Re: [PATCH v3 net-next 13/15] net: enetc: add PTP synchronization support for ENETC v4

Frank Li
2025-08-12T15:58:42Z

On Tue, Aug 12, 2025 at 05:46:32PM +0800, Wei Fang wrote:
> Regarding PTP, ENETC v4 has some changes compared to ENETC v1 (LS1028A),
> mainly as follows.
>
> 1. ENETC v4 uses a different PTP driver, so the way to get phc_index is
> different from LS1028A. Therefore, enetc_get_ts_info() has been modified
> appropriately to be compatible with ENETC v1 and v4.
>
> 2. The hardware of ENETC v4 does not support "dma-coherent", therefore,
> to support PTP one-step, the PTP sync packets must be modified before
> calling dma_map_single() to map the DMA cache of the packets. Otherwise,
> the modification is invalid, the originTimestamp and correction fields
> of the sent packets will still be the values before the modification.

In patch, I have not find dma_map_single(), is it in enetc_map_tx_buffs()?

This move should be fix, even dma-coherent, it also should be before
dma_map_single(). just hardware dma-coherent hidden the problem.

Frank
>
> 3. The PMa_SINGLE_STEP register has changed in ENETC v4, not only the
> register offset, but also some register fields. Therefore, two helper
> functions are added, enetc_set_one_step_ts() for ENETC v1 and
> enetc4_set_one_step_ts() for ENETC v4.
>
> Signed-off-by: Wei Fang <wei.fang@nxp.com>
>
> ---
> v2 changes:
> 1. Move the definition of enetc_ptp_clock_is_enabled() to resolve build
> errors.
> 2. Add parsing of "nxp,netc-timer" property to get PCIe device of NETC
> Timer.
> v3 changes:
> 1. Change CONFIG_PTP_1588_CLOCK_NETC to CONFIG_PTP_NETC_V4_TIMER
> 2. Change "nxp,netc-timer" to "ptp-timer"
> ---
> drivers/net/ethernet/freescale/enetc/enetc.c | 55 +++++++----
> drivers/net/ethernet/freescale/enetc/enetc.h | 8 ++
> .../net/ethernet/freescale/enetc/enetc4_hw.h | 6 ++
> .../net/ethernet/freescale/enetc/enetc4_pf.c | 3 +
> .../ethernet/freescale/enetc/enetc_ethtool.c | 92 ++++++++++++++++---
> 5 files changed, 135 insertions(+), 29 deletions(-)
>
> diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
> index 4325eb3d9481..6dbc9cc811a0 100644
> --- a/drivers/net/ethernet/freescale/enetc/enetc.c
> +++ b/drivers/net/ethernet/freescale/enetc/enetc.c
> @@ -221,6 +221,31 @@ static void enetc_unwind_tx_frame(struct enetc_bdr *tx_ring, int count, int i)
> }
> }
>
> +static void enetc_set_one_step_ts(struct enetc_si *si, bool udp, int offset)
> +{
> + u32 val = ENETC_PM0_SINGLE_STEP_EN;
> +
> + val |= ENETC_SET_SINGLE_STEP_OFFSET(offset);
> + if (udp)
> + val |= ENETC_PM0_SINGLE_STEP_CH;
> +
> + /* The "Correction" field of a packet is updated based on the
> + * current time and the timestamp provided
> + */
> + enetc_port_mac_wr(si, ENETC_PM0_SINGLE_STEP, val);
> +}
> +
> +static void enetc4_set_one_step_ts(struct enetc_si *si, bool udp, int offset)
> +{
> + u32 val = PM_SINGLE_STEP_EN;
> +
> + val |= PM_SINGLE_STEP_OFFSET_SET(offset);
> + if (udp)
> + val |= PM_SINGLE_STEP_CH;
> +
> + enetc_port_mac_wr(si, ENETC4_PM_SINGLE_STEP(0), val);
