Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

4 files changed, 1144 insertions, 23 deletions

diff --git a/Documentation/scsi/ChangeLog.arcmsr b/Documentation/scsi/ChangeLog.arcmsr
new file mode 100644
index 00000000000..162c47fdf45
--- /dev/null
+++ b/Documentation/scsi/ChangeLog.arcmsr
@@ -0,0 +1,56 @@
+**************************************************************************
+** History
+**
+**   REV#         DATE             NAME         DESCRIPTION
+** 1.00.00.00    3/31/2004       Erich Chen     First release
+** 1.10.00.04    7/28/2004       Erich Chen     modify for ioctl
+** 1.10.00.06    8/28/2004       Erich Chen     modify for 2.6.x
+** 1.10.00.08    9/28/2004       Erich Chen     modify for x86_64
+** 1.10.00.10   10/10/2004       Erich Chen     bug fix for SMP & ioctl
+** 1.20.00.00   11/29/2004       Erich Chen     bug fix with arcmsr_bus_reset when PHY error
+** 1.20.00.02   12/09/2004       Erich Chen     bug fix with over 2T bytes RAID Volume
+** 1.20.00.04    1/09/2005       Erich Chen     fits for Debian linux kernel version 2.2.xx
+** 1.20.00.05    2/20/2005       Erich Chen     cleanly as look like a Linux driver at 2.6.x
+**                                              thanks for peoples kindness comment
+**						Kornel Wieliczek
+**						Christoph Hellwig
+**						Adrian Bunk
+**						Andrew Morton
+**						Christoph Hellwig
+**						James Bottomley
+**						Arjan van de Ven
+** 1.20.00.06    3/12/2005       Erich Chen     fix with arcmsr_pci_unmap_dma "unsigned long" cast,
+**						modify PCCB POOL allocated by "dma_alloc_coherent"
+**						(Kornel Wieliczek's comment)
+** 1.20.00.07    3/23/2005       Erich Chen     bug fix with arcmsr_scsi_host_template_init
+**						occur segmentation fault,
+**						if RAID adapter does not on PCI slot
+**						and modprobe/rmmod this driver twice.
+**						bug fix enormous stack usage (Adrian Bunk's comment)
+** 1.20.00.08    6/23/2005       Erich Chen     bug fix with abort command,
+**						in case of heavy loading when sata cable
+**						working on low quality connection
+** 1.20.00.09    9/12/2005       Erich Chen     bug fix with abort command handling, firmware version check
+**						and firmware update notify for hardware bug fix
+** 1.20.00.10    9/23/2005       Erich Chen     enhance sysfs function for change driver's max tag Q number.
+**						add DMA_64BIT_MASK for backward compatible with all 2.6.x
+**						add some useful message for abort command
+**						add ioctl code 'ARCMSR_IOCTL_FLUSH_ADAPTER_CACHE'
+**						customer can send this command for sync raid volume data
+** 1.20.00.11    9/29/2005       Erich Chen     by comment of Arjan van de Ven fix incorrect msleep redefine
+**						cast off sizeof(dma_addr_t) condition for 64bit pci_set_dma_mask
+** 1.20.00.12    9/30/2005       Erich Chen     bug fix with 64bit platform's ccbs using if over 4G system memory
+**						change 64bit pci_set_consistent_dma_mask into 32bit
+**						increcct adapter count if adapter initialize fail.
+**						miss edit at arcmsr_build_ccb....
+**						psge += sizeof(struct _SG64ENTRY *) =>
+**						psge += sizeof(struct _SG64ENTRY)
+**						64 bits sg entry would be incorrectly calculated
+**						thanks Kornel Wieliczek give me kindly notify
+**						and detail description
+** 1.20.00.13   11/15/2005       Erich Chen     scheduling pending ccb with FIFO
+**						change the architecture of arcmsr command queue list
+**						for linux standard list
+**						enable usage of pci message signal interrupt
+**						follow Randy.Danlup kindness suggestion cleanup this code
+**************************************************************************
\ No newline at end of file
diff --git a/Documentation/scsi/aacraid.txt b/Documentation/scsi/aacraid.txt
index be55670851a..ee03678c802 100644
--- a/Documentation/scsi/aacraid.txt
+++ b/Documentation/scsi/aacraid.txt
@@ -11,38 +11,43 @@ the original).
