Re: [PATCH net 1/2] net: ti: icssg-prueth: Fix firmware load sequence.

[Anwar, Md Danish]

On 11/11/2024 6:33 PM, Roger Quadros wrote:
> Hi,
> 
> On 06/11/2024 09:40, Meghana Malladi wrote:
>> From: MD Danish Anwar <danishanwar@xxxxxx>
>>
>> Timesync related operations are ran in PRU0 cores for both ICSSG SLICE0
>> and SLICE1. Currently whenever any ICSSG interface comes up we load the
>> respective firmwares to PRU cores and whenever interface goes down, we
>> stop the respective cores. Due to this, when SLICE0 goes down while
>> SLICE1 is still active, PRU0 firmwares are unloaded and PRU0 core is
>> stopped. This results in clock jump for SLICE1 interface as the timesync
>> related operations are no longer running.
>>
>> Fix this by running both PRU0 and PRU1 firmwares as long as at least 1
>> ICSSG interface is up.
>>
>> rx_flow_id is updated before firmware is loaded. Once firmware is loaded,
>> it reads the flow_id and uses it for rx. emac_fdb_flow_id_updated() is
>> used to let firmware know that the flow_id has been updated and to use the
>> latest rx_flow_id.
> 
> is rx_flow_id releated to timesync releated issue that this patch is fixing?
> If not please split it into separate patch and mention what functionality
> it is fixing.
> 

Roger, rx_flow_id is not related to timesync. However loading both
SLICE0 and SLICE1 firmware together results in wrong rx_flow_id used by
firmware for the interface that is brought later.

When eth0 (SLICE0) is brought up, it's flow_id is obtained from dma and
written to SMEM. Slice0 and Slice1 both firmwares are loaded. Firmware
reads the flow_id from SMEM and uses it for RX.

Second interface eth1 (SLICE1) comes up, it's flow id is obtained from
dma and written to SMEM. However firmware doesn't read the flow ID
again. It only reads it once when loaded and uses that through out. The
flow id for this interface remains 0 and that results in RX being broken.

To fix this, emac_fdb_flow_id_updated() is added which will let firmware
know that we have updated the flow_id and use the latest one.

This not related to timesync instead related to the fix of timesync
issue. Breaking this into separate patch will result in RX (ICSSG) being
broken at the former patch.

In order to avoid feature breakage at the former patch, the change
related to flow_id update is kept in the same patch.

If you think having the feature broken is OK, the patch can be splitted.
However IMO, these chanegs should be together in one patch.

