * overwrite them.  td->first_trb and td->start_seg are already set.
+	 * overwrite them.  td->start_trb and td->start_seg are already set.
 	 */
-	urb_priv->td[0].last_trb = ep_ring->enqueue;
+	urb_priv->td[0].end_trb = ep_ring->enqueue;
 	/* Every TRB except the first & last will have its cycle bit flipped. */
 	td_to_noop(xhci, ep_ring, &urb_priv->td[0], true);
 
 	/* Reset the ring enqueue back to the first TRB and its cycle bit. */
-	ep_ring->enqueue = urb_priv->td[0].first_trb;
+	ep_ring->enqueue = urb_priv->td[0].start_trb;
 	ep_ring->enq_seg = urb_priv->td[0].start_seg;
 	ep_ring->cycle_state = start_cycle;
 	usb_hcd_unlink_urb_from_ep(bus_to_hcd(urb->dev->bus), urb);
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index ae16253b53fb..a5ac1e01f82d 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1752,7 +1752,7 @@ static int xhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 				urb->ep->desc.bEndpointAddress,
 				(unsigned long long) xhci_trb_virt_to_dma(
 					urb_priv->td[i].start_seg,
-					urb_priv->td[i].first_trb));
+					urb_priv->td[i].start_trb));
 
 	for (; i < urb_priv->num_tds; i++) {
 		td = &urb_priv->td[i];
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index a0204e10486d..a0e992c3db0d 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1294,9 +1294,9 @@ struct xhci_td {
 	enum xhci_cancelled_td_status	cancel_status;
 	struct urb		*urb;
 	struct xhci_segment	*start_seg;
-	union xhci_trb		*first_trb;
-	union xhci_trb		*last_trb;
-	struct xhci_segment	*last_trb_seg;
+	union xhci_trb		*start_trb;
+	struct xhci_segment	*end_seg;
+	union xhci_trb		*end_trb;
 	struct xhci_segment	*bounce_seg;
 	/* actual_length of the URB has already been set */
 	bool			urb_length_set;
-- 
2.51.0


From 083ba4c46a1cdb2d4a2dbb0db1623fd73152af34 Mon Sep 17 00:00:00 2001
From: Niklas Neronin <niklas.neronin@linux.intel.com>
Date: Wed, 6 Nov 2024 12:14:50 +0200
Subject: [PATCH 10/16] usb: xhci: move link TRB quirk to xhci_gen_setup()

This quirk is old and seldom seen, as a result the trace is changed
to debug message and only printed when the quirk is set.

Move it into xhci_gen_setup() where the majority of quirks are set.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-25-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index a5ac1e01f82d..e5719fd45a38 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -473,14 +473,7 @@ static int xhci_init(struct usb_hcd *hcd)
 
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init, "xhci_init");
 	spin_lock_init(&xhci->lock);
-	if (xhci->hci_version == 0x95 && link_quirk) {
-		xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
-				"QUIRK: Not clearing Link TRB chain bits.");
-		xhci->quirks |= XHCI_LINK_TRB_QUIRK;
-	} else {
-		xhci_dbg_trace(xhci, trace_xhci_dbg_init,
-				"xHCI doesn't need link TRB QUIRK");
-	}
+
 	retval = xhci_mem_init(xhci, GFP_KERNEL);
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init, "Finished xhci_init");
 
@@ -5311,6 +5304,11 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks)
 	if (xhci->hci_version > 0x96)
 		xhci->quirks |= XHCI_SPURIOUS_SUCCESS;
 
+	if (xhci->hci_version == 0x95 && link_quirk) {
+		xhci_dbg(xhci, "QUIRK: Not clearing Link TRB chain bits");
+		xhci->quirks |= XHCI_LINK_TRB_QUIRK;
+	}
+
 	/* Make sure the HC is halted. */
 	retval = xhci_halt(xhci);
 	if (retval)
-- 
2.51.0


From 34fee04e7bdc4eb28385de31918fd74e57bb5dd2 Mon Sep 17 00:00:00 2001
From: Niklas Neronin <niklas.neronin@linux.intel.com>
Date: Wed, 6 Nov 2024 12:14:51 +0200
Subject: [PATCH 11/16] usb: xhci: request MSI/-X according to requested amount

Variable 'max_interrupters' contains the maximum supported interrupters
or the maximum interrupters the user has requested. Thus, it should be
used instead of HCS_MAX_INTRS().

