Today the MHI controller name is simply cloned from the underlying
bus device (its parent), that gives the following device structure
for e.g. a MHI/PCI controller:
devices/pci0000:00/0000:00:01.2/0000:02:00.0/0000:02:00.0
devices/pci0000:00/0000:00:01.2/0000:02:00.0/0000:02:00.0/0000:02:00.0_IPCR
...

That's quite misleading/confusing and can cause device registering
issues because of duplicate dev name (e.g. if a PCI device register
two different MHI instances).

This patch changes MHI core to create indexed mhi controller names
(mhi0, mhi1...) in the same way as other busses (i2c0, usb0...).

The previous example becomes:
devices/pci0000:00/0000:00:01.2/0000:02:00.0/mhi0
devices/pci0000:00/0000:00:01.2/0000:02:00.0/mhi0/mhi0_IPCR
...
 v2: move index field at the end of mhi_controller struct (before bool)
     to avoid breaking well packed alignment.
Signed-off-by: NLoic Poulain <loic.poulain@linaro.org>
Reviewed-by: NJeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Reset MHI device channels when driver remove is called due to
module unload or any crash scenario. This will make sure that
MHI channels no longer remain enabled for transfers since the
MHI stack does not take care of this anymore after the auto-start
channels feature was removed.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Acked-by: NJakub Kicinski <kuba@kernel.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

While powering down, the device may or may not acknowledge an MHI
RESET issued by host for a graceful shutdown scenario and end up
sending an incoming data packet after tasklets have been killed.
If a rogue device sends this interrupt for a data transfer event
ring update, it can result in a tasklet getting scheduled while a
clean up is ongoing or has completed and cause access to freed
memory leading to a NULL pointer exception. Remove the interrupt
handlers for MHI event rings early on to avoid this scenario.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

mhi_power_down() does not ensure that the PM state is moved to an
inaccessible state soon enough as the system can encounter
scheduling delays till mhi_pm_disable_transition() gets called.
Additionally, if an MHI controller decides that the device is now
inaccessible and issues a power down, the register inaccessible
state is not maintained by moving from MHI_PM_LD_ERR_FATAL_DETECT
to MHI_PM_SHUTDOWN_PROCESS. This can result in bus errors if a
client driver attempted to read registers when powering down.
Close these gaps and avoid any race conditions to prevent such
activity.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Currently, there exist a set of if...else statements in the
mhi_pm_disable_transition() function which make handling system
error and disable transitions differently complex. To make that
cleaner and facilitate differences in behavior, separate these
two transitions for MHI host.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Current design allows a controller to register with MHI successfully
without the need to have any IRQs available for use. If no IRQs are
available, power up requests to MHI can fail after a successful
registration with MHI. Improve the design by checking for the number
of IRQs available sooner within the mhi_regsiter_controller() API as
it is required to be specified by the controller.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

If the host receives a mission mode event and by the time it can get
to processing it, the register accesses fail implying a connectivity
error, MHI should move to an error state. This helps avoid longer wait
times from a synchronous power up perspective and accurately reflects
the MHI execution environment and power management states.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Correct the "error_read" label to say "error_ready_state" as that
is the appropriate usage of the label.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Move MHI to a firmware download error state for a failure to find
the firmware files or to load SBL or EBL image using BHI/BHIe. This
helps detect an error state sooner and shortens the wait for a
synchronous power up timeout.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

If an mhi_power_down() is initiated after the device has entered
RDDM and a status callback was provided for it, it is possible
that another BHI interrupt fires while waiting for the MHI
RESET to be cleared. If that happens, MHI host would have moved
a "disabled" execution environment and the check to allow sending
an RDDM status callback will pass when it is should not. Add a
check to see if MHI is in an active state before proceeding.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

In some cases, the entry of device to RDDM execution environment
can occur after a significant amount of time has elapsed and a
SYS_ERROR state change event has already arrived. This can result
in scenarios where MHI controller and client drivers are unaware
of the error state of the device. Remove the check for rddm_image
when processing the SYS_ERROR state change as it is present in
mhi_pm_sys_err_handler() already and prevent further activity
until the expected RDDM execution environment change occurs or
the controller driver decides further action.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

