The existing code uses one pair of interrupt handler/thread per link
but at the hardware level the interrupt is shared. This works fine for
legacy PCI interrupts, but leads to timeouts in MSI (Message-Signaled
Interrupt) mode, likely due to edges being lost.
This patch unifies interrupt handling for all links. The dedicated
handler is removed since we use a common one for all shared interrupt
sources, and the thread function takes care of dealing with interrupt
sources. This partition follows the model used for the SOF IPC on
HDaudio platforms, where similar timeout issues were noticed and doing
all the interrupt handling/clearing in the thread improved
reliability/stability.
Validation results with 4 links active in parallel show a night-and-day
improvement with no timeouts noticed even during stress tests. Latency
and quality of service are not affected by the change - mostly because
events on a SoundWire link are throttled by the bus frame rate
(typically 8..48kHz).
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200716150947.22119-8-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Somehow the existing code is not aligned with the steps described in
the documentation, refactor code and make sure the register
programming sequences are correct. Also add missing power-up,
power-down and wake capabilities (the last two are used in follow-up
patches but introduced here for consistency).
Some of the SHIM registers exposed fields that are link specific, and
in addition some of the power-related registers (SPA/CPA) take time to
be updated. Uncontrolled access leads to timeouts or errors. Add a
mutex, shared by all links, so that all accesses to such registers are
serialized, and follow a pattern of read-modify-write.
This includes making sure SHIM_SYNC is programmed only once, before
the first master is powered on. We use a 'shim_mask' field, shared
between all links and protected by a mutex, to deal with power-up and
power-down sequences.
Note that the SYNCPRD value is tied only to the XTAL value and not the
current bus frequency or the frame rate.
BugLink: https://github.com/thesofproject/linux/issues/1555
Signed-off-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200716150947.22119-3-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Rather than a plain-vanilla init/exit, this patch provides 3 steps in
the initialization needed for driver selection, machine driver
selection and deal with power rail dependencies.
- ACPI scan: this step is done at a very early stage to detect the
presence of a SoundWire Controller and enabled links at the BIOS
level. This step may be called from the legacy HDaudio driver, which
will abort its probe to let the Sound Open Firmware (SOF) handle the
hardware.
- probe: this step allocates all the required memory and will add a
sdw_bus, which in turn will result in identifying all possible Slaves
listed below the Controller ACPI companion device. All the information
is reported to the parent PCI driver which will select the relevant
machine driver.
- startup: this last step starts the bus reset, which results in Slave
devices reporting as ATTACHED and being enumerated. This step is only
done during the card creation stage, after the DSP is powered to
account for internal power rail dependencies.
These 3 steps are already supported in the Sound Open firmware
drivers and upstream.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200531182102.27840-7-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The code can be simplified a bit to have a more consistent use of
'dev' and 'bus', as well as move definitions around. This will help
make the major changes in follow-up patches easier to review.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200531182102.27840-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The SoundWire DAIs for Intel platform are created in
drivers/soundwire/intel.c, while the communication with the Intel DSP
is all controlled in soc/sof/intel
When the DAI status changes, a callback is used to bridge the gap
between the two subsystems.
The naming of the existing 'config_stream' callback does not map well
with any of ALSA/ASoC concepts. This patch renames it as
'params_stream' to be more self-explanatory.
A new 'free_stream' callback is added in case any resources allocated
in the 'params_stream' stage need to be released. In the SOF
implementation, this is used in the hw_free case to release the DMA
channels over IPC.
These two callbacks now rely on structures which expose the link_id
and alh_stream_id (required by the firmware IPC), instead of a list of
parameters. The 'void *' definitions are changed to use explicit
types, as suggested on alsa-devel during earlier reviews.
Signed-off-by: Rander Wang <rander.wang@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191212014507.28050-7-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The current interfaces between ASoC and SoundWire are limited by the
platform_device infrastructure to an init() and exit() (mapped to the
platform driver.probe and .remove)
To help with the platform detection, machine driver selection and
management of power dependencies between DSP and SoundWire IP, the
ASoC side requires:
a) an ACPI scan helper, to report if any devices are exposed in the
DSDT tables, and if any links are disabled by the BIOS.
b) a probe helper that allocates the resources without actually
starting the bus.
c) a startup helper which does start the bus when all power
dependencies are settled.
d) an exit helper to free all resources
e) an interrupt_enable/disable helper, typically invoked after the
startup helper but also used in suspend routines.
This patch moves all required interfaces to sdw_intel.h, mainly to
allow SoundWire and ASoC parts to be merged separately once the header
files are shared between trees.
To avoid compilation issues, the conflicts in intel_init.c are blindly
removed. This would in theory prevent the code from working, but since
there are no users of the Intel Soundwire driver this has no
impact. Functionality will be restored when the removal of platform
devices is complete.
Support for SoundWire + SOF builds will only be provided once all the
required pieces are upstream.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191212014507.28050-6-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Add DAI registration and DAI ops for the Intel driver along with
callback for topology configuration.
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Signed-off-by: Shreyas NC <shreyas.nc@intel.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