User set 'max_interrupters' value is validated in xhci_gen_setup(),
otherwise 'max_interrupters' value is 'HCS_MAX_INTRS(xhci->hcs_params1)'.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-26-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci-pci.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index b1f4dd3f9eff..47c4f70793e4 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -149,14 +149,11 @@ static int xhci_try_enable_msi(struct usb_hcd *hcd)
 	hcd->irq = 0;
 
 	/*
-	 * calculate number of MSI-X vectors supported.
-	 * - HCS_MAX_INTRS: the max number of interrupts the host can handle,
-	 *   with max number of interrupters based on the xhci HCSPARAMS1.
-	 * - num_online_cpus: maximum MSI-X vectors per CPUs core.
-	 *   Add additional 1 vector to ensure always available interrupt.
+	 * Calculate number of MSI/MSI-X vectors supported.
+	 * - max_interrupters: the max number of interrupts requested, capped to xhci HCSPARAMS1.
+	 * - num_online_cpus: one vector per CPUs core, with at least one overall.
 	 */
-	xhci->nvecs = min(num_online_cpus() + 1,
-			  HCS_MAX_INTRS(xhci->hcs_params1));
+	xhci->nvecs = min(num_online_cpus() + 1, xhci->max_interrupters);
 
 	/* TODO: Check with MSI Soc for sysdev */
 	xhci->nvecs = pci_alloc_irq_vectors(pdev, 1, xhci->nvecs,
-- 
2.51.0


From 36b972d4b7cef5d098de63fee8d00720c051f335 Mon Sep 17 00:00:00 2001
From: Niklas Neronin <niklas.neronin@linux.intel.com>
Date: Wed, 6 Nov 2024 12:14:52 +0200
Subject: [PATCH 12/16] usb: xhci: improve xhci_clear_command_ring()

Remove redundant TRB cycle reset, the TRB cycle is already set to zero by
the preceding memset(), making the explicit reset unnecessary.

Clarify ring loop start point. Change the loop start from the dequeue
segment to the start segment. Both approaches achieve the same result,
but starting from the start segment makes it clearer that the entire ring
is being zeroed out.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-27-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index e5719fd45a38..bc477cf99805 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -778,10 +778,8 @@ static void xhci_clear_command_ring(struct xhci_hcd *xhci)
 	struct xhci_segment *seg;
 
 	ring = xhci->cmd_ring;
-	xhci_for_each_ring_seg(ring->deq_seg, seg) {
+	xhci_for_each_ring_seg(ring->first_seg, seg)
 		memset(seg->trbs, 0, sizeof(union xhci_trb) * (TRBS_PER_SEGMENT - 1));
-		seg->trbs[TRBS_PER_SEGMENT - 1].link.control &= cpu_to_le32(~TRB_CYCLE);
-	}
 
 	xhci_initialize_ring_info(ring);
 	/*
-- 
2.51.0


From 37d39db6dcff7d852079e9f9a66f41e1bd5b0a45 Mon Sep 17 00:00:00 2001
From: Niklas Neronin <niklas.neronin@linux.intel.com>
Date: Wed, 6 Nov 2024 12:14:53 +0200
Subject: [PATCH 13/16] usb: xhci: remove unused arguments from td_to_noop()

Function td_to_noop() does not utilize arguments 'xhci' and 'ep_ring'.
These unused arguments are removed to clean up the code.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-28-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci-ring.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 1b4c785c8dad..5fb3d771c429 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -740,8 +740,7 @@ static int xhci_move_dequeue_past_td(struct xhci_hcd *xhci,
  * (The last TRB actually points to the ring enqueue pointer, which is not part
  * of this TD.)  This is used to remove partially enqueued isoc TDs from a ring.
  */
-static void td_to_noop(struct xhci_hcd *xhci, struct xhci_ring *ep_ring,
-		       struct xhci_td *td, bool flip_cycle)
+static void td_to_noop(struct xhci_td *td, bool flip_cycle)
 {
 	struct xhci_segment *seg	= td->start_seg;
 	union xhci_trb *trb		= td->start_trb;
@@ -1020,16 +1019,16 @@ static int xhci_invalidate_cancelled_tds(struct xhci_virt_ep *ep)
 						  "Found multiple active URBs %p and %p in stream %u?\n",
 						  td->urb, cached_td->urb,
 						  td->urb->stream_id);
-					td_to_noop(xhci, ring, cached_td, false);
+					td_to_noop(cached_td, false);
 					cached_td->cancel_status = TD_CLEARED;
 				}
-				td_to_noop(xhci, ring, td, false);
+				td_to_noop(td, false);
 				td->cancel_status = TD_CLEARING_CACHE;
 				cached_td = td;
 				break;
 			}
 		} else {
-			td_to_noop(xhci, ring, td, false);
+			td_to_noop(td, false);
 			td->cancel_status = TD_CLEARED;
 		}
 	}
@@ -1054,7 +1053,7 @@ static int xhci_invalidate_cancelled_tds(struct xhci_virt_ep *ep)
 				continue;
 			xhci_warn(xhci, "Failed to clear cancelled cached URB %p, mark clear anyway\n",
 				  td->urb);
-			td_to_noop(xhci, ring, td, false);
+			td_to_noop(td, false);
 			td->cancel_status = TD_CLEARED;
 		}
 	}
@@ -4192,7 +4191,7 @@ cleanup:
 	 */
 	urb_priv->td[0].end_trb = ep_ring->enqueue;
 	/* Every TRB except the first & last will have its cycle bit flipped. */
-	td_to_noop(xhci, ep_ring, &urb_priv->td[0], true);
+	td_to_noop(&urb_priv->td[0], true);
 
