[PATCH v2] zynq-fpga: Only route PR via PCAP when required

[mike.looijmans@topic.nl (Mike Looijmans)]

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>
---
v2: Move the register setting in between the clock enable/disable

 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..ff3a427 100644
--- 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,
-- 
1.9.1