Граф коммитов

23 Коммитов

Автор SHA1 Сообщение Дата
Linus Torvalds 3e11a00d85 A small pull request consisting of:
- Make rpmsg process all pending messages instead of just
   one, from Robert Tivy
 - Fix Kconfig dependency on VIRTUALIZATION, from Suman.
   Note: this was submitted late during the 3.9 rc cycle and it
   seemed appropriate to wait with it for the merge window.
 - Belated addition of an rpmsg entry to the MAINTAINERS file.
   People seem to look for this.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.11 (GNU/Linux)
 
 iQIcBAABAgAGBQJRiOZyAAoJELLolMlTRIoM7ToQAIsuq4S/YWfvZGDmHg7wsyGn
 DTtTEGo61mE+B0yJ0+fGw/b1LLjFrai9Ugr5zKyntwNWjuVJwtAtfvGcjoOSs3pK
 CJcpAADp+y92Dl5/6iLZwwQSMb2/OD0dfltTyvehoj4GOyVTmXZRwqLcsClZUYL3
 ISrxNaRKoEGyyGSUSRG2B6g1YvuoY39UFmFOXAMHitT0Oq2rgZR/RzFXmk/FUsPy
 sTxmevaLuN65RufqO2qAprdIZDk4TZf+2YC2BAEdHHiuFhykZukUxLCRH9L4DLhw
 j+EHWH8vLrfLCHb1FFR6Qj3R0mMsHiYHvfsdHIbRZGB9iJfszEMi53otGUdY3EF8
 bj7aAv/aI71Mg+OC98TWcCCRzdFowjfMKVTSpDwp6hNj0MrYGbmrmuqpDPiq+cmo
 axeUJWeytMEI/N1Lh+uJBMUa3Qa5j++iPur/vw2EZj/KWqGFTFACKagUp7fMT8QD
 7qlQF/6Dfmh5WzI5U7RrryaP6h/hKAFNIzNoiQRGFl+eybLULm+/6NluTPQunNbo
 7EgBpS+5ktpGu6fbDr8z+CUYrV4b6wXNinj7qjnGOwYJlQiyNaRtM3cuL34ZIP3q
 g2p23stIkjOlCkDt25SOBz6vrLTPzybxCaL8ipSl3HAOXDAKxT+055IhAYeYCJQ1
 op1V1BIAw6TTxhvL3del
 =dDx5
 -----END PGP SIGNATURE-----

Merge tag 'rpmsg-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/rpmsg

Pull rpmsg changes from Ohad Ben-Cohen:
 "A small pull request consisting of:

   - Make rpmsg process all pending messages instead of just one, from
     Robert Tivy

   - Fix Kconfig dependency on VIRTUALIZATION, from Suman.

     Note: this was submitted late during the 3.9 rc cycle and it seemed
     appropriate to wait with it for the merge window.

   - Belated addition of an rpmsg entry to the MAINTAINERS file.  People
     seem to look for this"

* tag 'rpmsg-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/rpmsg:
  rpmsg: fix kconfig dependencies for VIRTIO
  MAINTAINERS: add rpmsg entry
  rpmsg: process _all_ pending messages in rpmsg_recv_done
2013-05-07 14:02:00 -07:00
Linus Torvalds 736a2dd257 Lots of virtio work which wasn't quite ready for last merge window. Plus
I dived into lguest again, reworking the pagetable code so we can move
 the switcher page: our fixmaps sometimes take more than 2MB now...
 
 Cheers,
 Rusty.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.12 (GNU/Linux)
 
