* [PATCH 0/3] usb: xhci: Add debug capability support in xhci
@ 2017-07-21 8:52 Lu Baolu
2017-07-21 8:52 ` [PATCH 1/3] usb: xhci: Make some static functions global Lu Baolu
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Lu Baolu @ 2017-07-21 8:52 UTC (permalink / raw)
To: Mathias Nyman, Greg Kroah-Hartman; +Cc: linux-usb, linux-kernel, Lu Baolu
Hi,
This series is for xHCI debug capability (spec section 7.6.8) support
in the xHCI driver.
xHCI compatible USB host controllers(i.e. super-speed USB3 controllers)
can be implemented with the Debug Capability(DbC). It presents a debug
device which is fully compliant with the USB framework and provides the
equivalent of a very high performance full-duplex serial link. The debug
capability operation model and registers interface are defined in 7.6.8
of the xHCI specification, revision 1.1.
The DbC debug device shares a root port with the xHCI host. By default,
the debug capability is disabled and the root port is assigned to xHCI.
When the DbC is enabled, the root port will be assigned to the DbC debug
device, and the xHCI sees nothing on this port. This implementation uses
a sysfs node named <dbc> under the xHCI device to manage the enabling
and disabling of the debug capability.
When the debug capability is enabled, it will present a debug device
through the debug port. This debug device is fully compliant with the
USB3 framework, and it can be enumerated by a debug host on the other
end of the USB link. As soon as the debug device is configured, a TTY
serial device named /dev/ttyGSn will be created.
One use of this link is running a login service on the debug target.
Hence it can be remote accessed by a debug host. Another use case can
probably be found in servers. It provides a peer-to-peer USB link
between two host-only machines. This provides a reasonable out-of-band
communication method between two servers.
Best regards,
Lu Baolu
Lu Baolu (3):
usb: xhci: Make some static functions global
usb: xhci: Add DbC support in xHCI driver
usb: doc: Update document for USB3 debug port usage
.../ABI/testing/sysfs-bus-pci-drivers-xhci_hcd | 25 +
Documentation/driver-api/usb/usb3-debug-port.rst | 68 ++
drivers/usb/host/Kconfig | 10 +
drivers/usb/host/Makefile | 5 +
drivers/usb/host/xhci-dbgcap.c | 1128 ++++++++++++++++++++
drivers/usb/host/xhci-mem.c | 94 +-
drivers/usb/host/xhci-ring.c | 4 +-
drivers/usb/host/xhci-trace.h | 64 ++
drivers/usb/host/xhci.c | 9 +
drivers/usb/host/xhci.h | 205 +++-
10 files changed, 1569 insertions(+), 43 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-bus-pci-drivers-xhci_hcd
create mode 100644 drivers/usb/host/xhci-dbgcap.c
--
2.7.4
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/3] usb: xhci: Make some static functions global
2017-07-21 8:52 [PATCH 0/3] usb: xhci: Add debug capability support in xhci Lu Baolu
@ 2017-07-21 8:52 ` Lu Baolu
2017-07-21 8:52 ` [PATCH 2/3] usb: xhci: Add DbC support in xHCI driver Lu Baolu
2017-07-21 8:52 ` [PATCH 3/3] usb: doc: Update document for USB3 debug port usage Lu Baolu
2 siblings, 0 replies; 6+ messages in thread
From: Lu Baolu @ 2017-07-21 8:52 UTC (permalink / raw)
To: Mathias Nyman, Greg Kroah-Hartman; +Cc: linux-usb, linux-kernel, Lu Baolu
This patch makes some static functions global to avoid duplications
in different files. These functions can be used in the implementation
of xHCI debug capability. There is no functional change.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
drivers/usb/host/xhci-mem.c | 94 ++++++++++++++++++++++++++------------------
drivers/usb/host/xhci-ring.c | 4 +-
drivers/usb/host/xhci.h | 16 +++++++-
3 files changed, 72 insertions(+), 42 deletions(-)
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 2a82c92..1ccb1c5 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -368,7 +368,7 @@ static int xhci_alloc_segments_for_ring(struct xhci_hcd *xhci,
* Set the end flag and the cycle toggle bit on the last segment.
* See section 4.9.1 and figures 15 and 16.
*/
-static struct xhci_ring *xhci_ring_alloc(struct xhci_hcd *xhci,
+struct xhci_ring *xhci_ring_alloc(struct xhci_hcd *xhci,
unsigned int num_segs, unsigned int cycle_state,
enum xhci_ring_type type, unsigned int max_packet, gfp_t flags)
{
@@ -467,7 +467,7 @@ int xhci_ring_expansion(struct xhci_hcd *xhci, struct xhci_ring *ring,
#define CTX_SIZE(_hcc) (HCC_64BYTE_CONTEXT(_hcc) ? 64 : 32)
-static struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci,
+struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci,
int type, gfp_t flags)
{
struct xhci_container_ctx *ctx;
@@ -492,7 +492,7 @@ static struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci
return ctx;
}
-static void xhci_free_container_ctx(struct xhci_hcd *xhci,
+void xhci_free_container_ctx(struct xhci_hcd *xhci,
struct xhci_container_ctx *ctx)
{
if (!ctx)
@@ -1762,21 +1762,61 @@ void xhci_free_command(struct xhci_hcd *xhci,
kfree(command);
}
+int xhci_alloc_erst(struct xhci_hcd *xhci,
+ struct xhci_ring *evt_ring,
+ struct xhci_erst *erst,
+ gfp_t flags)
+{
+ size_t size;
+ unsigned int val;
+ struct xhci_segment *seg;
+ struct xhci_erst_entry *entry;
+
+ size = sizeof(struct xhci_erst_entry) * evt_ring->num_segs;
+ erst->entries = dma_alloc_coherent(xhci_to_hcd(xhci)->self.sysdev,
+ size,
+ &erst->erst_dma_addr,
+ flags);
+ if (!erst->entries)
+ return -ENOMEM;
+
+ memset(erst->entries, 0, size);
+ erst->num_entries = evt_ring->num_segs;
+
+ seg = evt_ring->first_seg;
+ for (val = 0; val < evt_ring->num_segs; val++) {
+ entry = &erst->entries[val];
+ entry->seg_addr = cpu_to_le64(seg->dma);
+ entry->seg_size = cpu_to_le32(TRBS_PER_SEGMENT);
+ entry->rsvd = 0;
+ seg = seg->next;
+ }
+
+ return 0;
+}
+
+void xhci_free_erst(struct xhci_hcd *xhci, struct xhci_erst *erst)
+{
+ size_t size;
+ struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
+
+ size = sizeof(struct xhci_erst_entry) * (erst->num_entries);
+ if (erst->entries)
+ dma_free_coherent(dev, size,
+ erst->entries,
+ erst->erst_dma_addr);
+ erst->entries = NULL;
+}
+
void xhci_mem_cleanup(struct xhci_hcd *xhci)
{
struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
- int size;
int i, j, num_ports;
cancel_delayed_work_sync(&xhci->cmd_timer);
- /* Free the Event Ring Segment Table and the actual Event Ring */
- size = sizeof(struct xhci_erst_entry)*(xhci->erst.num_entries);
- if (xhci->erst.entries)
- dma_free_coherent(dev, size,
- xhci->erst.entries, xhci->erst.erst_dma_addr);
- xhci->erst.entries = NULL;
- xhci_dbg_trace(xhci, trace_xhci_dbg_init, "Freed ERST");
+ xhci_free_erst(xhci, &xhci->erst);
+
if (xhci->event_ring)
xhci_ring_free(xhci, xhci->event_ring);
xhci->event_ring = NULL;
@@ -2313,9 +2353,8 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
unsigned int val, val2;
u64 val_64;
- struct xhci_segment *seg;
- u32 page_size, temp;
- int i;
+ u32 page_size, temp;
+ int i, ret;
INIT_LIST_HEAD(&xhci->cmd_list);
@@ -2454,32 +2493,9 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
if (xhci_check_trb_in_td_math(xhci) < 0)
goto fail;
- xhci->erst.entries = dma_alloc_coherent(dev,
- sizeof(struct xhci_erst_entry) * ERST_NUM_SEGS, &dma,
- flags);
- if (!xhci->erst.entries)
+ ret = xhci_alloc_erst(xhci, xhci->event_ring, &xhci->erst, flags);
+ if (ret)
goto fail;
- xhci_dbg_trace(xhci, trace_xhci_dbg_init,
- "// Allocated event ring segment table at 0x%llx",
- (unsigned long long)dma);
-
- memset(xhci->erst.entries, 0, sizeof(struct xhci_erst_entry)*ERST_NUM_SEGS);
- xhci->erst.num_entries = ERST_NUM_SEGS;
- xhci->erst.erst_dma_addr = dma;
- xhci_dbg_trace(xhci, trace_xhci_dbg_init,
- "Set ERST to 0; private num segs = %i, virt addr = %p, dma addr = 0x%llx",
- xhci->erst.num_entries,
- xhci->erst.entries,
- (unsigned long long)xhci->erst.erst_dma_addr);
-
- /* set ring base address and size for each segment table entry */
- for (val = 0, seg = xhci->event_ring->first_seg; val < ERST_NUM_SEGS; val++) {
- struct xhci_erst_entry *entry = &xhci->erst.entries[val];
- entry->seg_addr = cpu_to_le64(seg->dma);
- entry->seg_size = cpu_to_le32(TRBS_PER_SEGMENT);
- entry->rsvd = 0;
- seg = seg->next;
- }
/* set ERST count with the number of entries in the segment table */
val = readl(&xhci->ir_set->erst_size);
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index c50c902..6e73645 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -165,7 +165,7 @@ static void next_trb(struct xhci_hcd *xhci,
* See Cycle bit rules. SW is the consumer for the event ring only.
* Don't make a ring full of link TRBs. That would be dumb and this would loop.
