Re: [PATCH net-next v12 2/5] net: ti: prueth: Adds ICSSM Ethernet driver

[Bastien Curutchet <bastien.curutchet@bootlin.com>]

Hi Parvathi,

On 7/24/25 9:23 AM, Parvathi Pudi wrote:
> From: Roger Quadros <rogerq@ti.com>
> 
> Updates Kernel configuration to enable PRUETH driver and its dependencies
> along with makefile changes to add the new PRUETH driver.
> 
> Changes includes init and deinit of ICSSM PRU Ethernet driver including
> net dev registration and firmware loading for DUAL-MAC mode running on
> PRU-ICSS2 instance.
> 
> Changes also includes link handling, PRU booting, default firmware loading
> and PRU stopping using existing remoteproc driver APIs.
> 
> Signed-off-by: Roger Quadros <rogerq@ti.com>
> Signed-off-by: Andrew F. Davis <afd@ti.com>
> Signed-off-by: Basharath Hussain Khaja <basharath@couthit.com>
> Signed-off-by: Parvathi Pudi <parvathi@couthit.com>
> ---
>   drivers/net/ethernet/ti/Kconfig              |  12 +
>   drivers/net/ethernet/ti/Makefile             |   3 +
>   drivers/net/ethernet/ti/icssm/icssm_prueth.c | 610 +++++++++++++++++++
>   drivers/net/ethernet/ti/icssm/icssm_prueth.h | 100 +++
>   4 files changed, 725 insertions(+)
>   create mode 100644 drivers/net/ethernet/ti/icssm/icssm_prueth.c
>   create mode 100644 drivers/net/ethernet/ti/icssm/icssm_prueth.h
> 
> diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig
> index a07c910c497a..ab20f22524cb 100644
> --- a/drivers/net/ethernet/ti/Kconfig
> +++ b/drivers/net/ethernet/ti/Kconfig
> @@ -229,4 +229,16 @@ config TI_ICSS_IEP
>   	  To compile this driver as a module, choose M here. The module
>   	  will be called icss_iep.
>   
> +config TI_PRUETH
> +	tristate "TI PRU Ethernet EMAC driver"
> +	depends on PRU_REMOTEPROC
> +	depends on NET_SWITCHDEV
> +	select TI_ICSS_IEP
> +	imply PTP_1588_CLOCK
> +	help
> +	  Some TI SoCs has Programmable Realtime Units (PRUs) cores which can
> +	  support Single or Dual Ethernet ports with help of firmware code running
> +	  on PRU cores. This driver supports remoteproc based communication to
> +	  PRU firmware to expose ethernet interface to Linux.
> +
>   endif # NET_VENDOR_TI
> diff --git a/drivers/net/ethernet/ti/Makefile b/drivers/net/ethernet/ti/Makefile
> index cbcf44806924..93c0a4d0e33a 100644
> --- a/drivers/net/ethernet/ti/Makefile
> +++ b/drivers/net/ethernet/ti/Makefile
> @@ -3,6 +3,9 @@
>   # Makefile for the TI network device drivers.
>   #
>   
> +obj-$(CONFIG_TI_PRUETH) += icssm-prueth.o
> +icssm-prueth-y := icssm/icssm_prueth.o
> +
>   obj-$(CONFIG_TI_CPSW) += cpsw-common.o
>   obj-$(CONFIG_TI_DAVINCI_EMAC) += cpsw-common.o
>   obj-$(CONFIG_TI_CPSW_SWITCHDEV) += cpsw-common.o
> diff --git a/drivers/net/ethernet/ti/icssm/icssm_prueth.c b/drivers/net/ethernet/ti/icssm/icssm_prueth.c
> new file mode 100644
> index 000000000000..375fd636684d
> --- /dev/null
> +++ b/drivers/net/ethernet/ti/icssm/icssm_prueth.c
> @@ -0,0 +1,610 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +/* Texas Instruments ICSSM Ethernet Driver
> + *
> + * Copyright (C) 2018-2022 Texas Instruments Incorporated - https://www.ti.com/
> + *
> + */
> +
> +#include <linux/etherdevice.h>
> +#include <linux/genalloc.h>
> +#include <linux/if_bridge.h>
> +#include <linux/if_hsr.h>
> +#include <linux/if_vlan.h>
> +#include <linux/interrupt.h>
