[PATCH net-next v4 06/10] net: stmmac: mediatek: use standard internal delay properties

[Louis-Alexis Eyraud <louisalexis.eyraud@collabora.com>]

Currently, the mediatek-dwmac driver uses the 'mediatek,rx-delay-ps'
and 'mediatek,tx-delay-ps' vendor properties for configuring the RX and
TX internal clock delays for all its supported PHY modes (MII, RMII,
and RGMII).

The generic Ethernet controller bindings provide 'rx-internal-delay-ps'
and 'tx-internal-delay-ps' standard properties to describe the RGMII RX
and TX internal clock delays. Their use is now recommended, rather than
existing vendor properties.
There is no equivalent standard properties for RMII and MII case at the
moment.

So, add in driver data separate config values for MII/RMII and RGMII
delays and modify mediatek_dwmac_config_dt, used to parse devicetree
to populate and check these configs with the following logic:
 - read vendor properties for MII and RMII delay timings
 - read standard properties for RGMII delay timings
 - if not available, fallback to vendor values

Also, modify mt2712/mt8195_set_delay to use these new separate config
values.

Signed-off-by: Louis-Alexis Eyraud <louisalexis.eyraud@collabora.com>
---
 .../net/ethernet/stmicro/stmmac/dwmac-mediatek.c   | 87 +++++++++++++++-------
 1 file changed, 62 insertions(+), 25 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-mediatek.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-mediatek.c
index cda3f3edde39..b4abc20c8314 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-mediatek.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-mediatek.c
@@ -76,6 +76,8 @@
 struct mac_delay_struct {
 	u32 tx_delay;
 	u32 rx_delay;
+	u32 rgmii_tx_delay;
+	u32 rgmii_rx_delay;
 	bool tx_inv;
 	bool rx_inv;
 };
@@ -103,8 +105,8 @@ struct mediatek_dwmac_variant {
 	const char * const *clk_list;
 	int num_clks;
 
-	u32 rx_delay_max;
-	u32 tx_delay_max;
+	u32 mii_delay_max;
+	u32 rgmii_delay_max;
 	u8 dma_bit_mask;
 };
 
@@ -223,9 +225,9 @@ static int mt2712_set_delay(struct mediatek_dwmac_plat_data *plat)
 	case PHY_INTERFACE_MODE_RGMII_TXID:
 	case PHY_INTERFACE_MODE_RGMII_RXID:
 	case PHY_INTERFACE_MODE_RGMII_ID:
-		rx_delay_stage_val = mac_delay->rx_delay
+		rx_delay_stage_val = mac_delay->rgmii_rx_delay
 				     / MT2712_RGMII_DLY_STAGE_DIV;
-		tx_delay_stage_val = mac_delay->tx_delay
+		tx_delay_stage_val = mac_delay->rgmii_tx_delay
 				     / MT2712_RGMII_DLY_STAGE_DIV;
 
 		fine_val = ETH_FINE_DLY_GTXC | ETH_FINE_DLY_RXC;
@@ -257,8 +259,8 @@ static const struct mediatek_dwmac_variant mt2712_gmac_variant = {
 	.dwmac_set_delay = mt2712_set_delay,
 	.clk_list = mt2712_dwmac_clk_l,
 	.num_clks = ARRAY_SIZE(mt2712_dwmac_clk_l),
-	.rx_delay_max = MT2712_MII_DELAY_MAX,
-	.tx_delay_max = MT2712_MII_DELAY_MAX,
+	.mii_delay_max = MT2712_MII_DELAY_MAX,
+	.rgmii_delay_max = MT2712_RGMII_DELAY_MAX,
 	.dma_bit_mask = 33,
 };
 
@@ -370,9 +372,9 @@ static int mt8195_set_delay(struct mediatek_dwmac_plat_data *plat)
 	case PHY_INTERFACE_MODE_RGMII_TXID:
 	case PHY_INTERFACE_MODE_RGMII_RXID:
 	case PHY_INTERFACE_MODE_RGMII_ID:
-		rx_delay_stage_val = mac_delay->rx_delay
+		rx_delay_stage_val = mac_delay->rgmii_rx_delay
 				     / MT8195_RGMII_DLY_STAGE_DIV;
-		tx_delay_stage_val = mac_delay->tx_delay
+		tx_delay_stage_val = mac_delay->rgmii_tx_delay
 				     / MT8195_RGMII_DLY_STAGE_DIV;
 
