[SCSI] lpfc 8.3.32: Fix ability to change FCP EQ delay multiplier

Fix fcp_imax module parameter to dynamically change FCP EQ delay multiplier

Signed-off-by: Alex Iannicelli <alex.iannicelli@emulex.com>
Signed-off-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

4 files changed, 185 insertions, 8 deletions

diff --git a/drivers/scsi/lpfc/lpfc_attr.c b/drivers/scsi/lpfc/lpfc_attr.c
index 5eb2bc116183..adef5bb2100e 100644
--- a/drivers/scsi/lpfc/lpfc_attr.c
+++ b/drivers/scsi/lpfc/lpfc_attr.c
@@ -3617,6 +3617,91 @@ lpfc_sriov_nr_virtfn_init(struct lpfc_hba *phba, int val)
 static DEVICE_ATTR(lpfc_sriov_nr_virtfn, S_IRUGO | S_IWUSR,
 		   lpfc_sriov_nr_virtfn_show, lpfc_sriov_nr_virtfn_store);
 
+/**
+ * lpfc_fcp_imax_store
+ *
+ * @dev: class device that is converted into a Scsi_host.
+ * @attr: device attribute, not used.
+ * @buf: string with the number of fast-path FCP interrupts per second.
+ * @count: unused variable.
+ *
+ * Description:
+ * If val is in a valid range [636,651042], then set the adapter's
+ * maximum number of fast-path FCP interrupts per second.
+ *
+ * Returns:
+ * length of the buf on success if val is in range the intended mode
+ * is supported.
+ * -EINVAL if val out of range or intended mode is not supported.
+ **/
+static ssize_t
+lpfc_fcp_imax_store(struct device *dev, struct device_attribute *attr,
+			 const char *buf, size_t count)
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct lpfc_vport *vport = (struct lpfc_vport *)shost->hostdata;
+	struct lpfc_hba *phba = vport->phba;
+	int val = 0, i;
+
+	/* Sanity check on user data */
+	if (!isdigit(buf[0]))
+		return -EINVAL;
+	if (sscanf(buf, "%i", &val) != 1)
+		return -EINVAL;
+
+	/* Value range is [636,651042] */
+	if (val < LPFC_MIM_IMAX || val > LPFC_DMULT_CONST)
+		return -EINVAL;
+
+	phba->cfg_fcp_imax = (uint32_t)val;
+	for (i = 0; i < phba->cfg_fcp_eq_count; i += LPFC_MAX_EQ_DELAY)
+		lpfc_modify_fcp_eq_delay(phba, i);
+
+	return strlen(buf);
+}
+
+/*
+# lpfc_fcp_imax: The maximum number of fast-path FCP interrupts per second
+#
+# Value range is [636,651042]. Default value is 10000.
+*/
+static int lpfc_fcp_imax = LPFC_FP_DEF_IMAX;
+module_param(lpfc_fcp_imax, int, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(lpfc_fcp_imax,
+	    "Set the maximum number of fast-path FCP interrupts per second");
+lpfc_param_show(fcp_imax)
+
+/**
+ * lpfc_fcp_imax_init - Set the initial sr-iov virtual function enable
+ * @phba: lpfc_hba pointer.
+ * @val: link speed value.
+ *
+ * Description:
+ * If val is in a valid range [636,651042], then initialize the adapter's
+ * maximum number of fast-path FCP interrupts per second.
+ *
+ * Returns:
+ * zero if val saved.
+ * -EINVAL val out of range
+ **/
+static int
+lpfc_fcp_imax_init(struct lpfc_hba *phba, int val)
+{
+	if (val >= LPFC_MIM_IMAX && val <= LPFC_DMULT_CONST) {
+		phba->cfg_fcp_imax = val;
+		return 0;
+	}
+
+	lpfc_printf_log(phba, KERN_ERR, LOG_INIT,
+			"3016 fcp_imax: %d out of range, using default\n", val);
+	phba->cfg_fcp_imax = LPFC_FP_DEF_IMAX;
+
+	return 0;
+}
+
+static DEVICE_ATTR(lpfc_fcp_imax, S_IRUGO | S_IWUSR,
+		   lpfc_fcp_imax_show, lpfc_fcp_imax_store);
+
 /*
 # lpfc_fcp_class:  Determines FC class to use for the FCP protocol.
 # Value range is [2,3]. Default value is 3.
@@ -3758,14 +3843,6 @@ LPFC_ATTR_R(use_msi, 2, 0, 2, "Use Message Signaled Interrupts (1) or "
 	    "MSI-X (2), if possible");
 
