Merge branch 'net-lan969x-add-rgmii-support'

Daniel Machon says:

====================
net: lan969x: add RGMII support

== Description:

This series is the fourth of a multi-part series, that prepares and adds
support for the new lan969x switch driver.

The upstreaming efforts is split into multiple series (might change a
bit as we go along):

        1) Prepare the Sparx5 driver for lan969x (merged)

        2) Add support for lan969x (same basic features as Sparx5
           provides excl. FDMA and VCAP, merged).

        3) Add lan969x VCAP functionality (merged).

    --> 4) Add RGMII support.

        5) Add FDMA support.

== RGMII support:

The lan969x switch device includes two RGMII port interfaces (port 28
and 29) supporting data speeds of 1 Gbps, 100 Mbps and 10 Mbps.

== Patch breakdown:

Patch #1 does some preparation work.

Patch #2 adds new function: is_port_rgmii() to the match data ops.

Patch #3 uses the is_port_rgmii() in a number of places.

Patch #4 makes sure that we do not configure an RGMII device as a
         low-speed device, when doing a port config.

Patch #5 makes sure we only return the PCS if the port mode requires
         it.

Patch #6 adds checks for RGMII PHY modes in sparx5_verify_speeds().

Patch #7 adds registers required to configure RGMII.

Patch #8 adds RGMII implementation.

Patch #9 documents RGMII delays in the dt-bindings.

Details are in the commit description of the individual patches

v4: https://lore.kernel.org/20241213-sparx5-lan969x-switch-driver-4-v4-0-d1a72c9c4714@microchip.com
v3: https://lore.kernel.org/20241118-sparx5-lan969x-switch-driver-4-v3-0-3cefee5e7e3a@microchip.com
v2: https://lore.kernel.org/20241113-sparx5-lan969x-switch-driver-4-v2-0-0db98ac096d1@microchip.com
v1: https://lore.kernel.org/20241106-sparx5-lan969x-switch-driver-4-v1-0-f7f7316436bd@microchip.com
====================

Link: https://patch.msgid.link/20241220-sparx5-lan969x-switch-driver-4-v5-0-fa8ba5dff732@microchip.com
Signed-off-by: Jakub Kicinski <[email protected]>

Author: kuba-moo

Documentation/devicetree/bindings/net/microchip,sparx5-switch.yaml

@@ -129,6 +129,24 @@ properties:
             minimum: 0
             maximum: 383
 
+          rx-internal-delay-ps:
+            description:
+              RGMII Receive Clock Delay defined in pico seconds, used to select
+              the DLL phase shift between 1000 ps (45 degree shift at 1Gbps) and
+              3300 ps (147 degree shift at 1Gbps). A value of 0 ps will disable
+              any delay. The Default is no delay.
+            enum: [0, 1000, 1700, 2000, 2500, 3000, 3300]
+            default: 0
+
+          tx-internal-delay-ps:
+            description:
+              RGMII Transmit Clock Delay defined in pico seconds, used to select
+              the DLL phase shift between 1000 ps (45 degree shift at 1Gbps) and
+              3300 ps (147 degree shift at 1Gbps). A value of 0 ps will disable
+              any delay. The Default is no delay.
+            enum: [0, 1000, 1700, 2000, 2500, 3000, 3300]
+            default: 0
+
         required:
           - reg
           - phys

drivers/net/ethernet/microchip/sparx5/Makefile

@@ -20,7 +20,8 @@ sparx5-switch-$(CONFIG_LAN969X_SWITCH) += lan969x/lan969x_regs.o \
 					  lan969x/lan969x.o \
 					  lan969x/lan969x_calendar.o \
 					  lan969x/lan969x_vcap_ag_api.o \
-					  lan969x/lan969x_vcap_impl.o
+					  lan969x/lan969x_vcap_impl.o \
+					  lan969x/lan969x_rgmii.o
 
