We have been using RPMSG_SDB driver from LogicAnalyzer example. By default, RPMSG_SDB uses common CMA area for allocating buffers via
dma_alloc_coherent()
We want to allocate SDB personal buffers from reserved memory regions. We adapted both device-tree and SDB driver. Device-tree snippet:
reserved-memory {
shared_buffers: shared_buffers@D2000000 {
compatible = "shared-dma-pool";
reg = <0xD2000000 0x400000>;
no-map;
};
};
rpmsg-sdb@0 {
compatible = "fmx,rpmsg-sdb";
memory-region = <&shared_buffers>;
};
SDB driver compatible string:
static struct rpmsg_device_id rpmsg_driver_sdb_id_table[] = {
{ .name = "rpmsg-sdb-channel" },
{ },
};
static struct of_device_id rpmsg_driver_sdb_dt[] = {
{ .name = "rpmsg-sdb-channel",
.compatible = "fmx,rpmsg-sdb" },
{ },
};
MODULE_DEVICE_TABLE(rpmsg, rpmsg_driver_sdb_id_table);
static struct rpmsg_driver rpmsg_sdb_rmpsg_drv = {
.drv.name = KBUILD_MODNAME,
.drv.owner = THIS_MODULE,
.drv.of_match_table = rpmsg_driver_sdb_dt,
.id_table = rpmsg_driver_sdb_id_table,
.probe = rpmsg_sdb_drv_probe,
.callback = rpmsg_sdb_drv_cb,
.remove = rpmsg_sdb_drv_remove,
};
SDB driver memory allocation inside rpmsg_sdb_drv_init(void):
ret = of_reserved_mem_device_init(rpmsg_sdb_dev);
It fails with error -22 (EINVAL). What might be the culprit ?
