scsi: lpfc: Add EDC ELS support

When congestion management is enabled, issue EDC ELS to register congestion
signaling capabilities with the fabric. The response handling will process
the fabric parameters and set the reporting parameters.

Similarly, add support for receiving an EDC request from the fabric
generating a corresponding response.

Implement handlers for congestion signals from the fabric and maintain
statistics for them.

Link: https://lore.kernel.org/r/20210816162901.121235-6-jsmart2021@gmail.com
Co-developed-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 124 insertions, 3 deletions

diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index 5489cc7d06d5..3b6576d3be6d 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -6417,6 +6417,7 @@ lpfc_set_features(struct lpfc_hba *phba, LPFC_MBOXQ_t *mbox,
 		  uint32_t feature)
 {
 	uint32_t len;
+	u32 sig_freq = 0;
 
 	len = sizeof(struct lpfc_mbx_set_feature) -
 		sizeof(struct lpfc_sli4_cfg_mhdr);
@@ -6439,6 +6440,35 @@ lpfc_set_features(struct lpfc_hba *phba, LPFC_MBOXQ_t *mbox,
 		mbox->u.mqe.un.set_feature.feature = LPFC_SET_MDS_DIAGS;
 		mbox->u.mqe.un.set_feature.param_len = 8;
 		break;
+	case LPFC_SET_CGN_SIGNAL:
+		if (phba->cmf_active_mode == LPFC_CFG_OFF)
+			sig_freq = 0;
+		else
+			sig_freq = phba->cgn_sig_freq;
+
+		if (phba->cgn_reg_signal == EDC_CG_SIG_WARN_ALARM) {
+			bf_set(lpfc_mbx_set_feature_CGN_alarm_freq,
+			       &mbox->u.mqe.un.set_feature, sig_freq);
+			bf_set(lpfc_mbx_set_feature_CGN_warn_freq,
+			       &mbox->u.mqe.un.set_feature, sig_freq);
+		}
+
+		if (phba->cgn_reg_signal == EDC_CG_SIG_WARN_ONLY)
+			bf_set(lpfc_mbx_set_feature_CGN_warn_freq,
+			       &mbox->u.mqe.un.set_feature, sig_freq);
+
+		if (phba->cmf_active_mode == LPFC_CFG_OFF ||
+		    phba->cgn_reg_signal == EDC_CG_SIG_NOTSUPPORTED)
+			sig_freq = 0;
+		else
+			sig_freq = lpfc_acqe_cgn_frequency;
+
+		bf_set(lpfc_mbx_set_feature_CGN_acqe_freq,
+		       &mbox->u.mqe.un.set_feature, sig_freq);
+
+		mbox->u.mqe.un.set_feature.feature = LPFC_SET_CGN_SIGNAL;
+		mbox->u.mqe.un.set_feature.param_len = 12;
+		break;
 	case LPFC_SET_DUAL_DUMP:
 		bf_set(lpfc_mbx_set_feature_dd,
 		       &mbox->u.mqe.un.set_feature, LPFC_ENABLE_DUAL_DUMP);
@@ -7445,6 +7475,91 @@ lpfc_post_rq_buffer(struct lpfc_hba *phba, struct lpfc_queue *hrq,
 	return 1;
 }
 