 Supported Cards/Chipsets
 -------------------------
 	PCI ID (pci.ids)	OEM	Product
-	9005:0285:9005:028a	Adaptec	2020ZCR (Skyhawk)
-	9005:0285:9005:028e	Adaptec	2020SA (Skyhawk)
-	9005:0285:9005:028b	Adaptec 2025ZCR (Terminator)
-	9005:0285:9005:028f	Adaptec 2025SA (Terminator)
-	9005:0285:9005:0286	Adaptec	2120S (Crusader)
-	9005:0286:9005:028d	Adaptec	2130S (Lancer)
+	9005:0283:9005:0283	Adaptec	Catapult (3210S with arc firmware)
+	9005:0284:9005:0284	Adaptec	Tomcat (3410S with arc firmware)
 	9005:0285:9005:0285	Adaptec	2200S (Vulcan)
+	9005:0285:9005:0286	Adaptec	2120S (Crusader)
 	9005:0285:9005:0287	Adaptec	2200S (Vulcan-2m)
+	9005:0285:9005:0288	Adaptec	3230S (Harrier)
+	9005:0285:9005:0289	Adaptec	3240S (Tornado)
+	9005:0285:9005:028a	Adaptec	2020ZCR (Skyhawk)
+	9005:0285:9005:028b	Adaptec 2025ZCR (Terminator)
 	9005:0286:9005:028c	Adaptec	2230S (Lancer)
 	9005:0286:9005:028c	Adaptec	2230SLP (Lancer)
-	9005:0285:9005:0296	Adaptec	2240S (SabreExpress)
+	9005:0286:9005:028d	Adaptec	2130S (Lancer)
+	9005:0285:9005:028e	Adaptec	2020SA (Skyhawk)
+	9005:0285:9005:028f	Adaptec 2025SA (Terminator)
 	9005:0285:9005:0290	Adaptec	2410SA (Jaguar)
-	9005:0285:9005:0293	Adaptec 21610SA (Corsair-16)
 	9005:0285:103c:3227	Adaptec 2610SA (Bearcat HP release)
+	9005:0285:9005:0293	Adaptec 21610SA (Corsair-16)
+	9005:0285:9005:0296	Adaptec	2240S (SabreExpress)
 	9005:0285:9005:0292	Adaptec	2810SA (Corsair-8)
 	9005:0285:9005:0294	Adaptec	Prowler
-	9005:0286:9005:029d	Adaptec	2420SA (Intruder HP release)
-	9005:0286:9005:029c	Adaptec	2620SA (Intruder)
-	9005:0286:9005:029b	Adaptec	2820SA (Intruder)
-	9005:0286:9005:02a7	Adaptec	2830SA (Skyray)
-	9005:0286:9005:02a8	Adaptec	2430SA (Skyray)
-	9005:0285:9005:0288	Adaptec	3230S (Harrier)
-	9005:0285:9005:0289	Adaptec	3240S (Tornado)
-	9005:0285:9005:0298	Adaptec	4000SAS (BlackBird)
 	9005:0285:9005:0297	Adaptec	4005SAS (AvonPark)
+	9005:0285:9005:0298	Adaptec	4000SAS (BlackBird)
 	9005:0285:9005:0299	Adaptec	4800SAS (Marauder-X)
 	9005:0285:9005:029a	Adaptec	4805SAS (Marauder-E)
+	9005:0286:9005:029b	Adaptec	2820SA (Intruder)
+	9005:0286:9005:029c	Adaptec	2620SA (Intruder)
+	9005:0286:9005:029d	Adaptec	2420SA (Intruder HP release)
 	9005:0286:9005:02a2	Adaptec	3800SAS (Hurricane44)
+	9005:0286:9005:02a7	Adaptec	3805SAS (Hurricane80)
+	9005:0286:9005:02a8	Adaptec	3400SAS (Hurricane40)
+	9005:0286:9005:02ac	Adaptec	1800SAS (Typhoon44)
+	9005:0286:9005:02b3	Adaptec	2400SAS (Hurricane40lm)
+	9005:0285:9005:02b5	Adaptec ASR5800 (Voodoo44)
+	9005:0285:9005:02b6	Adaptec ASR5805 (Voodoo80)
+	9005:0285:9005:02b7	Adaptec ASR5808 (Voodoo08)
 	1011:0046:9005:0364	Adaptec	5400S (Mustang)
 	1011:0046:9005:0365	Adaptec	5400S (Mustang)
-	9005:0283:9005:0283	Adaptec	Catapult (3210S with arc firmware)
-	9005:0284:9005:0284	Adaptec	Tomcat (3410S with arc firmware)
 	9005:0287:9005:0800	Adaptec	Themisto (Jupiter)
 	9005:0200:9005:0200	Adaptec	Themisto (Jupiter)
 	9005:0286:9005:0800	Adaptec	Callisto (Jupiter)
@@ -64,18 +69,20 @@ Supported Cards/Chipsets
 	9005:0285:9005:0290	IBM	ServeRAID 7t (Jaguar)
 	9005:0285:1014:02F2	IBM	ServeRAID 8i (AvonPark)
 	9005:0285:1014:0312	IBM	ServeRAID 8i (AvonParkLite)
-	9005:0286:1014:9580	IBM	ServeRAID 8k/8k-l8 (Aurora)
 	9005:0286:1014:9540	IBM	ServeRAID 8k/8k-l4 (AuroraLite)
-	9005:0286:9005:029f	ICP	ICP9014R0 (Lancer)
