net: fec: fix MAC internal delay doesn't work

This patch intends to fix MAC internal delay doesn't work, due to use
of_property_read_u32() incorrectly, and improve this feature a bit:
1) check the delay value if valid, only program register when it's 2000ps.
2) only enable "enet_2x_txclk" clock when require MAC internal delay.

Fixes: fc539459e900 ("net: fec: add MAC internal delayed clock feature support")
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Link: https://lore.kernel.org/r/20210803052424.19008-1-qiangqing.zhang@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index 40ea318..1201c13 100644 (file)
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -2042,6 +2042,34 @@ failed_clk_ptp:
        return ret;
 }
 
+static int fec_enet_parse_rgmii_delay(struct fec_enet_private *fep,
+                                     struct device_node *np)
+{
+       u32 rgmii_tx_delay, rgmii_rx_delay;
+
+       /* For rgmii tx internal delay, valid values are 0ps and 2000ps */
+       if (!of_property_read_u32(np, "tx-internal-delay-ps", &rgmii_tx_delay)) {
+               if (rgmii_tx_delay != 0 && rgmii_tx_delay != 2000) {
+                       dev_err(&fep->pdev->dev, "The only allowed RGMII TX delay values are: 0ps, 2000ps");
+                       return -EINVAL;
+               } else if (rgmii_tx_delay == 2000) {
+                       fep->rgmii_txc_dly = true;
+               }
+       }
+
+       /* For rgmii rx internal delay, valid values are 0ps and 2000ps */
+       if (!of_property_read_u32(np, "rx-internal-delay-ps", &rgmii_rx_delay)) {
+               if (rgmii_rx_delay != 0 && rgmii_rx_delay != 2000) {
+                       dev_err(&fep->pdev->dev, "The only allowed RGMII RX delay values are: 0ps, 2000ps");
+                       return -EINVAL;
+               } else if (rgmii_rx_delay == 2000) {
+                       fep->rgmii_rxc_dly = true;
+               }
+       }
+
+       return 0;
+}
+
 static int fec_enet_mii_probe(struct net_device *ndev)
 {
        struct fec_enet_private *fep = netdev_priv(ndev);
@@ -3719,7 +3747,6 @@ fec_probe(struct platform_device *pdev)
        char irq_name[8];
        int irq_cnt;
        struct fec_devinfo *dev_info;
-       u32 rgmii_delay;
 
        fec_enet_get_queue_num(pdev, &num_tx_qs, &num_rx_qs);
 
@@ -3777,12 +3804,6 @@ fec_probe(struct platform_device *pdev)
        if (ret)
                goto failed_stop_mode;
 
-       /* For rgmii internal delay, valid values are 0ps and 2000ps */
-       if (of_property_read_u32(np, "tx-internal-delay-ps", &rgmii_delay))
-               fep->rgmii_txc_dly = true;
-       if (of_property_read_u32(np, "rx-internal-delay-ps", &rgmii_delay))
-               fep->rgmii_rxc_dly = true;
-
        phy_node = of_parse_phandle(np, "phy-handle", 0);
        if (!phy_node && of_phy_is_fixed_link(np)) {
                ret = of_phy_register_fixed_link(np);
@@ -3806,6 +3827,10 @@ fec_probe(struct platform_device *pdev)
                fep->phy_interface = interface;
        }
 
+       ret = fec_enet_parse_rgmii_delay(fep, np);
+       if (ret)
+               goto failed_rgmii_delay;
+
        fep->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
        if (IS_ERR(fep->clk_ipg)) {
                ret = PTR_ERR(fep->clk_ipg);
@@ -3835,9 +3860,11 @@ fec_probe(struct platform_device *pdev)
        fep->clk_ref_rate = clk_get_rate(fep->clk_ref);
 
        /* clk_2x_txclk is optional, depends on board */
-       fep->clk_2x_txclk = devm_clk_get(&pdev->dev, "enet_2x_txclk");
-       if (IS_ERR(fep->clk_2x_txclk))
-               fep->clk_2x_txclk = NULL;
+       if (fep->rgmii_txc_dly || fep->rgmii_rxc_dly) {
+               fep->clk_2x_txclk = devm_clk_get(&pdev->dev, "enet_2x_txclk");
+               if (IS_ERR(fep->clk_2x_txclk))
+                       fep->clk_2x_txclk = NULL;
+       }
 
        fep->bufdesc_ex = fep->quirks & FEC_QUIRK_HAS_BUFDESC_EX;
        fep->clk_ptp = devm_clk_get(&pdev->dev, "ptp");
@@ -3955,6 +3982,7 @@ failed_clk_ahb:
 failed_clk_ipg:
        fec_enet_clk_enable(ndev, false);
 failed_clk:
+failed_rgmii_delay:
        if (of_phy_is_fixed_link(np))
                of_phy_deregister_fixed_link(np);
        of_node_put(phy_node);