path: root/Documentation/remoteproc.txt
AgeCommit message (Collapse)Author
2012-09-18remoteproc: add rproc_report_crash function to notify rproc crashesFernando Guzman Lugo
Allow low-level remoteproc drivers to report rproc crashes by exporting a new rproc_report_crash() function (invoking this from non-rproc drivers is probably wrong, and should be carefully scrutinized if ever needed). rproc_report_crash() can be called from any context; it offloads the tasks of handling the crash to a separate thread. Handling the crash from a separate thread is helpful because: - Ability to call invoke rproc_report_crash() from atomic context, due to the fact that many crashes trigger an interrupt, so this function can be called directly from ISR context. - Avoiding deadlocks which could happen if rproc_report_crash() is called from a function which indirectly holds the rproc lock. Handling the crash might involve: - Remoteproc register dump - Remoteproc stack dump - Remoteproc core dump - Saving Remoteproc traces so they can be read after the crash - Reseting the remoteproc in order to make it functional again (hard recovery) Right now, we only print the crash type which was detected, and only the mmufault type is supported. Remoteproc low-level drivers can add more types when needed. Signed-off-by: Fernando Guzman Lugo <fernando.lugo@ti.com> [ohad: some commentary, white space and commit log changes] Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
2012-07-06remoteproc: adopt the driver core's alloc/add/del/put namingOhad Ben-Cohen
To make remoteproc's API more intuitive for developers, we adopt the driver core's naming, i.e. alloc -> add -> del -> put. We'll also add register/unregister when their first user shows up. Otherwise - there's no functional change here. Suggested by Russell King <linux@arm.linux.org.uk>. Cc: Russell King <linux@arm.linux.org.uk> Cc: Fernando Guzman Lugo <fernando.lugo@ti.com> Cc: Sjur Brændeland <sjur.brandeland@stericsson.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
2012-07-06remoteproc: remove the get_by_name/put APIOhad Ben-Cohen
Remove rproc_get_by_name() and rproc_put(), and the associated remoteproc infrastructure that supports it (i.e. klist and friends), because: 1. No one uses them 2. Using them is highly discouraged, and any potential user will be deeply scrutinized and encouraged to move. If a user, that absolutely can't live with the direct boot/shutdown model, does show up one day, then bringing this functionality back is going to be trivial. At this point though, keeping this functionality around is way too much of a maintenance burden. Cc: Sjur Brændeland <sjur.brandeland@stericsson.com> Cc: Loic Pallardy <loic.pallardy@stericsson.com> Cc: Ludovic BARRE <ludovic.barre@stericsson.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Fernando Guzman Lugo <fernando.lugo@ti.com> Cc: Suman Anna <s-anna@ti.com> Cc: Mark Grosen <mgrosen@ti.com> Acked-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
2012-07-06remoteproc: simplify unregister/free interfacesOhad Ben-Cohen
Simplify the unregister/free interfaces, and make them easier to understand and use, by moving to a symmetric and consistent alloc() -> register() -> unregister() -> free() flow. To create and register an rproc instance, one needed to invoke rproc_alloc() followed by rproc_register(). To unregister and free an rproc instance, one now needs to invoke rproc_unregister() followed by rproc_free(). Cc: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
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>