+	9005:0286:1014:9580	IBM	ServeRAID 8k/8k-l8 (Aurora)
+	9005:0286:1014:034d	IBM	ServeRAID 8s (Hurricane)
 	9005:0286:9005:029e	ICP	ICP9024R0 (Lancer)
+	9005:0286:9005:029f	ICP	ICP9014R0 (Lancer)
 	9005:0286:9005:02a0	ICP	ICP9047MA (Lancer)
 	9005:0286:9005:02a1	ICP	ICP9087MA (Lancer)
+	9005:0286:9005:02a3	ICP	ICP5445AU (Hurricane44)
 	9005:0286:9005:02a4	ICP	ICP9085LI (Marauder-X)
 	9005:0286:9005:02a5	ICP	ICP5085BR (Marauder-E)
-	9005:0286:9005:02a3	ICP	ICP5445AU (Hurricane44)
 	9005:0286:9005:02a6	ICP	ICP9067MA (Intruder-6)
-	9005:0286:9005:02a9	ICP	ICP5087AU (Skyray)
-	9005:0286:9005:02aa	ICP	ICP5047AU (Skyray)
+	9005:0286:9005:02a9	ICP	ICP5085AU (Hurricane80)
+	9005:0286:9005:02aa	ICP	ICP5045AU (Hurricane40)
+	9005:0286:9005:02b4	ICP	ICP5045AL (Hurricane40lm)
 
 People
 -------------------------
diff --git a/Documentation/scsi/arcmsr_spec.txt b/Documentation/scsi/arcmsr_spec.txt
new file mode 100644
index 00000000000..5e0042340fd
--- /dev/null
+++ b/Documentation/scsi/arcmsr_spec.txt
@@ -0,0 +1,574 @@
+*******************************************************************************
+**                            ARECA FIRMWARE SPEC
+*******************************************************************************
+**	Usage of IOP331 adapter
+**	(All In/Out is in IOP331's view)
+**	1. Message 0 --> InitThread message and retrun code
+**	2. Doorbell is used for RS-232 emulation
+**		inDoorBell :    bit0 -- data in ready
+**			(DRIVER DATA WRITE OK)
+**				bit1 -- data out has been read
+**			(DRIVER DATA READ OK)
+**		outDooeBell:    bit0 -- data out ready
+**			(IOP331 DATA WRITE OK)
+**				bit1 -- data in has been read
+**			(IOP331 DATA READ OK)
+**	3. Index Memory Usage
+**	offset 0xf00 : for RS232 out (request buffer)
+**	offset 0xe00 : for RS232 in  (scratch buffer)
+**	offset 0xa00 : for inbound message code message_rwbuffer
+**			(driver send to IOP331)
+**	offset 0xa00 : for outbound message code message_rwbuffer
+**			(IOP331 send to driver)
+**	4. RS-232 emulation
+**		Currently 128 byte buffer is used
+**			1st uint32_t : Data length (1--124)
+**			Byte 4--127  : Max 124 bytes of data
+**	5. PostQ
+**	All SCSI Command must be sent through postQ:
+**	(inbound queue port)	Request frame must be 32 bytes aligned
+**	#bit27--bit31 => flag for post ccb
+**	#bit0--bit26  => real address (bit27--bit31) of post arcmsr_cdb
+**		bit31 :
+**			0 : 256 bytes frame
+**			1 : 512 bytes frame
+**		bit30 :
+**			0 : normal request
+**			1 : BIOS request
+**		bit29 : reserved
+**		bit28 : reserved
+**		bit27 : reserved
+**  ---------------------------------------------------------------------------
+**	(outbount queue port)	Request reply
+**	#bit27--bit31
+**		=> flag for reply
+**	#bit0--bit26
+**		=> real address (bit27--bit31) of reply arcmsr_cdb
+**			bit31 : must be 0 (for this type of reply)
+**			bit30 : reserved for BIOS handshake
+**			bit29 : reserved
+**			bit28 :
+**			0 : no error, ignore AdapStatus/DevStatus/SenseData
+**			1 : Error, error code in AdapStatus/DevStatus/SenseData
+**			bit27 : reserved
+**	6. BIOS request
+**		All BIOS request is the same with request from PostQ
+**		Except :
+**			Request frame is sent from configuration space
+**		offset: 0x78 : Request Frame (bit30 == 1)
+**		offset: 0x18 : writeonly to generate
+**					IRQ to IOP331
+**		Completion of request:
+**			(bit30 == 0, bit28==err flag)
+**	7. Definition of SGL entry (structure)
+**	8. Message1 Out - Diag Status Code (????)
+**	9. Message0 message code :
+**		0x00 : NOP
+**		0x01 : Get Config
+**		->offset 0xa00 :for outbound message code message_rwbuffer
+**		(IOP331 send to driver)
+**		Signature             0x87974060(4)
+**		Request len           0x00000200(4)
+**		numbers of queue      0x00000100(4)
+**		SDRAM Size            0x00000100(4)-->256 MB
+**		IDE Channels          0x00000008(4)
+**		vendor                40 bytes char
+**		model                  8 bytes char
+**		FirmVer               16 bytes char
+**		Device Map            16 bytes char
+**		FirmwareVersion DWORD <== Added for checking of
+**						new firmware capability
+**		0x02 : Set Config
+**		->offset 0xa00 :for inbound message code message_rwbuffer
+**		(driver send to IOP331)
+**		Signature             0x87974063(4)
+**		UPPER32 of Request Frame  (4)-->Driver Only
+**		0x03 : Reset (Abort all queued Command)
+**		0x04 : Stop Background Activity
+**		0x05 : Flush Cache
+**		0x06 : Start Background Activity
+**			(re-start if background is halted)
+**		0x07 : Check If Host Command Pending
+**			(Novell May Need This Function)
+**		0x08 : Set controller time
+**		->offset 0xa00 : for inbound message code message_rwbuffer
+**		(driver to IOP331)
+**		byte 0 : 0xaa <-- signature
+**		byte 1 : 0x55 <-- signature
+**		byte 2 : year (04)
+**		byte 3 : month (1..12)
+**		byte 4 : date (1..31)
+**		byte 5 : hour (0..23)
+**		byte 6 : minute (0..59)
+**		byte 7 : second (0..59)
+*******************************************************************************
+*******************************************************************************
+**      	RS-232 Interface for Areca Raid Controller
+**      The low level command interface is exclusive with VT100 terminal
+**  --------------------------------------------------------------------
+**      1. Sequence of command execution
+**  --------------------------------------------------------------------
+**    	(A) Header : 3 bytes sequence (0x5E, 0x01, 0x61)
+**    	(B) Command block : variable length of data including length,
+**    		command code, data and checksum byte
+**    	(C) Return data : variable length of data
+**  --------------------------------------------------------------------
+**    2. Command block
+**  --------------------------------------------------------------------
+**    	(A) 1st byte : command block length (low byte)
+**    	(B) 2nd byte : command block length (high byte)
+**                note ..command block length shouldn't > 2040 bytes,
+**    		length excludes these two bytes
+**    	(C) 3rd byte : command code
+**    	(D) 4th and following bytes : variable length data bytes
+**    		depends on command code
+**    	(E) last byte : checksum byte (sum of 1st byte until last data byte)
+**  --------------------------------------------------------------------
+**    3. Command code and associated data
+**  --------------------------------------------------------------------
+**    	The following are command code defined in raid controller Command
+**    	code 0x10--0x1? are used for system level management,
+**    	no password checking is needed and should be implemented in separate
+**    	well controlled utility and not for end user access.
