332 Commits

Author SHA1 Message Date
Manivannan Sadhasivam
ee0360b20b bus: mhi: ep: Add support for registering MHI endpoint client drivers
This commit adds support for registering MHI endpoint client drivers
with the MHI endpoint stack. MHI endpoint client drivers bind to one
or more MHI endpoint devices inorder to send and receive the upper-layer
protocol packets like IP packets, modem control messages, and
diagnostics messages over MHI bus.

Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220405135754.6622-3-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-26 13:17:40 +02:00
Manivannan Sadhasivam
d434743e5c bus: mhi: ep: Add support for registering MHI endpoint controllers
This commit adds support for registering MHI endpoint controller drivers
with the MHI endpoint stack. MHI endpoint controller drivers manage
the interaction with the host machines (such as x86). They are also the
MHI endpoint bus master in charge of managing the physical link between
the host and endpoint device. Eventhough the MHI spec is bus agnostic,
the current implementation is entirely based on PCIe bus.

The endpoint controller driver encloses all information about the
underlying physical bus like PCIe. The registration process involves
parsing the channel configuration and allocating an MHI EP device.

Channels used in the endpoint stack follows the perspective of the MHI
host stack. i.e.,

UL - From host to endpoint
DL - From endpoint to host

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220405135754.6622-2-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-26 13:17:40 +02:00
Slark Xiao
17e6ff4937 bus: mhi: host: Add support for Cinterion MV32-WA/MV32-WB
MV32-WA is designed based on Qualcomm SDX62, and
MV32-WB is designed based on QUalcomm SDX65. Both
products' enumeration would align with previous
product MV31-W.So we merge MV31 and MV32 to MV3X
for some common settings.

Signed-off-by: Slark Xiao <slark_xiao@163.com>
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://lore.kernel.org/r/20220421092141.3984-1-slark_xiao@163.com
[mani: removed the fixes tag that's not needed]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-23 19:06:58 +05:30
Bhaumik Bhatt
d126bfeaf7 bus: mhi: host: Optimize and update MMIO register write method
As of now, MMIO writes done after ready state transition use the
mhi_write_reg_field() API even though the whole register is being
written in most cases. Optimize this process by using mhi_write_reg()
API instead for those writes and use the mhi_write_reg_field()
API for MHI config registers only.

Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Signed-off-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/1650304226-11080-3-git-send-email-quic_jhugo@quicinc.com
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-23 18:57:32 +05:30
Bhaumik Bhatt
0bca889fd6 bus: mhi: host: Bail on writing register fields if read fails
Helper API to write register fields relies on successful reads
of the register/address prior to the write. Bail out if a failure
is seen when reading the register before the actual write is
performed.

Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Signed-off-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/1650304226-11080-2-git-send-email-quic_jhugo@quicinc.com
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-23 18:57:32 +05:30
Jeffrey Hugo
36e5505dfb bus: mhi: host: Wait for ready state after reset
After the device has signaled the end of reset by clearing the reset bit,
it will automatically reinit MHI and the internal device structures.  Once
That is done, the device will signal it has entered the ready state.

Signaling the ready state involves sending an interrupt (MSI) to the host
which might cause IOMMU faults if it occurs at the wrong time.

If the controller is being powered down, and possibly removed, then the
reset flow would only wait for the end of reset.  At which point, the host
and device would start a race.  The host may complete its reset work, and
remove the interrupt handler, which would cause the interrupt to be
disabled in the IOMMU.  If that occurs before the device signals the ready
state, then the IOMMU will fault since it blocked an interrupt.  While
harmless, the fault would appear like a serious issue has occurred so let's
silence it by making sure the device hits the ready state before the host
completes its reset processing.

Signed-off-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Reviewed-by: Hemant Kumar <quic_hemantk@quicinc.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/1650302562-30964-1-git-send-email-quic_jhugo@quicinc.com
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-23 18:57:32 +05:30
Jeffrey Hugo
95c33ae41b bus: mhi: host: Add soc_reset sysfs
The MHI bus supports a standardized hardware reset, which is known as the
"SoC Reset".  This reset is similar to the reset sysfs for PCI devices -
a hardware mechanism to reset the state back to square one.

