ARM: 9043/1: tegra: Fix misplaced tegra_uart_config in decompressor

The tegra_uart_config of the DEBUG_LL code is now placed right at the
start of the .text section after commit which enabled debug

ARM: 9043/1: tegra: Fix misplaced tegra_uart_config in decompressor

The tegra_uart_config of the DEBUG_LL code is now placed right at the
start of the .text section after commit which enabled debug output in the
decompressor. Tegra devices are not booting anymore if DEBUG_LL is enabled
since tegra_uart_config data is executes as a code. Fix the misplaced
tegra_uart_config storage by embedding it into the code.

Cc: stable@vger.kernel.org
Fixes: 2596a72d3384 ("ARM: 9009/1: uncompress: Enable debug in head.S")
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

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ARM: 9005/1: debug: Select flow control for all debug UARTs

Instead of a flow control selection mechanism specifically for
8250, make this available for all debug UARTs. If the debug
UART supports w

ARM: 9005/1: debug: Select flow control for all debug UARTs

Instead of a flow control selection mechanism specifically for
8250, make this available for all debug UARTs. If the debug
UART supports waiting for CTS to be asserted, then this code
can be activated for terminals that need it.

We keep the defaults for EBSA110, Footbridge, Gemini and RPC
so that this still works as expected for these older platforms:
they assume that flow control shall be enabled for debug
prints.

I switch the location of the check for
ifdef CONFIG_DEBUG_UART_FLOW_CONTROL from the actual debug
UART drivers: the code would get compiled-out for 8250 and
Tegra unless their custom config (or passing -DFLOW_CONTROL
in the Tegra case) was not set. Instead this is conditional
at the three places where we print debug messages. The idea
is that debug UARTs can be implemented without this ifdef
boilerplate so they look cleaner, alas the ifdef has to be
somewhere.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

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ARM: 9004/1: debug: Split waituart to CTS and TXRDY

This patch was triggered by a remark from Russell that
introducing a call to the waituart (needed to fix debug prints
on the Qualcomm platforms) w

ARM: 9004/1: debug: Split waituart to CTS and TXRDY

This patch was triggered by a remark from Russell that
introducing a call to the waituart (needed to fix debug prints
on the Qualcomm platforms) was dangerous because in some cases
this will involve waiting for a modem CTS (clear to send)
signal, and debug messages would maybe not work on platforms
with no modem connected to the UART port: they will just
hang waiting for the modem to assert CTS and this might never
happen.

Looking through all UART debug drivers implementing the waituart
macro I discovered that all users except two actually use this
macro to check if the UART is ready for TX, let's call this
TXRDY.

Only two debug UART drivers actually check for CTS:
- arch/arm/include/debug/8250.S
- arch/arm/include/debug/tegra.S

The former is very significant since the 8250 is possibly
the most common UART on the planet.

We have the following problem: the semantics of waituart are
ambiguous making it dangerous to introduce the macro to debug
code fixing debug prints for Qualcomm. To start to pry this
problem apart, this patch does the following:

- Convert all debug UART drivers to define two macros:

- waituartcts with the clear semantic to wait for CTS
to be asserted

- waituarttxrdy with the clear semantic to wait for the TX
capability of the UART to be ready

- When doing this take care to assign the right function to
each drivers macro, so they now do exactly the above.

- Update the three sites in the kernel invoking the waituart
macro to call waituartcts/waituarttxrdy in sequence, so that
the functional impact on the kernel should be zero.