 iQIcBAABAgAGBQJRga7lAAoJENkgDmzRrbjx/yIQAKpqIBtxOJeYH3SY+Uoe7Cfp
 toNYcpJEldvb0UcWN8M2cSZpHoxl1SUoq9djwcM29tcKa7EZAjHaGtb/Q1qMTDgv
 +B3WAfiGU2pmXFxLAkbrlLNGnysy24JspqJQ5hcYV84EiBxQdZp+nCYgOphd+GMK
 ww16vo9ya8jFjzt3GeRp/Heb3vEzV4Cp6BC3i0m8A3WNpEpbRb66pqXNk5o8ggJO
 SxQOKSXmUM+0m+jKSul5xn3e2Ls2LOrZZ8/DIHA+gW66N4Zab7n2/j1Q9VRxb4lh
 FqnR7KwgBX8OCh9IsBDqQYS7MohvMYge6eUdLtFrq84jvMleMEhrC8q9v2tucFUb
 5t18CLwvyK7Gdg6UCKiZ7YSPcuURAILO16al9bh5IseeBDsuX+43VsvQoBmFn9k6
 cLOVTZ6BlOmahK5PyRYFSvLa9Rxzr/05Mr7oYq9UgshD9io78dnqczFYIORF53rW
 zD7C4HuTZfYJFfNd0wAJ0RfVXnf8QvDlMdo7zPC26DSXNWqj8OexCY0qqSWUB+2F
 vcfJP6NkV4fZB8aawWIFUVwc64yqtt2uPVLa7ATZWqk16PgKrchGewmw3tiEwOgu
 1l7xgffTRRUIJsqaCZoXdgw3yezcKRjuUBcOxL09lDAAhc+NxWNvzZBsKp66DwDk
 yZQKn0OdXnuf0CeEOfFf
 =1tYL
 -----END PGP SIGNATURE-----

Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull virtio & lguest updates from Rusty Russell:
 "Lots of virtio work which wasn't quite ready for last merge window.

  Plus I dived into lguest again, reworking the pagetable code so we can
  move the switcher page: our fixmaps sometimes take more than 2MB now..."

Ugh.  Annoying conflicts with the tcm_vhost -> vhost_scsi rename.
Hopefully correctly resolved.

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (57 commits)
  caif_virtio: Remove bouncing email addresses
  lguest: improve code readability in lg_cpu_start.
  virtio-net: fill only rx queues which are being used
  lguest: map Switcher below fixmap.
  lguest: cache last cpu we ran on.
  lguest: map Switcher text whenever we allocate a new pagetable.
  lguest: don't share Switcher PTE pages between guests.
  lguest: expost switcher_pages array (as lg_switcher_pages).
  lguest: extract shadow PTE walking / allocating.
  lguest: make check_gpte et. al return bool.
  lguest: assume Switcher text is a single page.
  lguest: rename switcher_page to switcher_pages.
  lguest: remove RESERVE_MEM constant.
  lguest: check vaddr not pgd for Switcher protection.
  lguest: prepare to make SWITCHER_ADDR a variable.
  virtio: console: replace EMFILE with EBUSY for already-open port
  virtio-scsi: reset virtqueue affinity when doing cpu hotplug
  virtio-scsi: introduce multiqueue support
  virtio-scsi: push vq lock/unlock into virtscsi_vq_done
  virtio-scsi: pass struct virtio_scsi to virtqueue completion function
  ...
2013-05-02 14:14:04 -07:00
Wei Yongjun 3119b487e0 drivers/rpmsg/virtio_rpmsg_bus.c: fix error return code in rpmsg_probe()
Return a negative error code from the error handling case instead of 0, as
returned elsewhere in this function.

Signed-off-by: Wei 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 18:28:13 -07:00
Robert Tivy 1aa7d6a5d0 rpmsg: process _all_ pending messages in rpmsg_recv_done
Change virtqueue callback function rpmsg_recv_done() to process all
available messages instead of just one message.

Signed-off-by: Robert Tivy <rtivy@ti.com>
[split _recv function instead of adding indentation]
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
2013-04-15 09:14:09 +03:00
Rusty Russell cee51d69a4 virtio_rpmsg_bus: use simplified virtqueue accessors.
We never add buffers with input and output parts, so use the new accessors.

