Versatile Express platform can be used in different configurations,
the console UART used by early printk may be located at different
addresses in the address space.

This patch makes it possible to select the base address of a PL011
UART to be used as a console output in the kernel configuration.
The default behaviour is still the heuristic detecting memory map
on Cortex-A core tiles.

The zImage decompressor will use the same configuration values
or print out nothing if DEBUG_LL is not enabled.
Signed-off-by: NPawel Moll <pawel.moll@arm.com>

This patch introduces a new Kconfig option which, when enabled, causes
the kernel to write the PID of the current task into the PROCID field
of the CONTEXTIDR on context switch. This is useful when analysing
hardware trace, since writes to this register can be configured to emit
an event into the trace stream.

The thread notifier for writing the PID is deliberately kept separate
from the ASID-writing code so that we can support newer processors using
LPAE, where the ASID is stored in TTBR0. As such, the switch_mm code is
updated to perform a read-modify-write sequence to ensure that we don't
clobber the PID on CPUs using the classic 2-level page tables.
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

To be able to enable early debugging on boards using the UART2 for the
console, add the option for early debugging on UART2.
Signed-off-by: NDirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>

Apart from the necessity to do this change for multi-platform kernels
the previous logic depended on the zImage decompressor to write the
physical and virtual address to a magic memory location.
If the decompressor is unused or not correctly configured for the
current machid, the addruart macro was an infinite loop. Moreover
debugging the early zImage code was not possible either.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
[nsekhar@ti.com: add braces in _DEBUG_LL_ENTRY() macro to fix checkpatch
error. Fix debug port choice config dependency for traditional DaVincis.
Modify debug port config names and add help text.]
Signed-off-by: NSekhar Nori <nsekhar@ti.com>

This is a very simple method for code running in an emulator, or under
the supervision of a debugger, to use I/O facilities on the controlling
host.

Tested with OpenOCD, and ARM's Fast Models.

Details on semihosting can be found in chapter 8 of
DUI0203I_rvct_developer_guide.pdf from ARM Ltd.
Signed-off-by: NNicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Different boards may use differenct UART ports for debugging.
To be able to add different debug UART configurations (e.g. UART2),
rename the existing general DEBUG_IMX6Q_UART to DEBUG_IMX6Q_UART4.
Signed-off-by: NDirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>

Following removal announce and addition to feature-removal-schedule.txt,
here is the actual source code deletion for Atmel CAP9 family.
Signed-off-by: NJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>

Arrange the Kconfig options in rough alphabetical order, and place the
default 'none' and 'icedcc' options at the end.  This prefers the
platform specific debug option rather than the 'none' option, which is
what we actually want.
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

we will select now the DBGU used by the soc at Kconfig level

For the DEBUG_LL and early_printk this will allow to select which DBGU to use
this will also allow to select them when multiple SOC are enabled
Signed-off-by: NJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>

Add support for DEBUG_LL on the 8660 and 8960 development boards.
While we're here cleanup the uncompress.h code a bit. Avoid
the use of readl/writel as those are Linux specific APIs that
aren't guaranteed to work in the decompressor.

Cc: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Acked-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NDavid Brown <davidb@codeaurora.org>

Now that DEBUG_LL is a choice we can move MSM's homegrown choice
menu to DEBUG_LL.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NDavid Brown <davidb@codeaurora.org>

It adds the core definitions and low-level debug uart support
for imx6q.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>

This adds basic support for the Calxeda Highbank platform.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Reviewed-by: NJamie Iles <jamie@jamieiles.com>
Reviewed-by: NShawn Guo <shawn.guo@linaro.org>

Now that the DEBUG_LL UART can be selected by a Kconfig choice,
simplify the #ifdefery in debug-macro.S and add entries to the
top-level Kconfig.debug instead.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Now that the DEBUG_LL UART can be selected by a Kconfig choice, simplify
the #ifdefery in debug-macro.S and add entries to the top-level
Kconfig.debug instead.
Acked-by: NNicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Now that the DEBUG_LL UART can be selected by a Kconfig choice, convert
the Samsung UART selection to use a set of bools rather than an int.
Acked-by: NNicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Defaulting to DEBUG_ICEDCC will cause systems to hang during boot unless
a hardware debugger is listening to the debug comms. channel.

This patch adds a dummy UART option as the default DEBUG_LL choice which
requires the platform to do the right thing.
Acked-by: NStephen Boyd <sboyd@codeaurora.org>
Tested-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

DEBUG_ICEDCC support is just another DEBUG_LL choice and
selecting it along with other DEBUG_LL options doesn't make
much sense. Put it into the DEBUG_LL choice to avoid confusion.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

ARM patch 7072/1 (debug: use kconfig choice for selecting
DEBUG_LL UART) didn't notice that the Kconfigs relied on being
unselected to configure a different serial port. Since there is
no NONE option in a choice menu, explicitly add the other option
so that both serial ports can be selected.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Enabled DEBUG_LL hardcodes the UART address into the kernel and results
in a non-portable kernel image. Since this option is only intended for
use when debugging early boot failures, supporting multiple platforms
in such a configuration is not the intended use-case.