 # Provide include files
 ccflags-y += -I$(srctree)/drivers/net/ethernet/microchip/vcap

drivers/net/ethernet/microchip/sparx5/lan969x/lan969x.c

@@ -90,9 +90,12 @@ static const struct sparx5_main_io_resource lan969x_main_iomap[] =  {
 	{ TARGET_DEV2G5 + 27,         0x30d8000, 1 }, /* 0xe30d8000 */
 	{ TARGET_DEV10G +  9,         0x30dc000, 1 }, /* 0xe30dc000 */
 	{ TARGET_PCS10G_BR +  9,      0x30e0000, 1 }, /* 0xe30e0000 */
+	{ TARGET_DEVRGMII,            0x30e4000, 1 }, /* 0xe30e4000 */
+	{ TARGET_DEVRGMII +  1,       0x30e8000, 1 }, /* 0xe30e8000 */
 	{ TARGET_DSM,                 0x30ec000, 1 }, /* 0xe30ec000 */
 	{ TARGET_PORT_CONF,           0x30f0000, 1 }, /* 0xe30f0000 */
 	{ TARGET_ASM,                 0x3200000, 1 }, /* 0xe3200000 */
+	{ TARGET_HSIO_WRAP,           0x3408000, 1 }, /* 0xe3408000 */
 };
 
 static struct sparx5_sdlb_group lan969x_sdlb_groups[LAN969X_SDLB_GRP_CNT] = {
@@ -329,13 +332,15 @@ static const struct sparx5_ops lan969x_ops = {
 	.is_port_5g              = &lan969x_port_is_5g,
 	.is_port_10g             = &lan969x_port_is_10g,
 	.is_port_25g             = &lan969x_port_is_25g,
+	.is_port_rgmii           = &lan969x_port_is_rgmii,
 	.get_port_dev_index      = &lan969x_port_dev_mapping,
 	.get_port_dev_bit        = &lan969x_get_dev_mode_bit,
 	.get_hsch_max_group_rate = &lan969x_get_hsch_max_group_rate,
 	.get_sdlb_group          = &lan969x_get_sdlb_group,
 	.set_port_mux            = &lan969x_port_mux_set,
 	.ptp_irq_handler         = &lan969x_ptp_irq_handler,
 	.dsm_calendar_calc       = &lan969x_dsm_calendar_calc,
+	.port_config_rgmii       = &lan969x_port_config_rgmii,
 };
 
 const struct sparx5_match_data lan969x_desc = {

drivers/net/ethernet/microchip/sparx5/lan969x/lan969x.h

@@ -59,7 +59,17 @@ static inline bool lan969x_port_is_25g(int portno)
 	return false;
 }
 
+static inline bool lan969x_port_is_rgmii(int portno)
+{
+	return portno == 28 || portno == 29;
+}
+
 /* lan969x_calendar.c */
 int lan969x_dsm_calendar_calc(struct sparx5 *sparx5, u32 taxi,
 			      struct sparx5_calendar_data *data);
+
+/* lan969x_rgmii.c */
+int lan969x_port_config_rgmii(struct sparx5_port *port,
+			      struct sparx5_port_config *conf);
+
 #endif

