Re: [PATCH net-next v2] net: ti: icssg_prueth: add TAPRIO offload support

Roger Quadros
2023-09-21T19:29:50Z

Hi Danish,

On 21/09/2023 10:00, MD Danish Anwar wrote:

Can you please retain patch authorhsip?

> ICSSG dual-emac f/w supports Enhanced Scheduled Traffic (EST – defined
> in P802.1Qbv/D2.2 that later got included in IEEE 802.1Q-2018)
> configuration. EST allows express queue traffic to be scheduled
> (placed) on the wire at specific repeatable time intervals. In
> Linux kernel, EST configuration is done through tc command and
> the taprio scheduler in the net core implements a software only
> scheduler (SCH_TAPRIO). If the NIC is capable of EST configuration,
> user indicate "flag 2" in the command which is then parsed by
> taprio scheduler in net core and indicate that the command is to
> be offloaded to h/w. taprio then offloads the command to the
> driver by calling ndo_setup_tc() ndo ops. This patch implements
> ndo_setup_tc() to offload EST configuration to ICSSG.
>
> Signed-off-by: Roger Quadros <rogerq@ti.com>
> Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
> Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
> ---
> Cc: Roger Quadros <rogerq@ti.com>
> Cc: Andrew Lunn <andrew@lunn.ch>
>
> Changes from v1 to v2:
> *) Rebased on the latest next-20230821 linux-next.
> *) Dropped the RFC tag as merge window is open now.
> *) Splitted this patch from the switch mode series [v1].
> *) Removed TODO comment as asked by Andrew and Roger.
> *) Changed Copyright to 2023 as asked by Roger.
>
> v1: https://lore.kernel.org/all/20230830110847.1219515-1-danishanwar@ti.com/
>
> drivers/net/ethernet/ti/Makefile | 3 +-
> drivers/net/ethernet/ti/icssg/icssg_prueth.c | 5 +-
> drivers/net/ethernet/ti/icssg/icssg_prueth.h | 7 +
> drivers/net/ethernet/ti/icssg/icssg_qos.c | 286 +++++++++++++++++++
> drivers/net/ethernet/ti/icssg/icssg_qos.h | 119 ++++++++
> 5 files changed, 418 insertions(+), 2 deletions(-)
> create mode 100644 drivers/net/ethernet/ti/icssg/icssg_qos.c
> create mode 100644 drivers/net/ethernet/ti/icssg/icssg_qos.h
>
> diff --git a/drivers/net/ethernet/ti/Makefile b/drivers/net/ethernet/ti/Makefile
> index 34fd7a716ba6..0df60ded1b2d 100644
> --- a/drivers/net/ethernet/ti/Makefile
> +++ b/drivers/net/ethernet/ti/Makefile
> @@ -37,5 +37,6 @@ icssg-prueth-y := k3-cppi-desc-pool.o \
> icssg/icssg_config.o \
> icssg/icssg_mii_cfg.o \
> icssg/icssg_stats.o \
> - icssg/icssg_ethtool.o
> + icssg/icssg_ethtool.o \
> + icssg/icssg_qos.o
> obj-$(CONFIG_TI_ICSS_IEP) += icssg/icss_iep.o
> diff --git a/drivers/net/ethernet/ti/icssg/icssg_prueth.c b/drivers/net/ethernet/ti/icssg/icssg_prueth.c
> index 6635b28bc672..89c301716926 100644
> --- a/drivers/net/ethernet/ti/icssg/icssg_prueth.c
> +++ b/drivers/net/ethernet/ti/icssg/icssg_prueth.c
> @@ -1166,7 +1166,7 @@ static int emac_phy_connect(struct prueth_emac *emac)
> return 0;
> }
>