The MHI SoC Reset is described in the spec as a reset of last resort.  If
some unrecoverable error has occurred where other resets have failed, SoC
Reset is the "big hammer" that ungracefully resets the device.  This is
effectivly the same as yanking the power on the device, and reapplying it.
However, depending on the nature of the particular issue, the underlying
transport link may remain active and configured.  If the link remains up,
the device will flag a MHI system error early in the boot process after
the reset is executed, which allows the MHI bus to process a fatal error
event, and clean up appropiately.

While the SoC Reset is generally intended as a means of recovery when all
else has failed, it can be useful in non-error scenarios.  For example,
if the device loads firmware from the host filesystem, the device may need
to be fully rebooted inorder to pick up the new firmware.  In this
scenario, the system administrator may use the soc_reset sysfs to cause
the device to pick up the new firmware that the admin placed on the
filesystem.

Signed-off-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Reviewed-by: Bhaumik Bhatt <quic_bbhatt@quicinc.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/1650302327-30439-1-git-send-email-quic_jhugo@quicinc.com
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-23 18:57:32 +05:30
Manivannan Sadhasivam
89ad19bea6 bus: mhi: host: pci_generic: Sort mhi_pci_id_table based on the PID
Sorting this way helps in identifying the products of vendors. There is no
sorting required for VID and the new VID should be added as the last entry.

Let's also add a note clarifying this.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Daniele Palmas <dnlplm@gmail.com>
Link: https://lore.kernel.org/r/20220411133428.42165-1-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-23 18:57:31 +05:30
Jeffrey Hugo
e565d3efd8 bus: mhi: host: Use cached values for calculating the shared write pointer
mhi_recycle_ev_ring() computes the shared write pointer for the ring
(ctxt_wp) using a read/modify/write pattern where the ctxt_wp value in the
shared memory is read, incremented, and written back.  There are no checks
on the read value, it is assumed that it is kept in sync with the locally
cached value.  Per the MHI spec, this is correct.  The device should only
read ctxt_wp, never write it.

However, there are devices in the wild that violate the spec, and can
update the ctxt_wp in a specific scenario.  This can cause corruption, and
violate the above assumption that the ctxt_wp is in sync with the cached
value.

This can occur when the device has loaded firmware from the host, and is
transitioning from the SBL EE to the AMSS EE.  As part of shutting down
SBL, the SBL flushes it's local MHI context to the shared memory since
the local context will not persist across an EE change.  In the case of
the event ring, SBL will flush its entire context, not just the parts that
it is allowed to update.  This means SBL will write to ctxt_wp, and
possibly corrupt it.

An example:

Host				Device
----				---
Update ctxt_wp to 0x1f0
				SBL observes 0x1f0
Update ctxt_wp to 0x0
				Starts transition to AMSS EE
				Context flush, writes 0x1f0 to ctxt_wp
Update ctxt_wp to 0x200
Update ctxt_wp to 0x210
				AMSS observes 0x210
				0x210 exceeds ring size
				AMSS signals syserr

The reason the ctxt_wp goes off the end of the ring is that the rollover
check is only performed on the cached wp, which is out of sync with
ctxt_wp.

Since the host is the authority of the value of ctxt_wp per the MHI spec,
we can fix this issue by not reading ctxt_wp from the shared memory, and
instead compute it based on the cached value.  If SBL corrupts ctxt_wp,
the host won't observe it, and will correct the value at some point later.

Signed-off-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Reviewed-by: Hemant Kumar <quic_hemantk@quicinc.com>
Reviewed-by: Bhaumik Bhatt <quic_bbhatt@quicinc.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/1649868113-18826-1-git-send-email-quic_jhugo@quicinc.com
[mani: used the quicinc domain for Hemant and Bhaumik]
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-23 18:57:31 +05:30
Manivannan Sadhasivam
c38f83bae4 bus: mhi: host: pci_generic: Flush recovery worker during freeze
It is possible that the recovery work might be running while the freeze
gets executed (during hibernation etc.,). Currently, we don't powerdown
the stack if it is not up but if the recovery work completes after freeze,
then the device will be up afterwards. This will not be a sane situation.

