[PATCH net-next v2 04/14] net: pcs: xpcs: re-order xpcs_pre_config() to update after the reset
flat view
STALE65d
From: Alex Elder <hidden>
Date: 2026-06-05 01:00:41
Also in:
bpf, linux-arm-kernel, linux-arm-msm, linux-devicetree, linux-gpio, lkml
Subsystem:
ethernet phy library, networking drivers, synopsys designware ethernet xpcs driver, the rest · Maintainers:
Andrew Lunn, Heiner Kallweit, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Revision v2 of 2 in this series.
Revisions (2)
- v1 [diff vs current]
- v2 current
From: Daniel Thompson <redacted> Currently, on Wangxun platforms, the XPCS is configured during the call to xpcs_switch_interface_mode() and, if the need_reset flag is set, the XPCS is reset and the configuration will be lost. This is harmless at present because need_reset will never actually be set on these platforms. Nevertheless having xpcs_switch_interface_mode() on the wrong side of the reset is an obstacle for future changes where wiping out programmed configuration with a reset could be harmful. Reorder xpcs_pre_config() to allow the reset can happen before we switch interface mode. To make this work we have to hoist the special case logic for SGMII into the parent function. Signed-off-by: Daniel Thompson <redacted> Signed-off-by: Alex Elder <redacted> --- drivers/net/pcs/pcs-xpcs.c | 56 ++++++++++++++++++++------------------ 1 file changed, 30 insertions(+), 26 deletions(-)
diff --git a/drivers/net/pcs/pcs-xpcs.c b/drivers/net/pcs/pcs-xpcs.c
index e69fa2f0a0e8d..76c04372b5b50 100644
--- a/drivers/net/pcs/pcs-xpcs.c
+++ b/drivers/net/pcs/pcs-xpcs.c@@ -705,46 +705,50 @@ static void xpcs_get_interfaces(struct dw_xpcs *xpcs, unsigned long *interfaces) static int xpcs_switch_interface_mode(struct dw_xpcs *xpcs, phy_interface_t interface) { - int ret = 0; + /* Wangxun provides a full alternative implementation to handle quirks */ + if (xpcs->info.pma == WX_TXGBE_XPCS_PMA_10G_ID) + return txgbe_xpcs_switch_mode(xpcs, interface); - if (xpcs->info.pma == WX_TXGBE_XPCS_PMA_10G_ID) { - ret = txgbe_xpcs_switch_mode(xpcs, interface); - } else if (xpcs->interface != interface) { - if (interface == PHY_INTERFACE_MODE_SGMII) - xpcs->need_reset = true; - xpcs->interface = interface; - } + xpcs->interface = interface; - return ret; + return 0; } static void xpcs_pre_config(struct phylink_pcs *pcs, phy_interface_t interface) { struct dw_xpcs *xpcs = phylink_pcs_to_xpcs(pcs); const struct dw_xpcs_compat *compat; + bool force_reset; int ret; + /* + * According to the XPCS datasheet, a soft reset is required to initiate + * Clause 37 auto-negotiation when the XPCS switches interface modes. + */ + force_reset = interface == PHY_INTERFACE_MODE_SGMII; + + if (force_reset || xpcs->need_reset) { + compat = xpcs_find_compat(xpcs, interface); + if (!compat) { + dev_err(&xpcs->mdiodev->dev, "unsupported interface %s\n", + phy_modes(interface)); + return; + } + + ret = xpcs_soft_reset(xpcs, compat); + if (ret) { + dev_err(&xpcs->mdiodev->dev, "soft reset failed: %pe\n", + ERR_PTR(ret)); + return; + } + + xpcs->need_reset = false; + } + ret = xpcs_switch_interface_mode(xpcs, interface); if (ret) dev_err(&xpcs->mdiodev->dev, "switch interface failed: %pe\n", ERR_PTR(ret)); - - if (!xpcs->need_reset) - return; - - compat = xpcs_find_compat(xpcs, interface); - if (!compat) { - dev_err(&xpcs->mdiodev->dev, "unsupported interface %s\n", - phy_modes(interface)); - return; - } - - ret = xpcs_soft_reset(xpcs, compat); - if (ret) - dev_err(&xpcs->mdiodev->dev, "soft reset failed: %pe\n", - ERR_PTR(ret)); - - xpcs->need_reset = false; } static int xpcs_config_aneg_c37_sgmii(struct dw_xpcs *xpcs,
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2.51.0