> -static u64 prueth_iep_gettime(void *clockops_data, struct ptp_system_timestamp *sts)
> +u64 prueth_iep_gettime(void *clockops_data, struct ptp_system_timestamp *sts)
> {
> u32 hi_rollover_count, hi_rollover_count_r;
> struct prueth_emac *emac = clockops_data;
> @@ -1403,6 +1403,8 @@ static int emac_ndo_open(struct net_device *ndev)
> napi_enable(&emac->tx_chns[i].napi_tx);
> napi_enable(&emac->napi_rx);
>
> + icssg_qos_tas_init(ndev);
> +
> /* start PHY */
> phy_start(ndev->phydev);
>
> @@ -1669,6 +1671,7 @@ static const struct net_device_ops emac_netdev_ops = {
> .ndo_set_rx_mode = emac_ndo_set_rx_mode,
> .ndo_eth_ioctl = emac_ndo_ioctl,
> .ndo_get_stats64 = emac_ndo_get_stats64,
> + .ndo_setup_tc = icssg_qos_ndo_setup_tc,
> };
>
> /* get emac_port corresponding to eth_node name */
> diff --git a/drivers/net/ethernet/ti/icssg/icssg_prueth.h b/drivers/net/ethernet/ti/icssg/icssg_prueth.h
> index 8b6d6b497010..5712a65bced4 100644
> --- a/drivers/net/ethernet/ti/icssg/icssg_prueth.h
> +++ b/drivers/net/ethernet/ti/icssg/icssg_prueth.h
> @@ -37,6 +37,7 @@
> #include "icssg_config.h"
> #include "icss_iep.h"
> #include "icssg_switch_map.h"
> +#include "icssg_qos.h"
>
> #define PRUETH_MAX_MTU (2000 - ETH_HLEN - ETH_FCS_LEN)
> #define PRUETH_MIN_PKT_SIZE (VLAN_ETH_ZLEN)
> @@ -174,6 +175,9 @@ struct prueth_emac {
>
> struct pruss_mem_region dram;
>
> + struct prueth_qos qos;
> + struct work_struct ts_work;
> +
> struct delayed_work stats_work;
> u64 stats[ICSSG_NUM_STATS];
> };
> @@ -285,4 +289,7 @@ u32 icssg_queue_level(struct prueth *prueth, int queue);
> void emac_stats_work_handler(struct work_struct *work);
> void emac_update_hardware_stats(struct prueth_emac *emac);
> int emac_get_stat_by_name(struct prueth_emac *emac, char *stat_name);
> +
> +u64 prueth_iep_gettime(void *clockops_data, struct ptp_system_timestamp *sts);
> +
> #endif /* __NET_TI_ICSSG_PRUETH_H */
> diff --git a/drivers/net/ethernet/ti/icssg/icssg_qos.c b/drivers/net/ethernet/ti/icssg/icssg_qos.c
> new file mode 100644
> index 000000000000..63a19142ee69
> --- /dev/null
> +++ b/drivers/net/ethernet/ti/icssg/icssg_qos.c
> @@ -0,0 +1,286 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Texas Instruments ICSSG PRUETH QoS submodule
> + * Copyright (C) 2023 Texas Instruments Incorporated - http://www.ti.com/
> + */
> +
> +#include <linux/printk.h>
> +#include "icssg_prueth.h"
> +#include "icssg_switch_map.h"
> +
> +static void tas_update_fw_list_pointers(struct prueth_emac *emac)
> +{
> + struct tas_config *tas = &emac->qos.tas.config;
> +
> + if ((readb(tas->active_list)) == TAS_LIST0) {
> + tas->fw_active_list = emac->dram.va + TAS_GATE_MASK_LIST0;
> + tas->fw_shadow_list = emac->dram.va + TAS_GATE_MASK_LIST1;
> + } else {
> + tas->fw_active_list = emac->dram.va + TAS_GATE_MASK_LIST1;
> + tas->fw_shadow_list = emac->dram.va + TAS_GATE_MASK_LIST0;
> + }
> +}
> +
> +static void tas_update_maxsdu_table(struct prueth_emac *emac)
> +{