>>
>> Fixes: c1e0230eeaab ("net: ti: icss-iep: Add IEP driver")
>> Signed-off-by: MD Danish Anwar <danishanwar@xxxxxx>
>> Signed-off-by: Meghana Malladi <m-malladi@xxxxxx>
>> ---
>>  drivers/net/ethernet/ti/icssg/icssg_config.c | 28 ++++++++++
>>  drivers/net/ethernet/ti/icssg/icssg_config.h |  1 +
>>  drivers/net/ethernet/ti/icssg/icssg_prueth.c | 58 ++++++++++++++++----
>>  drivers/net/ethernet/ti/icssg/icssg_prueth.h |  1 +
>>  4 files changed, 77 insertions(+), 11 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/ti/icssg/icssg_config.c b/drivers/net/ethernet/ti/icssg/icssg_config.c
>> index 5d2491c2943a..f1f0c8659e2d 100644
>> --- a/drivers/net/ethernet/ti/icssg/icssg_config.c
>> +++ b/drivers/net/ethernet/ti/icssg/icssg_config.c
>> @@ -786,3 +786,31 @@ void icssg_set_pvid(struct prueth *prueth, u8 vid, u8 port)
>>  		writel(pvid, prueth->shram.va + EMAC_ICSSG_SWITCH_PORT0_DEFAULT_VLAN_OFFSET);
>>  }
>>  EXPORT_SYMBOL_GPL(icssg_set_pvid);
>> +
>> +int emac_fdb_flow_id_updated(struct prueth_emac *emac)
>> +{
>> +	struct mgmt_cmd_rsp fdb_cmd_rsp = { 0 };
>> +	int slice = prueth_emac_slice(emac);
>> +	struct mgmt_cmd fdb_cmd = { 0 };
>> +	int ret = 0;
>> +
>> +	fdb_cmd.header = ICSSG_FW_MGMT_CMD_HEADER;
>> +	fdb_cmd.type   = ICSSG_FW_MGMT_FDB_CMD_TYPE_RX_FLOW;
>> +	fdb_cmd.seqnum = ++(emac->prueth->icssg_hwcmdseq);
>> +	fdb_cmd.param  = 0;
>> +
>> +	fdb_cmd.param |= (slice << 4);
>> +	fdb_cmd.cmd_args[0] = 0;
>> +
>> +	ret = icssg_send_fdb_msg(emac, &fdb_cmd, &fdb_cmd_rsp);
>> +
>> +	if (ret)
>> +		return ret;
>> +
>> +	WARN_ON(fdb_cmd.seqnum != fdb_cmd_rsp.seqnum);
>> +	if (fdb_cmd_rsp.status == 1)
>> +		return 0;
>> +
>> +	return -EINVAL;
>> +}
>> +EXPORT_SYMBOL_GPL(emac_fdb_flow_id_updated);
>> diff --git a/drivers/net/ethernet/ti/icssg/icssg_config.h b/drivers/net/ethernet/ti/icssg/icssg_config.h
>> index 92c2deaa3068..c884e9fa099e 100644
>> --- a/drivers/net/ethernet/ti/icssg/icssg_config.h
>> +++ b/drivers/net/ethernet/ti/icssg/icssg_config.h
>> @@ -55,6 +55,7 @@ struct icssg_rxq_ctx {
>>  #define ICSSG_FW_MGMT_FDB_CMD_TYPE	0x03
>>  #define ICSSG_FW_MGMT_CMD_TYPE		0x04
>>  #define ICSSG_FW_MGMT_PKT		0x80000000
>> +#define ICSSG_FW_MGMT_FDB_CMD_TYPE_RX_FLOW	0x05
>>  
>>  struct icssg_r30_cmd {
>>  	u32 cmd[4];
>> diff --git a/drivers/net/ethernet/ti/icssg/icssg_prueth.c b/drivers/net/ethernet/ti/icssg/icssg_prueth.c
>> index 0556910938fa..9df67539285b 100644
>> --- a/drivers/net/ethernet/ti/icssg/icssg_prueth.c
>> +++ b/drivers/net/ethernet/ti/icssg/icssg_prueth.c
>> @@ -534,6 +534,7 @@ static int emac_ndo_open(struct net_device *ndev)
>>  {
>>  	struct prueth_emac *emac = netdev_priv(ndev);
>>  	int ret, i, num_data_chn = emac->tx_ch_num;
>> +	struct icssg_flow_cfg __iomem *flow_cfg;
>>  	struct prueth *prueth = emac->prueth;
>>  	int slice = prueth_emac_slice(emac);
>>  	struct device *dev = prueth->dev;
>> @@ -549,8 +550,12 @@ static int emac_ndo_open(struct net_device *ndev)
>>  	/* set h/w MAC as user might have re-configured */
>>  	ether_addr_copy(emac->mac_addr, ndev->dev_addr);
>>  
>> +	if (!prueth->emacs_initialized) {
>> +		icssg_class_default(prueth->miig_rt, ICSS_SLICE0, 0, false);
>> +		icssg_class_default(prueth->miig_rt, ICSS_SLICE1, 0, false);
>> +	}
>> +
>>  	icssg_class_set_mac_addr(prueth->miig_rt, slice, emac->mac_addr);
>> -	icssg_class_default(prueth->miig_rt, slice, 0, false);
>>  	icssg_ft1_set_mac_addr(prueth->miig_rt, slice, emac->mac_addr);
>>  
>>  	/* Notify the stack of the actual queue counts. */
>> @@ -588,10 +593,31 @@ static int emac_ndo_open(struct net_device *ndev)
>>  		goto cleanup_napi;
>>  	}
>>  
>> -	/* reset and start PRU firmware */
>> -	ret = prueth_emac_start(prueth, emac);
>> -	if (ret)
>> -		goto free_rx_irq;
>> +	if (!prueth->emacs_initialized) {
>> +		if (prueth->emac[ICSS_SLICE0]) {
>> +			ret = prueth_emac_start(prueth, prueth->emac[ICSS_SLICE0]);
>> +			if (ret) {
>> +				netdev_err(ndev, "unable to start fw for slice %d", ICSS_SLICE0);
>> +				goto free_rx_irq;
>> +			}
>> +		}
>> +		if (prueth->emac[ICSS_SLICE1]) {
>> +			ret = prueth_emac_start(prueth, prueth->emac[ICSS_SLICE1]);
>> +			if (ret) {
>> +				netdev_err(ndev, "unable to start fw for slice %d", ICSS_SLICE1);
>> +				goto halt_slice0_prus;
>> +			}
> 
> Did I understand right: SLICE0 needs to be always running if any of the
> interface is up but SLICE0 doesn't need to be running if only SLICE0

I think you meant `but SLICE1 doesn't need to be running if only SLICE0`

> interface is running.
> 
> If yes then you need to update the patch so SLICE1 is not always running.
> 

For Timesync - YES. Only slice0 is needed to be always running. However
these both firmwares have some more inter dependencies, timesync is just
one of them. As a result, firmware team has recommended to keep both
Slice0 and Slice1 firmware running as long as at least one ICSSG
interface is up. Stop both firmware only if no ICSSG interface is up.

