ice: fall back to TCXO on TSPLL lock fail

jira LE-4694
Rebuild_History Non-Buildable kernel-6.12.0-55.43.1.el10_0
commit-author Karol Kolacinski <karol.kolacinski@intel.com>
commit 84b8694

TSPLL can fail when trying to lock to TIME_REF as a clock source, e.g.
when the external clock source is not stable or connected to the board.
To continue operation after failure, try to lock again to internal TCXO
and inform user about this.

	Reviewed-by: Milena Olech <milena.olech@intel.com>
	Signed-off-by: Karol Kolacinski <karol.kolacinski@intel.com>
	Tested-by: Rinitha S <sx.rinitha@intel.com>
	Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
(cherry picked from commit 84b8694)
	Signed-off-by: Jonathan Maple <jmaple@ciq.com>

Author: PlaidCat

drivers/net/ethernet/intel/ice/ice_tspll.c

@@ -605,5 +605,17 @@ int ice_tspll_init(struct ice_hw *hw)
 	/* Configure the TSPLL using the parameters from the function
 	 * capabilities.
 	 */
-	return ice_tspll_cfg(hw, tspll_freq, clk_src);
+	err = ice_tspll_cfg(hw, tspll_freq, clk_src);
+	if (err) {
+		dev_warn(ice_hw_to_dev(hw), "Failed to lock TSPLL to predefined frequency. Retrying with fallback frequency.\n");
+
+		/* Try to lock to internal TCXO as a fallback. */
+		tspll_freq = ice_tspll_default_freq(hw->mac_type);
+		clk_src = ICE_CLK_SRC_TCXO;
+		err = ice_tspll_cfg(hw, tspll_freq, clk_src);
+		if (err)
+			dev_warn(ice_hw_to_dev(hw), "Failed to lock TSPLL to fallback frequency.\n");
+	}
+
+	return err;
 }