> +}
> +
> static u32 enetc_update_ptp_sync_msg(struct enetc_ndev_priv *priv,
> struct sk_buff *skb)
> {
> @@ -234,7 +259,6 @@ static u32 enetc_update_ptp_sync_msg(struct enetc_ndev_priv *priv,
> u32 lo, hi, nsec;
> u8 *data;
> u64 sec;
> - u32 val;
>
> lo = enetc_rd_hot(hw, ENETC_SICTR0);
> hi = enetc_rd_hot(hw, ENETC_SICTR1);
> @@ -279,12 +303,10 @@ static u32 enetc_update_ptp_sync_msg(struct enetc_ndev_priv *priv,
> *(__be32 *)(data + tstamp_off + 6) = new_nsec;
>
> /* Configure single-step register */
> - val = ENETC_PM0_SINGLE_STEP_EN;
> - val |= ENETC_SET_SINGLE_STEP_OFFSET(corr_off);
> - if (enetc_cb->udp)
> - val |= ENETC_PM0_SINGLE_STEP_CH;
> -
> - enetc_port_mac_wr(priv->si, ENETC_PM0_SINGLE_STEP, val);
> + if (is_enetc_rev1(si))
> + enetc_set_one_step_ts(si, enetc_cb->udp, corr_off);
> + else
> + enetc4_set_one_step_ts(si, enetc_cb->udp, corr_off);
>
> return lo & ENETC_TXBD_TSTAMP;
> }
> @@ -303,6 +325,7 @@ static int enetc_map_tx_buffs(struct enetc_bdr *tx_ring, struct sk_buff *skb)
> unsigned int f;
> dma_addr_t dma;
> u8 flags = 0;
> + u32 tstamp;
>
> enetc_clear_tx_bd(&temp_bd);
> if (skb->ip_summed == CHECKSUM_PARTIAL) {
> @@ -327,6 +350,13 @@ static int enetc_map_tx_buffs(struct enetc_bdr *tx_ring, struct sk_buff *skb)
> }
> }
>
> + if (enetc_cb->flag & ENETC_F_TX_ONESTEP_SYNC_TSTAMP) {
> + do_onestep_tstamp = true;
> + tstamp = enetc_update_ptp_sync_msg(priv, skb);
> + } else if (enetc_cb->flag & ENETC_F_TX_TSTAMP) {
> + do_twostep_tstamp = true;
> + }
> +
> i = tx_ring->next_to_use;
> txbd = ENETC_TXBD(*tx_ring, i);
> prefetchw(txbd);
> @@ -346,11 +376,6 @@ static int enetc_map_tx_buffs(struct enetc_bdr *tx_ring, struct sk_buff *skb)
> count++;
>
> do_vlan = skb_vlan_tag_present(skb);
> - if (enetc_cb->flag & ENETC_F_TX_ONESTEP_SYNC_TSTAMP)
> - do_onestep_tstamp = true;
> - else if (enetc_cb->flag & ENETC_F_TX_TSTAMP)
> - do_twostep_tstamp = true;
> -
> tx_swbd->do_twostep_tstamp = do_twostep_tstamp;
> tx_swbd->qbv_en = !!(priv->active_offloads & ENETC_F_QBV);
> tx_swbd->check_wb = tx_swbd->do_twostep_tstamp || tx_swbd->qbv_en;
> @@ -393,8 +418,6 @@ static int enetc_map_tx_buffs(struct enetc_bdr *tx_ring, struct sk_buff *skb)
> }
>
> if (do_onestep_tstamp) {
> - u32 tstamp = enetc_update_ptp_sync_msg(priv, skb);
> -
> /* Configure extension BD */
> temp_bd.ext.tstamp = cpu_to_le32(tstamp);
> e_flags |= ENETC_TXBD_E_FLAGS_ONE_STEP_PTP;
> @@ -3314,7 +3337,7 @@ int enetc_hwtstamp_set(struct net_device *ndev,
> struct enetc_ndev_priv *priv = netdev_priv(ndev);
> int err, new_offloads = priv->active_offloads;
>
> - if (!IS_ENABLED(CONFIG_FSL_ENETC_PTP_CLOCK))
> + if (!enetc_ptp_clock_is_enabled(priv->si))
> return -EOPNOTSUPP;
>
> switch (config->tx_type) {
> @@ -3364,7 +3387,7 @@ int enetc_hwtstamp_get(struct net_device *ndev,
> {
> struct enetc_ndev_priv *priv = netdev_priv(ndev);
>
> - if (!IS_ENABLED(CONFIG_FSL_ENETC_PTP_CLOCK))
> + if (!enetc_ptp_clock_is_enabled(priv->si))
> return -EOPNOTSUPP;
>
> if (priv->active_offloads & ENETC_F_TX_ONESTEP_SYNC_TSTAMP)