I think the commit message can be modified to state that the dependecy
is not only SLICE0 but on SLICE1 as well and they both need to be running.

>> +		}
>> +	}
>> +
>> +	flow_cfg = emac->dram.va + ICSSG_CONFIG_OFFSET + PSI_L_REGULAR_FLOW_ID_BASE_OFFSET;
>> +	writew(emac->rx_flow_id_base, &flow_cfg->rx_base_flow);
>> +	ret = emac_fdb_flow_id_updated(emac);
>> +
>> +	if (ret) {
>> +		netdev_err(ndev, "Failed to update Rx Flow ID %d", ret);
>> +		goto stop;
>> +	}
>>  
>>  	icssg_mii_update_mtu(prueth->mii_rt, slice, ndev->max_mtu);
>>  
>> @@ -644,7 +670,11 @@ static int emac_ndo_open(struct net_device *ndev)
>>  free_tx_ts_irq:
>>  	free_irq(emac->tx_ts_irq, emac);
>>  stop:
>> -	prueth_emac_stop(emac);
>> +	if (prueth->emac[ICSS_SLICE1])
>> +		prueth_emac_stop(prueth->emac[ICSS_SLICE1]);
>> +halt_slice0_prus:
>> +	if (prueth->emac[ICSS_SLICE0])
>> +		prueth_emac_stop(prueth->emac[ICSS_SLICE0]);
>>  free_rx_irq:
>>  	free_irq(emac->rx_chns.irq[rx_flow], emac);
>>  cleanup_napi:
>> @@ -680,7 +710,10 @@ static int emac_ndo_stop(struct net_device *ndev)
>>  	if (ndev->phydev)
>>  		phy_stop(ndev->phydev);
>>  
>> -	icssg_class_disable(prueth->miig_rt, prueth_emac_slice(emac));
>> +	if (prueth->emacs_initialized == 1) {
>> +		icssg_class_disable(prueth->miig_rt, ICSS_SLICE0);
>> +		icssg_class_disable(prueth->miig_rt, ICSS_SLICE1);
>> +	}
>>  
>>  	if (emac->prueth->is_hsr_offload_mode)
>>  		__dev_mc_unsync(ndev, icssg_prueth_hsr_del_mcast);
>> @@ -719,11 +752,14 @@ static int emac_ndo_stop(struct net_device *ndev)
>>  	/* Destroying the queued work in ndo_stop() */
>>  	cancel_delayed_work_sync(&emac->stats_work);
>>  
>> -	if (prueth->emacs_initialized == 1)
>> +	if (prueth->emacs_initialized == 1) {
>>  		icss_iep_exit(emac->iep);
>> -
>> -	/* stop PRUs */
>> -	prueth_emac_stop(emac);
>> +		/* stop PRUs */
>> +		if (prueth->emac[ICSS_SLICE0])
>> +			prueth_emac_stop(prueth->emac[ICSS_SLICE0]);
>> +		if (prueth->emac[ICSS_SLICE1])
>> +			prueth_emac_stop(prueth->emac[ICSS_SLICE1]);
>> +	}
>>  
>>  	free_irq(emac->tx_ts_irq, emac);
>>  
>> diff --git a/drivers/net/ethernet/ti/icssg/icssg_prueth.h b/drivers/net/ethernet/ti/icssg/icssg_prueth.h
>> index 8722bb4a268a..c4f5f0349ae7 100644
>> --- a/drivers/net/ethernet/ti/icssg/icssg_prueth.h
>> +++ b/drivers/net/ethernet/ti/icssg/icssg_prueth.h
>> @@ -365,6 +365,7 @@ void icssg_vtbl_modify(struct prueth_emac *emac, u8 vid, u8 port_mask,
>>  		       u8 untag_mask, bool add);
>>  u16 icssg_get_pvid(struct prueth_emac *emac);
>>  void icssg_set_pvid(struct prueth *prueth, u8 vid, u8 port);
>> +int emac_fdb_flow_id_updated(struct prueth_emac *emac);
>>  #define prueth_napi_to_tx_chn(pnapi) \
>>  	container_of(pnapi, struct prueth_tx_chn, napi_tx)
>>  
> 

-- 
Thanks and Regards,
Md Danish Anwar