 	/* Reset the ring enqueue back to the first TRB and its cycle bit. */
 	ep_ring->enqueue = urb_priv->td[0].start_trb;
-- 
2.51.0


From 7acfea2866acc6c888f880e28a249bc5ce069ad0 Mon Sep 17 00:00:00 2001
From: Niklas Neronin <niklas.neronin@linux.intel.com>
Date: Wed, 6 Nov 2024 12:14:54 +0200
Subject: [PATCH 14/16] usb: xhci: refactor xhci_td_cleanup() to return void

The function is modified to return 'void' instead of an integer since it
invariably returns '0'. Additionally, multiple functions which only
return xhci_td_cleanup() are also refactored to return void.

This change eliminates the need for callers to handle a return value that
does not convey meaningful information and improve code readability, as it
becomes immediately clear that the function does not produce a significant
output.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-29-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci-ring.c | 59 +++++++++++++++++-------------------
 1 file changed, 28 insertions(+), 31 deletions(-)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 5fb3d771c429..e48ee58fdb46 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -813,8 +813,8 @@ static void xhci_unmap_td_bounce_buffer(struct xhci_hcd *xhci,
 	seg->bounce_offs = 0;
 }
 
-static int xhci_td_cleanup(struct xhci_hcd *xhci, struct xhci_td *td,
-			   struct xhci_ring *ep_ring, int status)
+static void xhci_td_cleanup(struct xhci_hcd *xhci, struct xhci_td *td,
+			    struct xhci_ring *ep_ring, int status)
 {
 	struct urb *urb = NULL;
 
@@ -857,8 +857,6 @@ static int xhci_td_cleanup(struct xhci_hcd *xhci, struct xhci_td *td,
 			status = 0;
 		xhci_giveback_urb_in_irq(xhci, td, status);
 	}
-
-	return 0;
 }
 
 
@@ -2187,9 +2185,9 @@ int xhci_is_vendor_info_code(struct xhci_hcd *xhci, unsigned int trb_comp_code)
 	return 0;
 }
 
-static int finish_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
-		     struct xhci_ring *ep_ring, struct xhci_td *td,
-		     u32 trb_comp_code)
+static void finish_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
+		      struct xhci_ring *ep_ring, struct xhci_td *td,
+		      u32 trb_comp_code)
 {
 	struct xhci_ep_ctx *ep_ctx;
 
@@ -2204,7 +2202,7 @@ static int finish_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 		 * stopped TDs. A stopped TD may be restarted, so don't update
 		 * the ring dequeue pointer or take this TD off any lists yet.
 		 */
-		return 0;
+		return;
 	case COMP_USB_TRANSACTION_ERROR:
 	case COMP_BABBLE_DETECTED_ERROR:
 	case COMP_SPLIT_TRANSACTION_ERROR:
@@ -2230,7 +2228,7 @@ static int finish_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 				xhci_dbg(xhci, "Already resolving halted ep for 0x%llx\n",
 					 (unsigned long long)xhci_trb_virt_to_dma(
 						 td->start_seg, td->start_trb));
-				return 0;
+				return;
 			}
 			/* endpoint not halted, don't reset it */
 			break;
@@ -2238,7 +2236,7 @@ static int finish_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 		/* Almost same procedure as for STALL_ERROR below */
 		xhci_clear_hub_tt_buffer(xhci, td, ep);
 		xhci_handle_halted_endpoint(xhci, ep, td, EP_HARD_RESET);
-		return 0;
+		return;
 	case COMP_STALL_ERROR:
 		/*
 		 * xhci internal endpoint state will go to a "halt" state for
@@ -2255,7 +2253,7 @@ static int finish_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 
 		xhci_handle_halted_endpoint(xhci, ep, td, EP_HARD_RESET);
 
