diff mbox series

[net,v2,3/9] net: axienet: reset core on initialization prior to MDIO access

Message ID 20220112173700.873002-4-robert.hancock@calian.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series Xilinx axienet fixes | expand

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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 success CCed 7 of 7 maintainers
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 success total: 0 errors, 0 warnings, 0 checks, 11 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Robert Hancock Jan. 12, 2022, 5:36 p.m. UTC
In some cases where the Xilinx Ethernet core was used in 1000Base-X or
SGMII modes, which use the internal PCS/PMA PHY, and the MGT
transceiver clock source for the PCS was not running at the time the
FPGA logic was loaded, the core would come up in a state where the
PCS could not be found on the MDIO bus. To fix this, the Ethernet core
(including the PCS) should be reset after enabling the clocks, prior to
attempting to access the PCS using of_mdio_find_device.

Fixes: 1a02556086fc (net: axienet: Properly handle PCS/PMA PHY for 1000BaseX mode)
Signed-off-by: Robert Hancock <robert.hancock@calian.com>
---
 drivers/net/ethernet/xilinx/xilinx_axienet_main.c | 5 +++++
 1 file changed, 5 insertions(+)

Comments

Andrew Lunn Jan. 12, 2022, 7:21 p.m. UTC | #1
On Wed, Jan 12, 2022 at 11:36:54AM -0600, Robert Hancock wrote:
> In some cases where the Xilinx Ethernet core was used in 1000Base-X or
> SGMII modes, which use the internal PCS/PMA PHY, and the MGT
> transceiver clock source for the PCS was not running at the time the
> FPGA logic was loaded, the core would come up in a state where the
> PCS could not be found on the MDIO bus. To fix this, the Ethernet core
> (including the PCS) should be reset after enabling the clocks, prior to
> attempting to access the PCS using of_mdio_find_device.
> 
> Fixes: 1a02556086fc (net: axienet: Properly handle PCS/PMA PHY for 1000BaseX mode)
> Signed-off-by: Robert Hancock <robert.hancock@calian.com>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew
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 f425a8404a9b..f4ae035bed35 100644
--- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
+++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
@@ -2055,6 +2055,11 @@  static int axienet_probe(struct platform_device *pdev)
 	lp->coalesce_count_rx = XAXIDMA_DFT_RX_THRESHOLD;
 	lp->coalesce_count_tx = XAXIDMA_DFT_TX_THRESHOLD;
 
+	/* Reset core now that clocks are enabled, prior to accessing MDIO */
+	ret = __axienet_device_reset(lp);
+	if (ret)
+		goto cleanup_clk;
+
 	lp->phy_node = of_parse_phandle(pdev->dev.of_node, "phy-handle", 0);
 	if (lp->phy_node) {
 		ret = axienet_mdio_setup(lp);