diff options
Diffstat (limited to 'Documentation/scsi')
-rw-r--r-- | Documentation/scsi/00-INDEX | 2 | ||||
-rw-r--r-- | Documentation/scsi/aic79xx.txt | 2 | ||||
-rw-r--r-- | Documentation/scsi/aic7xxx.txt | 2 | ||||
-rw-r--r-- | Documentation/scsi/osst.txt | 2 | ||||
-rw-r--r-- | Documentation/scsi/st.txt | 4 | ||||
-rw-r--r-- | Documentation/scsi/ufs.txt | 133 |
6 files changed, 142 insertions, 3 deletions
diff --git a/Documentation/scsi/00-INDEX b/Documentation/scsi/00-INDEX index b48ded55b555..b7dd6502bec5 100644 --- a/Documentation/scsi/00-INDEX +++ b/Documentation/scsi/00-INDEX @@ -94,3 +94,5 @@ sym53c8xx_2.txt - info on second generation driver for sym53c8xx based adapters tmscsim.txt - info on driver for AM53c974 based adapters +ufs.txt + - info on Universal Flash Storage(UFS) and UFS host controller driver. diff --git a/Documentation/scsi/aic79xx.txt b/Documentation/scsi/aic79xx.txt index 64ac7093c872..e2d3273000d4 100644 --- a/Documentation/scsi/aic79xx.txt +++ b/Documentation/scsi/aic79xx.txt @@ -215,7 +215,7 @@ The following information is available in this file: INCORRECTLY CAN RENDER YOUR SYSTEM INOPERABLE. USE THEM WITH CAUTION. - Edit the file "modprobe.conf" in the directory /etc and add/edit a + Put a .conf file in the /etc/modprobe.d/ directory and add/edit a line containing 'options aic79xx aic79xx=[command[,command...]]' where 'command' is one or more of the following: ----------------------------------------------------------------- diff --git a/Documentation/scsi/aic7xxx.txt b/Documentation/scsi/aic7xxx.txt index 18f8d1905e6a..7c5d0223d444 100644 --- a/Documentation/scsi/aic7xxx.txt +++ b/Documentation/scsi/aic7xxx.txt @@ -190,7 +190,7 @@ The following information is available in this file: INCORRECTLY CAN RENDER YOUR SYSTEM INOPERABLE. USE THEM WITH CAUTION. - Edit the file "modprobe.conf" in the directory /etc and add/edit a + Put a .conf file in the /etc/modprobe.d directory and add/edit a line containing 'options aic7xxx aic7xxx=[command[,command...]]' where 'command' is one or more of the following: ----------------------------------------------------------------- diff --git a/Documentation/scsi/osst.txt b/Documentation/scsi/osst.txt index ad86c6d1e898..00c8ebb2fd18 100644 --- a/Documentation/scsi/osst.txt +++ b/Documentation/scsi/osst.txt @@ -66,7 +66,7 @@ recognized. If you want to have the module autoloaded on access to /dev/osst, you may add something like alias char-major-206 osst -to your /etc/modprobe.conf (before 2.6: modules.conf). +to a file under /etc/modprobe.d/ directory. You may find it convenient to create a symbolic link ln -s nosst0 /dev/tape diff --git a/Documentation/scsi/st.txt b/Documentation/scsi/st.txt index 691ca292c24d..685bf3582abe 100644 --- a/Documentation/scsi/st.txt +++ b/Documentation/scsi/st.txt @@ -390,6 +390,10 @@ MTSETDRVBUFFER MT_ST_SYSV sets the SYSV semantics (mode) MT_ST_NOWAIT enables immediate mode (i.e., don't wait for the command to finish) for some commands (e.g., rewind) + MT_ST_NOWAIT_EOF enables immediate filemark mode (i.e. when + writing a filemark, don't wait for it to complete). Please + see the BASICS note about MTWEOFI with respect to the + possible dangers of writing immediate filemarks. MT_ST_SILI enables setting the SILI bit in SCSI commands when reading in variable block mode to enhance performance when reading blocks shorter than the byte count; set this only diff --git a/Documentation/scsi/ufs.txt b/Documentation/scsi/ufs.txt new file mode 100644 index 000000000000..41a6164592aa --- /dev/null +++ b/Documentation/scsi/ufs.txt @@ -0,0 +1,133 @@ + Universal Flash Storage + ======================= + + +Contents +-------- + +1. Overview +2. UFS Architecture Overview + 2.1 Application Layer + 2.2 UFS Transport Protocol(UTP) layer + 2.3 UFS Interconnect(UIC) Layer +3. UFSHCD Overview + 3.1 UFS controller initialization + 3.2 UTP Transfer requests + 3.3 UFS error handling + 3.4 SCSI Error handling + + +1. Overview +----------- + +Universal Flash Storage(UFS) is a storage specification for flash devices. +It is aimed to provide a universal storage interface for both +embedded and removable flash memory based storage in mobile +devices such as smart phones and tablet computers. The specification +is defined by JEDEC Solid State Technology Association. UFS is based +on MIPI M-PHY physical