So let's flush the recovery worker before trying to powerdown the device.

Cc: stable@vger.kernel.org
Fixes: 5f0c2ee1fe8d ("bus: mhi: pci-generic: Fix hibernation")
Reported-by: Bhaumik Vasav Bhatt <quic_bbhatt@quicinc.com>
Reviewed-by: Bhaumik Vasav Bhatt <quic_bbhatt@quicinc.com>
Link: https://lore.kernel.org/r/20220408150039.17297-1-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-13 13:11:19 +05:30
Manivannan Sadhasivam
e64d5fa504 bus: mhi: host: pci_generic: Add missing poweroff() PM callback
During hibernation process, once thaw() stage completes, the MHI endpoint
devices will be in M0 state post recovery. After that, the devices will be
powered down so that the system can enter the target sleep state. During
this stage, the PCI core will put the devices in D3hot. But this transition
is allowed by the MHI spec. The devices can only enter D3hot when it is in
M3 state.

So for fixing this issue, let's add the poweroff() callback that will get
executed before putting the system in target sleep state during
hibernation. This callback will power down the device properly so that it
could be restored during restore() or thaw() stage.

Cc: stable@vger.kernel.org
Fixes: 5f0c2ee1fe8d ("bus: mhi: pci-generic: Fix hibernation")
Reported-by: Hemant Kumar <quic_hemantk@quicinc.com>
Suggested-by: Hemant Kumar <quic_hemantk@quicinc.com>
Link: https://lore.kernel.org/r/20220405125907.5644-1-manivannan.sadhasivam@linaro.org
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-13 13:11:11 +05:30
Manivannan Sadhasivam
5d4be19cbe bus: mhi: ep: Add uevent support for module autoloading
Add uevent support to MHI endpoint bus so that the client drivers can be
autoloaded by udev when the MHI endpoint devices gets created. The client
drivers are expected to provide MODULE_DEVICE_TABLE with the MHI id_table
struct so that the alias can be exported.

The MHI endpoint reused the mhi_device_id structure of the MHI bus.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:51 +05:30
Manivannan Sadhasivam
5fb83d97aa bus: mhi: ep: Add support for suspending and resuming channels
Add support for suspending and resuming the channels in MHI endpoint stack.
The channels will be moved to the suspended state during M3 state
transition and will be resumed during M0 transition.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:51 +05:30
Manivannan Sadhasivam
f2a72d2410 bus: mhi: ep: Add support for queueing SKBs to the host
Add support for queueing SKBs to the host over the transfer ring of the
relevant channel. The mhi_ep_queue_skb() API will be used by the client
networking drivers to queue the SKBs to the host over MHI bus.

The host will add ring elements to the transfer ring periodically for
the device and the device will write SKBs to the ring elements. If a
single SKB doesn't fit in a ring element (TRE), it will be placed in
multiple ring elements and the overflow event will be sent for all ring
elements except the last one. For the last ring element, the EOT event
will be sent indicating the packet boundary.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:51 +05:30
Manivannan Sadhasivam
494a6f6393 bus: mhi: ep: Add support for processing channel rings
Add support for processing the channel rings from host. For the channel
ring associated with DL channel, the xfer callback will simply invoked.
For the case of UL channel, the ring elements will be read in a buffer
till the write pointer and later passed to the client driver using the
xfer callback.

The client drivers should provide the callbacks for both UL and DL
channels during registration.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:51 +05:30
Manivannan Sadhasivam
20c01fde1b bus: mhi: ep: Add support for reading from the host
Data transfer between host and the ep device happens over the transfer
ring associated with each bi-directional channel pair. Host defines the
transfer ring by allocating memory for it. The read and write pointer
addresses of the transfer ring are stored in the channel context.

Once host places the elements in the transfer ring, it increments the
write pointer and rings the channel doorbell. Device will receive the
doorbell interrupt and will process the transfer ring elements.