+static void
+lpfc_mbx_cmpl_cgn_set_ftrs(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
+{
+	struct lpfc_vport *vport = pmb->vport;
+	union lpfc_sli4_cfg_shdr *shdr;
+	u32 shdr_status, shdr_add_status;
+	u32 sig, acqe;
+
+	/* Two outcomes. (1) Set featurs was successul and EDC negotiation
+	 * is done. (2) Mailbox failed and send FPIN support only.
+	 */
+	shdr = (union lpfc_sli4_cfg_shdr *)
+		&pmb->u.mqe.un.sli4_config.header.cfg_shdr;
+	shdr_status = bf_get(lpfc_mbox_hdr_status, &shdr->response);
+	shdr_add_status = bf_get(lpfc_mbox_hdr_add_status, &shdr->response);
+	if (shdr_status || shdr_add_status || pmb->u.mb.mbxStatus) {
+		lpfc_printf_log(phba, KERN_ERR, LOG_INIT | LOG_CGN_MGMT,
+				"2516 CGN SET_FEATURE mbox failed with "
+				"status x%x add_status x%x, mbx status x%x "
+				"Reset Congestion to FPINs only\n",
+				shdr_status, shdr_add_status,
+				pmb->u.mb.mbxStatus);
+		/* If there is a mbox error, move on to RDF */
+		phba->cgn_reg_signal = EDC_CG_SIG_NOTSUPPORTED;
+		phba->cgn_reg_fpin = LPFC_CGN_FPIN_WARN | LPFC_CGN_FPIN_ALARM;
+		goto out;
+	}
+
+	/* Zero out Congestion Signal ACQE counter */
+	phba->cgn_acqe_cnt = 0;
+	atomic64_set(&phba->cgn_acqe_stat.warn, 0);
+	atomic64_set(&phba->cgn_acqe_stat.alarm, 0);
+
+	acqe = bf_get(lpfc_mbx_set_feature_CGN_acqe_freq,
+		      &pmb->u.mqe.un.set_feature);
+	sig = bf_get(lpfc_mbx_set_feature_CGN_warn_freq,
+		     &pmb->u.mqe.un.set_feature);
+	lpfc_printf_log(phba, KERN_INFO, LOG_CGN_MGMT,
+			"4620 SET_FEATURES Success: Freq: %ds %dms "
+			" Reg: x%x x%x\n", acqe, sig,
+			phba->cgn_reg_signal, phba->cgn_reg_fpin);
+out:
+	mempool_free(pmb, phba->mbox_mem_pool);
+
+	/* Register for FPIN events from the fabric now that the
+	 * EDC common_set_features has completed.
+	 */
+	lpfc_issue_els_rdf(vport, 0);
+}
+
+int
+lpfc_config_cgn_signal(struct lpfc_hba *phba)
+{
+	LPFC_MBOXQ_t *mboxq;
+	u32 rc;
+
+	mboxq = (LPFC_MBOXQ_t *)mempool_alloc(phba->mbox_mem_pool, GFP_KERNEL);
+	if (!mboxq)
+		goto out_rdf;
+
+	lpfc_set_features(phba, mboxq, LPFC_SET_CGN_SIGNAL);
+	mboxq->vport = phba->pport;
+	mboxq->mbox_cmpl = lpfc_mbx_cmpl_cgn_set_ftrs;
+
+	lpfc_printf_log(phba, KERN_INFO, LOG_CGN_MGMT,
+			"4621 SET_FEATURES: FREQ sig x%x acqe x%x: "
+			"Reg: x%x x%x\n",
+			phba->cgn_sig_freq, lpfc_acqe_cgn_frequency,
+			phba->cgn_reg_signal, phba->cgn_reg_fpin);
+
+	rc = lpfc_sli_issue_mbox(phba, mboxq, MBX_NOWAIT);
+	if (rc == MBX_NOT_FINISHED)
+		goto out;
+	return 0;
+
+out:
+	mempool_free(mboxq, phba->mbox_mem_pool);
+out_rdf:
+	/* If there is a mbox error, move on to RDF */
+	phba->cgn_reg_fpin = LPFC_CGN_FPIN_WARN | LPFC_CGN_FPIN_ALARM;
+	phba->cgn_reg_signal = EDC_CG_SIG_NOTSUPPORTED;
+	lpfc_issue_els_rdf(phba->pport, 0);
+	return -EIO;
+}
+
 /**
  * lpfc_init_idle_stat_hb - Initialize idle_stat tracking
  * @phba: pointer to lpfc hba data structure.
@@ -7476,7 +7591,8 @@ static void lpfc_init_idle_stat_hb(struct lpfc_hba *phba)
 		idle_stat->prev_idle = get_cpu_idle_time(i, &wall, 1);
 		idle_stat->prev_wall = wall;
 
-		if (phba->nvmet_support)
+		if (phba->nvmet_support ||
+		    phba->cmf_active_mode != LPFC_CFG_OFF)
 			cq->poll_mode = LPFC_QUEUE_WORK;
 		else
 			cq->poll_mode = LPFC_IRQ_POLL;
@@ -9947,6 +10063,7 @@ lpfc_sli4_iocb2wqe(struct lpfc_hba *phba, struct lpfc_iocbq *iocbq,
 			if (pcmd && (*pcmd == ELS_CMD_FLOGI ||
 				*pcmd == ELS_CMD_SCR ||
 				*pcmd == ELS_CMD_RDF ||
+				*pcmd == ELS_CMD_EDC ||
 				*pcmd == ELS_CMD_RSCN_XMT ||
 				*pcmd == ELS_CMD_FDISC ||
 				*pcmd == ELS_CMD_LOGO ||
@@ -14814,8 +14931,12 @@ static void lpfc_sli4_sched_cq_work(struct lpfc_hba *phba,
 
 	switch (cq->poll_mode) {
 	case LPFC_IRQ_POLL:
-		irq_poll_sched(&cq->iop);
-		break;
+		/* CGN mgmt is mutually exclusive from softirq processing */
+		if (phba->cmf_active_mode == LPFC_CFG_OFF) {
+			irq_poll_sched(&cq->iop);
+			break;
+		}
+		fallthrough;
 	case LPFC_QUEUE_WORK:
 	default:
 		if (is_kdump_kernel())