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

From: Anwar, Md Danish
Date: Fri Sep 22 2023 - 07:30:34 EST


On 9/22/2023 4:10 PM, Roger Quadros wrote:
>
>
> 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@xxxxxx>
>>>> Signed-off-by: Vignesh Raghavendra <vigneshr@xxxxxx>
>>>> Signed-off-by: MD Danish Anwar <danishanwar@xxxxxx>
>>>> ---
>>>> Cc: Roger Quadros <rogerq@xxxxxx>
>>>> Cc: Andrew Lunn <andrew@xxxxxxx>
>>>>
>>>> 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@xxxxxx/
>>>>
>>>> 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.
>

Sure. I'll do that.

>>
>>> 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;
>>> }
>>>
>

--
Thanks and Regards,
Md Danish Anwar