Some rpmsg backends support holding on to and redelivering messages upon
failed handling of them, so provide a way for the callback to report and
error and allow the backends to handle this.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

Move virtio rpmsg implementation details from the public header file to
the virtio rpmsg implementation.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

Create a container struct virtio_rpmsg_channel around the rpmsg_channel
to keep virtio backend information separate from the rpmsg and public
API. This makes the public structures independant of virtio.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

Extract the generic rpmsg core functionality from the virtio rpmsg
implementation, splitting the implementation in a rpmsg core and a
virtio backend.

Based on initial work by Sricharan R <sricharan@codeaurora.org>

Cc: Sricharan R <sricharan@codeaurora.org>
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

The tail of create_channel() is common among all rpmsg backends, so
split it off from the virtio specific part to allow it to be extracted
to the rpmsg core.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

Extract and move the helper function for finding rpmsg child devices to
the core.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

Move the rpmsg_send() and rpmsg_destroy_ept() interface to the rpmsg
core, so that we eventually can hide the rpmsg_endpoint ops from the
public API.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

Add indirection table for rpmsg_endpoint related operations and move
virtio implementation behind this, this finishes of the decoupling of
the virtio implementation from the public API.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

Extract the now indirect rpmsg_create_ept() interface to a separate
file and start building up a rpmsg core.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

To allow for multiple backend implementations add an indireection table
for rpmsg_device related operations and move the virtio implementation
behind this table.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

The rpmsg device representing struct is called rpmsg_channel and the
variable name used throughout is rpdev, with the communication happening
on endpoints it's clearer to just call this a "device" in a public API.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

As we introduce support for additional rpmsg backends, some of these
only supports point-to-point "links" represented by a name. By making
rpmsg_create_ept() take a channel_info struct we allow for these
backends to either be passed a source address, a destination address or
a name identifier.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

The rpmsg_send() operations has been taking a rpmsg_device, but this
forces users of secondary rpmsg_endpoints to use the rpmsg_sendto()
interface - by extracting source and destination from the given data
structures. If we instead pass the rpmsg_endpoint to these functions a
service can use rpmsg_sendto() to respond to messages, even on secondary
endpoints.

In addition this would allow us to support operations on multiple
channels in future backends that does not support off-channel
operations.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

By basing rpmsg device names on channel id we end up with human readable
device names in sysfs and debug logs.
Reviewed-by: NSarangdhar Joshi <spjoshi@codeaurora.org>
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

Make it possible to match rpmsg devices based on device tree node, in
addition to the id table. In some of these cases the rpmsg driver would
not have a id_table, so make this optional.
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

There are couple of print_hex_dump traces used in rpmsg code which
prints the actual byte messages being transferred between host and
the remote processors. These traces are quiet verbose and affects
performance, if the appropriate trace level is enabled. These hex
dumps are needed rather rarely, but are quite useful when debugging
complex IPC corner cases. So, this patch switches these hex dump
traces to use the dynamic_hex_dump() API.

The hex dump traces are also enabled only when CONFIG_DYNAMIC_DEBUG
is enabled. This switch allows flexibility of controlling these
traces through dynamic debug, instead of removing them completely.
Signed-off-by: NSuman Anna <s-anna@ti.com>
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

This patch fixes most of the existing alignment checkpatch check
warnings of the type "Alignment should match open parenthesis"
in the virtio rpmsg bus code. A couple of them have been left as
is to not exceed the 80-char limit.
Signed-off-by: NSuman Anna <s-anna@ti.com>
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

The dma_addr_t types can be printed properly using the %pad
printk format-specifier, there is no need to resort to the
unsigned long long type-casting to deal with different possible
type sizes.
Signed-off-by: NSuman Anna <s-anna@ti.com>
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

These types of error prints are superfluous. The system will
pick up on OOM issues and let the user know. While at this,
fix the usage of using a structure instead of the actual
variable in one of the allocations.
Signed-off-by: NSuman Anna <s-anna@ti.com>
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

It should never have been there in the first place.
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

Found with scripts/coccinelle/misc/boolconv.cocci.
Signed-off-by: NAndrew F. Davis <afd@ti.com>
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

Add register_rpmsg_driver helper macro that adds THIS_MODULE to
rpmsg_driver for the registering driver. We rename and modify
the existing register_rpmsg_driver to enable this.
Signed-off-by: NAndrew F. Davis <afd@ti.com>
Acked-by: NSuman Anna <s-anna@ti.com>
Signed-off-by: NBjorn Andersson <bjorn.andersson@linaro.org>

checkpatch.pl wants arrays of strings declared as follows:

  static const char * const names[] = { "vq-1", "vq-2", "vq-3" };

Currently the find_vqs() function takes a const char *names[] argument
so passing checkpatch.pl's const char * const names[] results in a
compiler error due to losing the second const.