 /*
-# lpfc_fcp_imax: Set the maximum number of fast-path FCP interrupts per second
-#
-# Value range is [636,651042]. Default value is 10000.
-*/
-LPFC_ATTR_R(fcp_imax, LPFC_FP_DEF_IMAX, LPFC_MIM_IMAX, LPFC_DMULT_CONST,
-	    "Set the maximum number of fast-path FCP interrupts per second");
-
-/*
 # lpfc_fcp_wq_count: Set the number of fast-path FCP work queues
 #
 # Value range is [1,31]. Default value is 4.
diff --git a/drivers/scsi/lpfc/lpfc_hw4.h b/drivers/scsi/lpfc/lpfc_hw4.h
index f1946dfda5b4..a631ebf4158d 100644
--- a/drivers/scsi/lpfc/lpfc_hw4.h
+++ b/drivers/scsi/lpfc/lpfc_hw4.h
@@ -874,6 +874,7 @@ struct mbox_header {
 #define LPFC_MBOX_OPCODE_MQ_CREATE			0x15
 #define LPFC_MBOX_OPCODE_GET_CNTL_ATTRIBUTES		0x20
 #define LPFC_MBOX_OPCODE_NOP				0x21
+#define LPFC_MBOX_OPCODE_MODIFY_EQ_DELAY		0x29
 #define LPFC_MBOX_OPCODE_MQ_DESTROY			0x35
 #define LPFC_MBOX_OPCODE_CQ_DESTROY			0x36
 #define LPFC_MBOX_OPCODE_EQ_DESTROY			0x37
@@ -940,6 +941,13 @@ struct eq_context {
 	uint32_t reserved3;
 };
 
+struct eq_delay_info {
+	uint32_t eq_id;
+	uint32_t phase;
+	uint32_t delay_multi;
+};
+#define	LPFC_MAX_EQ_DELAY	8
+
 struct sgl_page_pairs {
 	uint32_t sgl_pg0_addr_lo;
 	uint32_t sgl_pg0_addr_hi;
@@ -1002,6 +1010,19 @@ struct lpfc_mbx_eq_create {
 	} u;
 };
 
+struct lpfc_mbx_modify_eq_delay {
+	struct mbox_header header;
+	union {
+		struct {
+			uint32_t num_eq;
+			struct eq_delay_info eq[LPFC_MAX_EQ_DELAY];
+		} request;
+		struct {
+			uint32_t word0;
+		} response;
+	} u;
+};
+
 struct lpfc_mbx_eq_destroy {
 	struct mbox_header header;
 	union {
@@ -2875,6 +2896,7 @@ struct lpfc_mqe {
 		struct lpfc_mbx_mq_create mq_create;
 		struct lpfc_mbx_mq_create_ext mq_create_ext;
 		struct lpfc_mbx_eq_create eq_create;
+		struct lpfc_mbx_modify_eq_delay eq_delay;
 		struct lpfc_mbx_cq_create cq_create;
 		struct lpfc_mbx_wq_create wq_create;
 		struct lpfc_mbx_rq_create rq_create;
diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index 3333e64703a3..9cbd20b1328b 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -12048,6 +12048,83 @@ out_fail:
 }
 
