net: wwan: t7xx: Infrastructure for early port configuration

To support cases such as FW update or Core dump, the t7xx
device is capable of signaling the host that a special port
needs to be created before the handshake phase.

Adds the infrastructure required to create the early ports
which also requires a different configuration of CLDMA queues.

Base on the v5 patch version of follow series:
'net: wwan: t7xx: fw flashing & coredump support'
(https://patchwork.kernel.org/project/netdevbpf/patch/3777bb382f4b0395cb594a602c5c79dbab86c9e0.1674307425.git.m.chetan.kumar@linux.intel.com/)

Signed-off-by: Jinjian Song <jinjian.song@fibocom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: wwan: t7xx: Add AP CLDMA

At this moment with the current status, t7xx is not functional due to
problems like this after connection, if there is no activity:
[ 57.370534] mtk_t7xx 0000:72:00.0: [PM] SAP suspend error: -110
[ 57.370581] mtk_t7xx 0000:72:00.0: can't suspend
(t7xx_pci_pm_runtime_suspend [mtk_t7xx] returned -110)
because after this, the traffic no longer works.

The complete series 'net: wwan: t7xx: fw flashing & coredump support'
was reverted because of issues with the pci implementation.
In order to have at least the modem working, it would be enough if just
the first commit of the series is re-applied:
d20ef656f994 net: wwan: t7xx: Add AP CLDMA
With that, the Application Processor would be controlled, correctly
suspended and the commented problems would be fixed (I am testing here
like this with no related issue).

This commit is independent of the others and not related to the
commented pci implementation for the new features: fw flashing and
coredump collection.

Use v2 patch version of d20ef656f994 as JinJian Song suggests
(https://patchwork.kernel.org/project/netdevbpf/patch/20230105154215.198828-1-m.chetan.kumar@linux.intel.com/).

Original text from the commit that would be re-applied:

d20ef656f994 net: wwan: t7xx: Add AP CLDMA
Author: Haijun Liu <haijun.liu@mediatek.com>
Date: Tue Aug 16 09:53:28 2022 +0530

The t7xx device contains two Cross Layer DMA (CLDMA) interfaces to
communicate with AP and Modem processors respectively. So far only
MD-CLDMA was being used, this patch enables AP-CLDMA.

Rename small Application Processor (sAP) to AP.

Signed-off-by: Haijun Liu <haijun.liu@mediatek.com>
Co-developed-by: Madhusmita Sahu <madhusmita.sahu@intel.com>
Signed-off-by: Madhusmita Sahu <madhusmita.sahu@intel.com>
Signed-off-by: Moises Veleta <moises.veleta@linux.intel.com>
Signed-off-by: Devegowda Chandrashekar <chandrashekar.devegowda@intel.com>
Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>

Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/20230711062817.6108-1-jtornosm@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Revert "Merge branch 'wwan-t7xx-fw-flashing-and-coredump-support'"

This reverts commit 5417197dd516a8e115aa69f62a7b7554b0c3829c, reversing
changes made to 0630f64d25a0f0a8c6a9ce9fde8750b3b561e6f5.

Reverting to allow addressing review comments.

Link: https://lore.kernel.org/all/4c5dbea0-52a9-1c3d-7547-00ea54c90550@linux.intel.com/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: wwan: t7xx: Enable devlink based fw flashing and coredump collection

This patch brings-in support for t7xx wwan device firmware flashing &
coredump collection using devlink.

Driver Registers with Devlink framework.
Implements devlink ops flash_update callback that programs modem firmware.
Creates region & snapshot required for device coredump log collection.
On early detection of wwan device in fastboot mode driver sets up CLDMA0 HW
tx/rx queues for raw data transfer then registers with devlink framework.
Upon receiving firmware image & partition details driver sends fastboot
commands for flashing the firmware.

In this flow the fastboot command & response gets exchanged between driver
and device. Once firmware flashing is success completion status is reported
to user space application.

Below is the devlink command usage for firmware flashing

$devlink dev flash pci/$BDF file ABC.img component ABC

Note: ABC.img is the firmware to be programmed to "ABC" partition.

In case of coredump collection when wwan device encounters an exception
it reboots & stays in fastboot mode for coredump collection by host driver.
On detecting exception state driver collects the core dump, creates the
devlink region & reports an event to user space application for dump
collection. The user space application invokes devlink region read command
for dump collection.