*/
-static void inc_deq(struct xhci_hcd *xhci, struct xhci_ring *ring)
+void inc_deq(struct xhci_hcd *xhci, struct xhci_ring *ring)
{
/* event ring doesn't have link trbs, check for last trb */
if (ring->type == TYPE_EVENT) {
@@ -2958,7 +2958,7 @@ static int prepare_transfer(struct xhci_hcd *xhci,
return 0;
}
-static unsigned int count_trbs(u64 addr, u64 len)
+unsigned int count_trbs(u64 addr, u64 len)
{
unsigned int num_trbs;
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 3c6da1f..b4a9b24 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1958,9 +1958,17 @@ void xhci_slot_copy(struct xhci_hcd *xhci,
int xhci_endpoint_init(struct xhci_hcd *xhci, struct xhci_virt_device *virt_dev,
struct usb_device *udev, struct usb_host_endpoint *ep,
gfp_t mem_flags);
+struct xhci_ring *xhci_ring_alloc(struct xhci_hcd *xhci,
+ unsigned int num_segs, unsigned int cycle_state,
+ enum xhci_ring_type type, unsigned int max_packet, gfp_t flags);
void xhci_ring_free(struct xhci_hcd *xhci, struct xhci_ring *ring);
int xhci_ring_expansion(struct xhci_hcd *xhci, struct xhci_ring *ring,
- unsigned int num_trbs, gfp_t flags);
+ unsigned int num_trbs, gfp_t flags);
+int xhci_alloc_erst(struct xhci_hcd *xhci,
+ struct xhci_ring *evt_ring,
+ struct xhci_erst *erst,
+ gfp_t flags);
+void xhci_free_erst(struct xhci_hcd *xhci, struct xhci_erst *erst);
void xhci_free_endpoint_ring(struct xhci_hcd *xhci,
struct xhci_virt_device *virt_dev,
unsigned int ep_index);
@@ -1990,6 +1998,10 @@ struct xhci_command *xhci_alloc_command(struct xhci_hcd *xhci,
void xhci_urb_free_priv(struct urb_priv *urb_priv);
void xhci_free_command(struct xhci_hcd *xhci,
struct xhci_command *command);
+struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci,
+ int type, gfp_t flags);
+void xhci_free_container_ctx(struct xhci_hcd *xhci,
+ struct xhci_container_ctx *ctx);
/* xHCI host controller glue */
typedef void (*xhci_get_quirks_t)(struct device *, struct xhci_hcd *);
@@ -2064,6 +2076,8 @@ void xhci_handle_command_timeout(struct work_struct *work);
void xhci_ring_ep_doorbell(struct xhci_hcd *xhci, unsigned int slot_id,
unsigned int ep_index, unsigned int stream_id);
void xhci_cleanup_command_queue(struct xhci_hcd *xhci);
+void inc_deq(struct xhci_hcd *xhci, struct xhci_ring *ring);
+unsigned int count_trbs(u64 addr, u64 len);
/* xHCI roothub code */
void xhci_set_link_state(struct xhci_hcd *xhci, __le32 __iomem **port_array,
--
2.7.4
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 2/3] usb: xhci: Add DbC support in xHCI driver
2017-07-21 8:52 [PATCH 0/3] usb: xhci: Add debug capability support in xhci Lu Baolu
2017-07-21 8:52 ` [PATCH 1/3] usb: xhci: Make some static functions global Lu Baolu
@ 2017-07-21 8:52 ` Lu Baolu
2017-07-21 10:31 ` Felipe Balbi
2017-07-21 8:52 ` [PATCH 3/3] usb: doc: Update document for USB3 debug port usage Lu Baolu
2 siblings, 1 reply; 6+ messages in thread
From: Lu Baolu @ 2017-07-21 8:52 UTC (permalink / raw)
To: Mathias Nyman, Greg Kroah-Hartman; +Cc: linux-usb, linux-kernel, Lu Baolu
xHCI compatible USB host controllers(i.e. super-speed USB3 controllers)
can be implemented with the Debug Capability(DbC). It presents a debug
device which is fully compliant with the USB framework and provides the
equivalent of a very high performance full-duplex serial link. The debug
capability operation model and registers interface are defined in 7.6.8
of the xHCI specification, revision 1.1.
The DbC debug device shares a root port with the xHCI host. By default,
the debug capability is disabled and the root port is assigned to xHCI.
When the DbC is enabled, the root port will be assigned to the DbC debug
device, and the xHCI sees nothing on this port. This implementation uses
a sysfs node named <dbc> under the xHCI device to manage the enabling
and disabling of the debug capability.
When the debug capability is enabled, it will present a debug device
through the debug port. This debug device is fully compliant with the
USB3 framework, and it can be enumerated by a debug host on the other
end of the USB link. As soon as the debug device is configured, a TTY
serial device named /dev/ttyGSn will be created.
One use of this link is running a login service on the debug target.
Hence it can be remote accessed by a debug host. Another use case can
probably be found in servers. It provides a peer-to-peer USB link
between two host-only machines. This provides a reasonable out-of-band
communication method between two servers.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
.../ABI/testing/sysfs-bus-pci-drivers-xhci_hcd | 25 +
drivers/usb/host/Kconfig | 10 +
drivers/usb/host/Makefile | 5 +
drivers/usb/host/xhci-dbgcap.c | 1128 ++++++++++++++++++++
drivers/usb/host/xhci-trace.h | 64 ++
drivers/usb/host/xhci.c | 9 +
drivers/usb/host/xhci.h | 189 +++-
7 files changed, 1429 insertions(+), 1 deletion(-)
create mode 100644 Documentation/ABI/testing/sysfs-bus-pci-drivers-xhci_hcd
create mode 100644 drivers/usb/host/xhci-dbgcap.c
diff --git a/Documentation/ABI/testing/sysfs-bus-pci-drivers-xhci_hcd b/Documentation/ABI/testing/sysfs-bus-pci-drivers-xhci_hcd
new file mode 100644
index 0000000..0088aba
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-pci-drivers-xhci_hcd
@@ -0,0 +1,25 @@
+What: /sys/bus/pci/drivers/xhci_hcd/.../dbc
+Date: June 2017
+Contact: Lu Baolu <baolu.lu@linux.intel.com>
+Description:
+ xHCI compatible USB host controllers (i.e. super-speed
+ USB3 controllers) are often implemented with the Debug
+ Capability (DbC). It can present a debug device which
+ is fully compliant with the USB framework and provides
+ the equivalent of a very high performance full-duplex
+ serial link for debug purpose.
+
+ The DbC debug device shares a root port with xHCI host.
+ When the DbC is enabled, the root port will be assigned
+ to the Debug Capability. Otherwise, it will be assigned
+ to xHCI.
+
+ Writing "enable" to this attribute will enable the DbC
+ functionality and the shared root port will be assigned
+ to the DbC device. Writing "disable" to this attribute
+ will disable the DbC functionality and the shared root
+ port will roll back to the xHCI.
+
+ Reading this attribute gives the state of the DbC. It
+ can be one of the following states: disabled, enabled,
+ initialized, connected, configured and stalled.
diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index fa5692d..cfb2450 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -27,6 +27,16 @@ config USB_XHCI_HCD
module will be called xhci-hcd.
if USB_XHCI_HCD
+config USB_XHCI_DBGCAP
+ bool "xHCI support for debug capability"
+ depends on TTY
+ depends on USB_GADGET=y
+ select USB_U_SERIAL
+ ---help---
+ Say 'Y' to enable the support for the xHCI debug capability. Make
+ sure that your xHCI host supports the extended debug capability and
+ you want a TTY serial device based on the xHCI debug capability
+ before enabling this option. If unsure, say 'N'.
