linux_dsm_epyc7002/include/linux/usb
Lu Baolu aeb9dd1de9 usb/early: Add driver for xhci debug capability
XHCI debug capability (DbC) is an optional but standalone
functionality provided by an xHCI host controller. Software
learns this capability by walking through the extended
capability list of the host. XHCI specification describes
DbC in section 7.6.

This patch introduces the code to probe and initialize the
debug capability hardware during early boot. With hardware
initialized, the debug target (system on which this code is
running) will present a debug device through the debug port
(normally the first USB3 port). The debug device is fully
compliant with the USB framework and provides the equivalent
of a very high performance (USB3) full-duplex serial link
between the debug host and target. The DbC functionality is
independent of the xHCI host. There isn't any precondition
from the xHCI host side for the DbC to work.

One use for this feature is kernel debugging, for example
when your machine crashes very early before the regular
console code is initialized. Other uses include simpler,
lockless logging instead of a full-blown printk console
driver and klogd.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathias Nyman <mathias.nyman@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-usb@vger.kernel.org
Link: http://lkml.kernel.org/r/1490083293-3792-3-git-send-email-baolu.lu@linux.intel.com
[ Small fix to the Kconfig help text. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-21 12:30:05 +01:00
..
association.h
atmel_usba_udc.h
audio-v2.h
audio.h
c67x00.h
cdc_ncm.h NET: usb: cdc_mbim: add quirk for supporting Telit LE922A 2016-12-08 13:02:25 -05:00
cdc-wdm.h
cdc.h
ch9.h
chipidea.h usb: chipidea: msm: Handle phy power states 2017-01-20 15:27:35 +08:00
composite.h
ehci_def.h
ehci_pdriver.h
ehci-dbgp.h
ezusb.h
functionfs.h
g_hid.h
gadget_configfs.h
gadget.h
gpio_vbus.h
hcd.h usb: hcd.h: construct hub class request constants from simpler constants 2016-12-05 16:37:10 +01:00
input.h
iowarrior.h
irda.h
isp116x.h
isp1301.h
isp1362.h
isp1760.h
m66592.h
msm_hsusb_hw.h
musb-ux500.h
musb.h
net2280.h
of.h
ohci_pdriver.h
otg-fsm.h
otg.h
phy_companion.h
phy.h
quirks.h
r8a66597.h
renesas_usbhs.h
rndis_host.h
samsung_usb_phy.h
serial.h
sl811.h
storage.h
tegra_usb_phy.h
tilegx.h
uas.h
ulpi.h
usb338x.h
usb_phy_generic.h
usbnet.h
wusb-wa.h
wusb.h
xhci-dbgp.h usb/early: Add driver for xhci debug capability 2017-03-21 12:30:05 +01:00