[ Upstream commit 2b7eec2ec3015f52fc74cf45d0408925e984ecd1 ]

Using the kernel param earlyprintk=xdbc,keep without proper hardware
setup leads to this:

	[ ] xhci_dbc:early_xdbc_parse_parameter: dbgp_num: 0
	...
	[ ] xhci_dbc:early_xdbc_setup_hardware: failed to setup the connection to host
	...
	[ ] calling  kmemleak_late_init+0x0/0xa0 @ 1
	[ ] kmemleak: Kernel memory leak detector initialized (mem pool available: 14919)
	[ ] kmemleak: Automatic memory scanning thread started
	[ ] initcall kmemleak_late_init+0x0/0xa0 returned 0 after 417 usecs
	[ ] calling  check_early_ioremap_leak+0x0/0x70 @ 1
	[ ] ------------[ cut here ]------------
	[ ] Debug warning: early ioremap leak of 1 areas detected.
	    please boot with early_ioremap_debug and report the dmesg.
	[ ] WARNING: CPU: 11 PID: 1 at mm/early_ioremap.c:90 check_early_ioremap_leak+0x4e/0x70

When early_xdbc_setup_hardware() fails, make sure to call
early_iounmap() since xdbc_init() won't handle it.

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Fixes: aeb9dd1de98c ("usb/early: Add driver for xhci debug capability")
Link: https://lore.kernel.org/r/20250627-xdbc-v1-1-43cc8c317b1b@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit a4a97ab3db5c081eb6e7dba91306adefb461e0bd ]

If xdbc_bulk_write() fails, the values in 'buf' can be anything. So the
string is not guaranteed to be NULL terminated when xdbc_trace() is called.

Reserve an extra byte, which will be zeroed automatically because 'buf' is
a static variable, in order to avoid troubles, should it happen.

Fixes: aeb9dd1de98c ("usb/early: Add driver for xhci debug capability")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/d6a7562c5e839a195cee85db6dc81817f9372cb1.1675016180.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit c4d936efa46d8ea183df16c0f3fa4423327da51d ]

This reverts commit 796eed4b2342c9d6b26c958e92af91253a2390e1.

This change causes boot lockups when using "arlyprintk=xdbc" because
ktime can not be used at this point in time in the boot process.  Also,
it is not needed for very small delays like this.

Reported-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Cc: Jann Horn <jannh@google.com>
Cc: Chunfeng Yun <chunfeng.yun@mediatek.com>
Fixes: 796eed4b2342 ("usb: early: convert to readl_poll_timeout_atomic()")
Link: https://lore.kernel.org/r/c2b5c9bb-1b75-bf56-3754-b5b18812d65e@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Use readl_poll_timeout_atomic() to simplify code

Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Petr Mladek <pmladek@suse.com>
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1600668815-12135-2-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Use readl_poll_timeout_atomic() to simplify code

Cc: Lu Baolu <baolu.lu@linux.intel.com>
Cc: Mathias Nyman <mathias.nyman@linux.intel.com>
Reviewed-by: Jann Horn <jannh@google.com>
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1600668815-12135-1-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Demote xhci-dbc's file header to a standard comment block.

Fixes the following W=1 kernel build warning(s):

 drivers/usb/early/xhci-dbc.c:10: warning: Function parameter or member 'fmt' not described in 'pr_fmt'

Cc: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20200706133341.476881-28-lee.jones@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

If the header file containing a function's prototype isn't included by
the sourcefile containing the associated function, the build system
complains of missing prototypes.

Fixes the following W=1 kernel build warning(s):

 drivers/usb/early/ehci-dbgp.c: In function ‘early_dbgp_write’:
 drivers/usb/early/ehci-dbgp.c:915:13: warning: variable ‘ret’ set but not used [-Wunused-but-set-variable]
 915 | int chunk, ret;
 | ^~~
 drivers/usb/early/xhci-dbc.c:600:12: warning: no previous prototype for ‘early_xdbc_parse_parameter’ [-Wmissing-prototypes]
 600 | int __init early_xdbc_parse_parameter(char *s)
 | ^~~~~~~~~~~~~~~~~~~~~~~~~~
 drivers/usb/early/xhci-dbc.c:653:12: warning: no previous prototype for ‘early_xdbc_setup_hardware’ [-Wmissing-prototypes]
 653 | int __init early_xdbc_setup_hardware(void)
 | ^~~~~~~~~~~~~~~~~~~~~~~~~
 drivers/usb/early/xhci-dbc.c:910:13: warning: no previous prototype for ‘early_xdbc_register_console’ [-Wmissing-prototypes]
 910 | void __init early_xdbc_register_console(void)
 | ^~~~~~~~~~~~~~~~~~~~~~~~~~~

Cc: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/r/20200706133341.476881-27-lee.jones@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

'ret' hasn't  been checked since the driver's inception in 2009.

Fixes the following W=1 kernel build warning(s):

 drivers/usb/early/ehci-dbgp.c: In function ‘early_dbgp_write’:
 drivers/usb/early/ehci-dbgp.c:915:13: warning: variable ‘ret’ set but not used [-Wunused-but-set-variable]
 915 | int chunk, ret;
 | ^~~

Cc: Sumit Garg <sumit.garg@linaro.org>
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Link: https://lore.kernel.org/r/20200706133341.476881-26-lee.jones@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In kgdb context, calling console handlers aren't safe due to locks used
in those handlers which could in turn lead to a deadlock. Although, using
oops_in_progress increases the chance to bypass locks in most console
handlers but it might not be sufficient enough in case a console uses
more locks (VT/TTY is good example).

Currently when a driver provides both polling I/O and a console then kdb
will output using the console. We can increase robustness by using the
currently active polling I/O driver (which should be lockless) instead
of the corresponding console. For several common cases (e.g. an
embedded system with a single serial port that is used both for console
output and debugger I/O) this will result in no console handler being
used.

In order to achieve this we need to reverse the order of preference to
use dbg_io_ops (uses polling I/O mode) over console APIs. So we just
store "struct console" that represents debugger I/O in dbg_io_ops and
while emitting kdb messages, skip console that matches dbg_io_ops
console in order to avoid duplicate messages. After this change,
"is_console" param becomes redundant and hence removed.

Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/1591264879-25920-5-git-send-email-sumit.garg@linaro.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>

We need the USB fixes in here too.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>