scsi: mpt3sas: Enable interrupt coalescing on high iops

Enable interrupt coalescing only on high iops queues.

In ioc config page 1, offset 0x14 (ProductSpecific field) is used to
determine interrupt coalescing enabled/disabled on per reply descriptor
post queue group(8) basis. If 31st bit is zero, then interrupt coalescing
is enabled for all reply descriptor post queues. If 31st bit is set to one,
then user can enable/disable interrupt coalescing on per reply descriptor
post queue group(8) basis. So to enable interrupt coalescing only on first
reply descriptor post queue group (i.e. on high iops queues), set bit 0 and
31.

This configuration should reset during driver unload or shutdown to the
default settings. For this, the driver takes copy of default ioc page 1 and
copies back the default or unmodified ioc page1 during unload and
shutdown. This means that on next driver load (e.g. if older version driver
is loaded by user), current modified changes on ioc page1 won't take
effect.

Signed-off-by: Suganath Prabu S <[e-mail]>
Signed-off-by: Martin K. Petersen <[e-mail]>

drivers/scsi/mpt3sas/mpi/mpi2_cnfg.h

···
 	U8                      PCIBusNum;                  /*0x0E */
 	U8                      PCIDomainSegment;           /*0x0F */
 	U32                     Reserved1;                  /*0x10 */
-	U32                     Reserved2;                  /*0x14 */
+	U32                     ProductSpecific;            /* 0x14 */
 } MPI2_CONFIG_PAGE_IOC_1,
 	*PTR_MPI2_CONFIG_PAGE_IOC_1,
 	Mpi2IOCPage1_t, *pMpi2IOCPage1_t;

drivers/scsi/mpt3sas/mpt3sas_base.c

···
 {
 	Mpi2ConfigReply_t mpi_reply;
 	u32 iounit_pg1_flags;
+	Mpi2IOCPage1_t ioc_pg1;
 
 	ioc->nvme_abort_timeout = 30;
 	mpt3sas_config_get_manufacturing_pg0(ioc, &mpi_reply, &ioc->manu_pg0);
···
 			ioc->nvme_abort_timeout = NVME_TASK_ABORT_MAX_TIMEOUT;
 		else
 			ioc->nvme_abort_timeout = ioc->manu_pg11.NVMeAbortTO;
+	}
+	if (ioc->high_iops_queues) {
+		mpt3sas_config_get_ioc_pg1(ioc, &mpi_reply, &ioc_pg1);
+		pr_info(
+		"%s Enable interrupt coalescing only for first reply queue group(8)\n",
+		ioc->name);
+		/* If 31st bit is zero then interrupt coalescing is enabled
+		 * for all reply descriptor post queues. If 31st bit is set
+		 * to one then user can enable/disable interrupt coalescing
+		 * on per reply descriptor post queue group(8) basis. So to
+		 * enable interrupt coalescing only on first reply descriptor
+		 * post queue group 31st bit and zeroth bit is enabled.
+		 */
+		ioc_pg1.ProductSpecific = cpu_to_le32(0x80000001);
+		mpt3sas_config_set_ioc_pg1(ioc, &mpi_reply, &ioc_pg1);
 	}
 
 	mpt3sas_config_get_bios_pg2(ioc, &mpi_reply, &ioc->bios_pg2);

drivers/scsi/mpt3sas/mpt3sas_base.h

···
 	Mpi2IOUnitPage0_t iounit_pg0;
 	Mpi2IOUnitPage1_t iounit_pg1;
 	Mpi2IOUnitPage8_t iounit_pg8;
+	Mpi2IOCPage1_t	ioc_pg1_copy;
 
 	struct _boot_device req_boot_device;
 	struct _boot_device req_alt_boot_device;
···
 int mpt3sas_config_set_sas_iounit_pg1(struct MPT3SAS_ADAPTER *ioc,
 	Mpi2ConfigReply_t *mpi_reply, Mpi2SasIOUnitPage1_t *config_page,
 	u16 sz);
+int mpt3sas_config_get_ioc_pg1(struct MPT3SAS_ADAPTER *ioc, Mpi2ConfigReply_t
+	*mpi_reply, Mpi2IOCPage1_t *config_page);
+int mpt3sas_config_set_ioc_pg1(struct MPT3SAS_ADAPTER *ioc, Mpi2ConfigReply_t
+	*mpi_reply, Mpi2IOCPage1_t *config_page);
 int mpt3sas_config_get_ioc_pg8(struct MPT3SAS_ADAPTER *ioc, Mpi2ConfigReply_t
 	*mpi_reply, Mpi2IOCPage8_t *config_page);
 int mpt3sas_config_get_expander_pg0(struct MPT3SAS_ADAPTER *ioc,