config USB_XHCI_PCI
tristate
diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile
index cf2691f..4629d20 100644
--- a/drivers/usb/host/Makefile
+++ b/drivers/usb/host/Makefile
@@ -13,6 +13,11 @@ fhci-$(CONFIG_FHCI_DEBUG) += fhci-dbg.o
xhci-hcd-y := xhci.o xhci-mem.o
xhci-hcd-y += xhci-ring.o xhci-hub.o xhci-dbg.o
xhci-hcd-y += xhci-trace.o
+
+ifneq ($(CONFIG_USB_XHCI_DBGCAP), )
+ xhci-hcd-y += xhci-dbgcap.o
+endif
+
ifneq ($(CONFIG_USB_XHCI_MTK), )
xhci-hcd-y += xhci-mtk-sch.o
endif
diff --git a/drivers/usb/host/xhci-dbgcap.c b/drivers/usb/host/xhci-dbgcap.c
new file mode 100644
index 0000000..250f652
--- /dev/null
+++ b/drivers/usb/host/xhci-dbgcap.c
@@ -0,0 +1,1128 @@
+/**
+ * xhci-dbgcap.c - xHCI debug capability support
+ *
+ * Copyright (C) 2017 Intel Corporation
+ *
+ * Author: Lu Baolu <baolu.lu@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+
+#include "xhci.h"
+#include "xhci-trace.h"
+
+static inline void *
+dbc_dma_alloc_coherent(struct xhci_hcd *xhci, size_t size,
+ dma_addr_t *dma_handle, gfp_t flags)
+{
+ void *vaddr;
+
+ vaddr = dma_alloc_coherent(xhci_to_hcd(xhci)->self.sysdev,
+ size, dma_handle, flags);
+ memset(vaddr, 0, size);
+ return vaddr;
+}
+
+static inline void
+dbc_dma_free_coherent(struct xhci_hcd *xhci, size_t size,
+ void *cpu_addr, dma_addr_t dma_handle)
+{
+ if (cpu_addr)
+ dma_free_coherent(xhci_to_hcd(xhci)->self.sysdev,
+ size, cpu_addr, dma_handle);
+}
+
+static inline void xhci_put_utf16(u16 *s, const char *c)
+{
+ int i;
+ size_t size;
+
+ size = strlen(c);
+ for (i = 0; i < size; i++)
+ s[i] = cpu_to_le16(c[i]);
+}
+
+static u32 xhci_dbc_populate_strings(struct dbc_strings *strings)
+{
+ struct usb_string_descriptor *s_desc;
+ u32 string_length;
+
+ /* Serial string: */
+ s_desc = (struct usb_string_descriptor *)strings->serial;
+ xhci_put_utf16(s_desc->wData, DBC_STRING_SERIAL);
+
+ s_desc->bLength = (strlen(DBC_STRING_SERIAL) + 1) * 2;
+ s_desc->bDescriptorType = USB_DT_STRING;
+ string_length = s_desc->bLength;
+ string_length <<= 8;
+
+ /* Product string: */
+ s_desc = (struct usb_string_descriptor *)strings->product;
+ xhci_put_utf16(s_desc->wData, DBC_STRING_PRODUCT);
+
+ s_desc->bLength = (strlen(DBC_STRING_PRODUCT) + 1) * 2;
+ s_desc->bDescriptorType = USB_DT_STRING;
+ string_length += s_desc->bLength;
+ string_length <<= 8;
+
+ /* Manufacture string: */
+ s_desc = (struct usb_string_descriptor *)strings->manufacturer;
+ xhci_put_utf16(s_desc->wData, DBC_STRING_MANUFACTURER);
+
+ s_desc->bLength = (strlen(DBC_STRING_MANUFACTURER) + 1) * 2;
+ s_desc->bDescriptorType = USB_DT_STRING;
+ string_length += s_desc->bLength;
+ string_length <<= 8;
+
+ /* String0: */
+ strings->string0[0] = 4;
+ strings->string0[1] = USB_DT_STRING;
+ strings->string0[2] = 0x09;
+ strings->string0[3] = 0x04;
+ string_length += 4;
+
+ return string_length;
+}
+
+static void xhci_dbc_populate_contexts(struct xhci_hcd *xhci, u32 string_length)
+{
+ struct xhci_dbc *dbc;
+ struct dbc_info_context *info;
+ struct xhci_ep_ctx *ep_ctx;
+ u32 dev_info;
+ dma_addr_t deq, dma;
+ unsigned int max_burst;
+
+ dbc = xhci->dbc;
+ if (!dbc)
+ return;
+
+ /* Populate info Context: */
+ info = (struct dbc_info_context *)dbc->ctx->bytes;
+ dma = dbc->string_dma;
+ info->string0 = cpu_to_le64(dma);
+ info->manufacturer = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH);
+ info->product = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH * 2);
+ info->serial = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH * 3);
+ info->length = cpu_to_le32(string_length);
+
+ /* Populate bulk out endpoint context: */
+ ep_ctx = dbc_bulkout_ctx(dbc);
+ max_burst = DBC_CTRL_MAXBURST(readl(&dbc->regs->control));
+ deq = dbc_bulkout_enq(dbc);
+ ep_ctx->ep_info = 0;
+ ep_ctx->ep_info2 = dbc_epctx_info2(BULK_OUT_EP, 1024, max_burst);
+ ep_ctx->deq = cpu_to_le64(deq | dbc->ring_out->cycle_state);
+
+ /* Populate bulk in endpoint context: */
+ ep_ctx = dbc_bulkin_ctx(dbc);
+ deq = dbc_bulkin_enq(dbc);
+ ep_ctx->ep_info = 0;
+ ep_ctx->ep_info2 = dbc_epctx_info2(BULK_IN_EP, 1024, max_burst);
+ ep_ctx->deq = cpu_to_le64(deq | dbc->ring_in->cycle_state);
+
+ /* Set DbC context and info registers: */
+ xhci_write_64(xhci, dbc->ctx->dma, &dbc->regs->dccp);
+
+ dev_info = cpu_to_le32((DBC_VENDOR_ID << 16) | DBC_PROTOCOL);
+ writel(dev_info, &dbc->regs->devinfo1);
+
+ dev_info = cpu_to_le32((DBC_DEVICE_REV << 16) | DBC_PRODUCT_ID);
+ writel(dev_info, &dbc->regs->devinfo2);
+}
+
+static void xhci_dbc_giveback(struct dbc_request *dreq, int status)
+ __releases(&dbc->lock)
+ __acquires(&dbc->lock)
+{
+ struct dbc_ep *dep = dreq->dep;
+ struct usb_request *req = &dreq->request;
+ struct xhci_dbc *dbc = dep->dbc;
+ struct device *dev = xhci_to_hcd(dbc->xhci)->self.sysdev;
+
+ list_del_init(&dreq->list);
+ dreq->trb_dma = 0;
+ dreq->trb = NULL;
+
+ if (req->status == -EINPROGRESS)
+ req->status = status;
+
+ dma_unmap_single(dev,
+ req->dma,
+ req->length,
+ dbc_ep_dma_direction(dep));
+
+ /* Give back the transfer request: */
+ trace_xhci_dbc_giveback_request(dreq);
+ spin_unlock(&dbc->lock);
+ req->complete(&dep->ep, req);
+ spin_lock(&dbc->lock);
+}
+
+static void xhci_dbc_flush_single_request(struct dbc_request *dreq)
+{
+ union xhci_trb *trb = dreq->trb;
+
+ trb->generic.field[0] = 0;
+ trb->generic.field[1] = 0;
+ trb->generic.field[2] = 0;
+ trb->generic.field[3] &= cpu_to_le32(TRB_CYCLE);
+ trb->generic.field[3] |= cpu_to_le32(TRB_TYPE(TRB_TR_NOOP));
+
+ xhci_dbc_giveback(dreq, -ECONNRESET);
+}
+
+static void xhci_dbc_flush_endpoint_requests(struct dbc_ep *dep)
+{
+ struct dbc_request *dreq, *tmp;
+
+ list_for_each_entry_safe(dreq, tmp, &dep->pending_list, list)
+ xhci_dbc_flush_single_request(dreq);
+}
+
+static void xhci_dbc_flush_reqests(struct xhci_dbc *dbc)
+{
+ int i;
+ struct dbc_ep *dep;
+
+ for (i = BULK_OUT; i <= BULK_IN; i++) {
+ dep = dbc->eps[i];
+ xhci_dbc_flush_endpoint_requests(dep);
+ }
+}
+
+static int dbc_gadget_ep_enable(struct usb_ep *ep,
+ const struct usb_endpoint_descriptor *desc)
+{
+ struct dbc_ep *dep = ep_to_dep(ep);
+ struct xhci_dbc *dbc = dep->dbc;
+
+ return dbc->state == DS_CONFIGURED;
+}
+
+static int dbc_gadget_ep_disable(struct usb_ep *ep)
+{
+ struct dbc_ep *dep = ep_to_dep(ep);
+ struct xhci_dbc *dbc = dep->dbc;
+
+ spin_lock(&dbc->lock);
+ xhci_dbc_flush_reqests(dbc);
+ spin_unlock(&dbc->lock);
+
+ return 0;
+}
+
+static struct usb_request *
+dbc_gadget_ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
+{
+ struct dbc_request *dreq;
+ struct dbc_ep *dep = ep_to_dep(ep);
+
+ dreq = kzalloc(sizeof(*dreq), gfp_flags);
+ if (!dreq)
+ return NULL;
+
+ dreq->dep = dep;
+ INIT_LIST_HEAD(&dreq->list);
+
+ trace_xhci_dbc_alloc_request(dreq);
+
+ return &dreq->request;
+}
+
+static void
+dbc_gadget_ep_free_request(struct usb_ep *ep, struct usb_request *request)
+{
+ struct dbc_request *dreq = req_to_dreq(request);
+
+ trace_xhci_dbc_free_request(dreq);
+
+ kfree(dreq);
+}
+
+static void
+xhci_dbc_queue_trb(struct xhci_ring *ring, u32 field1,
+ u32 field2, u32 field3, u32 field4)
+{
+ union xhci_trb *trb, *next;
+
+ trb = ring->enqueue;
+ trb->generic.field[0] = cpu_to_le32(field1);
+ trb->generic.field[1] = cpu_to_le32(field2);
