[PATCH net-next 8/8] net: stmmac: report PCS configuration changes

["Russell King (Oracle)" <rmk+kernel@armlinux.org.uk>]

Report if/when qcom-ethqos changes the PCS configuration. With phylink
now setting the PCS configuration, there should be no need for drivers
to change this.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
index b2b12d34b3dd..e1160bc8a63d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
@@ -71,6 +71,7 @@ static inline void dwmac_ctrl_ane(void __iomem *ioaddr, u32 reg, bool ane,
 				  bool srgmi_ral)
 {
 	u32 value = readl(ioaddr + GMAC_AN_CTRL(reg));
+	u32 old = value, diff;
 
 	/* Enable and restart the Auto-Negotiation */
 	if (ane)
@@ -85,5 +86,19 @@ static inline void dwmac_ctrl_ane(void __iomem *ioaddr, u32 reg, bool ane,
 		value |= GMAC_AN_CTRL_SGMRAL;
 
 	writel(value, ioaddr + GMAC_AN_CTRL(reg));
+
+	diff = old ^ value;
+	if (diff & ~GMAC_AN_CTRL_RAN) {
+		pr_warn("dwmac: PCS configuration changed from phylink by glue, please report: 0x%08x -> 0x%08x\n",
+			old & ~GMAC_AN_CTRL_RAN, value & ~GMAC_AN_CTRL_RAN);
+#define REPORT_BIT(x) \
+		if (diff & GMAC_AN_CTRL_##x) \
+			pr_warn("dwmac: %8s %u -> %u\n", #x, \
+				!!(old & GMAC_AN_CTRL_##x), \
+				!!(value & GMAC_AN_CTRL_##x))
+		REPORT_BIT(ANE);
+		REPORT_BIT(SGMRAL);
+#undef REPORT_BIT
+	}
 }
 #endif /* __STMMAC_PCS_H__ */
-- 
2.47.3