> + struct tas_config *tas = &emac->qos.tas.config;
> + u16 __iomem *max_sdu_tbl_ptr;
> + u8 gate_idx;
> +
> + /* update the maxsdu table */
> + max_sdu_tbl_ptr = emac->dram.va + TAS_QUEUE_MAX_SDU_LIST;
> +
> + for (gate_idx = 0; gate_idx < TAS_MAX_NUM_QUEUES; gate_idx++)
> + writew(tas->max_sdu_table.max_sdu[gate_idx], &max_sdu_tbl_ptr[gate_idx]);
> +}
> +
> +static void tas_reset(struct prueth_emac *emac)
> +{
> + struct tas_config *tas = &emac->qos.tas.config;
> + int i;
> +
> + for (i = 0; i < TAS_MAX_NUM_QUEUES; i++)
> + tas->max_sdu_table.max_sdu[i] = 2048;
> +
> + tas_update_maxsdu_table(emac);
> +
> + writeb(TAS_LIST0, tas->active_list);
> +
> + memset_io(tas->fw_active_list, 0, sizeof(*tas->fw_active_list));
> + memset_io(tas->fw_shadow_list, 0, sizeof(*tas->fw_shadow_list));
> +}
> +
> +static int tas_set_state(struct prueth_emac *emac, enum tas_state state)
> +{
> + struct tas_config *tas = &emac->qos.tas.config;
> + int ret;
> +
> + if (tas->state == state)
> + return 0;
> +
> + switch (state) {
> + case TAS_STATE_RESET:
> + tas_reset(emac);
> + ret = emac_set_port_state(emac, ICSSG_EMAC_PORT_TAS_RESET);
> + tas->state = TAS_STATE_RESET;
> + break;
> + case TAS_STATE_ENABLE:
> + ret = emac_set_port_state(emac, ICSSG_EMAC_PORT_TAS_ENABLE);
> + tas->state = TAS_STATE_ENABLE;
> + break;
> + case TAS_STATE_DISABLE:
> + ret = emac_set_port_state(emac, ICSSG_EMAC_PORT_TAS_DISABLE);
> + tas->state = TAS_STATE_DISABLE;
> + break;
> + default:
> + netdev_err(emac->ndev, "%s: unsupported state\n", __func__);
> + ret = -EINVAL;
> + break;
> + }
> +
> + if (ret)
> + netdev_err(emac->ndev, "TAS set state failed %d\n", ret);
> + return ret;
> +}
> +
> +static int tas_set_trigger_list_change(struct prueth_emac *emac)
> +{
> + struct tc_taprio_qopt_offload *admin_list = emac->qos.tas.taprio_admin;
> + struct tas_config *tas = &emac->qos.tas.config;
> + struct ptp_system_timestamp sts;
> + u32 change_cycle_count;
> + u32 cycle_time;
> + u64 base_time;
> + u64 cur_time;
> +
> + cycle_time = admin_list->cycle_time - 4; /* -4ns to compensate for IEP wraparound time */
> + base_time = admin_list->base_time;
> + cur_time = prueth_iep_gettime(emac, &sts);
> +
> + if (base_time > cur_time)
> + change_cycle_count = DIV_ROUND_UP_ULL(base_time - cur_time, cycle_time);
> + else
> + change_cycle_count = 1;
> +
> + writel(cycle_time, emac->dram.va + TAS_ADMIN_CYCLE_TIME);
> + writel(change_cycle_count, emac->dram.va + TAS_CONFIG_CHANGE_CYCLE_COUNT);
> + writeb(admin_list->num_entries, emac->dram.va + TAS_ADMIN_LIST_LENGTH);
> +
> + /* config_change cleared by f/w to ack reception of new shadow list */
> + writeb(1, &tas->config_list->config_change);
> + /* config_pending cleared by f/w when new shadow list is copied to active list */
> + writeb(1, &tas->config_list->config_pending);
> +
> + return emac_set_port_state(emac, ICSSG_EMAC_PORT_TAS_TRIGGER);
> +}
> +
> +static int tas_update_oper_list(struct prueth_emac *emac)