+ trb->generic.field[2] = cpu_to_le32(field3);
+ trb->generic.field[3] = cpu_to_le32(field4);
+
+ trace_xhci_dbc_gadget_ep_queue(ring, &trb->generic);
+
+ ring->num_trbs_free--;
+ next = ++(ring->enqueue);
+ if (TRB_TYPE_LINK_LE32(next->link.control)) {
+ next->link.control ^= cpu_to_le32(TRB_CYCLE);
+ ring->enqueue = ring->enq_seg->trbs;
+ ring->cycle_state ^= 1;
+ }
+}
+
+static int xhci_dbc_queue_bulk_tx(struct dbc_ep *dep,
+ struct dbc_request *dreq)
+{
+ u64 addr;
+ union xhci_trb *trb;
+ unsigned int num_trbs;
+ struct xhci_dbc *dbc = dep->dbc;
+ struct xhci_ring *ring = dep->ring;
+ struct usb_request *req = &dreq->request;
+ u32 length, control, cycle;
+
+ num_trbs = count_trbs(req->dma, req->length);
+ WARN_ON(num_trbs != 1);
+ if (ring->num_trbs_free < num_trbs)
+ return -EBUSY;
+
+ addr = req->dma;
+ trb = ring->enqueue;
+ cycle = ring->cycle_state;
+ length = TRB_LEN(req->length);
+ control = TRB_TYPE(TRB_NORMAL) | TRB_IOC;
+
+ if (cycle)
+ control &= cpu_to_le32(~TRB_CYCLE);
+ else
+ control |= cpu_to_le32(TRB_CYCLE);
+
+ dreq->trb = ring->enqueue;
+ dreq->trb_dma = xhci_trb_virt_to_dma(ring->enq_seg, ring->enqueue);
+ xhci_dbc_queue_trb(ring,
+ lower_32_bits(addr),
+ upper_32_bits(addr),
+ length, control);
+
+ /*
+ * Add a barrier between writes of trb fields and flipping
+ * the cycle bit:
+ */
+ wmb();
+
+ if (cycle)
+ trb->generic.field[3] |= cpu_to_le32(TRB_CYCLE);
+ else
+ trb->generic.field[3] &= cpu_to_le32(~TRB_CYCLE);
+
+ writel(DBC_DOOR_BELL_TARGET(dep->direction), &dbc->regs->doorbell);
+
+ return 0;
+}
+
+static int
+__dbc_gadget_ep_queue(struct dbc_ep *dep, struct dbc_request *dreq)
+{
+ int ret;
+ struct device *dev;
+ struct xhci_dbc *dbc = dep->dbc;
+ struct xhci_hcd *xhci = dbc->xhci;
+ struct usb_request *req = &dreq->request;
+
+ dev = xhci_to_hcd(xhci)->self.sysdev;
+
+ req->actual = 0;
+ req->status = -EINPROGRESS;
+
+ if (!req->length || !req->buf)
+ return -EINVAL;
+
+ req->dma = dma_map_single(dev,
+ req->buf,
+ req->length,
+ dbc_ep_dma_direction(dep));
+ if (dma_mapping_error(dev, req->dma)) {
+ xhci_err(xhci, "failed to map buffer\n");
+ return -EFAULT;
+ }
+
+ ret = xhci_dbc_queue_bulk_tx(dep, dreq);
+ if (ret) {
+ xhci_err(xhci, "failed to queue trbs\n");
+ dma_unmap_single(dev,
+ req->dma,
+ req->length,
+ dbc_ep_dma_direction(dep));
+ return -EFAULT;
+ }
+
+ list_add_tail(&dreq->list, &dep->pending_list);
+
+ return 0;
+}
+
+static int dbc_gadget_ep_queue(struct usb_ep *ep,
+ struct usb_request *request,
+ gfp_t gfp_flags)
+{
+ struct dbc_request *dreq = req_to_dreq(request);
+ struct dbc_ep *dep = ep_to_dep(ep);
+ struct xhci_dbc *dbc = dep->dbc;
+ int ret = -ECONNRESET;
+
+ spin_lock(&dbc->lock);
+ if (dbc->state == DS_CONFIGURED) {
+ ret = __dbc_gadget_ep_queue(dep, dreq);
+ trace_xhci_dbc_queue_request(dreq);
+ }
+ spin_unlock(&dbc->lock);
+
+ return ret;
+}
+
+static int dbc_gadget_ep_dequeue(struct usb_ep *ep,
+ struct usb_request *request)
+{
+ struct dbc_request *dreq = req_to_dreq(request);
+ struct dbc_ep *dep = ep_to_dep(ep);
+ struct xhci_dbc *dbc = dep->dbc;
+
+ trace_xhci_dbc_dequeue_request(dreq);
+
+ spin_lock(&dbc->lock);
+ xhci_dbc_flush_single_request(dreq);
+ spin_unlock(&dbc->lock);
+
+ return 0;
+}
+
+static int dbc_gadget_ep_set_halt(struct usb_ep *ep, int value)
+{
+ return 0;
+}
+
+static int dbc_gadget_ep_set_wedge(struct usb_ep *ep)
+{
+ return 0;
+}
+
+static const struct usb_ep_ops xhci_dbc_gadget_ep_ops = {
+ .enable = dbc_gadget_ep_enable,
+ .disable = dbc_gadget_ep_disable,
+ .alloc_request = dbc_gadget_ep_alloc_request,
+ .free_request = dbc_gadget_ep_free_request,
+ .queue = dbc_gadget_ep_queue,
+ .dequeue = dbc_gadget_ep_dequeue,
+ .set_halt = dbc_gadget_ep_set_halt,
+ .set_wedge = dbc_gadget_ep_set_wedge,
+};
+
+static inline struct dbc_ep *
+xhci_dbc_alloc_endpoint(struct xhci_hcd *xhci, bool direction)
+{
+ struct usb_ep *ep;
+ struct dbc_ep *dep;
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ dep = kzalloc(sizeof(*dep), GFP_KERNEL);
+ if (!dep)
+ return NULL;
+
+ ep = &dep->ep;
+ ep->name = direction ? "ep-dbc-in" : "ep-dbc-out";
+ ep->ops = &xhci_dbc_gadget_ep_ops;
+ ep->caps.type_bulk = 1;
+ ep->caps.dir_in = !direction;
+ ep->caps.dir_out = direction;
+ ep->maxpacket = DBC_MAX_PACKET;
+ ep->maxpacket_limit = DBC_MAX_PACKET;
+ ep->maxburst = DBC_CTRL_MAXBURST(readl(&dbc->regs->control));
+ dep->dbc = dbc;
+ dep->direction = direction;
+ dep->ring = direction ? dbc->ring_in : dbc->ring_out;
+
+ INIT_LIST_HEAD(&dep->pending_list);
+
+ return dep;
+}
+
+static int xhci_dbc_gadget_eps_init(struct xhci_hcd *xhci)
+{
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ dbc->eps[BULK_OUT] = xhci_dbc_alloc_endpoint(xhci, BULK_OUT);
+ dbc->eps[BULK_IN] = xhci_dbc_alloc_endpoint(xhci, BULK_IN);
+
+ if (!dbc->eps[BULK_OUT] || !dbc->eps[BULK_IN]) {
+ kfree(dbc->eps[BULK_OUT]);
+ kfree(dbc->eps[BULK_IN]);
+
+ return -ENOMEM;
+ }
+
+ dbc->gs_port.in = &dbc->eps[BULK_OUT]->ep;
+ dbc->gs_port.out = &dbc->eps[BULK_IN]->ep;
+
+ return 0;
+}
+
+static void xhci_dbc_gadget_eps_exit(struct xhci_hcd *xhci)
+{
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ kfree(dbc->gs_port.in);
+ kfree(dbc->gs_port.out);
+}
+
+static int xhci_dbc_mem_init(struct xhci_hcd *xhci, gfp_t flags)
+{
+ int ret;
+ dma_addr_t deq;
+ u32 string_length;
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ /* Allocate various rings for events and transfers: */
+ dbc->ring_evt = xhci_ring_alloc(xhci, 1, 1, TYPE_EVENT, 0, flags);
+ if (!dbc->ring_evt)
+ goto evt_fail;
+
+ dbc->ring_in = xhci_ring_alloc(xhci, 1, 1, TYPE_BULK, 0, flags);
+ if (!dbc->ring_in)
+ goto in_fail;
+
+ dbc->ring_out = xhci_ring_alloc(xhci, 1, 1, TYPE_BULK, 0, flags);
+ if (!dbc->ring_out)
+ goto out_fail;
+
+ /* Allocate and populate ERST: */
+ ret = xhci_alloc_erst(xhci, dbc->ring_evt, &dbc->erst, flags);
+ if (ret)
+ goto erst_fail;
+
+ /* Allocate context data structure: */
+ dbc->ctx = xhci_alloc_container_ctx(xhci, XHCI_CTX_TYPE_DEVICE, flags);
+ if (!dbc->ctx)
+ goto ctx_fail;
+
+ /* Allocate the string table: */
+ dbc->string_size = sizeof(struct dbc_strings);
+ dbc->string = dbc_dma_alloc_coherent(xhci,
+ dbc->string_size,
+ &dbc->string_dma,
+ flags);
+ if (!dbc->string)
+ goto string_fail;
+
+ /* Setup ERST register: */
+ writel(dbc->erst.erst_size, &dbc->regs->ersts);
+ xhci_write_64(xhci, dbc->erst.erst_dma_addr, &dbc->regs->erstba);
+ deq = xhci_trb_virt_to_dma(dbc->ring_evt->deq_seg,
+ dbc->ring_evt->dequeue);
+ xhci_write_64(xhci, deq, &dbc->regs->erdp);
+
+ /* Setup strings and contexts: */
+ string_length = xhci_dbc_populate_strings(dbc->string);
+ xhci_dbc_populate_contexts(xhci, string_length);
+
+ mmiowb();
+
+ ret = xhci_dbc_gadget_eps_init(xhci);
+ if (ret)
+ goto eps_init_fail;
+
+ dbc->state = DS_INITIALIZED;
+
+ return 0;
+
+eps_init_fail:
+ dbc_dma_free_coherent(xhci,
+ dbc->string_size,
+ dbc->string, dbc->string_dma);
+ dbc->string = NULL;
+string_fail:
+ xhci_free_container_ctx(xhci, dbc->ctx);
+ dbc->ctx = NULL;
+ctx_fail:
+ xhci_free_erst(xhci, &dbc->erst);
+erst_fail:
+ xhci_ring_free(xhci, dbc->ring_out);
+ dbc->ring_out = NULL;
+out_fail:
+ xhci_ring_free(xhci, dbc->ring_in);