This commit adds support for reading the transfer ring elements from
the transfer ring till write pointer, incrementing the read pointer and
finally sending the completion event to the host through corresponding
event ring.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:51 +05:30
Manivannan Sadhasivam
2b231a40e9 bus: mhi: ep: Add support for processing command rings
Add support for processing the command rings. Command ring is used by the
host to issue channel specific commands to the ep device. Following
commands are supported:

1. Start channel
2. Stop channel
3. Reset channel

Once the device receives the command doorbell interrupt from host, it
executes the command and generates a command completion event to the
host in the primary event ring.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:51 +05:30
Manivannan Sadhasivam
1b54f3e8b4 bus: mhi: ep: Add support for handling SYS_ERR condition
Add support for handling SYS_ERR (System Error) condition in the MHI
endpoint stack. The SYS_ERR flag will be asserted by the endpoint device
when it detects an internal error. The host will then issue reset and
reinitializes MHI to recover from the error state.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:51 +05:30
Manivannan Sadhasivam
2ee735c173 bus: mhi: ep: Add support for handling MHI_RESET
Add support for handling MHI_RESET in MHI endpoint stack. MHI_RESET will
be issued by the host during shutdown and during error scenario so that
it can recover the endpoint device without restarting the whole device.

MHI_RESET handling involves resetting the internal MHI registers, data
structures, state machines, resetting all channels/rings and setting
MHICTRL.RESET bit to 0. Additionally the device will also move to READY
state if the reset was due to SYS_ERR.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:51 +05:30
Manivannan Sadhasivam
c6dba89242 bus: mhi: ep: Add support for powering down the MHI endpoint stack
Add support for MHI endpoint power_down that includes stopping all
available channels, destroying the channels, resetting the event and
transfer rings and freeing the host cache.

The stack will be powered down whenever the physical bus link goes down.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:50 +05:30
Manivannan Sadhasivam
7de7780c43 bus: mhi: ep: Add support for powering up the MHI endpoint stack
Add support for MHI endpoint power_up that includes initializing the MMIO
and rings, caching the host MHI registers, and setting the MHI state to M0.
After registering the MHI EP controller, the stack has to be powered up
for usage.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:50 +05:30
Manivannan Sadhasivam
b6c52d410c bus: mhi: ep: Add support for processing MHI endpoint interrupts
Add support for processing MHI endpoint interrupts such as control
interrupt, command interrupt and channel interrupt from the host.

The interrupts will be generated in the endpoint device whenever host
writes to the corresponding doorbell registers. The doorbell logic
is handled inside the hardware internally.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:50 +05:30
Manivannan Sadhasivam
484e04faa8 bus: mhi: ep: Add support for managing MHI state machine
Add support for managing the MHI state machine by controlling the state
transitions. Only the following MHI state transitions are supported:

1. Ready state
2. M0 state
3. M3 state
4. SYS_ERR state

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:50 +05:30
Manivannan Sadhasivam
6f7cb6e788 bus: mhi: ep: Add support for sending events to the host
Add support for sending the events to the host over MHI bus from the
endpoint. Following events are supported:

1. Transfer completion event
2. Command completion event
3. State change event
4. Execution Environment (EE) change event

An event is sent whenever an operation has been completed in the MHI EP
device. Event is sent using the MHI event ring and additionally the host
is notified using an IRQ if required.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:50 +05:30
Manivannan Sadhasivam
edf549e7b2 bus: mhi: ep: Add support for ring management
Add support for managing the MHI ring. The MHI ring is a circular queue
of data structures used to pass the information between host and the
endpoint.

MHI support 3 types of rings:

1. Transfer ring
2. Event ring
3. Command ring

All rings reside inside the host memory and the MHI EP device maps it to
the device memory using blocks like PCIe iATU. The mapping is handled in
the MHI EP controller driver itself.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:50 +05:30
Manivannan Sadhasivam
37867094fa bus: mhi: ep: Add support for managing MMIO registers
Add support for managing the Memory Mapped Input Output (MMIO) registers
of the MHI bus. All MHI operations are carried out using the MMIO registers
by both host and the endpoint device.