Cc: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-03-20 15:45:05 +10:30
Tejun Heo d0ffce779d rpmsg: convert to idr_alloc()
Convert to the much saner new idr interface.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:18 -08:00
Tejun Heo a15abcc961 rpmsg: don't use idr_remove_all()
idr_destroy() can destroy idr by itself and idr_remove_all() is being
deprecated.  Drop its usage.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ohad Ben-Cohen <ohad@wizery.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:13 -08:00
Jiri Kosina 617677295b Merge branch 'master' into for-next
Conflicts:
	drivers/devfreq/exynos4_bus.c

Sync with Linus' tree to be able to apply patches that are
against newer code (mvneta).
2013-01-29 10:48:30 +01:00
Masanari Iida 8a168ca707 treewide: Fix typo in various drivers
Correct spelling typo in printk within various drivers.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-01-09 11:43:32 +01:00
Greg Kroah-Hartman 0fe763c570 Drivers: misc: remove __dev* attributes.
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-03 15:57:16 -08:00
Rusty Russell 57e1a37347 virtio: rpmsg: make it clear that virtqueue_add_buf() no longer returns > 0
We simplified virtqueue_add_buf(), make it clear in the callers.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-12-18 15:20:36 +10:30
Fernando Guzman Lugo eeb0074f36 rpmsg: fix dma_free_coherent dev parameter
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: Fernando Guzman Lugo <fernando.lugo@ti.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
2012-09-12 12:03:57 +03:00
Linus Torvalds a9197f903f A batch of remoteproc patches for 3.6:
- custom binary format support from Sjur Brændeland
 - groundwork for recovery and runtime pm support
 - some cleanups and API simplifications
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.11 (GNU/Linux)
 
 iQIcBAABAgAGBQJQD75aAAoJELLolMlTRIoMM84P/RfnGhFl/mzKmDssFtwkajIb
 HRrZ1/YWjAjnSOvD5FF+LrS4TtxPgx9747I1Xh49Uk7DHb6siNTDUNbFJNifWo7g
 TbKo3LgLllfNXnwbunIfiGqOW2HzaCVo6vhk59fL3QAsdtCDlROegt1NbOrV8T2S
 +XZlgYhhUSlIQQCgsRBVJWbwP4k5PtAYmwL1VN7ONgj2ILJDP7MhAasDMl+KeGSG
 128g+aCoIkfc9vC+ghDNAfE6DsHHeVyXAWPoWHoyjiteZ1NDkGxUBdTbsrtMYM2K
 ZguEISfVNcMSk10HhoYWtqYZfZUTEM18kOt/182CEwpRVRE34Z7fhcQCiCGX6u6v
 E+7tNj/0qow+dcj2OtS3NEePIHKcuvjBQ09b6GED+qsmC8lENo2Ly364T6JfriNl
 tv1PShvmodrBlLFusAikJKuzYFI9xgQawpL3oV0pMrEiujHqgNhuqrCQJkIWnA8d
 9At2RZAMdFBFa7gd90lPicVqPR9HcGipVk7bKRyFAoqmpPLI85Nm1r9l4TPqEXpC
 Otb373gX30yqWNRD9Hmmxx/+40S2odELEDN4wrPRF+cCAbmWtFey415gdoaqBESn
 BiTRrHxNy2+dKsCgSUQMyn59rF552qrCb31REYAyMMImpftAaWP35OREFNn6oqj2
 vzxsc4wcWZaLflrqQGj6
 =vBgg
 -----END PGP SIGNATURE-----

Merge tag 'remoteproc-for-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/remoteproc

Pull remoteproc update from Ohad Ben-Cohen:
 - custom binary format support from Sjur Brændeland
 - groundwork for recovery and runtime pm support
 - some cleanups and API simplifications

Fix up conflicts in drivers/remoteproc/remoteproc_core.c due to clashes
with earlier cleanups by Sjur Brændeland (with part of the cleanups
moved into the new remoteproc_elf_loader.c file).