+ dbc->ring_in = NULL;
+in_fail:
+ xhci_ring_free(xhci, dbc->ring_evt);
+ dbc->ring_evt = NULL;
+evt_fail:
+ return -ENOMEM;
+}
+
+static void xhci_dbc_mem_cleanup(struct xhci_hcd *xhci)
+{
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ if (!dbc)
+ return;
+
+ xhci_dbc_gadget_eps_exit(xhci);
+
+ if (dbc->string) {
+ dbc_dma_free_coherent(xhci,
+ dbc->string_size,
+ dbc->string, dbc->string_dma);
+ dbc->string = NULL;
+ }
+
+ xhci_free_container_ctx(xhci, dbc->ctx);
+ dbc->ctx = NULL;
+
+ xhci_free_erst(xhci, &dbc->erst);
+ xhci_ring_free(xhci, dbc->ring_out);
+ xhci_ring_free(xhci, dbc->ring_in);
+ xhci_ring_free(xhci, dbc->ring_evt);
+ dbc->ring_in = NULL;
+ dbc->ring_out = NULL;
+ dbc->ring_evt = NULL;
+}
+
+static void xhci_dbc_reset_debug_port(struct xhci_hcd *xhci)
+{
+ u32 val;
+ unsigned long flags;
+ int port_index;
+ __le32 __iomem **port_array;
+
+ spin_lock_irqsave(&xhci->lock, flags);
+
+ port_index = xhci->num_usb3_ports;
+ port_array = xhci->usb3_ports;
+ if (port_index <= 0) {
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ return;
+ }
+
+ while (port_index--) {
+ val = readl(port_array[port_index]);
+ if (!(val & PORT_CONNECT))
+ writel(val | PORT_RESET, port_array[port_index]);
+ }
+
+ spin_unlock_irqrestore(&xhci->lock, flags);
+}
+
+static int __xhci_dbc_start(struct xhci_hcd *xhci)
+{
+ int ret;
+ u32 ctrl;
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ if (dbc->state != DS_DISABLED)
+ return -EINVAL;
+
+ writel(0, &dbc->regs->control);
+ ret = xhci_handshake(&dbc->regs->control,
+ DBC_CTRL_DBC_ENABLE,
+ 0, 1000);
+ if (ret)
+ return ret;
+
+ ret = xhci_dbc_mem_init(xhci, GFP_KERNEL);
+ if (ret)
+ return ret;
+
+ ctrl = readl(&dbc->regs->control);
+ writel(ctrl | DBC_CTRL_DBC_ENABLE | DBC_CTRL_PORT_ENABLE,
+ &dbc->regs->control);
+ ret = xhci_handshake(&dbc->regs->control,
+ DBC_CTRL_DBC_ENABLE,
+ DBC_CTRL_DBC_ENABLE, 1000);
+ if (ret)
+ return ret;
+
+ xhci_dbc_reset_debug_port(xhci);
+ dbc->state = DS_ENABLED;
+
+ return 0;
+}
+
+static void __xhci_dbc_stop(struct xhci_hcd *xhci)
+{
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ if (dbc->state == DS_DISABLED)
+ return;
+
+ writel(0, &dbc->regs->control);
+ xhci_dbc_mem_cleanup(xhci);
+ dbc->state = DS_DISABLED;
+}
+
+static int xhci_dbc_start(struct xhci_hcd *xhci)
+{
+ int ret;
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ WARN_ON(!dbc);
+
+ spin_lock(&dbc->lock);
+ ret = __xhci_dbc_start(xhci);
+ spin_unlock(&dbc->lock);
+
+ if (!ret) {
+ pm_runtime_get_sync(xhci_to_hcd(xhci)->self.controller);
+ ret = mod_delayed_work(system_wq, &dbc->event_work, 1);
+ }
+
+ return ret;
+}
+
+static void xhci_dbc_stop(struct xhci_hcd *xhci)
+{
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ WARN_ON(!dbc);
+
+ cancel_delayed_work_sync(&dbc->event_work);
+
+ if (dbc->gs_port_num != GSPORT_INVAL) {
+ gserial_disconnect(&dbc->gs_port);
+ gserial_free_line(dbc->gs_port_num);
+ dbc->gs_port_num = GSPORT_INVAL;
+ }
+
+ spin_lock(&dbc->lock);
+ __xhci_dbc_stop(xhci);
+ spin_unlock(&dbc->lock);
+
+ pm_runtime_put_sync(xhci_to_hcd(xhci)->self.controller);
+}
+
+static void
+dbc_handle_port_status(struct xhci_hcd *xhci, union xhci_trb *event)
+{
+ u32 portsc;
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ portsc = readl(&dbc->regs->portsc);
+ if (portsc & DBC_PORTSC_CONN_CHANGE)
+ xhci_info(xhci, "DbC port connect change\n");
+
+ if (portsc & DBC_PORTSC_RESET_CHANGE)
+ xhci_info(xhci, "DbC port reset change\n");
+
+ if (portsc & DBC_PORTSC_LINK_CHANGE)
+ xhci_info(xhci, "DbC port link status change\n");
+
+ if (portsc & DBC_PORTSC_CONFIG_CHANGE)
+ xhci_info(xhci, "DbC config error change\n");
+
+ /* Port reset change bit will be cleared in other place: */
+ writel(portsc & ~DBC_PORTSC_RESET_CHANGE, &dbc->regs->portsc);
+}
+
+static void dbc_handle_tx_event(struct xhci_hcd *xhci, union xhci_trb *event)
+{
+ struct dbc_ep *dep;
+ struct usb_request *req;
+ struct xhci_ring *ring;
+ int ep_id;
+ int status;
+ u32 comp_code;
+ size_t remain_length;
+ struct dbc_request *dreq = NULL, *r;
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ comp_code = GET_COMP_CODE(le32_to_cpu(event->generic.field[2]));
+ remain_length = EVENT_TRB_LEN(le32_to_cpu(event->generic.field[2]));
+ ep_id = TRB_TO_EP_ID(le32_to_cpu(event->generic.field[3]));
+ dep = (ep_id == EPID_OUT) ?
+ dbc->eps[BULK_OUT] : dbc->eps[BULK_IN];
+ ring = dep->ring;
+
+ switch (comp_code) {
+ case COMP_SUCCESS:
+ remain_length = 0;
+ /* FALLTHROUGH */
+ case COMP_SHORT_PACKET:
+ status = 0;
+ break;
+ case COMP_TRB_ERROR:
+ case COMP_BABBLE_DETECTED_ERROR:
+ case COMP_USB_TRANSACTION_ERROR:
+ case COMP_STALL_ERROR:
+ xhci_warn(xhci, "tx error %d detected\n", comp_code);
+ status = -comp_code;
+ break;
+ default:
+ xhci_err(xhci, "unknown tx error %d\n", comp_code);
+ status = -comp_code;
+ break;
+ }
+
+ /* Match the pending request: */
+ list_for_each_entry(r, &dep->pending_list, list) {
+ if (r->trb_dma == event->trans_event.buffer) {
+ dreq = r;
+ break;
+ }
+ }
+
+ if (!dreq) {
+ xhci_warn(xhci, "no matched request\n");
+ return;
+ }
+
+ trace_xhci_dbc_handle_transfer(ring, &dreq->trb->generic);
+
+ req = &dreq->request;
+ ring->num_trbs_free++;
+ req->actual = req->length - remain_length;
+ xhci_dbc_giveback(dreq, status);
+}
+
+static enum evtreturn __xhci_dbc_handle_events(struct xhci_dbc *dbc)
+{
+ dma_addr_t deq;
+ struct dbc_ep *dep;
+ union xhci_trb *evt;
+ u32 ctrl, portsc;
+ struct xhci_hcd *xhci = dbc->xhci;
+ bool update_erdp = false;
+
+ /* DbC state machine: */
+ switch (dbc->state) {
+ case DS_DISABLED:
+ case DS_INITIALIZED:
+
+ return EVT_ERR;
+ case DS_ENABLED:
+ portsc = readl(&dbc->regs->portsc);
+ if (portsc & DBC_PORTSC_CONN_STATUS) {
+ dbc->state = DS_CONNECTED;
+ xhci_info(xhci, "DbC connected\n");
+ }
+
+ return EVT_DONE;
+ case DS_CONNECTED:
+ ctrl = readl(&dbc->regs->control);
+ if (ctrl & DBC_CTRL_DBC_RUN) {
+ dbc->state = DS_CONFIGURED;
+ xhci_info(xhci, "DbC configured\n");
+ portsc = readl(&dbc->regs->portsc);
+ writel(portsc, &dbc->regs->portsc);
+ return EVT_GSER;
+ }
+
+ return EVT_DONE;
+ case DS_CONFIGURED:
+ /* Handle cable unplug event: */
+ portsc = readl(&dbc->regs->portsc);
+ if (!(portsc & DBC_PORTSC_PORT_ENABLED) &&
+ !(portsc & DBC_PORTSC_CONN_STATUS)) {
+ xhci_info(xhci, "DbC cable unplugged\n");
+ dbc->state = DS_ENABLED;
+ xhci_dbc_flush_reqests(dbc);
+
+ return EVT_DISC;
+ }
+
+ /* Handle debug port reset event: */
+ if (portsc & DBC_PORTSC_RESET_CHANGE) {
+ xhci_info(xhci, "DbC port reset\n");
+ writel(portsc, &dbc->regs->portsc);
+ dbc->state = DS_ENABLED;
+ xhci_dbc_flush_reqests(dbc);
+
+ return EVT_DISC;
+ }
+
+ /* Handle endpoint stall event: */
+ ctrl = readl(&dbc->regs->control);
+ if ((ctrl & DBC_CTRL_HALT_IN_TR) ||
+ (ctrl & DBC_CTRL_HALT_OUT_TR)) {
+ xhci_info(xhci, "DbC Endpoint stall\n");
+ dbc->state = DS_STALLED;
+
+ if (ctrl & DBC_CTRL_HALT_IN_TR) {
+ dep = dbc->eps[BULK_IN];
+ xhci_dbc_flush_endpoint_requests(dep);
+ }
+
+ if (ctrl & DBC_CTRL_HALT_OUT_TR) {
+ dep = dbc->eps[BULK_OUT];
+ xhci_dbc_flush_endpoint_requests(dep);
+ }
+
+ return EVT_DONE;
+ }
+
+ /* Clear DbC run change bit: */
+ if (ctrl & DBC_CTRL_DBC_RUN_CHANGE) {