 /**
+ * lpfc_modify_fcp_eq_delay - Modify Delay Multiplier on FCP EQs
+ * @phba: HBA structure that indicates port to create a queue on.
+ * @startq: The starting FCP EQ to modify
+ *
+ * This function sends an MODIFY_EQ_DELAY mailbox command to the HBA.
+ *
+ * The @phba struct is used to send mailbox command to HBA. The @startq
+ * is used to get the starting FCP EQ to change.
+ * This function is asynchronous and will wait for the mailbox
+ * command to finish before continuing.
+ *
+ * On success this function will return a zero. If unable to allocate enough
+ * memory this function will return -ENOMEM. If the queue create mailbox command
+ * fails this function will return -ENXIO.
+ **/
+uint32_t
+lpfc_modify_fcp_eq_delay(struct lpfc_hba *phba, uint16_t startq)
+{
+	struct lpfc_mbx_modify_eq_delay *eq_delay;
+	LPFC_MBOXQ_t *mbox;
+	struct lpfc_queue *eq;
+	int cnt, rc, length, status = 0;
+	uint32_t shdr_status, shdr_add_status;
+	int fcp_eqidx;
+	union lpfc_sli4_cfg_shdr *shdr;
+	uint16_t dmult;
+
+	if (startq >= phba->cfg_fcp_eq_count)
+		return 0;
+
+	mbox = mempool_alloc(phba->mbox_mem_pool, GFP_KERNEL);
+	if (!mbox)
+		return -ENOMEM;
+	length = (sizeof(struct lpfc_mbx_modify_eq_delay) -
+		  sizeof(struct lpfc_sli4_cfg_mhdr));
+	lpfc_sli4_config(phba, mbox, LPFC_MBOX_SUBSYSTEM_COMMON,
+			 LPFC_MBOX_OPCODE_MODIFY_EQ_DELAY,
+			 length, LPFC_SLI4_MBX_EMBED);
+	eq_delay = &mbox->u.mqe.un.eq_delay;
+
+	/* Calculate delay multiper from maximum interrupt per second */
+	dmult = LPFC_DMULT_CONST/phba->cfg_fcp_imax - 1;
+
+	cnt = 0;
+	for (fcp_eqidx = startq; fcp_eqidx < phba->cfg_fcp_eq_count;
+	    fcp_eqidx++) {
+		eq = phba->sli4_hba.fp_eq[fcp_eqidx];
+		if (!eq)
+			continue;
+		eq_delay->u.request.eq[cnt].eq_id = eq->queue_id;
+		eq_delay->u.request.eq[cnt].phase = 0;
+		eq_delay->u.request.eq[cnt].delay_multi = dmult;
+		cnt++;
+		if (cnt >= LPFC_MAX_EQ_DELAY)
+			break;
+	}
+	eq_delay->u.request.num_eq = cnt;
+
+	mbox->vport = phba->pport;
+	mbox->mbox_cmpl = lpfc_sli_def_mbox_cmpl;
+	mbox->context1 = NULL;
+	rc = lpfc_sli_issue_mbox(phba, mbox, MBX_POLL);
+	shdr = (union lpfc_sli4_cfg_shdr *) &eq_delay->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 || rc) {
+		lpfc_printf_log(phba, KERN_ERR, LOG_INIT,
+				"2512 MODIFY_EQ_DELAY mailbox failed with "
+				"status x%x add_status x%x, mbx status x%x\n",
+				shdr_status, shdr_add_status, rc);
+		status = -ENXIO;
+	}
+	mempool_free(mbox, phba->mbox_mem_pool);
+	return status;
+}
+
+/**
  * lpfc_eq_create - Create an Event Queue on the HBA
  * @phba: HBA structure that indicates port to create a queue on.
  * @eq: The queue structure to use to create the event queue.
diff --git a/drivers/scsi/lpfc/lpfc_sli4.h b/drivers/scsi/lpfc/lpfc_sli4.h
index a4a77080091b..ec756118c5c1 100644
--- a/drivers/scsi/lpfc/lpfc_sli4.h
+++ b/drivers/scsi/lpfc/lpfc_sli4.h
@@ -598,6 +598,7 @@ struct lpfc_queue *lpfc_sli4_queue_alloc(struct lpfc_hba *, uint32_t,
 			uint32_t);
 void lpfc_sli4_queue_free(struct lpfc_queue *);
 uint32_t lpfc_eq_create(struct lpfc_hba *, struct lpfc_queue *, uint16_t);
+uint32_t lpfc_modify_fcp_eq_delay(struct lpfc_hba *, uint16_t);
 uint32_t lpfc_cq_create(struct lpfc_hba *, struct lpfc_queue *,
 			struct lpfc_queue *, uint32_t, uint32_t);
 int32_t lpfc_mq_create(struct lpfc_hba *, struct lpfc_queue *,