The MMIO registers reside inside the endpoint device memory (fixed
location based on the platform) and the address is passed by the MHI EP
controller driver during its registration.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:50 +05:30
Manivannan Sadhasivam
03f44035a5 bus: mhi: ep: Add support for creating and destroying MHI EP devices
This commit adds support for creating and destroying MHI endpoint devices.
The MHI endpoint devices binds to the MHI endpoint channels and are used
to transfer data between MHI host and endpoint device.

There is a single MHI EP device for each channel pair. The devices will be
created when the corresponding channels has been started by the host and
will be destroyed during MHI EP power down and reset.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:50 +05:30
Manivannan Sadhasivam
36b7cae6a0 bus: mhi: ep: Add support for registering MHI endpoint client drivers
This commit adds support for registering MHI endpoint client drivers
with the MHI endpoint stack. MHI endpoint client drivers bind to one
or more MHI endpoint devices inorder to send and receive the upper-layer
protocol packets like IP packets, modem control messages, and
diagnostics messages over MHI bus.

Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:50 +05:30
Manivannan Sadhasivam
0cf3534783 bus: mhi: ep: Add support for registering MHI endpoint controllers
This commit adds support for registering MHI endpoint controller drivers
with the MHI endpoint stack. MHI endpoint controller drivers manage
the interaction with the host machines (such as x86). They are also the
MHI endpoint bus master in charge of managing the physical link between
the host and endpoint device. Eventhough the MHI spec is bus agnostic,
the current implementation is entirely based on PCIe bus.

The endpoint controller driver encloses all information about the
underlying physical bus like PCIe. The registration process involves
parsing the channel configuration and allocating an MHI EP device.

Channels used in the endpoint stack follows the perspective of the MHI
host stack. i.e.,

UL - From host to endpoint
DL - From endpoint to host

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
2022-04-04 10:17:50 +05:30
Manivannan Sadhasivam
3a1b8e281a bus: mhi: Make mhi_state_str[] array static inline and move to common.h
mhi_state_str[] array could be used by MHI endpoint stack also. So let's
make the array as "static inline function" and move it inside the
"common.h" header so that the endpoint stack could also make use of it.

Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220301160308.107452-11-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-18 14:02:55 +01:00
Manivannan Sadhasivam
8485149c7a bus: mhi: Move common MHI definitions out of host directory
Move the common MHI definitions in host "internal.h" to "common.h" so
that the endpoint code can make use of them. This also avoids
duplicating the definitions in the endpoint stack.

Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220301160308.107452-10-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-18 14:02:55 +01:00
Manivannan Sadhasivam
84f5f31f11 bus: mhi: host: Rename "struct mhi_tre" to "struct mhi_ring_element"
Structure "struct mhi_tre" is representing a generic MHI ring element and
not specifically a Transfer Ring Element (TRE). Fix the naming.

Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220301160308.107452-9-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-18 14:02:55 +01:00
Manivannan Sadhasivam
792ba32184 bus: mhi: Cleanup the register definitions used in headers
Cleanup includes:

1. Using the GENMASK macro for masks
2. Removing brackets for single values
3. Using lowercase for hex values
4. Using two digits for hex values where applicable
5. Aligning the defines on same column

Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220301160308.107452-8-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-18 14:02:54 +01:00
Manivannan Sadhasivam
ba1d2b86b6 bus: mhi: Use bitfield operations for handling DWORDs of ring elements
Instead of using the hardcoded bits in DWORD definitions, let's use the
bitfield operations to make it more clear how the DWORDs are structured.

Suggested-by: Alex Elder <elder@linaro.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220301160308.107452-7-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-18 14:02:54 +01:00
Manivannan Sadhasivam
d28cab4d4a bus: mhi: Use bitfield operations for register read and write
Functions like mhi_read_reg_field(), mhi_poll_reg_field() and
mhi_write_reg_field() could be modified to not depend on the shift value
passed as an argument. Instead, the bitfield operation could be used to
extract the shift value from the mask itself.