This patch adjusts the find_vqs() prototype and updates all virtio
transports.  This makes it possible for virtio_balloon.c, virtio_input.c,
virtgpu_kms.c, and virtio_rpmsg_bus.c to use the checkpatch.pl-friendly
type.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NBjorn Andersson <bjorn.andersson@sonymobile.com>

virtio spec requires that all drivers set DRIVER_OK
before using devices. While rpmsg isn't yet
included in the virtio 1 spec, previous spec versions
also required this.

virtio rpmsg violates this rule: is calls kick
before setting DRIVER_OK.

The fix isn't trivial since simply calling virtio_device_ready earlier
would mean we might get an interrupt in parallel with adding buffers.

Instead, split kick out to prepare+notify calls.  prepare before
virtio_device_ready - when we know we won't get interrupts. notify right
afterwards.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NOhad Ben-Cohen <ohad@wizery.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Adjust the number of rpmsg buffers to rely on the size of the
vring, instead of using the hard coded value of 512 (256 per
direction).

This is needed when small vrings are being used, where 256
buffers are too much to fit in a vring.

While considering the vring size, keep using the 512 hard coded
value as an upper limit to avoid wacky resource tables consuming
unreasonable amount of memory.

NOTE: The number of buffers is already assumed to be symmetrical
in each direction, and that logic is unchanged.
Signed-off-by: NSuman Anna <s-anna@ti.com>
[edit commit message, small code and comment simplification]
Signed-off-by: NOhad Ben-Cohen <ohad@wizery.com>

Return a negative error code from the error handling case instead of 0, as
returned elsewhere in this function.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Change virtqueue callback function rpmsg_recv_done() to process all
available messages instead of just one message.
Signed-off-by: NRobert Tivy <rtivy@ti.com>
[split _recv function instead of adding indentation]
Signed-off-by: NOhad Ben-Cohen <ohad@wizery.com>

We never add buffers with input and output parts, so use the new accessors.

Cc: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Convert to the much saner new idr interface.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

idr_destroy() can destroy idr by itself and idr_remove_all() is being
deprecated.  Drop its usage.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Correct spelling typo in printk within various drivers.
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

CONFIG_HOTPLUG is going away as an option.  As a result, the __dev*
markings need to be removed.

This change removes the use of __devinit, __devexit_p, __devinitdata,
__devinitconst, and __devexit from these drivers.

Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.

Cc: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We simplified virtqueue_add_buf(), make it clear in the callers.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

dma_alloc/free_coherent APIs requires the platform specific remoteproc
device as the device parameter. We are passing vdev->dev.parent to the
dma_free_coherent function which is the generic rproc device and it is
wrong, it has to be vdev->dev.parent->parent instead, same as when we
call dma_alloc_coherent function.
Signed-off-by: NFernando Guzman Lugo <fernando.lugo@ti.com>
Signed-off-by: NOhad Ben-Cohen <ohad@wizery.com>

When rpmsg drivers are built into the kernel, they must not initialize
before the rpmsg bus does, otherwise they'd trigger a BUG() in
drivers/base/driver.c line 169 (driver_register()).

To fix that, and to stop depending on arbitrary linkage ordering of
those built-in rpmsg drivers, we make the rpmsg bus initialize at
subsys_initcall.

Cc: stable <stable@vger.kernel.org>
Signed-off-by: NFederico Fuga <fuga@studiofuga.com>
[ohad: rewrite the commit log]
Signed-off-by: NOhad Ben-Cohen <ohad@wizery.com>

For each registered rproc, maintain a generic remoteproc device whose
parent is the low level platform-specific device (commonly a pdev, but
it may certainly be any other type of device too).