> +{
> + struct tc_taprio_qopt_offload *admin_list = emac->qos.tas.taprio_admin;
> + struct tas_config *tas = &emac->qos.tas.config;
> + u32 tas_acc_gate_close_time = 0;
> + u8 idx, gate_idx, val;
> + int ret;
> +
> + tas_update_fw_list_pointers(emac);
> +
> + for (idx = 0; idx < admin_list->num_entries; idx++) {
> + writeb(admin_list->entries[idx].gate_mask,
> + &tas->fw_shadow_list->gate_mask_list[idx]);
> + tas_acc_gate_close_time += admin_list->entries[idx].interval;
> +
> + /* extend last entry till end of cycle time */
> + if (idx == admin_list->num_entries - 1)
> + writel(admin_list->cycle_time,
> + &tas->fw_shadow_list->win_end_time_list[idx]);
> + else
> + writel(tas_acc_gate_close_time,
> + &tas->fw_shadow_list->win_end_time_list[idx]);
> + }
> +
> + /* clear remaining entries */
> + for (idx = admin_list->num_entries; idx < TAS_MAX_CMD_LISTS; idx++) {
> + writeb(0, &tas->fw_shadow_list->gate_mask_list[idx]);
> + writel(0, &tas->fw_shadow_list->win_end_time_list[idx]);
> + }
> +
> + /* update the Array of gate close time for each queue in each window */
> + for (idx = 0 ; idx < admin_list->num_entries; idx++) {
> + /* On Linux, only PRUETH_MAX_TX_QUEUES are supported per port */
> + for (gate_idx = 0; gate_idx < PRUETH_MAX_TX_QUEUES; gate_idx++) {
> + u8 gate_mask_list_idx = readb(&tas->fw_shadow_list->gate_mask_list[idx]);
> + u32 gate_close_time = 0;
> +
> + if (gate_mask_list_idx & BIT(gate_idx))
> + gate_close_time = readl(&tas->fw_shadow_list->win_end_time_list[idx]);
> +
> + writel(gate_close_time,
> + &tas->fw_shadow_list->gate_close_time_list[idx][gate_idx]);
> + }
> + }
> +
> + /* tell f/w to swap active & shadow list */
> + ret = tas_set_trigger_list_change(emac);
> + if (ret) {
> + netdev_err(emac->ndev, "failed to swap f/w config list: %d\n", ret);
> + return ret;
> + }
> +
> + /* Wait for completion */
> + ret = readb_poll_timeout(&tas->config_list->config_change, val, !val,
> + USEC_PER_MSEC, 10 * USEC_PER_MSEC);
> + if (ret) {
> + netdev_err(emac->ndev, "TAS list change completion time out\n");
> + return ret;
> + }
> +
> + tas_update_fw_list_pointers(emac);
> +
> + return 0;
> +}
> +
> +static int emac_set_taprio(struct prueth_emac *emac)
> +{
> + struct tc_taprio_qopt_offload *taprio = emac->qos.tas.taprio_admin;
> + int ret;
> +
> + if (taprio->cmd == TAPRIO_CMD_DESTROY)
> + return tas_set_state(emac, TAS_STATE_DISABLE);
> +
> + if (taprio->cmd != TAPRIO_CMD_REPLACE)
> + return -EOPNOTSUPP;
> +
> + ret = tas_update_oper_list(emac);
> + if (ret)
> + return ret;
> +
> + return tas_set_state(emac, TAS_STATE_ENABLE);
> +}
> +
> +static void emac_cp_taprio(struct tc_taprio_qopt_offload *from,
> + struct tc_taprio_qopt_offload *to)
> +{
> + int i;
> +
> + *to = *from;
> + for (i = 0; i < from->num_entries; i++)
> + to->entries[i] = from->entries[i];
> +}
> +
> +static int emac_setup_taprio(struct net_device *ndev, struct tc_taprio_qopt_offload *taprio)

