On Wed, Jan 27, 2021 at 10:21:24AM +0100, Arnaud POULIQUEN wrote: > Hi Mathieu > > On 12/18/20 6:32 PM, Mathieu Poirier wrote: > > Following the work done here [1], this set provides support for the > > remoteproc core to release resources associated with a remote processor > > without having to switch it off. That way a platform driver can be removed > > or the application processor power cycled while the remote processor is > > still operating. > > > > Of special interest in this series are patches 5 and 6 where getting the > > address of the resource table installed by an eternal entity if moved to > > the core. This is to support scenarios where a remote process has been > > booted by the core but is being detached. To re-attach the remote > > processor, the address of the resource table needs to be known at a later > > time than the platform driver's probe() function. > > > > Applies cleanly on v5.10 > > > > Thanks, > > Mathieu > > > > [1]. https://lkml.org/lkml/2020/7/14/1600 > > > > ---- > > New for v4: > > - Made binding description OS agnostic (Rob) > > - Added functionality to set the external resource table in the core > > - Fixed a crash when detaching (Arnaud) > > - Fixed error code propagation in rproc_cdev_relase() and rproc_del() (Arnaud) > > - Added RB tags > > > I tested you series, attach and detach is working well. > > Then I faced issue when tried to re-attach after a detach. > Right, in this case don't expect the re-attach to work properly because function stm32_rproc_detach() does not exist. As such the M4 doesn't put itself back in "wait-for-attach" mode as it does when booted by the boot loader. If I remember correctly we talked about that during an earlier conversation and we agreed FW support would be needed to properly test the re-attach. > But I don't know if this feature has to be supported in this step. > > The 2 issues I found are: > > 1) memory carveouts are released on detach so need to be reinitialized. > The use of prepare/unprepare for the attach and detach would solve the issue but > probably need to add parameter to differentiate a start/stop from a attach/detach. > > 2) The vrings in the loaded resource table (so no cached) has to be properly > reinitialized. In rproc_free_vring the vring da is set to 0 that is then > considered as a fixed address. > > Here is a fix which works on the stm32 platform > > @@ -425,7 +425,7 @@ void rproc_free_vring(struct rproc_vring *rvring) > */ > if (rproc->table_ptr) { > rsc = (void *)rproc->table_ptr + rvring->rvdev->rsc_offset; > - rsc->vring[idx].da = 0; > + rsc->vring[idx].da = FW_RSC_ADDR_ANY; > rsc->vring[idx].notifyid = -1; > } > } In light of the above let me know if these two issues are still relevant. If so I'll investigate further. Thanks, Mathieu > > Here, perhaps a better alternative would be to make a cached copy on attach > before updating it. On the next attach, the cached copy would be copied as it is > done in rproc_start. > > Thanks, > Arnaud > > > > > > Mathieu Poirier (17): > > dt-bindings: remoteproc: Add bindind to support autonomous processors > > remoteproc: Re-check state in rproc_shutdown() > > remoteproc: Remove useless check in rproc_del() > > remoteproc: Rename function rproc_actuate() > > remoteproc: Add new get_loaded_rsc_table() remoteproc operation > > remoteproc: stm32: Move resource table setup to rproc_ops > > remoteproc: Add new RPROC_ATTACHED state > > remoteproc: Properly represent the attached state > > remoteproc: Properly deal with a kernel panic when attached > > remoteproc: Add new detach() remoteproc operation > > remoteproc: Introduce function __rproc_detach() > > remoteproc: Introduce function rproc_detach() > > remoteproc: Add return value to function rproc_shutdown() > > remoteproc: Properly deal with a stop request when attached > > remoteproc: Properly deal with a start request when attached > > remoteproc: Properly deal with detach request > > remoteproc: Refactor rproc delete and cdev release path > > > > .../bindings/remoteproc/remoteproc-core.yaml | 27 +++ > > drivers/remoteproc/remoteproc_cdev.c | 32 ++- > > drivers/remoteproc/remoteproc_core.c | 211 +++++++++++++++--- > > drivers/remoteproc/remoteproc_internal.h | 8 + > > drivers/remoteproc/remoteproc_sysfs.c | 20 +- > > drivers/remoteproc/stm32_rproc.c | 147 ++++++------ > > include/linux/remoteproc.h | 24 +- > > 7 files changed, 344 insertions(+), 125 deletions(-) > > create mode 100644 Documentation/devicetree/bindings/remoteproc/remoteproc-core.yaml > >