+ writel(ctrl, &dbc->regs->control);
+ ctrl = readl(&dbc->regs->control);
+ }
+
+ break;
+ case DS_STALLED:
+ ctrl = readl(&dbc->regs->control);
+ if (!(ctrl & DBC_CTRL_HALT_IN_TR) &&
+ !(ctrl & DBC_CTRL_HALT_OUT_TR) &&
+ (ctrl & DBC_CTRL_DBC_RUN)) {
+ dbc->state = DS_CONFIGURED;
+ break;
+ }
+
+ return EVT_DONE;
+ default:
+ xhci_err(xhci, "Unknown DbC state %d\n", dbc->state);
+ break;
+ }
+
+ /* Handle the events in the event ring: */
+ evt = dbc->ring_evt->dequeue;
+ while ((le32_to_cpu(evt->event_cmd.flags) & TRB_CYCLE) ==
+ dbc->ring_evt->cycle_state) {
+ /*
+ * Add a barrier between reading the cycle flag and any
+ * reads of the event's flags/data below:
+ */
+ rmb();
+
+ trace_xhci_dbc_handle_event(dbc->ring_evt, &evt->generic);
+
+ switch (le32_to_cpu(evt->event_cmd.flags) & TRB_TYPE_BITMASK) {
+ case TRB_TYPE(TRB_PORT_STATUS):
+ dbc_handle_port_status(xhci, evt);
+ break;
+ case TRB_TYPE(TRB_TRANSFER):
+ dbc_handle_tx_event(xhci, evt);
+ break;
+ default:
+ break;
+ }
+
+ inc_deq(xhci, dbc->ring_evt);
+ evt = dbc->ring_evt->dequeue;
+ update_erdp = true;
+ }
+
+ /* Update event ring dequeue pointer: */
+ if (update_erdp) {
+ deq = xhci_trb_virt_to_dma(dbc->ring_evt->deq_seg,
+ dbc->ring_evt->dequeue);
+ xhci_write_64(xhci, deq, &dbc->regs->erdp);
+ }
+
+ return EVT_DONE;
+}
+
+static void xhci_dbc_handle_events(struct work_struct *work)
+{
+ int ret;
+ enum evtreturn evtr;
+ struct xhci_dbc *dbc;
+ struct xhci_hcd *xhci;
+
+ dbc = container_of(to_delayed_work(work), struct xhci_dbc, event_work);
+ xhci = dbc->xhci;
+
+ spin_lock(&dbc->lock);
+ evtr = __xhci_dbc_handle_events(dbc);
+ spin_unlock(&dbc->lock);
+
+ switch (evtr) {
+ case EVT_GSER:
+ ret = gserial_alloc_line(&dbc->gs_port_num);
+ if (ret) {
+ xhci_err(xhci, "failed to alloc tty line\n");
+ break;
+ }
+
+ ret = gserial_connect(&dbc->gs_port, dbc->gs_port_num);
+ if (ret) {
+ xhci_err(xhci, "failed to register DbC tty\n");
+ gserial_free_line(dbc->gs_port_num);
+ dbc->gs_port_num = GSPORT_INVAL;
+ break;
+ }
+ xhci_info(xhci, "DbC now attached to /dev/ttyGS%d\n",
+ dbc->gs_port_num);
+ mod_delayed_work(system_wq, &dbc->event_work, 1);
+ break;
+ case EVT_DISC:
+ gserial_disconnect(&dbc->gs_port);
+ gserial_free_line(dbc->gs_port_num);
+ dbc->gs_port_num = GSPORT_INVAL;
+
+ mod_delayed_work(system_wq, &dbc->event_work, 1);
+ break;
+ case EVT_DONE:
+ mod_delayed_work(system_wq, &dbc->event_work, 1);
+ break;
+ default:
+ xhci_info(xhci, "stop handling dbc events\n");
+ }
+}
+
+static void xhci_dbc_exit(struct xhci_hcd *xhci)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&xhci->lock, flags);
+ kfree(xhci->dbc);
+ xhci->dbc = NULL;
+ spin_unlock_irqrestore(&xhci->lock, flags);
+}
+
+static int xhci_dbc_init(struct xhci_hcd *xhci)
+{
+ u32 reg;
+ struct xhci_dbc *dbc;
+ unsigned long flags;
+ void __iomem *base;
+ int dbc_cap_offs;
+
+ base = &xhci->cap_regs->hc_capbase;
+ dbc_cap_offs = xhci_find_next_ext_cap(base, 0, XHCI_EXT_CAPS_DEBUG);
+ if (!dbc_cap_offs)
+ return -ENODEV;
+
+ dbc = kzalloc(sizeof(*dbc), GFP_KERNEL);
+ if (!dbc)
+ return -ENOMEM;
+
+ dbc->regs = base + dbc_cap_offs;
+
+ /* We will avoid using DbC in xhci driver if it's in use. */
+ reg = readl(&dbc->regs->control);
+ if (reg & DBC_CTRL_DBC_ENABLE) {
+ kfree(dbc);
+ return -EBUSY;
+ }
+
+ spin_lock_irqsave(&xhci->lock, flags);
+ if (xhci->dbc) {
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ kfree(dbc);
+ return -EBUSY;
+ }
+ xhci->dbc = dbc;
+ spin_unlock_irqrestore(&xhci->lock, flags);
+
+ dbc->xhci = xhci;
+ INIT_DELAYED_WORK(&dbc->event_work, xhci_dbc_handle_events);
+ spin_lock_init(&dbc->lock);
+ dbc->gs_port_num = GSPORT_INVAL;
+
+ return 0;
+}
+
+static ssize_t dbc_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ const char *p;
+ struct xhci_dbc *dbc;
+ struct xhci_hcd *xhci;
+
+ xhci = hcd_to_xhci(dev_get_drvdata(dev));
+ dbc = xhci->dbc;
+
+ switch (dbc->state) {
+ case DS_DISABLED:
+ p = "disabled";
+ break;
+ case DS_INITIALIZED:
+ p = "initialized";
+ break;
+ case DS_ENABLED:
+ p = "enabled";
+ break;
+ case DS_CONNECTED:
+ p = "connected";
+ break;
+ case DS_CONFIGURED:
+ p = "configured";
+ break;
+ case DS_STALLED:
+ p = "stalled";
+ break;
+ default:
+ p = "unknown";
+ }
+
+ return sprintf(buf, "%s\n", p);
+}
+
+static ssize_t dbc_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct xhci_dbc *dbc;
+ struct xhci_hcd *xhci;
+
+ xhci = hcd_to_xhci(dev_get_drvdata(dev));
+ dbc = xhci->dbc;
+
+ if (!strncmp(buf, "enable", 6))
+ xhci_dbc_start(xhci);
+ else if (!strncmp(buf, "disable", 7))
+ xhci_dbc_stop(xhci);
+ else
+ return -EINVAL;
+
+ return count;
+}
+
+static DEVICE_ATTR(dbc, 0644, dbc_show, dbc_store);
+
+int dbc_create_sysfs_file(struct xhci_hcd *xhci)
+{
+ int ret;
+ struct device *dev = xhci_to_hcd(xhci)->self.controller;
+
+ ret = xhci_dbc_init(xhci);
+ if (ret)
+ return ret;
+
+ return device_create_file(dev, &dev_attr_dbc);
+}
+
+void dbc_remove_sysfs_file(struct xhci_hcd *xhci)
+{
+ struct device *dev = xhci_to_hcd(xhci)->self.controller;
+
+ device_remove_file(dev, &dev_attr_dbc);
+ xhci_dbc_stop(xhci);
+ xhci_dbc_exit(xhci);
+}
+
+#ifdef CONFIG_PM
+int xhci_dbc_suspend(struct xhci_hcd *xhci)
+{
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ if (!dbc)
+ return 0;
+
+ if (dbc->state == DS_CONFIGURED)
+ dbc->resume_required = 1;
+
+ xhci_dbc_stop(xhci);
+
+ return 0;
+}
+
+int xhci_dbc_resume(struct xhci_hcd *xhci)
+{
+ int ret = 0;
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ if (!dbc)
+ return 0;
+
+ if (dbc->resume_required) {
+ dbc->resume_required = 0;
+ xhci_dbc_start(xhci);
+ }
+
+ return ret;
+}
+#endif /* CONFIG_PM */
diff --git a/drivers/usb/host/xhci-trace.h b/drivers/usb/host/xhci-trace.h
index 8ce96de..c70d149 100644
--- a/drivers/usb/host/xhci-trace.h
+++ b/drivers/usb/host/xhci-trace.h
@@ -158,6 +158,21 @@ DEFINE_EVENT(xhci_log_trb, xhci_queue_trb,
TP_ARGS(ring, trb)
);
+DEFINE_EVENT(xhci_log_trb, xhci_dbc_handle_event,
+ TP_PROTO(struct xhci_ring *ring, struct xhci_generic_trb *trb),
+ TP_ARGS(ring, trb)
+);
+
+DEFINE_EVENT(xhci_log_trb, xhci_dbc_handle_transfer,
+ TP_PROTO(struct xhci_ring *ring, struct xhci_generic_trb *trb),
+ TP_ARGS(ring, trb)
+);
+
+DEFINE_EVENT(xhci_log_trb, xhci_dbc_gadget_ep_queue,
+ TP_PROTO(struct xhci_ring *ring, struct xhci_generic_trb *trb),
+ TP_ARGS(ring, trb)
+);
+
DECLARE_EVENT_CLASS(xhci_log_virt_dev,
TP_PROTO(struct xhci_virt_device *vdev),
TP_ARGS(vdev),
@@ -453,6 +468,55 @@ DEFINE_EVENT(xhci_log_ring, xhci_inc_deq,
TP_PROTO(struct xhci_ring *ring),
TP_ARGS(ring)
);
+
+DECLARE_EVENT_CLASS(xhci_dbc_log_request,
+ TP_PROTO(struct dbc_request *req),
+ TP_ARGS(req),
+ TP_STRUCT__entry(
+ __dynamic_array(char, name, XHCI_MSG_MAX)
+ __field(struct dbc_request *, req)
+ __field(unsigned int, actual)
+ __field(unsigned int, length)
+ __field(int, status)
+ ),
+ TP_fast_assign(
+ snprintf(__get_str(name), XHCI_MSG_MAX,
+ "%s", req->dep->ep.name);
+ __entry->req = req;
+ __entry->actual = req->request.actual;
+ __entry->length = req->request.length;
+ __entry->status = req->request.status;
+ ),
+ TP_printk("%s: req %p length %u/%u ==> %d",
+ __get_str(name), __entry->req, __entry->actual,