Please change this to
static int emac_setup_taprio(struct net_device *ndev, void *type_data)

and later add
struct tc_taprio_qopt_offload *taprio = type_data;
> +{
> + struct prueth_emac *emac = netdev_priv(ndev);
> + struct tc_taprio_qopt_offload *est_new;
> + int ret, idx;
> +
> + if (!netif_running(ndev)) {
> + netdev_err(ndev, "interface is down, link speed unknown\n");
> + return -ENETDOWN;
> + }

Do we really need this?

How about handling the taprio->cmd with a switch statement
and adding helper functions for each case?

So emac_setup_taprio() reduces to

static int emac_setup_taprio(struct net_device *ndev, void *type_data)
{
struct tc_taprio_qopt_offload *taprio = type_data;
int err = 0;

switch (taprio->cmd) {
case TAPRIO_CMD_REPLACE:
err = emac_taprio_replace(ndev, taprio);
break;
case TAPRIO_CMD_DESTROY:
emac_taprio_destroy(ndev);
break;
case TAPRIO_CMD_STATS:
emac_taprio_stats(ndev, &taprio->stats);
break;
case TAPRIO_CMD_QUEUE_STATS:
emac_taprio_queue_stats(ndev, &taprio->queue_stats);
break;
default:
err = -EOPNOTSUPP;
}

return err;
}

> +
> + if (taprio->cycle_time_extension) {
> + netdev_err(ndev, "Failed to set cycle time extension");
> + return -EOPNOTSUPP;
> + }
> +
> + if (taprio->num_entries == 0 ||
> + taprio->num_entries > TAS_MAX_CMD_LISTS) {
> + netdev_err(ndev, "unsupported num_entries %ld in taprio config\n",
> + taprio->num_entries);

please use NL_SET_ERR_MSG_FMT_MOD(taprio->mqprio->extack, ...)

> + return -EINVAL;
> + }
> +
> + /* If any time_interval is 0 in between the list, then exit */
> + for (idx = 0; idx < taprio->num_entries; idx++) {
> + if (taprio->entries[idx].interval == 0) {
> + netdev_err(ndev, "0 interval in taprio config not supported\n");

NL_SET_ERR_MSG_MOD()

> + return -EINVAL;
> + }
> + }
> +
> + if (emac->qos.tas.taprio_admin)
> + devm_kfree(&ndev->dev, emac->qos.tas.taprio_admin);
> +
> + est_new = devm_kzalloc(&ndev->dev,
> + struct_size(est_new, entries, taprio->num_entries),
> + GFP_KERNEL);
> + emac_cp_taprio(taprio, est_new);
> + emac->qos.tas.taprio_admin = est_new;
> + ret = emac_set_taprio(emac);
> + if (ret)
> + devm_kfree(&ndev->dev, est_new);

The checks and other code can be moved to relavant helper functions.

> +
> + return ret;
> +}
> +
> +int icssg_qos_ndo_setup_tc(struct net_device *ndev, enum tc_setup_type type,
> + void *type_data)
> +{
> + switch (type) {
> + case TC_SETUP_QDISC_TAPRIO:
> + return emac_setup_taprio(ndev, type_data);
> + default:
> + return -EOPNOTSUPP;
> + }
> +}
> +
> +void icssg_qos_tas_init(struct net_device *ndev)
> +{
> + struct prueth_emac *emac = netdev_priv(ndev);
> + bool need_setup = false;
> + struct tas_config *tas;
> +
> + tas = &emac->qos.tas.config;
> +
> + if (tas->state == TAS_STATE_ENABLE)
> + need_setup = true;
> +
> + tas->config_list = emac->dram.va + TAS_CONFIG_CHANGE_TIME;
> + tas->active_list = emac->dram.va + TAS_ACTIVE_LIST_INDEX;
> +
> + tas_update_fw_list_pointers(emac);
> +
> + tas_set_state(emac, TAS_STATE_RESET);
> +
> + if (need_setup)
> + emac_set_taprio(emac);
> +}

Do you have any cleanup to do on ndo_stop()?

