zynq-fpga: Only route PR via PCAP when required

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@topic.nl>
Reviewed-by: Moritz Fischer <mdf@kernel.org>
Acked-by: Alan Tull <atull@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/fpga/zynq-fpga.c b/drivers/fpga/zynq-fpga.c
index bb82efeebb9d5bd9dd135c247bf30a82a55b3410..57b0e6775958ef507d504edb5b18df5e74e7dfd2 100644 (file)
--- a/drivers/fpga/zynq-fpga.c
+++ b/drivers/fpga/zynq-fpga.c
@@ -501,6 +501,10 @@ static int zynq_fpga_ops_write_complete(struct fpga_manager *mgr,
        if (err)
                return err;
 
+       /* Release 'PR' control back to the ICAP */
+       zynq_fpga_write(priv, CTRL_OFFSET,
+               zynq_fpga_read(priv, CTRL_OFFSET) & ~CTRL_PCAP_PR_MASK);
+
        err = zynq_fpga_poll_timeout(priv, INT_STS_OFFSET, intr_status,
                                     intr_status & IXR_PCFG_DONE_MASK,
                                     INIT_POLL_DELAY,