-		return 0; /* xhci_handle_halted_endpoint marked td cancelled */
+		return; /* xhci_handle_halted_endpoint marked td cancelled */
 	default:
 		break;
 	}
@@ -2265,7 +2263,7 @@ static int finish_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 	ep_ring->deq_seg = td->end_seg;
 	inc_deq(xhci, ep_ring);
 
-	return xhci_td_cleanup(xhci, td, ep_ring, td->status);
+	xhci_td_cleanup(xhci, td, ep_ring, td->status);
 }
 
 /* sum trb lengths from the first trb up to stop_trb, _excluding_ stop_trb */
@@ -2285,9 +2283,9 @@ static u32 sum_trb_lengths(struct xhci_td *td, union xhci_trb *stop_trb)
 /*
  * Process control tds, update urb status and actual_length.
  */
-static int process_ctrl_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
-		struct xhci_ring *ep_ring,  struct xhci_td *td,
-			   union xhci_trb *ep_trb, struct xhci_transfer_event *event)
+static void process_ctrl_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
+			    struct xhci_ring *ep_ring,  struct xhci_td *td,
+			    union xhci_trb *ep_trb, struct xhci_transfer_event *event)
 {
 	struct xhci_ep_ctx *ep_ctx;
 	u32 trb_comp_code;
@@ -2366,7 +2364,7 @@ static int process_ctrl_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 		td->urb_length_set = true;
 		td->urb->actual_length = requested - remaining;
 		xhci_dbg(xhci, "Waiting for status stage event\n");
-		return 0;
+		return;
 	}
 
 	/* at status stage */
@@ -2374,15 +2372,15 @@ static int process_ctrl_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 		td->urb->actual_length = requested;
 
 finish_td:
-	return finish_td(xhci, ep, ep_ring, td, trb_comp_code);
+	finish_td(xhci, ep, ep_ring, td, trb_comp_code);
 }
 
 /*
  * Process isochronous tds, update urb packet status and actual_length.
  */
-static int process_isoc_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
-		struct xhci_ring *ep_ring, struct xhci_td *td,
-		union xhci_trb *ep_trb, struct xhci_transfer_event *event)
+static void process_isoc_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
+			    struct xhci_ring *ep_ring, struct xhci_td *td,
+			    union xhci_trb *ep_trb, struct xhci_transfer_event *event)
 {
 	struct urb_priv *urb_priv;
 	int idx;
@@ -2476,14 +2474,13 @@ finish_td:
 	if (td->error_mid_td && ep_trb != td->end_trb) {
 		xhci_dbg(xhci, "Error mid isoc TD, wait for final completion event\n");
 		td->urb_length_set = true;
-		return 0;
+		return;
 	}
-
-	return finish_td(xhci, ep, ep_ring, td, trb_comp_code);
+	finish_td(xhci, ep, ep_ring, td, trb_comp_code);
 }
 
-static int skip_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
-			struct xhci_virt_ep *ep, int status)
+static void skip_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
+			 struct xhci_virt_ep *ep, int status)
 {
 	struct urb_priv *urb_priv;
 	struct usb_iso_packet_descriptor *frame;
@@ -2504,15 +2501,15 @@ static int skip_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
 	ep->ring->deq_seg = td->end_seg;
 	inc_deq(xhci, ep->ring);
 
-	return xhci_td_cleanup(xhci, td, ep->ring, status);
+	xhci_td_cleanup(xhci, td, ep->ring, status);
 }
 
 /*
  * Process bulk and interrupt tds, update urb status and actual_length.
  */
-static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
-		struct xhci_ring *ep_ring, struct xhci_td *td,
-		union xhci_trb *ep_trb, struct xhci_transfer_event *event)
+static void process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
+				 struct xhci_ring *ep_ring, struct xhci_td *td,
+				 union xhci_trb *ep_trb, struct xhci_transfer_event *event)
 {
 	struct xhci_slot_ctx *slot_ctx;
 	u32 trb_comp_code;
@@ -2555,7 +2552,7 @@ static int process_bulk_intr_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 		td->status = 0;
 
 		xhci_handle_halted_endpoint(xhci, ep, td, EP_SOFT_RESET);
-		return 0;
+		return;
 	default:
 		/* do nothing */
 		break;
@@ -2574,7 +2571,7 @@ finish_td:
 		td->urb->actual_length = 0;
 	}
 
-	return finish_td(xhci, ep, ep_ring, td, trb_comp_code);
+	finish_td(xhci, ep, ep_ring, td, trb_comp_code);
 }
 
 /* Transfer events which don't point to a transfer TRB, see xhci 4.17.4 */
-- 
2.51.0


From ee8ebec3c8d3a98f5fc0c4ab7793f06ab86eb6df Mon Sep 17 00:00:00 2001
From: Niklas Neronin <niklas.neronin@linux.intel.com>
Date: Wed, 6 Nov 2024 12:14:55 +0200
Subject: [PATCH 15/16] usb: xhci: add help function xhci_dequeue_td()

Add xhci_dequeue_td() helper function to reduce code duplication.

