Implement a FSI master using GPIO.  Will generate FSI protocol for
read and write commands to particular addresses.  Sends master command
and waits for and decodes a slave response.

Includes changes from Edward A. James <eajames@us.ibm.com> and Jeremy
Kerr <jk@ozlabs.org>.
Signed-off-by: NEdward A. James <eajames@us.ibm.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NChristopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add info for sysfs scan file in Documentaiton ABI/testing
Signed-off-by: NChristopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This change implements error handling in the FSI core, by cleaining up
and retrying failed operations, using the SISC, TERM and BREAK
facilities.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NChristopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Trace low level read and write FSI bus operations.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NChristopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Allow drivers to access the slave address ranges.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NChristopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This change adds a 'raw' file for reads & writes, and a 'term' file for
the TERM command, and a 'break' file for issuing a BREAK.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NChristopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add driver_register and driver_unregister wrappers for FSI.
Signed-off-by: NChristopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add fsi master gpio device tree binding documentation.

Includes changes from Jeremy Kerr <jk@ozlabs.org>.
Signed-off-by: NChristopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Allow a master to undo a previous scan.  Should a master scan a bus
twice it will need to ensure it doesn't double register any
previously detected device.
Signed-off-by: NChristopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
----
v7 - Unscan when unregistering master
   - Remove leading '__'s from function names
   - Return fail state for sysfs rescan file
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This change introduces the fsi device API: simple read, write and peek
accessors for the devices' address spaces.

Includes contributions from Christopher Bostic
<cbostic@linux.vnet.ibm.com> and Edward A. James <eajames@us.ibm.com>.
Signed-off-by: NEdward A. James <eajames@us.ibm.com>
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NChristopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Now that we have fsi_slave devices, scan each for endpoints, and
register them on the fsi bus.

Includes contributions from Christopher Bostic
<cbostic@linux.vnet.ibm.com>.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NChristopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Set CFAM to appropriate ID so that the controlling master can manage
link memory ranges.  Add slave engine register definitions.

Includes changes from Jeremy Kerr <jk@ozlabs.org>.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NChristopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Implement fsi_slave_init: if we can read a chip ID, create fsi_slave
devices and register with the driver core.

Includes changes from Christopher Bostic <cbostic@linux.vnet.ibm.com>.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NChristopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Enable each link and send a break command, and try to detect a slave by
reading from the SMODE register.
Signed-off-by: NChristopher Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Introduce functions to perform reads/writes on the slave address space;
these simply pass the request on the slave's master with the correct
link and slave ID.

We implement these on top of similar helpers for the master.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NChris Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add a little helper for crc4 calculations. This works 4-bits-at-a-time,
using a simple table approach.

We will need this in the FSI core code, as well as any master
implementations that need to calculate CRCs in software.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NChris Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When a new fsi master is added, we will need to scan its links, and
slaves attached to those links. This change introduces a little shell to
iterate the links, which we will populate with the actual slave scan in
a later change.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NChris Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add the initial fsi slave device, which is private to the core code.
This will be a child of the master, and parent to endpoint devices.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NChris Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add a `struct fsi_master` to represent a FSI master controller.

FSI master drivers register one of these structs to provide
device-specific of the standard operations: read/write/term/break and
link control.

Includes changes from Edward A. James <eajames@us.ibm.com> & Jeremy Kerr
<jk@ozlabs.org>.
Signed-off-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NChris Bostic <cbostic@linux.vnet.ibm.com>
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Disable Network file system support.

Reviewed-at: https://android-review.googlesource.com/#/c/409559/Signed-off-by: NRoberto Pereira <rpere@google.com>
[AmitP: cherry-picked this change from Android common kernel
        and updated commit message]
Signed-off-by: NAmit Pundir <amit.pundir@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add CONFIG_CGROUP_BPF as a default configuration in android base config
since it is used to replace XT_QTAGUID in future.

Reviewed-at: https://android-review.googlesource.com/#/c/400374/Signed-off-by: NChenbo Feng <fengc@google.com>
[AmitP: cherry-picked this change from Android common kernel]
Signed-off-by: NAmit Pundir <amit.pundir@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This adds CONFIG_MODULES, CONFIG_MODULE_UNLOAD, and CONFIG_MODVERSIONS
which are required by the O release.

Reviewed-at: https://android-review.googlesource.com/#/c/364554/Signed-off-by: NGreg Kroah-Hartman <gregkh@google.com>
[AmitP: cherry-picked this change from Android common kernel]
Signed-off-by: NAmit Pundir <amit.pundir@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This adds CONFIG_IKCONFIG and CONFIG_IKCONFIG_PROC options, which are a
requirement for the O release.

Reviewed-at: https://android-review.googlesource.com/#/c/364553/Signed-off-by: NGreg Kroah-Hartman <gregkh@google.com>
[AmitP: cherry-picked this change from Android common kernel]
Signed-off-by: NAmit Pundir <amit.pundir@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Enable CPU domain PAN to ensure that normal kernel accesses are
unable to access userspace addresses.

Reviewed-at: https://android-review.googlesource.com/#/c/334035/Signed-off-by: NSami Tolvanen <samitolvanen@google.com>
[AmitP: cherry-picked this change from Android common kernel, updated
        the commit message and re-placed the CONFIG_STRICT_KERNEL_RWX
        config in sorted order]
Signed-off-by: NAmit Pundir <amit.pundir@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Turn off the two kernel configs to disable related system ABI.