> +#include <linux/kernel.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/module.h>
> +#include <linux/net_tstamp.h>
> +#include <linux/of.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_mdio.h>
> +#include <linux/of_net.h>
> +#include <linux/platform_device.h>
> +#include <linux/phy.h>
> +#include <linux/remoteproc/pruss.h>
> +#include <linux/ptp_classify.h>
> +#include <linux/regmap.h>
> +#include <linux/remoteproc.h>
> +#include <net/pkt_cls.h>
> +
> +#include "icssm_prueth.h"
> +
> +/* called back by PHY layer if there is change in link state of hw port*/
> +static void icssm_emac_adjust_link(struct net_device *ndev)
> +{
> +	struct prueth_emac *emac = netdev_priv(ndev);
> +	struct phy_device *phydev = emac->phydev;
> +	bool new_state = false;
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&emac->lock, flags);
> +
> +	if (phydev->link) {
> +		/* check the mode of operation */
> +		if (phydev->duplex != emac->duplex) {
> +			new_state = true;
> +			emac->duplex = phydev->duplex;
> +		}
> +		if (phydev->speed != emac->speed) {
> +			new_state = true;
> +			emac->speed = phydev->speed;
> +		}
> +		if (!emac->link) {
> +			new_state = true;
> +			emac->link = 1;
> +		}
> +	} else if (emac->link) {
> +		new_state = true;
> +		emac->link = 0;
> +	}
> +
> +	if (new_state)
> +		phy_print_status(phydev);
> +
> +	if (emac->link) {
> +	       /* reactivate the transmit queue if it is stopped */
> +		if (netif_running(ndev) && netif_queue_stopped(ndev))
> +			netif_wake_queue(ndev);
> +	} else {
> +		if (!netif_queue_stopped(ndev))
> +			netif_stop_queue(ndev);
> +	}
> +
> +	spin_unlock_irqrestore(&emac->lock, flags);
> +}
> +
> +static int icssm_emac_set_boot_pru(struct prueth_emac *emac,
> +				   struct net_device *ndev)
> +{
> +	const struct prueth_firmware *pru_firmwares;
> +	struct prueth *prueth = emac->prueth;
> +	const char *fw_name;
> +	int ret;
> +
> +	pru_firmwares = &prueth->fw_data->fw_pru[emac->port_id - 1];
> +	fw_name = pru_firmwares->fw_name[prueth->eth_type];
> +	if (!fw_name) {
> +		netdev_err(ndev, "eth_type %d not supported\n",
> +			   prueth->eth_type);
> +		return -ENODEV;
> +	}
> +
> +	ret = rproc_set_firmware(emac->pru, fw_name);
> +	if (ret) {
> +		netdev_err(ndev, "failed to set PRU0 firmware %s: %d\n",
> +			   fw_name, ret);
> +		return ret;
> +	}
> +
> +	ret = rproc_boot(emac->pru);
> +	if (ret) {
> +		netdev_err(ndev, "failed to boot PRU0: %d\n", ret);
> +		return ret;
> +	}
> +
> +	return ret;
> +}
> +
> +/**
> + * icssm_emac_ndo_open - EMAC device open
> + * @ndev: network adapter device
> + *
> + * Called when system wants to start the interface.
> + *
> + * Return: 0 for a successful open, or appropriate error code
> + */
> +static int icssm_emac_ndo_open(struct net_device *ndev)
> +{
> +	struct prueth_emac *emac = netdev_priv(ndev);
> +	int ret;
> +
> +	ret = icssm_emac_set_boot_pru(emac, ndev);
> +	if (ret)
> +		return ret;
> +
> +	/* start PHY */
> +	phy_start(emac->phydev);
> +
> +	return 0;
> +}
> +
> +/**
> + * icssm_emac_ndo_stop - EMAC device stop
> + * @ndev: network adapter device
> + *
> + * Called when system wants to stop or down the interface.
> + *
> + * Return: Always 0 (Success)
> + */
> +static int icssm_emac_ndo_stop(struct net_device *ndev)
> +{
> +	struct prueth_emac *emac = netdev_priv(ndev);
> +
> +	/* stop PHY */
> +	phy_stop(emac->phydev);
> +