Function xhci_dequeue_td() advances the dequeue pointer past the specified
Transfer Descriptor (TD) and releases the TD.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-30-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci-ring.c | 29 +++++++++++++----------------
 1 file changed, 13 insertions(+), 16 deletions(-)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index e48ee58fdb46..c9c0c4a7588a 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -859,6 +859,16 @@ static void xhci_td_cleanup(struct xhci_hcd *xhci, struct xhci_td *td,
 	}
 }
 
+/* Give back previous TD and move on to the next TD. */
+static void xhci_dequeue_td(struct xhci_hcd *xhci, struct xhci_td *td, struct xhci_ring *ring,
+			    u32 status)
+{
+	ring->dequeue = td->end_trb;
+	ring->deq_seg = td->end_seg;
+	inc_deq(xhci, ring);
+
+	xhci_td_cleanup(xhci, td, ring, status);
+}
 
 /* Complete the cancelled URBs we unlinked from td_list. */
 static void xhci_giveback_invalidated_tds(struct xhci_virt_ep *ep)
@@ -2258,12 +2268,7 @@ static void finish_td(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
 		break;
 	}
 
-	/* Update ring dequeue pointer */
-	ep_ring->dequeue = td->end_trb;
-	ep_ring->deq_seg = td->end_seg;
-	inc_deq(xhci, ep_ring);
-
-	xhci_td_cleanup(xhci, td, ep_ring, td->status);
+	xhci_dequeue_td(xhci, td, ep_ring, td->status);
 }
 
 /* sum trb lengths from the first trb up to stop_trb, _excluding_ stop_trb */
@@ -2496,12 +2501,7 @@ static void skip_isoc_td(struct xhci_hcd *xhci, struct xhci_td *td,
 	/* calc actual length */
 	frame->actual_length = 0;
 
-	/* Update ring dequeue pointer */
-	ep->ring->dequeue = td->end_trb;
-	ep->ring->deq_seg = td->end_seg;
-	inc_deq(xhci, ep->ring);
-
-	xhci_td_cleanup(xhci, td, ep->ring, status);
+	xhci_dequeue_td(xhci, td, ep->ring, status);
 }
 
 /*
@@ -2791,10 +2791,7 @@ static int handle_tx_event(struct xhci_hcd *xhci,
 
 	if (td && td->error_mid_td && !trb_in_td(xhci, td, ep_trb_dma, false)) {
 		xhci_dbg(xhci, "Missing TD completion event after mid TD error\n");
-		ep_ring->dequeue = td->end_trb;
-		ep_ring->deq_seg = td->end_seg;
-		inc_deq(xhci, ep_ring);
-		xhci_td_cleanup(xhci, td, ep_ring, td->status);
+		xhci_dequeue_td(xhci, td, ep_ring, td->status);
 	}
 
 	if (list_empty(&ep_ring->td_list)) {
-- 
2.51.0


From 804ef58a9e4ac65cb8168db7abde7a96b0da9e27 Mon Sep 17 00:00:00 2001
From: Niklas Neronin <niklas.neronin@linux.intel.com>
Date: Wed, 6 Nov 2024 12:14:56 +0200
Subject: [PATCH 16/16] usb: xhci: remove irrelevant comment

The code which it is referencing does not exist in the same function,
or the file for that matter. Since it was added [1], the Interrupter
Moderation Interval can be changed within xhci addon, e.g. PCI
xhci_pci_setup().

[1], commit 0ebbab374223 ("USB: xhci: Ring allocation and initialization.")

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20241106101459.775897-31-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci-mem.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 4295e9a4de50..15db90c54a45 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -2512,11 +2512,6 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
 
 	ir->isoc_bei_interval = AVOID_BEI_INTERVAL_MAX;
 
-	/*
-	 * XXX: Might need to set the Interrupter Moderation Register to
-	 * something other than the default (~1ms minimum between interrupts).
-	 * See section 5.5.1.2.
-	 */
 	for (i = 0; i < MAX_HC_SLOTS; i++)
 		xhci->devs[i] = NULL;
 
-- 
2.51.0