drivers/net/ethernet/microchip/sparx5/lan969x/lan969x_rgmii.c

@@ -0,0 +1,224 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* Microchip lan969x Switch driver
+ *
+ * Copyright (c) 2024 Microchip Technology Inc. and its subsidiaries.
+ */
+
+#include "lan969x.h"
+
+/* Tx clock selectors */
+#define LAN969X_RGMII_TX_CLK_SEL_125MHZ 1  /* 1000Mbps */
+#define LAN969X_RGMII_TX_CLK_SEL_25MHZ  2  /* 100Mbps */
+#define LAN969X_RGMII_TX_CLK_SEL_2M5MHZ 3  /* 10Mbps */
+
+/* Port speed selectors */
+#define LAN969X_RGMII_SPEED_SEL_10 0   /* Select 10Mbps speed */
+#define LAN969X_RGMII_SPEED_SEL_100 1  /* Select 100Mbps speed */
+#define LAN969X_RGMII_SPEED_SEL_1000 2 /* Select 1000Mbps speed */
+
+/* Clock delay selectors */
+#define LAN969X_RGMII_CLK_DELAY_SEL_1_0_NS 2  /* Phase shift 45deg */
+#define LAN969X_RGMII_CLK_DELAY_SEL_1_7_NS 3  /* Phase shift 77deg */
+#define LAN969X_RGMII_CLK_DELAY_SEL_2_0_NS 4  /* Phase shift 90deg */
+#define LAN969X_RGMII_CLK_DELAY_SEL_2_5_NS 5  /* Phase shift 112deg */
+#define LAN969X_RGMII_CLK_DELAY_SEL_3_0_NS 6  /* Phase shift 135deg */
+#define LAN969X_RGMII_CLK_DELAY_SEL_3_3_NS 7  /* Phase shift 147deg */
+
+#define LAN969X_RGMII_PORT_START_IDX 28 /* Index of the first RGMII port */
+#define LAN969X_RGMII_IFG_TX 4          /* TX Inter Frame Gap value */
+#define LAN969X_RGMII_IFG_RX1 5         /* RX1 Inter Frame Gap value */
+#define LAN969X_RGMII_IFG_RX2 1         /* RX2 Inter Frame Gap value */
+
+#define RGMII_PORT_IDX(port) ((port)->portno - LAN969X_RGMII_PORT_START_IDX)
+
+/* Get the tx clock selector based on the port speed. */
+static int lan969x_rgmii_get_clk_sel(int speed)
+{
+	return (speed == SPEED_10  ? LAN969X_RGMII_TX_CLK_SEL_2M5MHZ :
+		speed == SPEED_100 ? LAN969X_RGMII_TX_CLK_SEL_25MHZ :
+				     LAN969X_RGMII_TX_CLK_SEL_125MHZ);
+}
+
+/* Get the port speed selector based on the port speed. */
+static int lan969x_rgmii_get_speed_sel(int speed)
+{
+	return (speed == SPEED_10  ? LAN969X_RGMII_SPEED_SEL_10 :
+		speed == SPEED_100 ? LAN969X_RGMII_SPEED_SEL_100 :
+				     LAN969X_RGMII_SPEED_SEL_1000);
+}
+
+/* Get the clock delay selector based on the clock delay in picoseconds. */
+static int lan969x_rgmii_get_clk_delay_sel(struct sparx5_port *port,
+					   u32 delay_ps, u32 *clk_delay_sel)
+{
+	switch (delay_ps) {
+	case 0:
+		/* Hardware default selector. */
+		*clk_delay_sel = LAN969X_RGMII_CLK_DELAY_SEL_2_5_NS;
+		break;
+	case 1000:
+		*clk_delay_sel = LAN969X_RGMII_CLK_DELAY_SEL_1_0_NS;
+		break;
+	case 1700:
