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

Roger Quadros
2023-09-22T10:40:39Z

On 22/09/2023 07:58, MD Danish Anwar wrote:
> On 21/09/23 16:12, Roger Quadros wrote:
>> Hi Danish,
>>
>> On 21/09/2023 10:00, MD Danish Anwar wrote:
>>
>> Can you please retain patch authorhsip?
>>
>
> Sure Roger. This patch was not applying clearly on latest linux-next so
> I had to manually apply it. I must have lost authorship while doing
> this. I will reset the authorship.
>
>>> 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;
>
> Sure.
>
>>> +{
>>> + 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?
>>
>
> emac_set_taprio() is already doing something like this.
> It only implements TAPRIO_CMD_REPLACE and TAPRIO_CMD_DESTROY. Others are
> not supported.
>
> 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);
> }
>
> emac_setup_taprio() is first doing all the neccessary check and then
> calling emac_set_taprio(), which actually perform actions based on the
> taprio->cmd. I think I'll keep this as it is.

OK but pleae at least use switch statement in emac_set_taprio()
and error out in default: 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;
>> }
>>

--
cheers,
-roger