> diff --git a/drivers/net/ethernet/ti/icssg/icssg_qos.h b/drivers/net/ethernet/ti/icssg/icssg_qos.h
> new file mode 100644
> index 000000000000..4e2ddf81d5ec
> --- /dev/null
> +++ b/drivers/net/ethernet/ti/icssg/icssg_qos.h
> @@ -0,0 +1,119 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright (C) 2023 Texas Instruments Incorporated - http://www.ti.com/
> + */
> +
> +#ifndef __NET_TI_ICSSG_QOS_H
> +#define __NET_TI_ICSSG_QOS_H
> +
> +#include <linux/atomic.h>
> +#include <linux/netdevice.h>
> +#include <net/pkt_sched.h>
> +
> +/**
> + * Maximum number of gate command entries in each list.
> + */
> +#define TAS_MAX_CMD_LISTS (16)
> +
> +/**
> + * Maximum number of transmit queues supported by implementation
> + */
> +#define TAS_MAX_NUM_QUEUES (8)
> +
> +/**
> + * Minimum cycle time supported by implementation (in ns)
> + */
> +#define TAS_MIN_CYCLE_TIME (1000000)
> +
> +/**
> + * Minimum TAS window duration supported by implementation (in ns)
> + */
> +#define TAS_MIN_WINDOW_DURATION (10000)
> +
> +/**
> + * List number 0 or 1. Also the value at memory location TAS_ACTIVE_LIST_INDEX
> + */
> +enum tas_list_num {
> + TAS_LIST0 = 0,
> + TAS_LIST1 = 1
> +};
> +
> +/**
> + * state of TAS in f/w
> + */
> +enum tas_state {
> + /* PRU's are idle */
> + TAS_STATE_DISABLE = 0,
> + /* Enable TAS */
> + TAS_STATE_ENABLE = 1,
> + /* Firmware will reset the state machine */
> + TAS_STATE_RESET = 2,
> +};
> +
> +/**
> + * Config state machine variables. See IEEE Std 802.1Q-2018 8.6.8.4
> + */
> +struct tas_config_list {
> + /* New list is copied at this time */
> + u64 config_change_time;
> + /* config change error counter, incremented if
> + * admin->BaseTime < current time and TAS_enabled is true
> + */
> + u32 config_change_error_counter;
> + /* True if list update is pending */
> + u8 config_pending;
> + /* Set to true when application trigger updating of admin list
> + * to active list, cleared when configChangeTime is updated
> + */
> + u8 config_change;
> +};
> +
> +/**
> + * Max SDU table. See IEEE Std 802.1Q-2018 12.29.1.1
> + */
> +struct tas_max_sdu_table {
> + u16 max_sdu[TAS_MAX_NUM_QUEUES];
> +};
> +
> +/**
> + * TAS List Structure based on firmware memory map
> + */
> +struct tas_firmware_list {
> + /* window gate mask list */
> + u8 gate_mask_list[TAS_MAX_CMD_LISTS];
> + /* window end time list */
> + u32 win_end_time_list[TAS_MAX_CMD_LISTS];
> + /* Array of gate close time for each queue in each window */
> + u32 gate_close_time_list[TAS_MAX_CMD_LISTS][TAS_MAX_NUM_QUEUES];
> +};
> +
> +/**
> + * Main Time Aware Shaper Handle
> + */
> +struct tas_config {
> + enum tas_state state;
> + struct tas_max_sdu_table max_sdu_table;
> + /* Config change variables */
> + struct tas_config_list __iomem *config_list;
> + /* Whether list 1 or list 2 is the operating list */
> + u8 __iomem *active_list;
> + /* active List pointer, used by firmware */
> + struct tas_firmware_list __iomem *fw_active_list;
> + /* shadow List pointer, used by driver */
> + struct tas_firmware_list __iomem *fw_shadow_list;
> +};
> +
> +struct prueth_qos_tas {
> + struct tc_taprio_qopt_offload *taprio_admin;
> + struct tc_taprio_qopt_offload *taprio_oper;
> + struct tas_config config;
> +};
> +
> +struct prueth_qos {
> + /* IET data structure goes here */
> + struct prueth_qos_tas tas;
> +};
> +
> +void icssg_qos_tas_init(struct net_device *ndev);
> +int icssg_qos_ndo_setup_tc(struct net_device *ndev, enum tc_setup_type type,
> + void *type_data);
> +#endif /* __NET_TI_ICSSG_QOS_H */
>
> base-commit: 940fcc189c51032dd0282cbee4497542c982ac59

--
cheers,
-roger