After this we can start to change the code sites using this
code to do the right thing.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282

Based on 1 normalized pattern(s):

this software is licensed under the terms of the gnu general public
license version 2 as pub

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282

Based on 1 normalized pattern(s):

this software is licensed under the terms of the gnu general public
license version 2 as published by the free software foundation and
may be copied distributed and modified under those terms this
program is distributed in the hope that it will be useful but
without any warranty without even the implied warranty of
merchantability or fitness for a particular purpose see the gnu
general public license for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 285 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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ARM: 8844/1: use unified assembler in assembly files

Use unified assembler syntax (UAL) in assembly files. Divided
syntax is considered deprecated. This will also allow to build
the kernel using LLV

ARM: 8844/1: use unified assembler in assembly files

Use unified assembler syntax (UAL) in assembly files. Divided
syntax is considered deprecated. This will also allow to build
the kernel using LLVM's integrated assembler.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

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ARM: tegra: make debug_ll code build for ARMv6

In a combined ARMv6/v7 kernel, we cannot use the
movt/movw instructions to load an immediate, as they
are not valid on ARMv6.

This changes the file to

ARM: tegra: make debug_ll code build for ARMv6

In a combined ARMv6/v7 kernel, we cannot use the
movt/movw instructions to load an immediate, as they
are not valid on ARMv6.

This changes the file to use an indirect load instead,
as lots of other implementations do.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: linux-tegra@vger.kernel.org

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ARM: tegra: don't hard-code DEBUG_LL baud rate

Stop writing to the UART clock divider registers in the Tegra DEBUG_LL
code. This allows the DEBUG_LL output to use whatever baud rate was set
up by th

ARM: tegra: don't hard-code DEBUG_LL baud rate

Stop writing to the UART clock divider registers in the Tegra DEBUG_LL
code. This allows the DEBUG_LL output to use whatever baud rate was set
up by the bootloader. Some users are using higher rates than 115200.

This removes the only usage of tegra_uart_config[3], so reduce the size
allocated for that array.

Finally, fix busyuart() so that it only waits for THRE and not TEMT. For
some reason, TEMT doesn't get asserted (at least on Tegra30 Beaver) at
9600 baud, even though it does at 115200 baud. This sounds like a HW bug,
but I haven't investigated. For reference, U-Boot's serial code has
always only checked THRE, and not checked TEMT.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Paul Walmsley <pwalmsley@nvidia.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>

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ARM: tegra: fix DEBUG_LL combined with LPAE

The DEBUG_LL UART address is mapped as an MMU section, hence, the
virtual address must be section-aligned. Sections are 1MB without LPAE
and 2MB with LPAE

ARM: tegra: fix DEBUG_LL combined with LPAE

The DEBUG_LL UART address is mapped as an MMU section, hence, the
virtual address must be section-aligned. Sections are 1MB without LPAE
and 2MB with LPAE. Tegra's virtual address was only aligned to 1MB, and
hence the mapping was set up incorrectly with LPAE enabled, thus causing
a hang early during boot. Fix this by picking a different virtual address
that is aligned to 2MB.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>

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ARM: 7806/1: allow DEBUG_UNCOMPRESS for Tegra

DEBUG_UNCOMPRESS was previously disallowed for Tegra due to tegra.S's
use of global data that was not linked into the decompressor. Solve this
by declar

ARM: 7806/1: allow DEBUG_UNCOMPRESS for Tegra

DEBUG_UNCOMPRESS was previously disallowed for Tegra due to tegra.S's
use of global data that was not linked into the decompressor. Solve this
by declaring this symbol in tegra.S when it is being built into the
decompressor. For the kernel proper, leave the declaration in
mach-tegra/common.c as explained in the comment.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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ARM: tegra: move debug-macro.S to include/debug

Move Tegra's debug-macro.S over to the common debug macro directory.

Move Tegra's debug UART selection menu into ARM's Kconfig.debug, so that
all rel

ARM: tegra: move debug-macro.S to include/debug

Move Tegra's debug-macro.S over to the common debug macro directory.

Move Tegra's debug UART selection menu into ARM's Kconfig.debug, so that
all related options are selected in the same place.

Tegra's uncompress.h is left in mach-tegra/include/mach; it will be
removed whenever Tegra is converted to multi-platform.

Signed-off-by: Stephen Warren <swarren@nvidia.com>

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