This patch documents this limitation in the DEBUG_LL Kconfig help text,
so that users are aware of the portability restrictions that are associated
with enabling low-level debugging support.
Reported-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Enabling CONFIG_DEBUG_LL (which is required for earlyprintk) hardwires
the debug UART address into the kernel, so that we can print before the
platform is initialised.

If the user inadvertently selects multiple platforms with DEBUG_LL
enabled, the UART address may not be correct and will likely cause the
kernel to hang in the very early stages of boot.

This patch, based on a skeleton from Russell, uses a Kconfig choice for
selecting the DEBUG_LL UART, therefore allowing the user to make a
choice about the supported platform when DEBUG_LL is enabled.
Acked-by: NNicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The CONFIG_ARM_AMBA symbol is selected by the platforms that support
AMBA, and the other platforms (e.g. orion) might not be able to
build that code at all when they do not support the clk API.

Instead, make sure that OC_ETM is only built on platforms that
do support the amba subsystem already.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

Signed-off-by: NJon Medhurst <tixy@yxit.co.uk>
Acked-by: NNicolas Pitre <nicolas.pitre@linaro.org>

Most arches define CONFIG_DEBUG_STACK_USAGE exactly the same way.  Move it
to lib/Kconfig.debug so each arch doesn't have to define it.  This
obviously makes the option generic, but that's fine because the config is
already used in generic code.

It's not obvious to me that sysrq-P actually does anything caution by
keeping the most inclusive wording.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NRichard Weinberger <richard@nod.at>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Acked-by: NRalf Baechle <ralf@linux-mips.org>
Cc: Paul Mackerras <paulus@samba.org>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This config option isn't actually used anywhere and can be safely
removed. The last user was traps.c before commit 082f47a7 ([ARM]
always allow dump_stack() to produce a backtrace, 2007-07-05).
Reviewed-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

It is kernel-wide policy that options depending on EXPERIMENTAL should
also have '(EXPERIMENTAL)' in their option text, and options with
'(EXPERIMENTAL)' depend on EXPERIMENTAL.

Ensure that all ARM options comply with this.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add the options to enable the function graph tracer on ARM.  Function
graph tracer support requires frame pointers, so exclude Thumb-2 and
also make sure FRAME_POINTER gets enabled when FUNCTION_GRAPH_TRACER is
used, since FUNCTION_TRACER doesn't "select FRAME_POINTER" when
ARM_UNWIND is used.  Therefore, with GCC 4.4.0+, you get plain function
tracing without frame pointers, but you'll need them if you want
function graph tracing.
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NRabin Vincent <rabin@rab.in>

There are very few legitimate use cases, if any, for directly accessing
system RAM through /dev/mem.  So let's mimic what they do on x86 and
forbid it when CONFIG_STRICT_DEVMEM is turned on.
Signed-off-by: NNicolas Pitre <nicolas.pitre@linaro.org>

With a new enough GCC, ARM function tracing can be supported without the
need for frame pointers.  This is essential for Thumb-2 support, since
frame pointers aren't available then.
Acked-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NRabin Vincent <rabin@rab.in>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Move the Kconfig entries from plat-s3c to plat-samsung and plat-s3c24xx
as necessary. The S3C_BOOT entries and the DMA configuration can go to
plat-samsung. The low-level UART configurations are currently S3C2XX
specific and can go to plat-s3c24xx.

Eliminating plat-s3c from the build process will be submitted seperately.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

This patch allows an earlyprintk console if CONFIG_DEBUG_LL is enabled,
using the printch asm function.

The patch is based on the original work by Sascha Hauer.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: NPavel Machek <pavel@ucw.cz>

This driver implements support for on-chip Embedded Tracing Macrocell and
Embedded Trace Buffer. It allows to trigger tracing of kernel execution flow
and exporting trace output to userspace via character device and a sysrq
combo.

Trace output can then be decoded by a fairly simple open source tool [1]
which is already sufficient to get the idea of what the kernel is doing.

[1]: http://github.com/virtuoso/etm2humanSigned-off-by: NAlexander Shishkin <virtuoso@slind.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch adds the necessary entries to the Makefile and Kconfig
files for building the Thumb-2 kernel.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Remove the unused CONFIG_DEBUG_S3C_PORT as we currently only have
support for using the S3C UARTs via the low-level debug code.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

SCALE: add ice dcc support

Tested on the ixp425 with the ice PEEDI
Ack-by: NEric Miao <eric.miao@marvell.com>
Signed-off-by: NJean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch also makes the frame pointer default to y only if
!ARM_UNWIND. LOCKDEP no longer selects FRAME_POINTER if ARM_UNWIND is
enabled.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

In early 2.6 days stack utilization instrumentation was made
configurable. Seems that arm misses the DEBUG_STACK_USAGE option.
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Rename DEBUG_S3C2410_PORT to DEBUG_S3C_PORT as well as
DEBUG_S3C2410_UART to DEBUG_S3C_UART as part of the updates
to moving to plat-s3c for S3C base support.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Rename CONFIG_S3C2410_LOWLEVEL_UART_PORT to be
CONFIG_S3C_LOWLEVEL_UART_PORT as we move to using
plat-s3c for base of S3C operations.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

DEBUG_WAITQ appears to have been removed by others, but no one
removed the configuration option from ARM.  Remote it from both
Kconfig.debug and all default configurations.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>