+		*clk_delay_sel = LAN969X_RGMII_CLK_DELAY_SEL_1_7_NS;
+		break;
+	case 2000:
+		*clk_delay_sel = LAN969X_RGMII_CLK_DELAY_SEL_2_0_NS;
+		break;
+	case 2500:
+		*clk_delay_sel = LAN969X_RGMII_CLK_DELAY_SEL_2_5_NS;
+		break;
+	case 3000:
+		*clk_delay_sel = LAN969X_RGMII_CLK_DELAY_SEL_3_0_NS;
+		break;
+	case 3300:
+		*clk_delay_sel = LAN969X_RGMII_CLK_DELAY_SEL_3_3_NS;
+		break;
+	default:
+		dev_err(port->sparx5->dev, "Invalid RGMII delay: %u", delay_ps);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/* Configure the RGMII tx clock frequency. */
+static void lan969x_rgmii_tx_clk_config(struct sparx5_port *port,
+					struct sparx5_port_config *conf)
+{
+	u32 clk_sel = lan969x_rgmii_get_clk_sel(conf->speed);
+	u32 idx = RGMII_PORT_IDX(port);
+
+	/* Take the RGMII clock domain out of reset and set tx clock
+	 * frequency.
+	 */
+	spx5_rmw(HSIO_WRAP_RGMII_CFG_TX_CLK_CFG_SET(clk_sel) |
+		 HSIO_WRAP_RGMII_CFG_RGMII_TX_RST_SET(0) |
+		 HSIO_WRAP_RGMII_CFG_RGMII_RX_RST_SET(0),
+		 HSIO_WRAP_RGMII_CFG_TX_CLK_CFG |
+		 HSIO_WRAP_RGMII_CFG_RGMII_TX_RST |
+		 HSIO_WRAP_RGMII_CFG_RGMII_RX_RST,
+		 port->sparx5, HSIO_WRAP_RGMII_CFG(idx));
+}
+
+/* Configure the RGMII port device. */
+static void lan969x_rgmii_port_device_config(struct sparx5_port *port,
+					     struct sparx5_port_config *conf)
+{
+	u32 dtag, dotag, etype, speed_sel, idx = RGMII_PORT_IDX(port);
+
+	speed_sel = lan969x_rgmii_get_speed_sel(conf->speed);
+
+	etype = (port->vlan_type == SPX5_VLAN_PORT_TYPE_S_CUSTOM ?
+		 port->custom_etype :
+		 port->vlan_type == SPX5_VLAN_PORT_TYPE_C ?
+		 ETH_P_8021Q : ETH_P_8021AD);
+
+	dtag = port->max_vlan_tags == SPX5_PORT_MAX_TAGS_TWO;
+	dotag = port->max_vlan_tags != SPX5_PORT_MAX_TAGS_NONE;
+
+	/* Enable the MAC. */
+	spx5_wr(DEVRGMII_MAC_ENA_CFG_RX_ENA_SET(1) |
+		DEVRGMII_MAC_ENA_CFG_TX_ENA_SET(1),
+		port->sparx5, DEVRGMII_MAC_ENA_CFG(idx));
+
+	/* Configure the Inter Frame Gap. */
+	spx5_wr(DEVRGMII_MAC_IFG_CFG_TX_IFG_SET(LAN969X_RGMII_IFG_TX) |
+		DEVRGMII_MAC_IFG_CFG_RX_IFG1_SET(LAN969X_RGMII_IFG_RX1) |
+		DEVRGMII_MAC_IFG_CFG_RX_IFG2_SET(LAN969X_RGMII_IFG_RX2),
+		port->sparx5, DEVRGMII_MAC_IFG_CFG(idx));
+
+	/* Configure port data rate. */
+	spx5_wr(DEVRGMII_DEV_RST_CTRL_SPEED_SEL_SET(speed_sel),
+		port->sparx5, DEVRGMII_DEV_RST_CTRL(idx));
+
+	/* Configure VLAN awareness. */
+	spx5_wr(DEVRGMII_MAC_TAGS_CFG_TAG_ID_SET(etype) |
+		DEVRGMII_MAC_TAGS_CFG_PB_ENA_SET(dtag) |
+		DEVRGMII_MAC_TAGS_CFG_VLAN_AWR_ENA_SET(dotag) |
+		DEVRGMII_MAC_TAGS_CFG_VLAN_LEN_AWR_ENA_SET(dotag),
