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+.. SPDX-License-Identifier: GPL-2.0
+
+==============================================
+SMARTPQI - Microchip Smart Storage SCSI driver
+==============================================
+
+This file describes the smartpqi SCSI driver for Microchip
+(http://www.microchip.com) PQI controllers. The smartpqi driver
+is the next generation SCSI driver for Microchip Corp. The smartpqi
+driver is the first SCSI driver to implement the PQI queuing model.
+
+The smartpqi driver will replace the aacraid driver for Adaptec Series 9
+controllers. Customers running an older kernel (Pre-4.9) using an Adaptec
+Series 9 controller will have to configure the smartpqi driver or their
+volumes will not be added to the OS.
+
+For Microchip smartpqi controller support, enable the smartpqi driver
+when configuring the kernel.
+
+For more information on the PQI Queuing Interface, please see:
+
+- http://www.t10.org/drafts.htm
+- http://www.t10.org/members/w_pqi2.htm
+
+Supported devices
+=================
+<Controller names to be added as they become publicly available.>
+
+smartpqi specific entries in /sys
+=================================
+
+smartpqi host attributes
+------------------------
+  - /sys/class/scsi_host/host*/rescan
+  - /sys/class/scsi_host/host*/driver_version
+
+  The host rescan attribute is a write only attribute. Writing to this
+  attribute will trigger the driver to scan for new, changed, or removed
+  devices and notify the SCSI mid-layer of any changes detected.
+
+  The version attribute is read-only and will return the driver version
+  and the controller firmware version.
+  For example::
+
+              driver: 0.9.13-370
+              firmware: 0.01-522
+
+smartpqi sas device attributes
+------------------------------
+  HBA devices are added to the SAS transport layer. These attributes are
+  automatically added by the SAS transport layer.
+
+  /sys/class/sas_device/end_device-X:X/sas_address
+  /sys/class/sas_device/end_device-X:X/enclosure_identifier
+  /sys/class/sas_device/end_device-X:X/scsi_target_id
+
+smartpqi specific ioctls
+========================
+
+  For compatibility with applications written for the cciss protocol.
+
+  CCISS_DEREGDISK, CCISS_REGNEWDISK, CCISS_REGNEWD
+	The above three ioctls all do exactly the same thing, which is to cause the driver
+	to rescan for new devices.  This does exactly the same thing as writing to the
+	smartpqi specific host "rescan" attribute.
+
+  CCISS_GETPCIINFO
+	Returns PCI domain, bus, device and function and "board ID" (PCI subsystem ID).
+
+  CCISS_GETDRIVVER
+	Returns driver version in three bytes encoded as::
+
+	  (DRIVER_MAJOR << 28) | (DRIVER_MINOR << 24) | (DRIVER_RELEASE << 16) | DRIVER_REVISION;
+
+  CCISS_PASSTHRU
+	Allows "BMIC" and "CISS" commands to be passed through to the Smart Storage Array.
+	These are used extensively by the SSA Array Configuration Utility, SNMP storage
+	agents, etc.