> +	rproc_shutdown(emac->pru);
> +
> +	return 0;
> +}
> +
> +static const struct net_device_ops emac_netdev_ops = {
> +	.ndo_open = icssm_emac_ndo_open,
> +	.ndo_stop = icssm_emac_ndo_stop,
> +};
> +
> +/* get emac_port corresponding to eth_node name */
> +static int icssm_prueth_node_port(struct device_node *eth_node)
> +{
> +	u32 port_id;
> +	int ret;
> +
> +	ret = of_property_read_u32(eth_node, "reg", &port_id);
> +	if (ret)
> +		return ret;
> +
> +	if (port_id == 0)
> +		return PRUETH_PORT_MII0;
> +	else if (port_id == 1)
> +		return PRUETH_PORT_MII1;
> +	else
> +		return PRUETH_PORT_INVALID;
> +}
> +
> +/* get MAC instance corresponding to eth_node name */
> +static int icssm_prueth_node_mac(struct device_node *eth_node)
> +{
> +	u32 port_id;
> +	int ret;
> +
> +	ret = of_property_read_u32(eth_node, "reg", &port_id);
> +	if (ret)
> +		return ret;
> +
> +	if (port_id == 0)
> +		return PRUETH_MAC0;
> +	else if (port_id == 1)
> +		return PRUETH_MAC1;
> +	else
> +		return PRUETH_MAC_INVALID;
> +}
> +
> +static int icssm_prueth_netdev_init(struct prueth *prueth,
> +				    struct device_node *eth_node)
> +{
> +	struct prueth_emac *emac;
> +	struct net_device *ndev;
> +	enum prueth_port port;
> +	enum prueth_mac mac;
> +	int ret;
> +
> +	port = icssm_prueth_node_port(eth_node);
> +	if (port == PRUETH_PORT_INVALID)
> +		return -EINVAL;
> +
> +	mac = icssm_prueth_node_mac(eth_node);
> +	if (mac == PRUETH_MAC_INVALID)
> +		return -EINVAL;
> +
> +	ndev = devm_alloc_etherdev(prueth->dev, sizeof(*emac));
> +	if (!ndev)
> +		return -ENOMEM;
> +
> +	SET_NETDEV_DEV(ndev, prueth->dev);
> +	emac = netdev_priv(ndev);
> +	prueth->emac[mac] = emac;
> +	emac->prueth = prueth;
> +	emac->ndev = ndev;
> +	emac->port_id = port;
> +
> +	/* by default eth_type is EMAC */
> +	switch (port) {
> +	case PRUETH_PORT_MII0:
> +		emac->pru = prueth->pru0;
> +		break;
> +	case PRUETH_PORT_MII1:
> +		emac->pru = prueth->pru1;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +	/* get mac address from DT and set private and netdev addr */
> +	ret = of_get_ethdev_address(eth_node, ndev);
> +	if (!is_valid_ether_addr(ndev->dev_addr)) {
> +		eth_hw_addr_random(ndev);
> +		dev_warn(prueth->dev, "port %d: using random MAC addr: %pM\n",
> +			 port, ndev->dev_addr);
> +	}
> +	ether_addr_copy(emac->mac_addr, ndev->dev_addr);
> +
> +	/* connect PHY */
> +	emac->phydev = of_phy_get_and_connect(ndev, eth_node,
> +					      icssm_emac_adjust_link);
> +	if (!emac->phydev) {
> +		dev_dbg(prueth->dev, "PHY connection failed\n");
> +		ret = -EPROBE_DEFER;
> +		goto free;
> +	}
> +
> +	/* remove unsupported modes */
> +	phy_remove_link_mode(emac->phydev, ETHTOOL_LINK_MODE_10baseT_Full_BIT);
> +
> +	phy_remove_link_mode(emac->phydev, ETHTOOL_LINK_MODE_10baseT_Half_BIT);
> +	phy_remove_link_mode(emac->phydev, ETHTOOL_LINK_MODE_100baseT_Half_BIT);
> +
> +	phy_remove_link_mode(emac->phydev, ETHTOOL_LINK_MODE_Pause_BIT);
> +	phy_remove_link_mode(emac->phydev, ETHTOOL_LINK_MODE_Asym_Pause_BIT);
> +
> +	ndev->netdev_ops = &emac_netdev_ops;
> +

I think ndev->dev.of_node should be set to eth_node here.

If ndev->dev.of_node isn't set, of_find_net_device_by_node() won't find 
the iccsm_prueth ports and their of_node won't be available in sysfs 
(which, in my case, leads to issues during the probe of a switch 
connected to them)


Kind regards,
Bastien