On 19-01-21, 12:44, Dave Jiang wrote: > > On 1/19/2021 9:38 AM, Vinod Koul wrote: > > On 18-01-21, 10:06, Dave Jiang wrote: > > > On 1/16/2021 11:51 PM, Vinod Koul wrote: > > > > On 15-01-21, 15:01, Dave Jiang wrote: > > > > > Add a module parameter that overrides the SVA feature enabling. This keeps > > > > > the driver in legacy mode even when intel_iommu=sm_on is set. In this mode, > > > > > the descriptor fields must be programmed with dma_addr_t from the Linux DMA > > > > > API for source, destination, and completion descriptors. > > > > > > > > > > Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx> > > > > > --- > > > > > drivers/dma/idxd/init.c | 8 +++++++- > > > > > 1 file changed, 7 insertions(+), 1 deletion(-) > > > > > > > > > > diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c > > > > > index 25cc947c6179..9687a24ff982 100644 > > > > > --- a/drivers/dma/idxd/init.c > > > > > +++ b/drivers/dma/idxd/init.c > > > > > @@ -26,6 +26,10 @@ MODULE_VERSION(IDXD_DRIVER_VERSION); > > > > > MODULE_LICENSE("GPL v2"); > > > > > MODULE_AUTHOR("Intel Corporation"); > > > > > +static bool sva = true; > > > > > +module_param(sva, bool, 0644); > > > > > +MODULE_PARM_DESC(sva, "Toggle SVA support on/off"); > > > > Documentation for this please.. > > > Just comments or is there somewhere specific for driver module parameter > > > documentations? > > All the parameters are supposed to be documented in Documentation/admin-guide/kernel-parameters.txt > > It seems to be for core kernel components and subsystems, and not specific > device drivers. I'm not seeing any of the dmaengine driver module params > being in this doc after grepping in drivers/dma. Yeah we should fix that as well :) -- ~Vinod