> diff --git a/drivers/net/ethernet/freescale/enetc/enetc.h b/drivers/net/ethernet/freescale/enetc/enetc.h
> index c65aa7b88122..815afdc2ec23 100644
> --- a/drivers/net/ethernet/freescale/enetc/enetc.h
> +++ b/drivers/net/ethernet/freescale/enetc/enetc.h
> @@ -598,6 +598,14 @@ static inline void enetc_cbd_free_data_mem(struct enetc_si *si, int size,
> void enetc_reset_ptcmsdur(struct enetc_hw *hw);
> void enetc_set_ptcmsdur(struct enetc_hw *hw, u32 *queue_max_sdu);
>
> +static inline bool enetc_ptp_clock_is_enabled(struct enetc_si *si)
> +{
> + if (is_enetc_rev1(si))
> + return IS_ENABLED(CONFIG_FSL_ENETC_PTP_CLOCK);
> +
> + return IS_ENABLED(CONFIG_PTP_NETC_V4_TIMER);
> +}
> +
> #ifdef CONFIG_FSL_ENETC_QOS
> int enetc_qos_query_caps(struct net_device *ndev, void *type_data);
> int enetc_setup_tc_taprio(struct net_device *ndev, void *type_data);
> diff --git a/drivers/net/ethernet/freescale/enetc/enetc4_hw.h b/drivers/net/ethernet/freescale/enetc/enetc4_hw.h
> index aa25b445d301..a8113c9057eb 100644
> --- a/drivers/net/ethernet/freescale/enetc/enetc4_hw.h
> +++ b/drivers/net/ethernet/freescale/enetc/enetc4_hw.h
> @@ -171,6 +171,12 @@
> /* Port MAC 0/1 Pause Quanta Threshold Register */
> #define ENETC4_PM_PAUSE_THRESH(mac) (0x5064 + (mac) * 0x400)
>
> +#define ENETC4_PM_SINGLE_STEP(mac) (0x50c0 + (mac) * 0x400)
> +#define PM_SINGLE_STEP_CH BIT(6)
> +#define PM_SINGLE_STEP_OFFSET GENMASK(15, 7)
> +#define PM_SINGLE_STEP_OFFSET_SET(o) FIELD_PREP(PM_SINGLE_STEP_OFFSET, o)
> +#define PM_SINGLE_STEP_EN BIT(31)
> +
> /* Port MAC 0 Interface Mode Control Register */
> #define ENETC4_PM_IF_MODE(mac) (0x5300 + (mac) * 0x400)
> #define PM_IF_MODE_IFMODE GENMASK(2, 0)
> diff --git a/drivers/net/ethernet/freescale/enetc/enetc4_pf.c b/drivers/net/ethernet/freescale/enetc/enetc4_pf.c
> index b3dc1afeefd1..107f59169e67 100644
> --- a/drivers/net/ethernet/freescale/enetc/enetc4_pf.c
> +++ b/drivers/net/ethernet/freescale/enetc/enetc4_pf.c
> @@ -569,6 +569,9 @@ static const struct net_device_ops enetc4_ndev_ops = {
> .ndo_set_features = enetc4_pf_set_features,
> .ndo_vlan_rx_add_vid = enetc_vlan_rx_add_vid,
> .ndo_vlan_rx_kill_vid = enetc_vlan_rx_del_vid,
> + .ndo_eth_ioctl = enetc_ioctl,
> + .ndo_hwtstamp_get = enetc_hwtstamp_get,
> + .ndo_hwtstamp_set = enetc_hwtstamp_set,
> };
>
> static struct phylink_pcs *
> diff --git a/drivers/net/ethernet/freescale/enetc/enetc_ethtool.c b/drivers/net/ethernet/freescale/enetc/enetc_ethtool.c
> index 961e76cd8489..b6014b1069de 100644
> --- a/drivers/net/ethernet/freescale/enetc/enetc_ethtool.c
> +++ b/drivers/net/ethernet/freescale/enetc/enetc_ethtool.c
> @@ -2,8 +2,11 @@
> /* Copyright 2017-2019 NXP */
>
> #include <linux/ethtool_netlink.h>
> +#include <linux/fsl/netc_global.h>
> #include <linux/net_tstamp.h>
> #include <linux/module.h>
> +#include <linux/of.h>
> +
> #include "enetc.h"
>
> static const u32 enetc_si_regs[] = {
> @@ -877,23 +880,49 @@ static int enetc_set_coalesce(struct net_device *ndev,
> return 0;
> }
>