+ __entry->length, __entry->status
+ )
+);
+
+DEFINE_EVENT(xhci_dbc_log_request, xhci_dbc_alloc_request,
+ TP_PROTO(struct dbc_request *req),
+ TP_ARGS(req)
+);
+
+DEFINE_EVENT(xhci_dbc_log_request, xhci_dbc_free_request,
+ TP_PROTO(struct dbc_request *req),
+ TP_ARGS(req)
+);
+
+DEFINE_EVENT(xhci_dbc_log_request, xhci_dbc_queue_request,
+ TP_PROTO(struct dbc_request *req),
+ TP_ARGS(req)
+);
+
+DEFINE_EVENT(xhci_dbc_log_request, xhci_dbc_dequeue_request,
+ TP_PROTO(struct dbc_request *req),
+ TP_ARGS(req)
+);
+
+DEFINE_EVENT(xhci_dbc_log_request, xhci_dbc_giveback_request,
+ TP_PROTO(struct dbc_request *req),
+ TP_ARGS(req)
+);
#endif /* __XHCI_TRACE_H */
/* this part must be outside header guard */
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 56f85df..d01b273 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -627,6 +627,9 @@ int xhci_run(struct usb_hcd *hcd)
}
xhci_dbg_trace(xhci, trace_xhci_dbg_init,
"Finished xhci_run for USB2 roothub");
+
+ dbc_create_sysfs_file(xhci);
+
return 0;
}
EXPORT_SYMBOL_GPL(xhci_run);
@@ -655,6 +658,8 @@ static void xhci_stop(struct usb_hcd *hcd)
return;
}
+ dbc_remove_sysfs_file(xhci);
+
spin_lock_irq(&xhci->lock);
xhci->xhc_state |= XHCI_STATE_HALTED;
xhci->cmd_ring_state = CMD_RING_STATE_STOPPED;
@@ -871,6 +876,8 @@ int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup)
xhci->shared_hcd->state != HC_STATE_SUSPENDED)
return -EINVAL;
+ xhci_dbc_suspend(xhci);
+
/* Clear root port wake on bits if wakeup not allowed. */
if (!do_wakeup)
xhci_disable_port_wake_on_bits(xhci);
@@ -1066,6 +1073,8 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
spin_unlock_irq(&xhci->lock);
+ xhci_dbc_resume(xhci);
+
done:
if (retval == 0) {
/* Resume root hubs only when have pending events. */
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index b4a9b24..ace79ec 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -28,11 +28,13 @@
#include <linux/timer.h>
#include <linux/kernel.h>
#include <linux/usb/hcd.h>
+#include <linux/usb/gadget.h>
#include <linux/io-64-nonatomic-lo-hi.h>
/* Code sharing between pci-quirks and xhci hcd */
-#include "xhci-ext-caps.h"
+#include "xhci-ext-caps.h"
#include "pci-quirks.h"
+#include "../gadget/function/u_serial.h"
/* xHCI PCI Configuration Registers */
#define XHCI_SBRN_OFFSET (0x60)
@@ -1851,6 +1853,8 @@ struct xhci_hcd {
/* platform-specific data -- must come last */
unsigned long priv[0] __aligned(sizeof(s64));
+
+ void *dbc;
};
/* Platform specific overrides to generic XHCI hc_driver ops */
@@ -2111,6 +2115,38 @@ struct xhci_ep_ctx *xhci_get_ep_ctx(struct xhci_hcd *xhci, struct xhci_container
struct xhci_ring *xhci_triad_to_transfer_ring(struct xhci_hcd *xhci,
unsigned int slot_id, unsigned int ep_index,
unsigned int stream_id);
+
+/* xHCI DbC */
+#ifdef CONFIG_USB_XHCI_DBGCAP
+int dbc_create_sysfs_file(struct xhci_hcd *xhci);
+void dbc_remove_sysfs_file(struct xhci_hcd *xhci);
+#ifdef CONFIG_PM
+int xhci_dbc_suspend(struct xhci_hcd *xhci);
+int xhci_dbc_resume(struct xhci_hcd *xhci);
+#endif /* CONFIG_PM */
+#else
+static inline int dbc_create_sysfs_file(struct xhci_hcd *xhci)
+{
+ return 0;
+}
+
+static inline void dbc_remove_sysfs_file(struct xhci_hcd *xhci)
+{
+}
+
+#ifdef CONFIG_PM
+static inline int xhci_dbc_suspend(struct xhci_hcd *xhci)
+{
+ return 0;
+}
+
+static inline int xhci_dbc_resume(struct xhci_hcd *xhci)
+{
+ return 0;
+}
+#endif /* CONFIG_PM */
+#endif /* CONFIG_USB_XHCI_DBGCAP */
+
static inline struct xhci_ring *xhci_urb_to_transfer_ring(struct xhci_hcd *xhci,
struct urb *urb)
{
@@ -2498,4 +2534,155 @@ static inline const char *xhci_decode_ep_context(u32 info, u32 info2, u64 deq,
return str;
}
+/*
+ * xHCI debug capability
+ */
+
+struct dbc_regs {
+ __le32 capability;
+ __le32 doorbell;
+ __le32 ersts; /* Event Ring Segment Table Size*/
+ __le32 __reserved_0; /* 0c~0f reserved bits */
+ __le64 erstba; /* Event Ring Segment Table Base Address */
+ __le64 erdp; /* Event Ring Dequeue Pointer */
+ __le32 control;
+ __le32 status;
+ __le32 portsc; /* Port status and control */
+ __le32 __reserved_1; /* 2b~28 reserved bits */
+ __le64 dccp; /* Debug Capability Context Pointer */
+ __le32 devinfo1; /* Device Descriptor Info Register 1 */
+ __le32 devinfo2; /* Device Descriptor Info Register 2 */
+};
+
+struct dbc_info_context {
+ __le64 string0;
+ __le64 manufacturer;
+ __le64 product;
+ __le64 serial;
+ __le32 length;
+ __le32 __reserved_0[7];
+};
+
+#define DBC_CTRL_DBC_RUN BIT(0)
+#define DBC_CTRL_PORT_ENABLE BIT(1)
+#define DBC_CTRL_HALT_OUT_TR BIT(2)
+#define DBC_CTRL_HALT_IN_TR BIT(3)
+#define DBC_CTRL_DBC_RUN_CHANGE BIT(4)
+#define DBC_CTRL_DBC_ENABLE BIT(31)
+#define DBC_CTRL_MAXBURST(p) (((p) >> 16) & 0xff)
+#define DBC_DOOR_BELL_TARGET(p) (((p) & 0xff) << 8)
+
+#define DBC_MAX_PACKET 1024
+#define DBC_MAX_STRING_LENGTH 64
+#define DBC_STRING_MANUFACTURER "Linux"
+#define DBC_STRING_PRODUCT "Remote GDB"
+#define DBC_STRING_SERIAL "0001"
+#define DBC_CONTEXT_SIZE 64
+
+/*
+ * Port status:
+ */
+#define DBC_PORTSC_CONN_STATUS BIT(0)
+#define DBC_PORTSC_PORT_ENABLED BIT(1)
+#define DBC_PORTSC_CONN_CHANGE BIT(17)
+#define DBC_PORTSC_RESET_CHANGE BIT(21)
+#define DBC_PORTSC_LINK_CHANGE BIT(22)
+#define DBC_PORTSC_CONFIG_CHANGE BIT(23)
+
+struct dbc_strings {
+ char string0[DBC_MAX_STRING_LENGTH];
+ char manufacturer[DBC_MAX_STRING_LENGTH];
+ char product[DBC_MAX_STRING_LENGTH];
+ char serial[DBC_MAX_STRING_LENGTH];
+};
+
+#define DBC_PROTOCOL 1 /* GNU Remote Debug Command */
+#define DBC_VENDOR_ID 0x1d6b /* Linux Foundation 0x1d6b */
+#define DBC_PRODUCT_ID 0x0004 /* device 0004 */
+#define DBC_DEVICE_REV 0x0010 /* 0.10 */
+
+enum dbc_state {
+ DS_DISABLED = 0,
+ DS_INITIALIZED,
+ DS_ENABLED,
+ DS_CONNECTED,
+ DS_CONFIGURED,
+ DS_STALLED,
+};
+
+struct dbc_ep {
+ struct usb_ep ep;
+ struct xhci_dbc *dbc;
+ struct list_head pending_list;
+ struct xhci_ring *ring;
+
+ unsigned direction:1;
+};
+
+struct dbc_request {
+ struct usb_request request;
+ struct dbc_ep *dep;
+ struct list_head list;
+ dma_addr_t trb_dma;
+ union xhci_trb *trb;
+
+ unsigned direction:1;
+};
+
+#define ep_to_dep(e) (container_of(e, struct dbc_ep, ep))
+#define req_to_dreq(r) (container_of(r, struct dbc_request, request))
+
+/*
+ * Private structure for DbC hardware state:
+ */
+struct xhci_dbc {
+ struct xhci_hcd *xhci;
+ struct dbc_regs __iomem *regs;
+ struct xhci_ring *ring_evt;
+ struct xhci_ring *ring_in;
+ struct xhci_ring *ring_out;
+ struct xhci_erst erst;
+ struct xhci_container_ctx *ctx;
+
+ struct dbc_strings *string;
+ dma_addr_t string_dma;
+ size_t string_size;
+
+ enum dbc_state state;
+ struct delayed_work event_work;
+ unsigned resume_required:1;
+
+ unsigned char gs_port_num;
+ struct gserial gs_port;
+ struct dbc_ep *eps[2];
+
+ /* device lock */
+ spinlock_t lock;
+};
+
+#define dbc_bulkout_ctx(d) \
+ ((struct xhci_ep_ctx *)((d)->ctx->bytes + DBC_CONTEXT_SIZE))
+#define dbc_bulkin_ctx(d) \
+ ((struct xhci_ep_ctx *)((d)->ctx->bytes + DBC_CONTEXT_SIZE * 2))
+#define dbc_bulkout_enq(d) \
+ xhci_trb_virt_to_dma((d)->ring_out->enq_seg, (d)->ring_out->enqueue)
+#define dbc_bulkin_enq(d) \
+ xhci_trb_virt_to_dma((d)->ring_in->enq_seg, (d)->ring_in->enqueue)
