Add support for a new MRQ, that uses in-band messaging instead of IOVA
buffer, to retrieve the firmware version 'tag' during boot. If an
older firmware is used, that does not support the new MRQ, fall back
to the earlier implementation.

Signed-off-by: Timo Alho <talho@nvidia.com>
Acked-by: Sivaram Nair <sivaramn@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

Last two characters of the version tag that is 32 bytes long were
stripped out.

Signed-off-by: Timo Alho <talho@nvidia.com>
Acked-by: Sivaram Nair <sivaramn@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

Patch "firmware: tegra: add helper to check for supported MRQs" added
an API to check if MRQ is supported. Remove the implementation from
bpmp debugfs code in favor of that.

Signed-off-by: Timo Alho <talho@nvidia.com>
Acked-by: Sivaram Nair <sivaramn@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

Add a helper function to check that firmware is supporting a given MRQ
command.

Signed-off-by: Timo Alho <talho@nvidia.com>
Acked-by: Sivaram Nair <sivaramn@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

When returning from a system sleep state, the BPMP driver needs to
reinitialize the IVC channels used to communicate with the BPMP to
restore proper functionality.

Signed-off-by: Thierry Reding <treding@nvidia.com>

Check the variable that was most recently initialized.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x, y, f, g, e, m;
statement S1,S2,S3,S4;
@@

x = f(...);
if (\(<+...x...+>\&e\)) S1 else S2
(
x = g(...);
|
m = g(...,&x,...);
|
y = g(...);
*if (e)
 S3 else S4
)
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

The Tegra194 BPMP only implements 5 channels (4 to BPMP, 1 to CCPLEX),
and they are not placed contiguously in memory. The current channel
management in the BPMP driver does not support this.

Simplify and refactor the channel management such that only one atomic
transmit channel and one receive channel are supported, and channels
are not required to be placed contiguously in memory. The same
configuration also works on T186 so we end up with less code.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

Pull ARM SoC driver updates from Arnd Bergmann:
 "This branch contains platform-related driver updates for ARM and
  ARM64, these are the areas that bring the changes:

  New drivers:

   - driver support for Renesas R-Car V3M (R8A77970)

   - power management support for Amlogic GX

   - a new driver for the Tegra BPMP thermal sensor

   - a new bus driver for Technologic Systems NBUS

  Changes for subsystems that prefer to merge through arm-soc:

   - the usual updates for reset controller drivers from Philipp Zabel,
     with five added drivers for SoCs in the arc, meson, socfpa,
     uniphier and mediatek families

   - updates to the ARM SCPI and PSCI frameworks, from Sudeep Holla,
     Heiner Kallweit and Lorenzo Pieralisi

  Changes specific to some ARM-based SoC

   - the Freescale/NXP DPAA QBMan drivers from PowerPC can now work on
     ARM as well

   - several changes for power management on Broadcom SoCs

   - various improvements on Qualcomm, Broadcom, Amlogic, Atmel,
     Mediatek

   - minor Cleanups for Samsung, TI OMAP SoCs"

[ NOTE! This doesn't work without the previous ARM SoC device-tree pull,
  because the R8A77970 driver is missing a header file that came from
  that pull.

  The fact that this got merged afterwards only fixes it at this point,
  and bisection of that driver will fail if/when you walk into the
  history of that driver.           - Linus ]

* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (96 commits)
  soc: amlogic: meson-gx-pwrc-vpu: fix power-off when powered by bootloader
  bus: add driver for the Technologic Systems NBUS
  memory: omap-gpmc: Remove deprecated gpmc_update_nand_reg()
  soc: qcom: remove unused label
  soc: amlogic: gx pm domain: add PM and OF dependencies
  drivers/firmware: psci_checker: Add missing destroy_timer_on_stack()
  dt-bindings: power: add amlogic meson power domain bindings
  soc: amlogic: add Meson GX VPU Domains driver
  soc: qcom: Remote filesystem memory driver
  dt-binding: soc: qcom: Add binding for rmtfs memory
  of: reserved_mem: Accessor for acquiring reserved_mem
  of/platform: Generalize /reserved-memory handling
  soc: mediatek: pwrap: fix fatal compiler error
  soc: mediatek: pwrap: fix compiler errors
  arm64: mediatek: cleanup message for platform selection
  soc: Allow test-building of MediaTek drivers
  soc: mediatek: place Kconfig for all SoC drivers under menu
  soc: mediatek: pwrap: add support for MT7622 SoC
  soc: mediatek: pwrap: add common way for setup CS timing extenstion
  soc: mediatek: pwrap: add MediaTek MT6380 as one slave of pwrap
  ..

workqueue: kill off ACCESS_ONCE()

For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't currently harmful.

However, for some features it is necessary to instrument reads and
writes separately, which is not possible with ACCESS_ONCE(). This
distinction is critical to correct operation.

It's possible to transform the bulk of kernel code using the Coccinelle
script below. However, this doesn't handle comments, leaving references
to ACCESS_ONCE() instances which have been removed. As a preparatory
step, this patch converts the Tegra IVC code and comments to use
{READ,WRITE}_ONCE() consistently.

----
virtual patch

@ depends on patch @
expression E1, E2;
@@

- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)

@ depends on patch @
expression E;
@@

- ACCESS_ONCE(E)
+ READ_ONCE(E)
----

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-3-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Tegra power management firmware running on the co-processor (BPMP)
implements a simple pseudo file system akin to debugfs. The file
system can be used for debugging purposes to examine and change the
status of selected resources controlled by the firmware (such as
clocks, resets, voltages, powergates, ...).

Add support to "mirror" the firmware's file system to debugfs. At
boot, query firmware for a list of all possible files and create
corresponding debugfs entries. Read/write of individual files is
implemented by sending a Message ReQuest (MRQ) that passes the full
file path name and data to firmware via DRAM.

Signed-off-by: Timo Alho <talho@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>