Below are the devlink commands used for coredump collection.

devlink region new pci/$BDF/mr_dump
devlink region read pci/$BDF/mr_dump snapshot $ID address $ADD length $LEN
devlink region del pci/$BDF/mr_dump snapshot $ID

Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
Signed-off-by: Devegowda Chandrashekar <chandrashekar.devegowda@intel.com>
Signed-off-by: Mishra Soumya Prakash <soumya.prakash.mishra@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: wwan: t7xx: Infrastructure for early port configuration

To support cases such as FW update or Core dump, the t7xx device
is capable of signaling the host that a special port needs
to be created before the handshake phase.

This patch adds the infrastructure required to create the
early ports which also requires a different configuration of
CLDMA queues.

Signed-off-by: Haijun Liu <haijun.liu@mediatek.com>
Co-developed-by: Madhusmita Sahu <madhusmita.sahu@intel.com>
Signed-off-by: Madhusmita Sahu <madhusmita.sahu@intel.com>
Signed-off-by: Ricardo Martinez <ricardo.martinez@linux.intel.com>
Signed-off-by: Devegowda Chandrashekar <chandrashekar.devegowda@intel.com>
Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: wwan: t7xx: Add AP CLDMA

The t7xx device contains two Cross Layer DMA (CLDMA) interfaces to
communicate with AP and Modem processors respectively. So far only
MD-CLDMA was being used, this patch enables AP-CLDMA.

Rename small Application Processor (sAP) to AP.

Signed-off-by: Haijun Liu <haijun.liu@mediatek.com>
Co-developed-by: Madhusmita Sahu <madhusmita.sahu@intel.com>
Signed-off-by: Madhusmita Sahu <madhusmita.sahu@intel.com>
Signed-off-by: Moises Veleta <moises.veleta@linux.intel.com>
Signed-off-by: Devegowda Chandrashekar <chandrashekar.devegowda@intel.com>
Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: wwan: t7xx: Data path HW layer

Data Path Modem AP Interface (DPMAIF) HW layer provides HW abstraction
for the upper layer (DPMAIF HIF). It implements functions to do the HW
configuration, TX/RX control and interrupt handling.

Signed-off-by: Haijun Liu <haijun.liu@mediatek.com>
Signed-off-by: Chandrashekar Devegowda <chandrashekar.devegowda@intel.com>
Co-developed-by: Ricardo Martinez <ricardo.martinez@linux.intel.com>
Signed-off-by: Ricardo Martinez <ricardo.martinez@linux.intel.com>
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: wwan: t7xx: Add core components

Registers the t7xx device driver with the kernel. Setup all the core
components: PCIe layer, Modem Host Cross Core Interface (MHCCIF),
modem control operations, modem state machine, and build
infrastructure.

* PCIe layer code implements driver probe and removal.
* MHCCIF provides interrupt channels to communicate events
such as handshake, PM and port enumeration.
* Modem control implements the entry point for modem init,
reset and exit.
* The modem status monitor is a state machine used by modem control
to complete initialization and stop. It is used also to propagate
exception events reported by other components.

Signed-off-by: Haijun Liu <haijun.liu@mediatek.com>
Signed-off-by: Chandrashekar Devegowda <chandrashekar.devegowda@intel.com>
Co-developed-by: Ricardo Martinez <ricardo.martinez@linux.intel.com>
Signed-off-by: Ricardo Martinez <ricardo.martinez@linux.intel.com>
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: wwan: t7xx: Add control DMA interface

Cross Layer DMA (CLDMA) Hardware interface (HIF) enables the control
path of Host-Modem data transfers. CLDMA HIF layer provides a common
interface to the Port Layer.

CLDMA manages 8 independent RX/TX physical channels with data flow
control in HW queues. CLDMA uses ring buffers of General Packet
Descriptors (GPD) for TX/RX. GPDs can represent multiple or single
data buffers (DB).

CLDMA HIF initializes GPD rings, registers ISR handlers for CLDMA
interrupts, and initializes CLDMA HW registers.

CLDMA TX flow:
1. Port Layer write
2. Get DB address
3. Configure GPD
4. Triggering processing via HW register write

CLDMA RX flow:
1. CLDMA HW sends a RX "done" to host
2. Driver starts thread to safely read GPD
3. DB is sent to Port layer
4. Create a new buffer for GPD ring

Note: This patch does not enable compilation since it has dependencies
such as t7xx_pcie_mac_clear_int()/t7xx_pcie_mac_set_int() and
struct t7xx_pci_dev which are added by the core patch.

Signed-off-by: Haijun Liu <haijun.liu@mediatek.com>
Signed-off-by: Chandrashekar Devegowda <chandrashekar.devegowda@intel.com>
Co-developed-by: Ricardo Martinez <ricardo.martinez@linux.intel.com>
Signed-off-by: Ricardo Martinez <ricardo.martinez@linux.intel.com>
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>