* tag 'remoteproc-for-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/remoteproc:
  MAINTAINERS: add remoteproc's git
  remoteproc: Support custom firmware handlers
  remoteproc: Move Elf related functions to separate file
  remoteproc: Add function rproc_get_boot_addr
  remoteproc: Pass struct fw to load_segments and find_rsc_table.
  remoteproc: adopt the driver core's alloc/add/del/put naming
  remoteproc: remove the get_by_name/put API
  remoteproc: support non-iommu carveout assignment
  remoteproc: simplify unregister/free interfaces
  remoteproc: remove the now-redundant kref
  remoteproc: maintain a generic child device for each rproc
  remoteproc: allocate vrings on demand, free when not needed
2012-07-26 16:19:08 -07:00
Federico Fuga 9634252617 rpmsg: fix dependency on initialization order
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: Federico Fuga <fuga@studiofuga.com>
[ohad: rewrite the commit log]
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
2012-07-17 13:10:38 +03:00
Ohad Ben-Cohen b5ab5e24e9 remoteproc: maintain a generic child device for each rproc
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: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
2012-07-06 00:53:03 +03:00
Ohad Ben-Cohen 15fd943af5 rpmsg: make sure inflight messages don't invoke just-removed callbacks
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: Fernando Guzman Lugo <fernando.lugo@ti.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
2012-07-04 11:51:59 +03:00
Ohad Ben-Cohen 5a081caa04 rpmsg: avoid premature deallocation of endpoints
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: Fernando Guzman Lugo <fernando.lugo@ti.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
2012-07-04 11:51:42 +03:00
Mark Asselstine 9d8ae5c22b rpmsg: fix build warning when dma_addr_t is 64-bit
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: Mark Asselstine <mark.asselstine@windriver.com>
CC: Ohad Ben-Cohen <ohad@wizery.com>
CC: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
2012-03-04 13:43:41 +02:00
Ohad Ben-Cohen f1d9e9c767 rpmsg: fix published buffer length in rpmsg_recv_done
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: Ohad 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>
2012-02-28 19:10:04 +02:00
Ohad Ben-Cohen 9648224e56 rpmsg: validate incoming message length before propagating
When an inbound message arrives, validate its reported length before
propagating it, otherwise buggy (or malicious) remote processors might
trick us into accessing memory which we really shouldn't.

Signed-off-by: Ohad 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>
2012-02-28 19:10:04 +02:00
Ohad Ben-Cohen fa2d7795b2 rpmsg: fix name service endpoint leak
The name service endpoint wasn't destroyed, so fix it.

This is achieved by introducing an internal __rpmsg_destroy_ept
function which doesn't assume the given ept is bound to an rpmsg
channel (much like the existing __rpmsg_create_ept).

This is needed because the name service ept belongs to the rpmsg bus,
and is never bound with a specific rpdev.

Reported-by: Omar Ramirez Luna <omar.ramirez@ti.com>
Signed-off-by: Ohad 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.ramirez@ti.com>
2012-02-28 19:09:54 +02:00
Axel Lin b719587eb4 rpmsg: rename virtqueue_add_buf_gfp to virtqueue_add_buf
Since commit 7bb7aef2 "virtio: rename virtqueue_add_buf_gfp to virtqueue_add_buf",
virtqueue_add_buf_gfp is already rename to virtqueue_add_buf now.

This patch fixes below build error:
 CC [M]  drivers/rpmsg/virtio_rpmsg_bus.o
drivers/rpmsg/virtio_rpmsg_bus.c: In function 'rpmsg_send_offchannel_raw':
drivers/rpmsg/virtio_rpmsg_bus.c:723: error: implicit declaration of function 'virtqueue_add_buf_gfp'
make[2]: *** [drivers/rpmsg/virtio_rpmsg_bus.o] Error 1
make[1]: *** [drivers/rpmsg] Error 2
make: *** [drivers] Error 2

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
2012-02-22 18:28:48 +02:00
Ohad Ben-Cohen bcabbccabf rpmsg: add virtio-based remote processor messaging bus
Add a virtio-based inter-processor communication bus, which enables
kernel drivers to communicate with entities, running on remote
processors, over shared memory using a simple messaging protocol.

Every pair of AMP processors share two vrings, which are used to send
and receive the messages over shared memory.

The header of every message sent on the rpmsg bus contains src and dst
addresses, which make it possible to multiplex several rpmsg channels on
the same vring.

Every rpmsg channel is a device on this bus. When a channel is added,
and an appropriate rpmsg driver is found and probed, it is also assigned
a local rpmsg address, which is then bound to the driver's callback.

When inbound messages carry the local address of a bound driver,
its callback is invoked by the bus.

This patch provides a kernel interface only; user space interfaces
will be later exposed by kernel users of this rpmsg bus.

Designed with Brian Swetland <swetland@google.com>.

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au> (virtio_ids.h)
Cc: Brian Swetland <swetland@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg KH <greg@kroah.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
2012-02-08 22:53:58 +02:00