Reviewed-at: https://android-review.googlesource.com/#/c/264976/Signed-off-by: NMax Shi <meixuanshi@google.com>
[AmitP: cherry-picked this change from Android common kernel]
Signed-off-by: NAmit Pundir <amit.pundir@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Enable PAN emulation using TTBR0_EL1 switching.

Reviewed-at: https://android-review.googlesource.com/#/c/325997/Signed-off-by: NSami Tolvanen <samitolvanen@google.com>
[AmitP: cherry-picked this change from Android common kernel
        and updated the commit message]
Signed-off-by: NAmit Pundir <amit.pundir@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If compiler has stack protector support, set
CONFIG_CC_STACKPROTECTOR_STRONG.

Reviewed-at: https://android-review.googlesource.com/#/c/238388/Signed-off-by: NJeff Vander Stoep <jeffv@google.com>
[AmitP: cherry-picked this change from Android common kernel]
Signed-off-by: NAmit Pundir <amit.pundir@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add debug unit on Qualcomm msm8916 based platforms, including the
DragonBoard 410c board.
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Reviewed-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: NAndy Gross <andy.gross@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Bind debug module driver for Hi6220.
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Reviewed-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: NWei Xu <xuwei5@hisilicon.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Coresight includes debug module and usually the module connects with CPU
debug logic. ARMv8 architecture reference manual (ARM DDI 0487A.k) has
description for related info in "Part H: External Debug".

Chapter H7 "The Sample-based Profiling Extension" introduces several
sampling registers, e.g. we can check program counter value with
combined CPU exception level, secure state, etc. So this is helpful for
analysis CPU lockup scenarios, e.g. if one CPU has run into infinite
loop with IRQ disabled. In this case the CPU cannot switch context and
handle any interrupt (including IPIs), as the result it cannot handle
SMP call for stack dump.

This patch is to enable coresight debug module, so firstly this driver
is to bind apb clock for debug module and this is to ensure the debug
module can be accessed from program or external debugger. And the driver
uses sample-based registers for debug purpose, e.g. when system triggers
panic, the driver will dump program counter and combined context
registers (EDCIDSR, EDVIDSR); by parsing context registers so can
quickly get to know CPU secure state, exception level, etc.

Some of the debug module registers are located in CPU power domain, so
this requires the CPU power domain stays on when access related debug
registers, but the power management for CPU power domain is quite
dependent on SoC integration for power management. For the platforms
which with sane power controller implementations, this driver follows
the method to set EDPRCR to try to pull the CPU out of low power state
and then set 'no power down request' bit so the CPU has no chance to
lose power.

If the SoC has not followed up this design well for power management
controller, the user should use the command line parameter or sysfs
to constrain all or partial idle states to ensure the CPU power
domain is enabled and access coresight CPU debug component safely.
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Reviewed-by: NSuzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This is refactor to add function of_coresight_get_cpu(), so it's used to
retrieve CPU id for coresight component. Finally can use it as a common
function for multiple places.
Suggested-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The of_get_coresight_platform_data iterates over the possible CPU nodes
to find a given cpu phandle. However it does not drop the reference
to the node pointer returned by the of_get_coresight_platform_data.

This patch also introduces another minor fix is to use
of_cpu_device_node_get() to replace of_get_cpu_node().

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NSuzuki K Poulose <suzuki.poulose@arm.com>
[Leo: minor tweaks for of_get_coresight_platform_data]
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Update document file entries for Coresight debug module.
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add coresight_cpu_debug.enable to kernel-parameters.txt, this flag is
used to enable/disable the CPU sampling based debugging.
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add detailed documentation for Coresight CPU debug driver, which
contains the info for driver implementation, Mike Leach excellent
summary for "clock and power domain". At the end some examples on how
to enable the debugging functionality are provided.
Suggested-by: NMike Leach <mike.leach@linaro.org>
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

According to ARMv8 architecture reference manual (ARM DDI 0487A.k)
Chapter 'Part H: External debug', the CPU can integrate debug module
and it can support self-hosted debug and external debug. Especially
for supporting self-hosted debug, this means the program can access
the debug module from mmio region; and usually the mmio region is
integrated with coresight.

So add document for binding debug component, includes binding to APB
clock; and also need specify the CPU node which the debug module is
dedicated to specific CPU.
Suggested-by: NMike Leach <mike.leach@linaro.org>
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Reviewed-by: NSuzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Before making any DMA API calls, the ETR driver should really be setting
its masks to ensure that DMA is possible. Especially since it can
address more than the 32-bit default mask set by the AMBA bus code.
Signed-off-by: NRobin Murphy <robin.murphy@arm.com>
Tested-by: NSuzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Delete a character in this description for a condition check.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Omit an extra message for a memory allocation failure in this function.

This issue was detected by using the Coccinelle software.

Link: http://events.linuxfoundation.org/sites/events/files/slides/LCJ16-Refactor_Strings-WSang_0.pdfSigned-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Almost low level functions from open firmware have used const to
qualify device_node structures, so add const for device_node
parameters in of_coresight related functions.
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>