layer standard. UFS uses MIPI M-PHY as the +physical layer and MIPI Unipro as the link layer. + +The main goals of UFS is to provide, + * Optimized performance: + For UFS version 1.0 and 1.1 the target performance is as follows, + Support for Gear1 is mandatory (rate A: 1248Mbps, rate B: 1457.6Mbps) + Support for Gear2 is optional (rate A: 2496Mbps, rate B: 2915.2Mbps) + Future version of the standard, + Gear3 (rate A: 4992Mbps, rate B: 5830.4Mbps) + * Low power consumption + * High random IOPs and low latency + + +2. UFS Architecture Overview +---------------------------- + +UFS has a layered communication architecture which is based on SCSI +SAM-5 architectural model. + +UFS communication architecture consists of following layers, + +2.1 Application Layer + + The Application layer is composed of UFS command set layer(UCS), + Task Manager and Device manager. The UFS interface is designed to be + protocol agnostic, however SCSI has been selected as a baseline + protocol for versions 1.0 and 1.1 of UFS protocol layer. + UFS supports subset of SCSI commands defined by SPC-4 and SBC-3. + * UCS: It handles SCSI commands supported by UFS specification. + * Task manager: It handles task management functions defined by the + UFS which are meant for command queue control. + * Device manager: It handles device level operations and device + configuration operations. Device level operations mainly involve + device power management operations and commands to Interconnect + layers. Device level configurations involve handling of query + requests which are used to modify and retrieve configuration + information of the device. + +2.2 UFS Transport Protocol(UTP) layer + + UTP layer provides services for + the higher layers through Service Access Points. UTP defines 3 + service access points for higher layers. + * UDM_SAP: Device manager service access point is exposed to device + manager for device level operations. These device level operations + are done through query requests. + * UTP_CMD_SAP: Command service access point is exposed to UFS command + set layer(UCS) to transport commands. + * UTP_TM_SAP: Task management service access point is exposed to task + manager to transport task management functions. + UTP transports messages through UFS protocol information unit(UPIU). + +2.3 UFS Interconnect(UIC) Layer + + UIC is the lowest layer of UFS layered architecture. It handles + connection between UFS host and UFS device. UIC consists of + MIPI UniPro and MIPI M-PHY. UIC provides 2 service access points + to upper layer, + * UIC_SAP: To transport UPIU between UFS host and UFS device. + * UIO_SAP: To issue commands to Unipro layers. + + +3. UFSHCD Overview +------------------ + +The UFS host controller driver is based on Linux SCSI Framework. +UFSHCD is a low level device driver which acts as an interface between +SCSI Midlayer and PCIe based UFS host controllers. + +The current UFSHCD implementation supports following functionality, + +3.1 UFS controller initialization + + The initialization module brings UFS host controller to active state + and prepares the controller to transfer commands/response between + UFSHCD and UFS device. + +3.2 UTP Transfer requests + + Transfer request handling module of UFSHCD receives SCSI commands + from SCSI Midlayer, forms UPIUs and issues the UPIUs to UFS Host + controller. Also, the module decodes, responses received from UFS + host controller in the form of UPIUs and intimates the SCSI Midlayer + of the status of the command. + +3.3 UFS error handling + + Error handling module handles Host controller fatal errors, + Device fatal errors and UIC interconnect layer related errors. + +3.4 SCSI Error handling + + This is done through UFSHCD SCSI error handling routines registered + with SCSI Midlayer. Examples of some of the error handling commands + issues by SCSI Midlayer are Abort task, Lun reset and host reset. + UFSHCD Routines to perform these tasks are registered with + SCSI Midlayer through .eh_abort_handler, .eh_device_reset_handler and + .eh_host_reset_handler. + +In this version of UFSHCD Query requests and power management +functionality are not implemented. + +UFS Specifications can be found at, +UFS - http://www.jedec.org/sites/default/files/docs/JESD220.pdf +UFSHCI - http://www.jedec.org/sites/default/files/docs/JESD223.pdf |