drivers/scsi/mpt3sas/mpt3sas_config.c

···
  out:
 	return r;
 }
+/**
+ * mpt3sas_config_get_ioc_pg1 - obtain ioc page 1
+ * @ioc: per adapter object
+ * @mpi_reply: reply mf payload returned from firmware
+ * @config_page: contents of the config page
+ * Context: sleep.
+ *
+ * Return: 0 for success, non-zero for failure.
+ */
+int
+mpt3sas_config_get_ioc_pg1(struct MPT3SAS_ADAPTER *ioc,
+	Mpi2ConfigReply_t *mpi_reply, Mpi2IOCPage1_t *config_page)
+{
+	Mpi2ConfigRequest_t mpi_request;
+	int r;
+
+	memset(&mpi_request, 0, sizeof(Mpi2ConfigRequest_t));
+	mpi_request.Function = MPI2_FUNCTION_CONFIG;
+	mpi_request.Action = MPI2_CONFIG_ACTION_PAGE_HEADER;
+	mpi_request.Header.PageType = MPI2_CONFIG_PAGETYPE_IOC;
+	mpi_request.Header.PageNumber = 1;
+	mpi_request.Header.PageVersion = MPI2_IOCPAGE8_PAGEVERSION;
+	ioc->build_zero_len_sge_mpi(ioc, &mpi_request.PageBufferSGE);
+	r = _config_request(ioc, &mpi_request, mpi_reply,
+	    MPT3_CONFIG_PAGE_DEFAULT_TIMEOUT, NULL, 0);
+	if (r)
+		goto out;
+
+	mpi_request.Action = MPI2_CONFIG_ACTION_PAGE_READ_CURRENT;
+	r = _config_request(ioc, &mpi_request, mpi_reply,
+	    MPT3_CONFIG_PAGE_DEFAULT_TIMEOUT, config_page,
+	    sizeof(*config_page));
+ out:
+	return r;
+}
+
+/**
+ * mpt3sas_config_set_ioc_pg1 - modify ioc page 1
+ * @ioc: per adapter object
+ * @mpi_reply: reply mf payload returned from firmware
+ * @config_page: contents of the config page
+ * Context: sleep.
+ *
+ * Return: 0 for success, non-zero for failure.
+ */
+int
+mpt3sas_config_set_ioc_pg1(struct MPT3SAS_ADAPTER *ioc,
+	Mpi2ConfigReply_t *mpi_reply, Mpi2IOCPage1_t *config_page)
+{
+	Mpi2ConfigRequest_t mpi_request;
+	int r;
+
+	memset(&mpi_request, 0, sizeof(Mpi2ConfigRequest_t));
+	mpi_request.Function = MPI2_FUNCTION_CONFIG;
+	mpi_request.Action = MPI2_CONFIG_ACTION_PAGE_HEADER;
+	mpi_request.Header.PageType = MPI2_CONFIG_PAGETYPE_IOC;
+	mpi_request.Header.PageNumber = 1;
+	mpi_request.Header.PageVersion = MPI2_IOCPAGE8_PAGEVERSION;
+	ioc->build_zero_len_sge_mpi(ioc, &mpi_request.PageBufferSGE);
+	r = _config_request(ioc, &mpi_request, mpi_reply,
+	    MPT3_CONFIG_PAGE_DEFAULT_TIMEOUT, NULL, 0);
+	if (r)
+		goto out;
+
+	mpi_request.Action = MPI2_CONFIG_ACTION_PAGE_WRITE_CURRENT;
+	r = _config_request(ioc, &mpi_request, mpi_reply,
+	    MPT3_CONFIG_PAGE_DEFAULT_TIMEOUT, config_page,
+	    sizeof(*config_page));
+ out:
+	return r;
+}
 
 /**
  * mpt3sas_config_get_sas_device_pg0 - obtain sas device page 0

drivers/scsi/mpt3sas/mpt3sas_scsih.c

···
 	struct _pcie_device *pcie_device, *pcienext;
 	struct workqueue_struct	*wq;
 	unsigned long flags;
+	Mpi2ConfigReply_t mpi_reply;
 
 	ioc->remove_host = 1;
 
···
 	spin_unlock_irqrestore(&ioc->fw_event_lock, flags);
 	if (wq)
 		destroy_workqueue(wq);
-
+	/*
+	 * Copy back the unmodified ioc page1. so that on next driver load,
+	 * current modified changes on ioc page1 won't take effect.
+	 */
+	if (ioc->is_aero_ioc)
+		mpt3sas_config_set_ioc_pg1(ioc, &mpi_reply,
+				&ioc->ioc_pg1_copy);
 	/* release all the volumes */
 	_scsih_ir_shutdown(ioc);
 	sas_remove_host(shost);
···
 	struct MPT3SAS_ADAPTER *ioc = shost_priv(shost);
 	struct workqueue_struct	*wq;
 	unsigned long flags;
+	Mpi2ConfigReply_t mpi_reply;
 
 	ioc->remove_host = 1;
 
···
 	spin_unlock_irqrestore(&ioc->fw_event_lock, flags);
 	if (wq)
 		destroy_workqueue(wq);
+	/*
+	 * Copy back the unmodified ioc page1 so that on next driver load,
+	 * current modified changes on ioc page1 won't take effect.
+	 */
+	if (ioc->is_aero_ioc)
+		mpt3sas_config_set_ioc_pg1(ioc, &mpi_reply,
+				&ioc->ioc_pg1_copy);
 
 	_scsih_ir_shutdown(ioc);
 	mpt3sas_base_detach(ioc);