MHI client drivers can request a device wake even if the device
may be in an error state or undergoing a shutdown. To prevent
unnecessary device wake processing, check for the device state
and bail out early so that the clients are made aware of the
device state sooner.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

MHI work is currently scheduled on the global/system workqueue and can
encounter delays on a stressed system. To avoid those unforeseen
delays which can hamper bootup or shutdown times, use a dedicated high
priority workqueue instead of the global/system workqueue.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

mhi_fw_load_sbl() function is currently used to transfer SBL or EDL
images over BHI (Boot Host Interface). Same goes with mhi_fw_load_amss()
which uses BHIe. However, the contents of these functions do not
indicate support for a specific set of images. Since these can be used
for any image download over BHI or BHIe, rename them based on the
protocol used.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

If MHI is unable to determine the execution environment during
the panic path, host must skip the RDDM download. This can happen
if the BHI offset read or the BHI_EXECENV register read fails
indicating that the underlying transport is unresponsive. Hence,
there is no need to trigger an RDDM using SYSERR or request an
SOC reset.
Suggested-by: NHemant Kumar <hemantk@codeaurora.org>
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

mhi_download_rddm_img() uses a shorter version of the word image.
Expand it and rename the function to mhi_download_rddm_image().
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

The mhi_fw_load_worker() function no longer exists. Remove its
declaration as part of code clean-up.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

The mhi_get_exec_env() APIs can be used by the controller drivers
to query the execution environment of the MHI device. Expose it
so it can be used in some scenarios to determine behavior of
controllers.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Add missing EXPORT_SYMBOL_GPL() declaration for mhi_get_mhi_state()
API.
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

There is an extra 'i' counter in the mhi_firmware_copy() function
which is unused. Remove it to clean-up code and reduce stack
space as well as improve efficiency of the function.

Fixes: cd457afb ("bus: mhi: core: Add support for downloading firmware over BHIe")
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Some MHI device drivers need to stop the channels in their driver
remove callback (e.g. module unloading), but the unprepare function
is aborted because MHI core moved the channels to suspended state
prior calling driver remove callback. This prevents the driver to
send a proper MHI RESET CHAN command to the device. Device is then
unaware of the stopped state of these channels.

This causes issue when driver tries to start the channels again (e.g.
module is reloaded), since device considers channels as already
started (inconsistent state).

Fix this by allowing channel reset when channel is suspended.
Signed-off-by: NLoic Poulain <loic.poulain@linaro.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Functions parse_ev_cfg() and parse_ch_cfg() access mhi_cntrl->mhi_dev
before it is set in function mhi_register_controller(),
use cntrl_dev instead of mhi_dev.

Fixes: 0cbf2608 ("bus: mhi: core: Add support for registering MHI controllers")
Signed-off-by: NCarl Yin <carl.yin@quectel.com>
Reviewed-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NHemant Kumar <hemantk@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

This is a generic MHI-over-PCI controller driver for MHI only devices
such as QCOM modems. For now it supports registering of Qualcomm SDX55
based PCIe modules. The MHI channels have been extracted from mhi
downstream driver.

This driver is for MHI-only devices which have all functionalities
exposed through MHI channels and accessed by the corresponding MHI
device drivers (no out-of-band communication).
Signed-off-by: NLoic Poulain <loic.poulain@linaro.org>
Reviewed-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NHemant Kumar <hemantk@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
[mani: fixed up the Makefile rule]
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

The BHI_MSMHWID and BHI_OEMPKHASH macros take a value 'n' which is
a BHI register index. If 'n' is an expression rather than a simple
value, there can be an operator precedence issue which can result
in the incorrect calculation of the register offset. Adding
parentheses around the macro parameter can prevent such issues.
Signed-off-by: NJeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: NHemant Kumar <hemantk@codeaurora.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

There is double acquisition of the pm_lock from mhi_driver_remove()
function. Remove the read_lock_bh/read_unlock_bh calls for pm_lock
taken during a call to mhi_device_put() as the lock is acquired
within the function already. This will help avoid a potential
kernel panic.

Fixes: 189ff97c ("bus: mhi: core: Add support for data transfer")
Reported-by: NShuah Khan <skhan@linuxfoundation.org>
Signed-off-by: NBhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Start MHI device channels so that transfers can be performed.
The MHI stack does not auto-start channels anymore.
Signed-off-by: NLoic Poulain <loic.poulain@linaro.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

There is really no point having an auto-start for channels.
This is confusing for the device drivers, some have to enable the
channels, others don't have... and waste resources (e.g. pre allocated
buffers) that may never be used.