+**    	Command code 0x20--0x?? always check the password,
+**    	password must be entered to enable these command.
+**    	enum
+**    	{
+**    		GUI_SET_SERIAL=0x10,
+**    		GUI_SET_VENDOR,
+**    		GUI_SET_MODEL,
+**    		GUI_IDENTIFY,
+**    		GUI_CHECK_PASSWORD,
+**    		GUI_LOGOUT,
+**    		GUI_HTTP,
+**    		GUI_SET_ETHERNET_ADDR,
+**    		GUI_SET_LOGO,
+**    		GUI_POLL_EVENT,
+**    		GUI_GET_EVENT,
+**    		GUI_GET_HW_MONITOR,
+**    		//    GUI_QUICK_CREATE=0x20, (function removed)
+**    		GUI_GET_INFO_R=0x20,
+**    		GUI_GET_INFO_V,
+**    		GUI_GET_INFO_P,
+**    		GUI_GET_INFO_S,
+**    		GUI_CLEAR_EVENT,
+**    		GUI_MUTE_BEEPER=0x30,
+**    		GUI_BEEPER_SETTING,
+**    		GUI_SET_PASSWORD,
+**    		GUI_HOST_INTERFACE_MODE,
+**    		GUI_REBUILD_PRIORITY,
+**    		GUI_MAX_ATA_MODE,
+**    		GUI_RESET_CONTROLLER,
+**    		GUI_COM_PORT_SETTING,
+**    		GUI_NO_OPERATION,
+**    		GUI_DHCP_IP,
+**    		GUI_CREATE_PASS_THROUGH=0x40,
+**    		GUI_MODIFY_PASS_THROUGH,
+**    		GUI_DELETE_PASS_THROUGH,
+**    		GUI_IDENTIFY_DEVICE,
+**    		GUI_CREATE_RAIDSET=0x50,
+**    		GUI_DELETE_RAIDSET,
+**    		GUI_EXPAND_RAIDSET,
+**    		GUI_ACTIVATE_RAIDSET,
+**    		GUI_CREATE_HOT_SPARE,
+**    		GUI_DELETE_HOT_SPARE,
+**    		GUI_CREATE_VOLUME=0x60,
+**    		GUI_MODIFY_VOLUME,
+**    		GUI_DELETE_VOLUME,
+**    		GUI_START_CHECK_VOLUME,
+**    		GUI_STOP_CHECK_VOLUME
+**    	};
+**    Command description :
+**    	GUI_SET_SERIAL : Set the controller serial#
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x10
+**    		byte 3          : password length (should be 0x0f)
+**    		byte 4-0x13     : should be "ArEcATecHnoLogY"
+**    		byte 0x14--0x23 : Serial number string (must be 16 bytes)
+**      GUI_SET_VENDOR : Set vendor string for the controller
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x11
+**    		byte 3          : password length (should be 0x08)
+**    		byte 4-0x13     : should be "ArEcAvAr"
+**    		byte 0x14--0x3B : vendor string (must be 40 bytes)
+**      GUI_SET_MODEL : Set the model name of the controller
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x12
+**    		byte 3          : password length (should be 0x08)
+**    		byte 4-0x13     : should be "ArEcAvAr"
+**    		byte 0x14--0x1B : model string (must be 8 bytes)
+**      GUI_IDENTIFY : Identify device
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x13
+**    		                  return "Areca RAID Subsystem "
+**      GUI_CHECK_PASSWORD : Verify password
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x14
+**    		byte 3          : password length
+**    		byte 4-0x??     : user password to be checked
+**      GUI_LOGOUT : Logout GUI (force password checking on next command)
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x15
+**      GUI_HTTP : HTTP interface (reserved for Http proxy service)(0x16)
+**
+**      GUI_SET_ETHERNET_ADDR : Set the ethernet MAC address
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x17
+**    		byte 3          : password length (should be 0x08)
+**    		byte 4-0x13     : should be "ArEcAvAr"
+**    		byte 0x14--0x19 : Ethernet MAC address (must be 6 bytes)