+#define dbc_epctx_info2(t, p, b) \
+ cpu_to_le32(EP_TYPE(t) | MAX_PACKET(p) | MAX_BURST(b))
+#define dbc_ep_dma_direction(d) \
+ ((d)->direction ? DMA_FROM_DEVICE : DMA_TO_DEVICE)
+
+#define GSPORT_INVAL ((unsigned char)(-1))
+#define BULK_OUT 0
+#define BULK_IN 1
+#define EPID_OUT 2
+#define EPID_IN 3
+
+enum evtreturn {
+ EVT_ERR = -1,
+ EVT_DONE,
+ EVT_GSER,
+ EVT_DISC,
+};
#endif /* __LINUX_XHCI_HCD_H */
--
2.7.4
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 3/3] usb: doc: Update document for USB3 debug port usage
2017-07-21 8:52 [PATCH 0/3] usb: xhci: Add debug capability support in xhci Lu Baolu
2017-07-21 8:52 ` [PATCH 1/3] usb: xhci: Make some static functions global Lu Baolu
2017-07-21 8:52 ` [PATCH 2/3] usb: xhci: Add DbC support in xHCI driver Lu Baolu
@ 2017-07-21 8:52 ` Lu Baolu
2 siblings, 0 replies; 6+ messages in thread
From: Lu Baolu @ 2017-07-21 8:52 UTC (permalink / raw)
To: Mathias Nyman, Greg Kroah-Hartman; +Cc: linux-usb, linux-kernel, Lu Baolu
Update Documentation/driver-api/usb/usb3-debug-port.rst. This update
includes the guide for using xHCI debug capability based TTY serial
link.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
Documentation/driver-api/usb/usb3-debug-port.rst | 68 ++++++++++++++++++++++++
1 file changed, 68 insertions(+)
diff --git a/Documentation/driver-api/usb/usb3-debug-port.rst b/Documentation/driver-api/usb/usb3-debug-port.rst
index feb1a36..e4bb02e 100644
--- a/Documentation/driver-api/usb/usb3-debug-port.rst
+++ b/Documentation/driver-api/usb/usb3-debug-port.rst
@@ -98,3 +98,71 @@ you to check the sanity of the setup.
cat /dev/ttyUSB0
done
===== end of bash scripts ===============
+
+Serial TTY
+==========
+
+DbC has also been designed for a serial TTY device at runtime.
+One use of this is running a login service on the debug target.
+Hence it can be remote accessed by the debug host. Another use
+can probably be found in servers. It provides a peer-to-peer USB
+link between two host-only machines. This provides a reasonable
+out-of-band communication method between two servers.
+
+In order to use this, you need to make sure your kernel has been
+configured to support USB_XHCI_DBGCAP. A sysfs attribute under
+the xHCI device node is used to enable or disable DbC. By default,
+DbC is disabled::
+
+ root@target:/sys/bus/pci/devices/0000:00:14.0# cat dbc
+ disabled
+
+Enable DbC with the following command::
+
+ root@target:/sys/bus/pci/devices/0000:00:14.0# echo enable > dbc
+
+You can check the DbC state at anytime::
+
+ root@target:/sys/bus/pci/devices/0000:00:14.0# cat dbc
+ enabled
+
+Connect the debug target to the debug host with a USB 3.0 super-
+speed A-to-A debugging cable. You can see the /dev/ttyGSn created
+on the debug target. You will see below kernel message lines::
+
+ root@target: tail -f /var/log/kern.log
+ [ 182.730103] xhci_hcd 0000:00:14.0: DbC connected
+ [ 191.169420] xhci_hcd 0000:00:14.0: DbC configured
+ [ 191.169597] xhci_hcd 0000:00:14.0: DbC now attached to /dev/ttyGS0
+
+Accordingly, the DbC state has been brought up to::
+
+ root@host:/sys/bus/pci/devices/0000:00:14.0# cat dbc
+ configured
+
+On the debug host, you will see the debug device has been enumerated.
+You will see below kernel message lines::
+
+ root@host: tail -f /var/log/kern.log
+ [ 79.454780] usb 2-2.1: new SuperSpeed USB device number 3 using xhci_hcd
+ [ 79.475003] usb 2-2.1: LPM exit latency is zeroed, disabling LPM.
+ [ 79.475389] usb 2-2.1: New USB device found, idVendor=1d6b, idProduct=0004
+ [ 79.475390] usb 2-2.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
+ [ 79.475391] usb 2-2.1: Product: Remote GDB
+ [ 79.475392] usb 2-2.1: Manufacturer: Linux
+ [ 79.475393] usb 2-2.1: SerialNumber: 0001
+ [ 79.660368] usb_debug 2-2.1:1.0: xhci_dbc converter detected
+ [ 79.660439] usb 2-2.1: xhci_dbc converter now attached to ttyUSB0
+
+You can simply verify whether it works by::
+
+ # On target side
+ root@target: echo "Hello world" > /dev/ttyGS0
+
+ # On host side
+ root@host: cat /dev/ttyUSB0
+ Hello world
+
+ # vice versa
+
+You have a workable serial link over USB now.
--
2.7.4
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 2/3] usb: xhci: Add DbC support in xHCI driver
2017-07-21 8:52 ` [PATCH 2/3] usb: xhci: Add DbC support in xHCI driver Lu Baolu
@ 2017-07-21 10:31 ` Felipe Balbi
2017-07-24 3:59 ` Lu Baolu
0 siblings, 1 reply; 6+ messages in thread
From: Felipe Balbi @ 2017-07-21 10:31 UTC (permalink / raw)
To: Lu Baolu, Mathias Nyman, Greg Kroah-Hartman
Cc: linux-usb, linux-kernel, Lu Baolu
[-- Attachment #1: Type: text/plain, Size: 564 bytes --]
Hi,
Lu Baolu <baolu.lu@linux.intel.com> writes:
> +static void xhci_dbc_stop(struct xhci_hcd *xhci)
> +{
> + struct xhci_dbc *dbc = xhci->dbc;
> +
> + WARN_ON(!dbc);
> +
> + cancel_delayed_work_sync(&dbc->event_work);
> +
> + if (dbc->gs_port_num != GSPORT_INVAL) {
> + gserial_disconnect(&dbc->gs_port);
> + gserial_free_line(dbc->gs_port_num);
why are you tying host stack to the gadget framework?
With this, you're forcing every single PC in the world to compile the
gadget framework, that's a bit much don't you think?
--
balbi
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 832 bytes --]
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 2/3] usb: xhci: Add DbC support in xHCI driver
2017-07-21 10:31 ` Felipe Balbi
@ 2017-07-24 3:59 ` Lu Baolu
0 siblings, 0 replies; 6+ messages in thread
From: Lu Baolu @ 2017-07-24 3:59 UTC (permalink / raw)
To: Felipe Balbi, Mathias Nyman, Greg Kroah-Hartman; +Cc: linux-usb, linux-kernel
Hi Felipe,
On 07/21/2017 06:31 PM, Felipe Balbi wrote:
> Hi,
>
> Lu Baolu <baolu.lu@linux.intel.com> writes:
>> +static void xhci_dbc_stop(struct xhci_hcd *xhci)
>> +{
>> + struct xhci_dbc *dbc = xhci->dbc;
>> +
>> + WARN_ON(!dbc);
>> +
>> + cancel_delayed_work_sync(&dbc->event_work);
>> +
>> + if (dbc->gs_port_num != GSPORT_INVAL) {
>> + gserial_disconnect(&dbc->gs_port);
>> + gserial_free_line(dbc->gs_port_num);
> why are you tying host stack to the gadget framework?
XHCI debug capability is actually a debug device gadget.
The hardware and firmware do everything of gadget work
and leave the interface to xHCI for enabling/disabling and
queuing transfer requests.
u_serial.c provides a generic layer between a USB gadget
and the TTY layer. I used it to avoid duplicating code.
>
> With this, you're forcing every single PC in the world to compile the
> gadget framework, that's a bit much don't you think?
>
Yes, you are right. Is it acceptable if I move u_serial.c from
the current place to drivers/usb/common?
Best regards,
Lu Baolu
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2017-07-24 3:59 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-07-21 8:52 [PATCH 0/3] usb: xhci: Add debug capability support in xhci Lu Baolu
2017-07-21 8:52 ` [PATCH 1/3] usb: xhci: Make some static functions global Lu Baolu
2017-07-21 8:52 ` [PATCH 2/3] usb: xhci: Add DbC support in xHCI driver Lu Baolu
2017-07-21 10:31 ` Felipe Balbi
2017-07-24 3:59 ` Lu Baolu
2017-07-21 8:52 ` [PATCH 3/3] usb: doc: Update document for USB3 debug port usage Lu Baolu
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