This is really up to the MHI device(channel) driver to manage the state
of its channels.

While at it, let's also remove the auto-start option from ath11k mhi
controller.
Signed-off-by: NLoic Poulain <loic.poulain@linaro.org>
Acked-by: NKalle Valo <kvalo@codeaurora.org>
Reviewed-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
[mani: clubbed ath11k change]
Signed-off-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Use a more generic form for __section that requires quotes to avoid
complications with clang and gcc differences.

Remove the quote operator # from compiler_attributes.h __section macro.

Convert all unquoted __section(foo) uses to quoted __section("foo").
Also convert __attribute__((section("foo"))) uses to __section("foo")
even if the __attribute__ has multiple list entry forms.

Conversion done using the script at:

    https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.plSigned-off-by: NJoe Perches <joe@perches.com>
Reviewed-by: NNick Desaulniers <ndesaulniers@gooogle.com>
Reviewed-by: NMiguel Ojeda <ojeda@kernel.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

tid_addr is not a "pointer to (pointer to int in userspace)"; it is in
fact a "pointer to (pointer to int in userspace) in userspace".  So
sparse rightfully complains about passing a kernel pointer to
put_user().
Reported-by: Nkernel test robot <lkp@intel.com>
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 453431a5 ("mm, treewide: rename kzfree() to
kfree_sensitive()") renamed kzfree() to kfree_sensitive(),
but it left a compatibility definition of kzfree() to avoid
being too disruptive.

Since then a few more instances of kzfree() have slipped in.

Just get rid of them and remove the compatibility definition
once and for all.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If set, use the environment variable GIT_DIR to change the default .git
location of the kernel git tree.

If GIT_DIR is unset, keep using the current ".git" default.

Link: https://lkml.kernel.org/r/c5e23b45562373d632fccb8bc04e563abba4dd1d.camel@perches.comSigned-off-by: NJoe Perches <joe@perches.com>
Tested-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull timer fixes from Thomas Gleixner:
 "A time namespace fix and a matching selftest. The futex absolute
  timeouts which are based on CLOCK_MONOTONIC require time namespace
  corrected. This was missed in the original time namesapce support"

* tag 'timers-urgent-2020-10-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  selftests/timens: Add a test for futex()
  futex: Adjust absolute futex timeouts with per time namespace offset

Pull scheduler fixes from Thomas Gleixner:
 "Two scheduler fixes:

   - A trivial build fix for sched_feat() to compile correctly with
     CONFIG_JUMP_LABEL=n

   - Replace a zero lenght array with a flexible array"

* tag 'sched-urgent-2020-10-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/features: Fix !CONFIG_JUMP_LABEL case
  sched: Replace zero-length array with flexible-array

Pull perf fix from Thomas Gleixner:
 "A single fix to compute the field offset of the SNOOPX bit in the data
  source bitmask of perf events correctly"

* tag 'perf-urgent-2020-10-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: correct SNOOPX field offset

Pull locking fix from Thomas Gleixner:
 "Just a trivial fix for kernel-doc warnings"

* tag 'locking-urgent-2020-10-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/seqlocks: Fix kernel-doc warnings

Pull NTB fixes from Jon Mason.

* tag 'ntb-5.10' of git://github.com/jonmason/ntb:
  NTB: Use struct_size() helper in devm_kzalloc()
  ntb: intel: Fix memleak in intel_ntb_pci_probe
  NTB: hw: amd: fix an issue about leak system resources

Pull i2c fix from Wolfram Sang:
 "Regression fix for rc1 and stable kernels as well"

* 'i2c/for-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: core: Restore acpi_walk_dep_device_list() getting called after registering the ACPI i2c devs

Pull more cifs updates from Steve French:
 "Add support for stat of various special file types (WSL reparse points
  for char, block, fifo)"

* tag '5.10-rc-smb3-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: update internal module version number
  smb3: add some missing definitions from MS-FSCC
  smb3: remove two unused variables
  smb3: add support for stat of WSL reparse points for special file types