This eliminates the need to define _SHIFT (and _SHFT) macros and
simplifies the code a bit. For shift values those cannot be determined
during build time, "__ffs()" helper is used find the shift value during
runtime.

While at it, let's also get rid of 32-bit masks like CHDBOFF_CHDBOFF_MASK
by doing the full 32-bit register read.

Suggested-by: Alex Elder <elder@linaro.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220301160308.107452-6-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-18 14:02:54 +01:00
Manivannan Sadhasivam
a0f5a63066 bus: mhi: Move host MHI code to "host" directory
In preparation of the endpoint MHI support, let's move the host MHI code
to its own "host" directory and adjust the toplevel MHI Kconfig & Makefile.

While at it, let's also move the "pci_generic" driver to "host" directory
as it is a host MHI controller driver.

Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220301160308.107452-5-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-18 14:02:54 +01:00
Paul Davey
ed2d980503 bus: mhi: Fix MHI DMA structure endianness
The MHI driver does not work on big endian architectures.  The
controller never transitions into mission mode.  This appears to be due
to the modem device expecting the various contexts and transfer rings to
have fields in little endian order in memory, but the driver constructs
them in native endianness.

Fix MHI event, channel and command contexts and TRE handling macros to
use explicit conversion to little endian.  Mark fields in relevant
structures as little endian to document this requirement.

Fixes: a6e2e3522f29 ("bus: mhi: core: Add support for PM state transitions")
Fixes: 6cd330ae76ff ("bus: mhi: core: Add support for ringing channel/event ring doorbells")
Cc: stable@vger.kernel.org
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Paul Davey <paul.davey@alliedtelesis.co.nz>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220301160308.107452-4-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-18 14:02:54 +01:00
Paul Davey
64f93a9a27 bus: mhi: Fix pm_state conversion to string
On big endian architectures the mhi debugfs files which report pm state
give "Invalid State" for all states.  This is caused by using
find_last_bit which takes an unsigned long* while the state is passed in
as an enum mhi_pm_state which will be of int size.

Fix by using __fls to pass the value of state instead of find_last_bit.

Also the current API expects "mhi_pm_state" enumerator as the function
argument but the function only works with bitmasks. So as Alex suggested,
let's change the argument to u32 to avoid confusion.

Fixes: a6e2e3522f29 ("bus: mhi: core: Add support for PM state transitions")
Cc: stable@vger.kernel.org
[mani: changed the function argument to u32]
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Paul Davey <paul.davey@alliedtelesis.co.nz>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220301160308.107452-3-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-18 14:02:54 +01:00
Yonglin Tan
2413ffbf19 bus: mhi: pci_generic: Add mru_default for Quectel EM1xx series
For default mechanism, the driver uses default MRU 3500 if mru_default
is not initialized. The Qualcomm configured the MRU size to 32768 in the
WWAN device FW. So, we align the driver setting with Qualcomm FW setting.

Link: https://lore.kernel.org/r/MEYP282MB2374EE345DADDB591AFDA6AFFD2E9@MEYP282MB2374.AUSP282.PROD.OUTLOOK.COM
Fixes: ac4bf60bbaa0 ("bus: mhi: pci_generic: Introduce quectel EM1XXGR-L support")
Cc: stable@vger.kernel.org
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Yonglin Tan <yonglin.tan@outlook.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220301160308.107452-2-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-18 14:02:54 +01:00
Slark Xiao
05daa805a8 bus: mhi: pci_generic: Add mru_default for Cinterion MV31-W
For default mechanism, product would use default MRU 3500 if
they didn't define it. But for Cinterion MV31-W, there is a known
issue which MRU 3500 would lead to data connection lost.
So we align it with Qualcomm default MRU settings.

Link: https://lore.kernel.org/r/20220119102519.5342-1-slark_xiao@163.com
[mani: Modified the commit message to reflect Cinterion MV31-W and CCed stable]
Fixes: 87693e092bd0 ("bus: mhi: pci_generic: Add Cinterion MV31-W PCIe to MHI")
Cc: stable@vger.kernel.org # v5.14 +
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Slark Xiao <slark_xiao@163.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220205135731.157871-3-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-06 13:19:46 +01:00
Slark Xiao
a0572cea88 bus: mhi: pci_generic: Add mru_default for Foxconn SDX55
For default mechanism, product would use default MRU 3500 if
they didn't define it. But for Foxconn SDX55, there is a known
issue which MRU 3500 would lead to data connection lost.
So we align it with Qualcomm default MRU settings.