> -static int enetc_get_ts_info(struct net_device *ndev,
> - struct kernel_ethtool_ts_info *info)
> +static struct pci_dev *enetc4_get_default_timer_pdev(struct enetc_si *si)
> {
> - struct enetc_ndev_priv *priv = netdev_priv(ndev);
> - int *phc_idx;
> -
> - phc_idx = symbol_get(enetc_phc_index);
> - if (phc_idx) {
> - info->phc_index = *phc_idx;
> - symbol_put(enetc_phc_index);
> + struct pci_bus *bus = si->pdev->bus;
> + int domain = pci_domain_nr(bus);
> + int bus_num = bus->number;
> + int devfn;
> +
> + switch (si->revision) {
> + case ENETC_REV_4_1:
> + devfn = PCI_DEVFN(24, 0);
> + break;
> + default:
> + return NULL;
> }
>
> - if (!IS_ENABLED(CONFIG_FSL_ENETC_PTP_CLOCK)) {
> - info->so_timestamping = SOF_TIMESTAMPING_TX_SOFTWARE;
> + return pci_dev_get(pci_get_domain_bus_and_slot(domain, bus_num, devfn));
> +}
>
> - return 0;
> - }
> +static struct pci_dev *enetc4_get_timer_pdev(struct enetc_si *si)
> +{
> + struct device_node *np = si->pdev->dev.of_node;
> + struct fwnode_handle *timer_fwnode;
> + struct device_node *timer_np;
> +
> + if (!np)
> + return enetc4_get_default_timer_pdev(si);
> +
> + timer_np = of_parse_phandle(np, "ptp-timer", 0);
> + if (!timer_np)
> + return enetc4_get_default_timer_pdev(si);
> +
> + timer_fwnode = of_fwnode_handle(timer_np);
> + of_node_put(timer_np);
> + if (!timer_fwnode)
> + return NULL;
> +
> + return pci_dev_get(to_pci_dev(timer_fwnode->dev));
> +}
> +
> +static void enetc_get_ts_generic_info(struct net_device *ndev,
> + struct kernel_ethtool_ts_info *info)
> +{
> + struct enetc_ndev_priv *priv = netdev_priv(ndev);
>
> info->so_timestamping = SOF_TIMESTAMPING_TX_HARDWARE |
> SOF_TIMESTAMPING_RX_HARDWARE |
> @@ -908,6 +937,42 @@ static int enetc_get_ts_info(struct net_device *ndev,
>
> info->rx_filters = (1 << HWTSTAMP_FILTER_NONE) |
> (1 << HWTSTAMP_FILTER_ALL);
> +}
> +
> +static int enetc_get_ts_info(struct net_device *ndev,
> + struct kernel_ethtool_ts_info *info)
> +{
> + struct enetc_ndev_priv *priv = netdev_priv(ndev);
> + struct enetc_si *si = priv->si;
> + struct pci_dev *timer_pdev;
> + int *phc_idx;
> +
> + if (!enetc_ptp_clock_is_enabled(si))
> + goto timestamp_tx_sw;
> +
> + if (is_enetc_rev1(si)) {
> + phc_idx = symbol_get(enetc_phc_index);
> + if (phc_idx) {
> + info->phc_index = *phc_idx;
> + symbol_put(enetc_phc_index);
> + }
> + } else {
> + timer_pdev = enetc4_get_timer_pdev(si);
> + if (!timer_pdev)
> + goto timestamp_tx_sw;
> +
> + info->phc_index = netc_timer_get_phc_index(timer_pdev);
> + pci_dev_put(timer_pdev);
> + if (info->phc_index < 0)
> + goto timestamp_tx_sw;
> + }
> +
> + enetc_get_ts_generic_info(ndev, info);
> +
> + return 0;
> +
> +timestamp_tx_sw:
> + info->so_timestamping = SOF_TIMESTAMPING_TX_SOFTWARE;
>
> return 0;
> }
> @@ -1296,6 +1361,7 @@ const struct ethtool_ops enetc4_pf_ethtool_ops = {
> .get_rxfh = enetc_get_rxfh,
> .set_rxfh = enetc_set_rxfh,
> .get_rxfh_fields = enetc_get_rxfh_fields,
> + .get_ts_info = enetc_get_ts_info,
> };
>
> void enetc_set_ethtool_ops(struct net_device *ndev)
> --
> 2.34.1
>