+**      GUI_SET_LOGO : Set logo in HTTP
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x18
+**    		byte 3          : Page# (0/1/2/3) (0xff --> clear OEM logo)
+**    		byte 4/5/6/7    : 0x55/0xaa/0xa5/0x5a
+**    		byte 8          : TITLE.JPG data (each page must be 2000 bytes)
+**    		                  note page0 1st 2 byte must be
+**    					actual length of the JPG file
+**      GUI_POLL_EVENT : Poll If Event Log Changed
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x19
+**      GUI_GET_EVENT : Read Event
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x1a
+**    		byte 3          : Event Page (0:1st page/1/2/3:last page)
+**      GUI_GET_HW_MONITOR : Get HW monitor data
+**    		byte 0,1        : length
+**    		byte 2 			: command code 0x1b
+**    		byte 3 			: # of FANs(example 2)
+**    		byte 4 			: # of Voltage sensor(example 3)
+**    		byte 5 			: # of temperature sensor(example 2)
+**    		byte 6 			: # of power
+**    		byte 7/8        : Fan#0 (RPM)
+**    		byte 9/10       : Fan#1
+**    		byte 11/12 		: Voltage#0 original value in *1000
+**    		byte 13/14 		: Voltage#0 value
+**    		byte 15/16 		: Voltage#1 org
+**    		byte 17/18 		: Voltage#1
+**    		byte 19/20 		: Voltage#2 org
+**    		byte 21/22 		: Voltage#2
+**    		byte 23 		: Temp#0
+**    		byte 24 		: Temp#1
+**    		byte 25 		: Power indicator (bit0 : power#0,
+**    						 bit1 : power#1)
+**    		byte 26 		: UPS indicator
+**      GUI_QUICK_CREATE : Quick create raid/volume set
+**    	    byte 0,1        : length
+**    	    byte 2          : command code 0x20
+**    	    byte 3/4/5/6    : raw capacity
+**    	    byte 7 			: raid level
+**    	    byte 8 			: stripe size
+**    	    byte 9 			: spare
+**    	    byte 10/11/12/13: device mask (the devices to create raid/volume)
+**    		This function is removed, application like
+**    		to implement quick create function
+**    	need to use GUI_CREATE_RAIDSET and GUI_CREATE_VOLUMESET function.
+**      GUI_GET_INFO_R : Get Raid Set Information
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x20
+**    		byte 3          : raidset#
+**    	typedef struct sGUI_RAIDSET
+**    	{
+**    		BYTE grsRaidSetName[16];
+**    		DWORD grsCapacity;
+**    		DWORD grsCapacityX;
+**    		DWORD grsFailMask;
+**    		BYTE grsDevArray[32];
+**    		BYTE grsMemberDevices;
+**    		BYTE grsNewMemberDevices;
+**    		BYTE grsRaidState;
+**    		BYTE grsVolumes;
+**    		BYTE grsVolumeList[16];
+**    		BYTE grsRes1;
+**    		BYTE grsRes2;
+**    		BYTE grsRes3;
+**    		BYTE grsFreeSegments;
+**    		DWORD grsRawStripes[8];
+**    		DWORD grsRes4;
+**    		DWORD grsRes5; //     Total to 128 bytes
+**    		DWORD grsRes6; //     Total to 128 bytes
+**    	} sGUI_RAIDSET, *pGUI_RAIDSET;
+**      GUI_GET_INFO_V : Get Volume Set Information
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x21
+**    		byte 3          : volumeset#
+**    	typedef struct sGUI_VOLUMESET
+**    	{
+**    		BYTE gvsVolumeName[16]; //     16
+**    		DWORD gvsCapacity;
+**    		DWORD gvsCapacityX;
+**    		DWORD gvsFailMask;
+**    		DWORD gvsStripeSize;
+**    		DWORD gvsNewFailMask;
+**    		DWORD gvsNewStripeSize;