Link: https://lore.kernel.org/r/20220119101213.5008-1-slark_xiao@163.com
[mani: Added pci_generic prefix to subject and CCed stable]
Fixes: aac426562f56 ("bus: mhi: pci_generic: Introduce Foxconn T99W175 support")
Cc: stable@vger.kernel.org # v5.12+
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Slark Xiao <slark_xiao@163.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20220205135731.157871-2-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-06 13:19:46 +01:00
Thomas Perrot
1dba0075fc bus: mhi: pci_generic: Introduce Sierra EM919X support
Add support for EM919X modems, this modem series is based on SDX55
qcom chip.

It is mandatory to use the same ring for control+data and diag events.

Link: https://lore.kernel.org/r/20211123081541.648426-1-thomas.perrot@bootlin.com
Tested-by: Aleksander Morgado <aleksander@aleksander.es>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Thomas Perrot <thomas.perrot@bootlin.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20211216081227.237749-11-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-17 17:17:15 +01:00
Kees Cook
5a717e9323 bus: mhi: core: Use correctly sized arguments for bit field
The find.h APIs are designed to be used only on unsigned long arguments.
This can technically result in a over-read, but it is harmless in this
case. Regardless, fix it to avoid the warning seen under -Warray-bounds,
which we'd like to enable globally:

In file included from ./include/linux/bitmap.h:9,
                 from ./include/linux/cpumask.h:12,
                 from ./arch/x86/include/asm/cpumask.h:5,
                 from ./arch/x86/include/asm/msr.h:11,
                 from ./arch/x86/include/asm/processor.h:22,
                 from ./arch/x86/include/asm/cpufeature.h:5,
                 from ./arch/x86/include/asm/thread_info.h:53,
                 from ./include/linux/thread_info.h:60,
                 from ./arch/x86/include/asm/preempt.h:7,
                 from ./include/linux/preempt.h:78,
                 from ./include/linux/spinlock.h:55,
                 from ./include/linux/wait.h:9,
                 from ./include/linux/wait_bit.h:8,
                 from ./include/linux/fs.h:6,
                 from ./include/linux/debugfs.h:15,
                 from drivers/bus/mhi/core/init.c:7:
drivers/bus/mhi/core/init.c: In function 'to_mhi_pm_state_str':
./include/linux/find.h:187:37: warning: array subscript 'long unsigned int[0]' is partly outside array bounds of 'enum mhi_pm_state[1]' [-Warray-bounds]
  187 |                 unsigned long val = *addr & GENMASK(size - 1, 0);
      |                                     ^~~~~
drivers/bus/mhi/core/init.c:80:51: note: while referencing 'state'
   80 | const char *to_mhi_pm_state_str(enum mhi_pm_state state)
      |                                 ~~~~~~~~~~~~~~~~~~^~~~~

Link: https://lore.kernel.org/r/20211215232446.2069794-1-keescook@chromium.org
[mani: changed the variable name "bits" to "pm_state"]
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20211216081227.237749-10-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-17 17:17:14 +01:00
Manivannan Sadhasivam
227fee5fc9 bus: mhi: core: Add an API for auto queueing buffers for DL channel
Add a new API "mhi_prepare_for_transfer_autoqueue" for using with client
drivers like QRTR to request MHI core to autoqueue buffers for the DL
channel along with starting both UL and DL channels.

So far, the "auto_queue" flag specified by the controller drivers in
channel definition served this purpose but this will be removed at some
point in future.

Cc: netdev@vger.kernel.org
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Co-developed-by: Loic Poulain <loic.poulain@linaro.org>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20211216081227.237749-9-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-17 17:17:14 +01:00
Manivannan Sadhasivam
d651ce8e91 bus: mhi: core: Fix race while handling SYS_ERR at power up
During SYS_ERR condition, as a response to the MHI_RESET from host, some
devices tend to issue BHI interrupt without clearing the SYS_ERR state in
the device. This creates a race condition and causes a failure in booting
up the device.

