Hi Mike, On Tue, Oct 23, 2018 at 10:53:50AM +0000, Mike Looijmans wrote: > On 23-10-18 11:01, Moritz Fischer wrote: > > Hi Mike, > > > > seems like a good usecase (though uncommon), question below > > Usecases for ICAP: > - It's considerably faster than PCAP > - Self-repairing logic (e.g. single-event upsets) > - Being programmed from a remote FPGA > - Programming through another bus (e.g. PCIe) Yeah, I wasn't saying it's a bad usecase, just not super common :) > > > > > > On Tue, Oct 23, 2018 at 08:31:19AM +0200, Mike Looijmans wrote: > >> The Xilinx Zynq FPGA driver takes ownership of the PR interface, making > >> it impossible to use the ICAP interface for partial reconfiguration. > >> > >> This patch changes the driver to only activate PR over PCAP while the > >> device is actively being accessed by the driver for programming. > >> > >> This allows both PCAP and ICAP interfaces to be used for PR. > >> > >> Signed-off-by: Mike Looijmans <mike.looijmans@xxxxxxxx> > >> --- > >> drivers/fpga/zynq-fpga.c | 4 ++++ > >> 1 file changed, 4 insertions(+) > >> > >> diff --git a/drivers/fpga/zynq-fpga.c b/drivers/fpga/zynq-fpga.c > >> index 3110e00..f6c205a 100644 > >> --- a/drivers/fpga/zynq-fpga.c > >> +++ b/drivers/fpga/zynq-fpga.c > >> @@ -497,6 +497,10 @@ static int zynq_fpga_ops_write_complete(struct fpga_manager *mgr, > >> int err; > >> u32 intr_status; > >> > >> + /* Release 'PR' control back to the ICAP */ > >> + zynq_fpga_write(priv, CTRL_OFFSET, > >> + zynq_fpga_read(priv, CTRL_OFFSET) & ~CTRL_PCAP_PR_MASK); > >> + > > > > Shouldn't that be after the below stanza that enables the clock? > > I'm actually not sure, and I did not encounter any problems while testing > this, but it's easier to just move it than to find out, so I'll go for "yes, > let's enable the clock first". > I'll await a bit more feedback and post a v2 for that. Ok, I had suspected you tested it and probably didn't run into issues, but just wanted to make sure we think about it. If you don't mind, swap it around as I suggested just to be safe. With that change feel free to add my Reviewed-by: Moritz Fischer <mdf@xxxxxxxxxx> in your v2. Thanks for the patch, Moritz
