diff options
Diffstat (limited to 'drivers/staging/vc04_services/interface/vchi')
| -rw-r--r-- | drivers/staging/vc04_services/interface/vchi/TODO | 50 | ||||
| -rw-r--r-- | drivers/staging/vc04_services/interface/vchi/vchi.h | 25 |
2 files changed, 56 insertions, 19 deletions
diff --git a/drivers/staging/vc04_services/interface/vchi/TODO b/drivers/staging/vc04_services/interface/vchi/TODO new file mode 100644 index 000000000000..03aa65183b25 --- /dev/null +++ b/drivers/staging/vc04_services/interface/vchi/TODO @@ -0,0 +1,50 @@ +1) Port to aarch64 + +This driver won't be very useful unless we also have it working on +Raspberry Pi 3. This requires, at least: + + - Figure out an alternative to the dmac_map_area() hack. + + - Decide what to use instead of dsb(). + + - Do something about (int) cast of bulk->data in + vchiq_bulk_transfer(). + + bulk->data is a bus address going across to the firmware. We know + our bus addresses are <32bit. + +2) Write a DT binding doc and get the corresponding DT node merged to + bcm2835. + +This will let the driver probe when enabled. + +3) Import drivers using VCHI. + +VCHI is just a tool to let drivers talk to the firmware. Here are +some of the ones we want: + + - vc_mem (https://github.com/raspberrypi/linux/blob/rpi-4.4.y/drivers/char/broadcom/vc_mem.c) + + This driver is what the vcdbg userspace program uses to set up its + requests to the firmware, which are transmitted across VCHIQ. vcdbg + is really useful for debugging firmware interactions. + + - bcm2835-camera (https://github.com/raspberrypi/linux/tree/rpi-4.4.y/drivers/media/platform/bcm2835) + + This driver will let us get images from the camera using the MMAL + protocol over VCHI. + + - VCSM (https://github.com/raspberrypi/linux/tree/rpi-4.4.y/drivers/char/broadcom/vc_sm) + + This driver is used for talking about regions of VC memory across + firmware protocols including VCHI. We'll want to extend this driver + to manage these buffers as dmabufs so that we can zero-copy import + camera images into vc4 for rendering/display. + +4) Garbage-collect unused code + +One of the reasons this driver wasn't upstreamed previously was that +there's a lot code that got built that's probably unnecessary these +days. Once we have the set of VCHI-using drivers we want in tree, we +should be able to do a sweep of the code to see what's left that's +unused. diff --git a/drivers/staging/vc04_services/interface/vchi/vchi.h b/drivers/staging/vc04_services/interface/vchi/vchi.h index 1b17e98f7379..d6937288210c 100644 --- a/drivers/staging/vc04_services/interface/vchi/vchi.h +++ b/drivers/staging/vc04_services/interface/vchi/vchi.h @@ -226,25 +226,12 @@ extern int32_t vchi_service_set_option( const VCHI_SERVICE_HANDLE_T handle, int value); // Routine to send a message across a service -extern int32_t vchi_msg_queue( VCHI_SERVICE_HANDLE_T handle, - const void *data, - uint32_t data_size, - VCHI_FLAGS_T flags, - void *msg_handle ); - -// scatter-gather (vector) and send message -int32_t vchi_msg_queuev_ex( VCHI_SERVICE_HANDLE_T handle, - VCHI_MSG_VECTOR_EX_T *vector, - uint32_t count, - VCHI_FLAGS_T flags, - void *msg_handle ); - -// legacy scatter-gather (vector) and send message, only handles pointers -int32_t vchi_msg_queuev( VCHI_SERVICE_HANDLE_T handle, - VCHI_MSG_VECTOR_T *vector, - uint32_t count, - VCHI_FLAGS_T flags, - void *msg_handle ); +extern int32_t + vchi_msg_queue(VCHI_SERVICE_HANDLE_T handle, + ssize_t (*copy_callback)(void *context, void *dest, + size_t offset, size_t maxsize), + void *context, + uint32_t data_size); // Routine to receive a msg from a service // Dequeue is equivalent to hold, copy into client buffer, release |