The issue is seen on the Sierra Wireless EM9191 modem during SYS_ERR
handling in mhi_async_power_up(). Once the host detects that the device
is in SYS_ERR state, it issues MHI_RESET and waits for the device to
process the reset request. During this time, the device triggers the BHI
interrupt to the host without clearing SYS_ERR condition. So the host
starts handling the SYS_ERR condition again.

To fix this issue, let's register the IRQ handler only after handling the
SYS_ERR check to avoid getting spurious IRQs from the device.

Fixes: e18d4e9fa79b ("bus: mhi: core: Handle syserr during power_up")
Cc: stable@vger.kernel.org
Reported-by: Aleksander Morgado <aleksander@aleksander.es>
Tested-by: Aleksander Morgado <aleksander@aleksander.es>
Tested-by: Thomas Perrot <thomas.perrot@bootlin.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20211216081227.237749-8-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-17 17:17:14 +01:00
Bhaumik Bhatt
42c4668f7e bus: mhi: core: Fix reading wake_capable channel configuration
The 'wake-capable' entry in channel configuration is not set when
parsing the configuration specified by the controller driver. Add
the missing entry to ensure channel is correctly specified as a
'wake-capable' channel.

Link: https://lore.kernel.org/r/1638320491-13382-1-git-send-email-quic_bbhatt@quicinc.com
Fixes: 0cbf260820fa ("bus: mhi: core: Add support for registering MHI controllers")
Cc: stable@vger.kernel.org
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Bhaumik Bhatt <quic_bbhatt@quicinc.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20211216081227.237749-7-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-17 17:17:14 +01:00
Christophe JAILLET
f3d1339736 bus: mhi: pci_generic: Simplify code and axe the use of a deprecated API
The wrappers in include/linux/pci-dma-compat.h should go away.

Replace 'pci_set_dma_mask/pci_set_consistent_dma_mask' by an equivalent
and less verbose 'dma_set_mask_and_coherent()' call.

Link: https://lore.kernel.org/r/bb3dc436fe142309a2334549db782c5ebb80a2be.1625718497.git.christophe.jaillet@wanadoo.fr
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20211216081227.237749-6-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-17 17:17:14 +01:00
Manivannan Sadhasivam
85ec609462 bus: mhi: core: Minor style and comment fixes
This patch fixes the below checkpatch warnings in MHI bus:

WARNING: Possible repeated word: 'events'
+	/* Process ctrl events events */

WARNING: Missing a blank line after declarations
+			struct mhi_buf_info info = { };
+			buf = kmalloc(len, GFP_KERNEL);

WARNING: Move const after static - use 'static const struct mhi_pm_transitions'
+static struct mhi_pm_transitions const dev_state_transitions[] = {

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20211216081227.237749-5-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-17 17:17:14 +01:00
Bhaumik Bhatt
3e60c9f068 bus: mhi: core: Use macros for execution environment features
The implementation for execution environment specific functionality
is spread out. Use macros that help determine the paths to be taken.

Link: https://lore.kernel.org/r/1636409978-31847-1-git-send-email-quic_bbhatt@quicinc.com
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20211216081227.237749-4-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-17 17:17:14 +01:00
Loic Poulain
f77097ec8c bus: mhi: pci_generic: Graceful shutdown on freeze
There is no reason for shutting down MHI ungracefully on freeze,
this causes the MHI host stack & device stack to not be aligned
anymore since the proper MHI reset sequence is not performed for
ungraceful shutdown.

Link: https://lore.kernel.org/r/1635268180-13699-1-git-send-email-loic.poulain@linaro.org
Fixes: 5f0c2ee1fe8d ("bus: mhi: pci-generic: Fix hibernation")
Cc: stable@vger.kernel.org
Suggested-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: Hemant Kumar <hemantk@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20211216081227.237749-3-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-17 17:17:14 +01:00