 		gtxc_delay_val |= FIELD_PREP(MT8195_DLY_GTXC_ENABLE,
@@ -411,15 +413,18 @@ static const struct mediatek_dwmac_variant mt8195_gmac_variant = {
 	.dwmac_set_delay = mt8195_set_delay,
 	.clk_list = mt8195_dwmac_clk_l,
 	.num_clks = ARRAY_SIZE(mt8195_dwmac_clk_l),
-	.rx_delay_max = MT8195_MII_DELAY_MAX,
-	.tx_delay_max = MT8195_MII_DELAY_MAX,
+	.mii_delay_max = MT8195_MII_DELAY_MAX,
+	.rgmii_delay_max = MT8195_RGMII_DELAY_MAX,
 	.dma_bit_mask = 35,
 };
 
 static int mediatek_dwmac_config_dt(struct mediatek_dwmac_plat_data *plat)
 {
 	struct mac_delay_struct *mac_delay = &plat->mac_delay;
-	u32 tx_delay_ps, rx_delay_ps;
+	u32 rgmii_tx_delay_ps = 0;
+	u32 rgmii_rx_delay_ps = 0;
+	u32 tx_delay_ps = 0;
+	u32 rx_delay_ps = 0;
 
 	plat->peri_regmap = syscon_regmap_lookup_by_phandle(plat->np, "mediatek,pericfg");
 	if (IS_ERR(plat->peri_regmap)) {
@@ -427,24 +432,56 @@ static int mediatek_dwmac_config_dt(struct mediatek_dwmac_plat_data *plat)
 		return PTR_ERR(plat->peri_regmap);
 	}
 
-	if (!of_property_read_u32(plat->np, "mediatek,tx-delay-ps", &tx_delay_ps)) {
-		if (tx_delay_ps < plat->variant->tx_delay_max) {
-			mac_delay->tx_delay = tx_delay_ps;
-		} else {
-			dev_err(plat->dev, "Invalid TX clock delay: %dps\n", tx_delay_ps);
-			return -EINVAL;
-		}
+	of_property_read_u32(plat->np, "mediatek,tx-delay-ps", &tx_delay_ps);
+	if (tx_delay_ps >= plat->variant->mii_delay_max) {
+		dev_err(plat->dev, "Invalid TX clock delay: %dps\n",
+			tx_delay_ps);
+		return -EINVAL;
 	}
 
-	if (!of_property_read_u32(plat->np, "mediatek,rx-delay-ps", &rx_delay_ps)) {
-		if (rx_delay_ps < plat->variant->rx_delay_max) {
-			mac_delay->rx_delay = rx_delay_ps;
-		} else {
-			dev_err(plat->dev, "Invalid RX clock delay: %dps\n", rx_delay_ps);
-			return -EINVAL;
-		}
+	/* Read RGMII TX internal delay standard property */
+	if (of_property_read_u32(plat->np, "tx-internal-delay-ps",
+				 &rgmii_tx_delay_ps)) {
+		/*
+		 * standard property value not available, fallback on vendor
+		 * value instead
+		 */
+		rgmii_tx_delay_ps = tx_delay_ps;
+	}
+
+	if (rgmii_tx_delay_ps >= plat->variant->rgmii_delay_max) {
+		dev_err(plat->dev, "Invalid RGMII TX clock delay: %dps\n",
+			rgmii_tx_delay_ps);
+		return -EINVAL;
+	}
+
+	of_property_read_u32(plat->np, "mediatek,rx-delay-ps", &rx_delay_ps);
+	if (rx_delay_ps >= plat->variant->mii_delay_max) {
+		dev_err(plat->dev, "Invalid RX clock delay: %dps\n",
+			rx_delay_ps);
+		return -EINVAL;
+	}
+
+	/* Read RGMII RX internal delay standard property */
+	if (of_property_read_u32(plat->np, "rx-internal-delay-ps",
+				 &rgmii_rx_delay_ps)) {
+		/*
+		 * standard property value not available, fallback on vendor
+		 * value instead
+		 */
+		rgmii_rx_delay_ps = rx_delay_ps;
+	}
+
+	if (rgmii_rx_delay_ps >= plat->variant->rgmii_delay_max) {
+		dev_err(plat->dev, "Invalid RGMII RX clock delay: %dps\n",
+			rgmii_tx_delay_ps);
+		return -EINVAL;
 	}
 
+	mac_delay->rx_delay = rx_delay_ps;
+	mac_delay->tx_delay = tx_delay_ps;
+	mac_delay->rgmii_tx_delay = rgmii_tx_delay_ps;
+	mac_delay->rgmii_rx_delay = rgmii_rx_delay_ps;
 	mac_delay->tx_inv = of_property_read_bool(plat->np, "mediatek,txc-inverse");
 	mac_delay->rx_inv = of_property_read_bool(plat->np, "mediatek,rxc-inverse");
 	plat->rmii_rxc = of_property_read_bool(plat->np, "mediatek,rmii-rxc");

-- 
2.56.0