With this in hand, the resulting device hierarchy might then look like:

omap-rproc.0
 |
 - remoteproc0  <---- new !
    |
    - virtio0
    |
    - virtio1
       |
       - rpmsg0
       |
       - rpmsg1
       |
       - rpmsg2

Where:
- omap-rproc.0 is the low level device that's bound to the
  driver which invokes rproc_register()
- remoteproc0 is the result of this patch, and will be added by the
  remoteproc framework when rproc_register() is invoked
- virtio0 and virtio1 are vdevs that are registered by remoteproc
  when it realizes that they are supported by the firmware
  of the physical remote processor represented by omap-rproc.0
- rpmsg0, rpmsg1 and rpmsg2 are rpmsg devices that represent rpmsg
  channels, and are registerd by the rpmsg bus when it gets notified
  about their existence

Technically, this patch:
- changes 'struct rproc' to contain this generic remoteproc.x device
- creates a new "remoteproc" type, to which this new generic remoteproc.x
  device belong to.
- adds a super simple enumeration method for the indices of the
  remoteproc.x devices
- updates all dev_* messaging to use the generic remoteproc.x device
  instead of the low level platform-specific device
- updates all dma_* allocations to use the parent of remoteproc.x (where
  the platform-specific memory pools, most commonly CMA, are to be found)

Adding this generic device has several merits:
- we can now add remoteproc runtime PM support simply by hooking onto the
  new "remoteproc" type
- all remoteproc log messages will now carry a common name prefix
  instead of having a platform-specific one
- having a device as part of the rproc struct makes it possible to simplify
  refcounting (see subsequent patch)

Thanks to Stephen Boyd <sboyd@codeaurora.org> for suggesting and
discussing these ideas in one of the remoteproc review threads and
to Fernando Guzman Lugo <fernando.lugo@ti.com> for trying them out
with the (upcoming) runtime PM support for remoteproc.

Cc: Fernando Guzman Lugo <fernando.lugo@ti.com>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NOhad Ben-Cohen <ohad@wizery.com>

When inbound messages arrive, rpmsg core looks up their associated
endpoint (by destination address) and then invokes their callback.

We've made sure that endpoints will never be de-allocated after they
were found by rpmsg core, but we also need to protect against the
(rare) scenario where the rpmsg driver was just removed, and its
callback function isn't available anymore.

This is achieved by introducing a callback mutex, which must be taken
before the callback is invoked, and, obviously, before it is removed.

Cc: stable <stable@vger.kernel.org>
Reported-by: NFernando Guzman Lugo <fernando.lugo@ti.com>
Signed-off-by: NOhad Ben-Cohen <ohad@wizery.com>

When an inbound message arrives, the rpmsg core looks up its
associated endpoint and invokes the registered callback.

If a message arrives while its endpoint is being removed (because
the rpmsg driver was removed, or a recovery of a remote processor
has kicked in) we must ensure atomicity, i.e.:

- Either the ept is removed before it is found

or

- The ept is found but will not be freed until the callback returns

This is achieved by maintaining a per-ept reference count, which,
when drops to zero, will trigger deallocation of the ept.

With this in hand, it is now forbidden to directly deallocate
epts once they have been added to the endpoints idr.

Cc: stable <stable@vger.kernel.org>
Reported-by: NFernando Guzman Lugo <fernando.lugo@ti.com>
Signed-off-by: NOhad Ben-Cohen <ohad@wizery.com>

dev_dbg() in rpmsg_probe() made use of the %x formatting that
expects an 'unsigned int' which dma_addr_t is not in cases where
dma_addr_t is 64-bit (CONFIG_ARCH_DMA_ADDR_T_64BIT). Casting to
a 'unsigned long long' and using %llx will avoid this.
Signed-off-by: NMark Asselstine <mark.asselstine@windriver.com>
CC: Ohad Ben-Cohen <ohad@wizery.com>
CC: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NOhad Ben-Cohen <ohad@wizery.com>

After processing an incoming message, always publish the real size
of its containing buffer when putting it back on the available rx ring.

Using any different value might erroneously limit the remote processor
(leading it to think the buffer is smaller than it really is).
Signed-off-by: NOhad Ben-Cohen <ohad@wizery.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Mark Grosen <mgrosen@ti.com>
Cc: Suman Anna <s-anna@ti.com>
Cc: Fernando Guzman Lugo <fernando.lugo@ti.com>
Cc: Rob Clark <rob@ti.com>
Cc: Ludovic BARRE <ludovic.barre@stericsson.com>
Cc: Loic PALLARDY <loic.pallardy@stericsson.com>
Cc: Omar Ramirez Luna <omar.luna@linaro.org>