+		port->sparx5,
+		DEVRGMII_MAC_TAGS_CFG(idx));
+}
+
+/* Configure the RGMII delay lines in the MAC.
+ *
+ * We use the rx-internal-delay-ps" and "tx-internal-delay-ps" properties to
+ * configure the rx and tx delays for the MAC. If these properties are missing
+ * or set to zero, the MAC will not apply any delay.
+ *
+ * The PHY side delays are determined by the PHY mode
+ * (e.g. PHY_INTERFACE_MODE_RGMII_{ID, RXID, TXID}), and ignored by the MAC side
+ * entirely.
+ */
+static int lan969x_rgmii_delay_config(struct sparx5_port *port,
+				      struct sparx5_port_config *conf)
+{
+	u32 tx_clk_sel, rx_clk_sel, tx_delay_ps = 0, rx_delay_ps = 0;
+	u32 idx = RGMII_PORT_IDX(port);
+	int err;
+
+	of_property_read_u32(port->of_node, "rx-internal-delay-ps",
+			     &rx_delay_ps);
+
+	of_property_read_u32(port->of_node, "tx-internal-delay-ps",
+			     &tx_delay_ps);
+
+	err = lan969x_rgmii_get_clk_delay_sel(port, rx_delay_ps, &rx_clk_sel);
+	if (err)
+		return err;
+
+	err = lan969x_rgmii_get_clk_delay_sel(port, tx_delay_ps, &tx_clk_sel);
+	if (err)
+		return err;
+
+	/* Configure rx delay. */
+	spx5_rmw(HSIO_WRAP_DLL_CFG_DLL_RST_SET(0) |
+		 HSIO_WRAP_DLL_CFG_DLL_ENA_SET(1) |
+		 HSIO_WRAP_DLL_CFG_DLL_CLK_ENA_SET(!!rx_delay_ps) |
+		 HSIO_WRAP_DLL_CFG_DLL_CLK_SEL_SET(rx_clk_sel),
+		 HSIO_WRAP_DLL_CFG_DLL_RST |
+		 HSIO_WRAP_DLL_CFG_DLL_ENA |
+		 HSIO_WRAP_DLL_CFG_DLL_CLK_ENA |
+		 HSIO_WRAP_DLL_CFG_DLL_CLK_SEL,
+		 port->sparx5, HSIO_WRAP_DLL_CFG(idx, 0));
+
+	/* Configure tx delay. */
+	spx5_rmw(HSIO_WRAP_DLL_CFG_DLL_RST_SET(0) |
+		 HSIO_WRAP_DLL_CFG_DLL_ENA_SET(1) |
+		 HSIO_WRAP_DLL_CFG_DLL_CLK_ENA_SET(!!tx_delay_ps) |
+		 HSIO_WRAP_DLL_CFG_DLL_CLK_SEL_SET(tx_clk_sel),
+		 HSIO_WRAP_DLL_CFG_DLL_RST |
+		 HSIO_WRAP_DLL_CFG_DLL_ENA |
+		 HSIO_WRAP_DLL_CFG_DLL_CLK_ENA |
+		 HSIO_WRAP_DLL_CFG_DLL_CLK_SEL,
+		 port->sparx5, HSIO_WRAP_DLL_CFG(idx, 1));
+
+	return 0;
+}
+
+/* Configure GPIO's to be used as RGMII interface. */
+static void lan969x_rgmii_gpio_config(struct sparx5_port *port)
+{
+	u32 idx = RGMII_PORT_IDX(port);
+
+	/* Enable the RGMII on the GPIOs. */
+	spx5_wr(HSIO_WRAP_XMII_CFG_GPIO_XMII_CFG_SET(1), port->sparx5,
+		HSIO_WRAP_XMII_CFG(!idx));
+}
+
+int lan969x_port_config_rgmii(struct sparx5_port *port,
+			      struct sparx5_port_config *conf)
+{
+	int err;
+
+	err = lan969x_rgmii_delay_config(port, conf);
+	if (err)
+		return err;
+
+	lan969x_rgmii_tx_clk_config(port, conf);
+	lan969x_rgmii_gpio_config(port);
+	lan969x_rgmii_port_device_config(port, conf);
+
+	return 0;
+}

