diff mbox series

[net,v3,2/9] net: axienet: Wait for PhyRstCmplt after core reset

Message ID 20220118214132.357349-3-robert.hancock@calian.com (mailing list archive)
State Accepted
Delegated to: Netdev Maintainers
Headers show
Series Xilinx axienet fixes | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net
netdev/fixes_present success Fixes tag present in non-next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 2 this patch: 2
netdev/cc_maintainers fail 1 blamed authors not CCed: ariane.keller@tik.ee.ethz.ch; 1 maintainers not CCed: ariane.keller@tik.ee.ethz.ch
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 2 this patch: 2
netdev/checkpatch warning WARNING: line length of 84 exceeds 80 columns WARNING: line length of 87 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Robert Hancock Jan. 18, 2022, 9:41 p.m. UTC
When resetting the device, wait for the PhyRstCmplt bit to be set
in the interrupt status register before continuing initialization, to
ensure that the core is actually ready. When using an external PHY, this
also ensures we do not start trying to access the PHY while it is still
in reset. The PHY reset is initiated by the core reset which is
triggered just above, but remains asserted for 5ms after the core is
reset according to the documentation.

The MgtRdy bit could also be waited for, but unfortunately when using
7-series devices, the bit does not appear to work as documented (it
seems to behave as some sort of link state indication and not just an
indication the transceiver is ready) so it can't really be relied on for
this purpose.

Fixes: 8a3b7a252dca9 ("drivers/net/ethernet/xilinx: added Xilinx AXI Ethernet driver")
Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
---
 drivers/net/ethernet/xilinx/xilinx_axienet_main.c | 10 ++++++++++
 1 file changed, 10 insertions(+)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
index 9c5b24af61fa..3a2d7e8c3f66 100644
--- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
+++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
@@ -516,6 +516,16 @@  static int __axienet_device_reset(struct axienet_local *lp)
 		return ret;
 	}
 
+	/* Wait for PhyRstCmplt bit to be set, indicating the PHY reset has finished */
+	ret = read_poll_timeout(axienet_ior, value,
+				value & XAE_INT_PHYRSTCMPLT_MASK,
+				DELAY_OF_ONE_MILLISEC, 50000, false, lp,
+				XAE_IS_OFFSET);
+	if (ret) {
+		dev_err(lp->dev, "%s: timeout waiting for PhyRstCmplt\n", __func__);
+		return ret;
+	}
+
 	return 0;
 }