There are times, such as when the modem crashes, when we issue
commands to clear the IPA hardware pipeline. These commands include
a data transfer command that delivers a small packet directly to the
default (AP<-LAN RX) endpoint.
The places that do this wait for the transactions that contain these
commands to complete, but the pipeline can't be assumed clear until
the sent packet has been *received*.
The small transfer will be delivered with a status structure, and
that status will indicate its tag is valid. This is the only place
we send a tagged packet, so we use the tag to determine when the
pipeline clear packet has arrived.
Add a completion to the IPA structure to to be used to signal
the receipt of a pipeline clear packet. Create a new function
ipa_cmd_pipeline_clear_wait() that will wait for that completion.
Reinitialize the completion whenever pipeline clear commands are
added to a transaction. Extend ipa_endpoint_status_tag() to check
whether a packet whose status contains a valid tag was sent from the
AP->command TX endpoint, and if so, signal the new IPA completion.
Have all callers of ipa_cmd_pipeline_clear_add() wait for the
pipeline clear indication after the transaction that clears the
pipeline has completed.
Signed-off-by: Alex Elder <elder@linaro.org>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The IPA driver currently requires a DT property to be defined whose
value is the phandle for the modem subsystem. This was needed to
look up a remoteproc structure pointer used when registering for
notifications in the original IPA notification mechanism.
Remoteproc provides a more generic SSR notifier system, and the IPA
driver switched over to it last summer, but this remoteproc phandle
dependency was not removed at that time.
Get rid of the IPA remoteproc pointer and stop requiring the phandle
be specified.
This avoids a link error (rproc_put() not defined) for certain
configurations.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The previous patch causes a system resume to be triggered when a
packet is available for receipt on a suspended RX endpoint.
The CLOCK_HELD flag was previously used to indicate that an extra
clock reference was held, preventing suspend. But we no longer need
such a flag:
- We take an initial reference in ipa_config().
- That reference is held until ipa_suspend() releases it.
- A subsequent system resume leads to a reference getting
re-acquired in ipa_resume().
- This can repeat until ultimately the module is removed, where
ipa_remove() releases the reference.
We no longer need a special flag to determine whether this extra
reference is held--it is, provided probe has completed successfully
and the driver is not suspended (or removed).
On the other hand, once suspended, it's possible for more than one
endpoint to trip the IPA SUSPEND interrupt, and we only want to
trigger the system resume once. So repurpose the Boolean CLOCK_HELD
flag to record whether the IPA SUSPEND handler should initiate a
system resume.
The flag will be be cleared each time ipa_suspend() is called,
*before* any endpoints are suspended. And it will be set inside the
IPA SUSPEND interrupt handler exactly once per suspend.
Rename the flag IPA_FLAG_RESUMED to reflect its new purpose.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The call to wakeup_source_register() in ipa_probe() does not do what
it was intended to do. Call device_init_wakeup() in ipa_setup()
instead, to set the IPA device as wakeup-capable and to initially
enable wakeup capability.
When we receive a SUSPEND interrupt, call pm_wakeup_dev_event()
with a zero processing time, to simply call for a resume without
any other processing. The ipa_resume() call will take care of
waking things up again, and will handle receiving the packet.
Note that this gets rid of a clock reference counting bug that
occurred when handling an IPA SUSPEND interrupt. Specifically,
ipa_suspend_handler() took an IPA clock reference *in addition*
to the one taken by ipa_resume(). There is no need to back-port
this fix however, because it only affects code that was not
previously working (this patch is part of fixing that).
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We take a clock reference in ipa_config() in order to prevent the
the IPA clock from being shutdown until a power management suspend
request arrives. An atomic field in the IPA structure records
whether that extra reference had been taken.
Rather than using an atomic to represent a Boolean value, define
a new flags bitmap, and define a "clock held" flag to represent
whether the extra clock reference has been taken.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove linux/notifier.h which is included more than once
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai38@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the new SSR notifier infrastructure to request notifications of
modem events, rather than the remoteproc IPA notification system.
The latter was put in place temporarily with the knowledge that the
new mechanism would become available.
Acked-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Alex Elder <elder@linaro.org>
Link: https://lore.kernel.org/r/20200724181142.13581-2-elder@linaro.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Arrange to use an item from SMEM memory for IPA. SMEM item number
497 is designated to be used by the IPA. Specify the item ID and
size of the region in platform configuration data. Allocate and get
a pointer to this region from ipa_mem_init(). The memory must be
mapped for access through an SMMU.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Define a region of IMEM memory available for use by IPA in the
platform configuration data. Initialize it from ipa_mem_init().
The memory must be mapped for access through an SMMU.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch includes three source files that represent some basic "main
program" code for the IPA driver. They are:
- "ipa.h" defines the top-level IPA structure which represents an IPA
device throughout the code.
- "ipa_main.c" contains the platform driver probe function, along with
some general code used during initialization.
- "ipa_reg.h" defines the offsets of the 32-bit registers used for the
IPA device, along with masks that define the position and width of
fields within these registers.
- "version.h" defines some symbolic IPA version numbers.
Each file includes some documentation that provides a little more
overview of how the code is organized and used.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alex Elder