drivers/net/ethernet/microchip/sparx5/sparx5_main.c

@@ -313,10 +313,13 @@ static int sparx5_create_port(struct sparx5 *sparx5,
 			      struct initial_port_config *config)
 {
 	struct sparx5_port *spx5_port;
+	const struct sparx5_ops *ops;
 	struct net_device *ndev;
 	struct phylink *phylink;
 	int err;
 
+	ops = sparx5->data->ops;
+
 	ndev = sparx5_create_netdev(sparx5, config->portno);
 	if (IS_ERR(ndev)) {
 		dev_err(sparx5->dev, "Could not create net device: %02u\n",
@@ -357,6 +360,9 @@ static int sparx5_create_port(struct sparx5 *sparx5,
 		MAC_SYM_PAUSE | MAC_10 | MAC_100 | MAC_1000FD |
 		MAC_2500FD | MAC_5000FD | MAC_10000FD | MAC_25000FD;
 
+	if (ops->is_port_rgmii(spx5_port->portno))
+		phy_interface_set_rgmii(spx5_port->phylink_config.supported_interfaces);
+
 	__set_bit(PHY_INTERFACE_MODE_SGMII,
 		  spx5_port->phylink_config.supported_interfaces);
 	__set_bit(PHY_INTERFACE_MODE_QSGMII,
@@ -830,6 +836,7 @@ static int mchp_sparx5_probe(struct platform_device *pdev)
 	struct initial_port_config *configs, *config;
 	struct device_node *np = pdev->dev.of_node;
 	struct device_node *ports, *portnp;
+	const struct sparx5_ops *ops;
 	struct reset_control *reset;
 	struct sparx5 *sparx5;
 	int idx = 0, err = 0;
@@ -851,6 +858,7 @@ static int mchp_sparx5_probe(struct platform_device *pdev)
 		return -EINVAL;
 
 	regs = sparx5->data->regs;
+	ops = sparx5->data->ops;
 
 	/* Do switch core reset if available */
 	reset = devm_reset_control_get_optional_shared(&pdev->dev, "switch");
@@ -880,7 +888,7 @@ static int mchp_sparx5_probe(struct platform_device *pdev)
 
 	for_each_available_child_of_node(ports, portnp) {
 		struct sparx5_port_config *conf;
-		struct phy *serdes;
+		struct phy *serdes = NULL;
 		u32 portno;
 
 		err = of_property_read_u32(portnp, "reg", &portno);
@@ -910,13 +918,17 @@ static int mchp_sparx5_probe(struct platform_device *pdev)
 			conf->sd_sgpio = ~0;
 		else
 			sparx5->sd_sgpio_remapping = true;
-		serdes = devm_of_phy_get(sparx5->dev, portnp, NULL);
-		if (IS_ERR(serdes)) {
-			err = dev_err_probe(sparx5->dev, PTR_ERR(serdes),
-					    "port %u: missing serdes\n",
-					    portno);
-			of_node_put(portnp);
-			goto cleanup_config;
+		/* There is no SerDes node for RGMII ports. */
+		if (!ops->is_port_rgmii(portno)) {
+			serdes = devm_of_phy_get(sparx5->dev, portnp, NULL);
+			if (IS_ERR(serdes)) {
+				err = dev_err_probe(sparx5->dev,
+						    PTR_ERR(serdes),
+						    "port %u: missing serdes\n",
+						    portno);
+				of_node_put(portnp);
+				goto cleanup_config;
+			}
 		}
 		config->portno = portno;
 		config->node = portnp;
@@ -1072,6 +1084,7 @@ static const struct sparx5_ops sparx5_ops = {
 	.is_port_5g              = &sparx5_port_is_5g,
 	.is_port_10g             = &sparx5_port_is_10g,
 	.is_port_25g             = &sparx5_port_is_25g,
+	.is_port_rgmii           = &sparx5_port_is_rgmii,
 	.get_port_dev_index      = &sparx5_port_dev_mapping,
 	.get_port_dev_bit        = &sparx5_port_dev_mapping,
 	.get_hsch_max_group_rate = &sparx5_get_hsch_max_group_rate,