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2012-03-06remoteproc: remove the single rpmsg vdev limitationOhad Ben-Cohen
Now that the resource table supports publishing a virtio device in a single resource entry, firmware images can start supporting more than a single vdev. This patch removes the single vdev limitation of the remoteproc framework so multi-vdev firmwares can be leveraged: VDEV resource entries are parsed when the rproc is registered, and as a result their vrings are set up and the virtio devices are registered (and they go away when the rproc goes away). Moreover, we no longer only support VIRTIO_ID_RPMSG vdevs; any virtio device type goes now. As a result, there's no more any rpmsg-specific APIs or code in remoteproc: it all becomes generic virtio handling. Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com> Cc: Brian Swetland <swetland@google.com> Cc: Iliyan Malchev <malchev@google.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Mark Grosen <mgrosen@ti.com> Cc: John Williams <john.williams@petalogix.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Loic PALLARDY <loic.pallardy@stericsson.com> Cc: Ludovic BARRE <ludovic.barre@stericsson.com> Cc: Omar Ramirez Luna <omar.luna@linaro.org> Cc: Guzman Lugo Fernando <fernando.lugo@ti.com> Cc: Anna Suman <s-anna@ti.com> Cc: Clark Rob <rob@ti.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Saravana Kannan <skannan@codeaurora.org> Cc: David Brown <davidb@codeaurora.org> Cc: Kieran Bingham <kieranbingham@gmail.com> Cc: Tony Lindgren <tony@atomide.com>
2012-03-06remoteproc: resource table overhaulOhad Ben-Cohen
The resource table is an array of 'struct fw_resource' members, where each resource entry is expressed as a single member of that array. This approach got us this far, but it has a few drawbacks: 1. Different resource entries end up overloading the same members of 'struct fw_resource' with different meanings. The resulting code is error prone and hard to read and maintain. 2. It's impossible to extend 'struct fw_resource' without breaking the existing firmware images (and we already want to: we can't introduce the new virito device resource entry with the current scheme). 3. It doesn't scale: 'struct fw_resource' must be as big as the largest resource entry type. As a result, smaller resource entries end up utilizing only small part of it. This is fixed by defining a dedicated structure for every resource type, and then converting the resource table to a list of type-value members. Instead of a rigid array of homogeneous structs, the resource table is turned into a collection of heterogeneous structures. This way: 1. Resource entries consume exactly the amount of bytes they need. 2. It's easy to extend: just create a new resource entry structure, and assign it a new type. 3. The code is easier to read and maintain: the structures' members names are meaningful. While we're at it, this patch has several other resource table changes: 1. The resource table gains a simple header which contains the number of entries in the table and their offsets within the table. This makes the parsing code simpler and easier to read. 2. A version member is added to the resource table. Should we change the format again, we'll bump up this version to prevent breakage with existing firmware images. 3. The VRING and VIRTIO_DEV resource entries are combined to a single VDEV entry. This paves the way to supporting multiple VDEV entries. 4. Since we don't really support 64-bit rprocs yet, convert two stray u64 members to u32. Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com> Cc: Brian Swetland <swetland@google.com> Cc: Iliyan Malchev <malchev@google.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Mark Grosen <mgrosen@ti.com> Cc: John Williams <john.williams@petalogix.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Loic PALLARDY <loic.pallardy@stericsson.com> Cc: Ludovic BARRE <ludovic.barre@stericsson.com> Cc: Omar Ramirez Luna <omar.luna@linaro.org> Cc: Guzman Lugo Fernando <fernando.lugo@ti.com> Cc: Anna Suman <s-anna@ti.com> Cc: Clark Rob <rob@ti.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Saravana Kannan <skannan@codeaurora.org> Cc: David Brown <davidb@codeaurora.org> Cc: Kieran Bingham <kieranbingham@gmail.com> Cc: Tony Lindgren <tony@atomide.com>
2012-02-08remoteproc: add framework for controlling remote processorsOhad Ben-Cohen
Modern SoCs typically employ a central symmetric multiprocessing (SMP) application processor running Linux, with several other asymmetric multiprocessing (AMP) heterogeneous processors running different instances of operating system, whether Linux or any other flavor of real-time OS. Booting a remote processor in an AMP configuration typically involves: - Loading a firmware which contains the OS image - Allocating and providing it required system resources (e.g. memory) - Programming an IOMMU (when relevant) - Powering on the device This patch introduces a generic framework that allows drivers to do that. In the future, this framework will also include runtime power management and error recovery. Based on (but now quite far from) work done by Fernando Guzman Lugo <fernando.lugo@ti.com>. ELF loader was written by Mark Grosen <mgrosen@ti.com>, based on msm's Peripheral Image Loader (PIL) by Stephen Boyd <sboyd@codeaurora.org>. Designed with Brian Swetland <swetland@google.com>. Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com> Acked-by: Grant Likely <grant.likely@secretlab.ca> Cc: Brian Swetland <swetland@google.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Tony Lindgren <tony@atomide.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg KH <greg@kroah.com> Cc: Stephen Boyd <sboyd@codeaurora.org>