+**    		DWORD gvsVolumeStatus;
+**    		DWORD gvsProgress; //     32
+**    		sSCSI_ATTR gvsScsi;
+**    		BYTE gvsMemberDisks;
+**    		BYTE gvsRaidLevel; //     8
+**    		BYTE gvsNewMemberDisks;
+**    		BYTE gvsNewRaidLevel;
+**    		BYTE gvsRaidSetNumber;
+**    		BYTE gvsRes0; //     4
+**    		BYTE gvsRes1[4]; //     64 bytes
+**    	} sGUI_VOLUMESET, *pGUI_VOLUMESET;
+**      GUI_GET_INFO_P : Get Physical Drive Information
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x22
+**    		byte 3          : drive # (from 0 to max-channels - 1)
+**    	typedef struct sGUI_PHY_DRV
+**    	{
+**    		BYTE gpdModelName[40];
+**    		BYTE gpdSerialNumber[20];
+**    		BYTE gpdFirmRev[8];
+**    		DWORD gpdCapacity;
+**    		DWORD gpdCapacityX; //     Reserved for expansion
+**    		BYTE gpdDeviceState;
+**    		BYTE gpdPioMode;
+**    		BYTE gpdCurrentUdmaMode;
+**    		BYTE gpdUdmaMode;
+**    		BYTE gpdDriveSelect;
+**    		BYTE gpdRaidNumber; //     0xff if not belongs to a raid set
+**    		sSCSI_ATTR gpdScsi;
+**    		BYTE gpdReserved[40]; //     Total to 128 bytes
+**    	} sGUI_PHY_DRV, *pGUI_PHY_DRV;
+**    	GUI_GET_INFO_S : Get System Information
+**      	byte 0,1        : length
+**      	byte 2          : command code 0x23
+**    	typedef struct sCOM_ATTR
+**    	{
+**    		BYTE comBaudRate;
+**    		BYTE comDataBits;
+**    		BYTE comStopBits;
+**    		BYTE comParity;
+**    		BYTE comFlowControl;
+**    	} sCOM_ATTR, *pCOM_ATTR;
+**    	typedef struct sSYSTEM_INFO
+**    	{
+**    		BYTE gsiVendorName[40];
+**    		BYTE gsiSerialNumber[16];
+**    		BYTE gsiFirmVersion[16];
+**    		BYTE gsiBootVersion[16];
+**    		BYTE gsiMbVersion[16];
+**    		BYTE gsiModelName[8];
+**    		BYTE gsiLocalIp[4];
+**    		BYTE gsiCurrentIp[4];
+**    		DWORD gsiTimeTick;
+**    		DWORD gsiCpuSpeed;
+**    		DWORD gsiICache;
+**    		DWORD gsiDCache;
+**    		DWORD gsiScache;
+**    		DWORD gsiMemorySize;
+**    		DWORD gsiMemorySpeed;
+**    		DWORD gsiEvents;
+**    		BYTE gsiMacAddress[6];
+**    		BYTE gsiDhcp;
+**    		BYTE gsiBeeper;
+**    		BYTE gsiChannelUsage;
+**    		BYTE gsiMaxAtaMode;
+**    		BYTE gsiSdramEcc; //     1:if ECC enabled
+**    		BYTE gsiRebuildPriority;
+**    		sCOM_ATTR gsiComA; //     5 bytes
+**    		sCOM_ATTR gsiComB; //     5 bytes
+**    		BYTE gsiIdeChannels;
+**    		BYTE gsiScsiHostChannels;
+**    		BYTE gsiIdeHostChannels;
+**    		BYTE gsiMaxVolumeSet;
+**    		BYTE gsiMaxRaidSet;
+**    		BYTE gsiEtherPort; //     1:if ether net port supported
+**    		BYTE gsiRaid6Engine; //     1:Raid6 engine supported
+**    		BYTE gsiRes[75];
+**    	} sSYSTEM_INFO, *pSYSTEM_INFO;
+**    	GUI_CLEAR_EVENT : Clear System Event
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x24
+**      GUI_MUTE_BEEPER : Mute current beeper
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x30
+**      GUI_BEEPER_SETTING : Disable beeper
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x31
+**    		byte 3          : 0->disable, 1->enable
+**      GUI_SET_PASSWORD : Change password
+**    		byte 0,1        : length
+**    		byte 2 			: command code 0x32
+**    		byte 3 			: pass word length ( must <= 15 )
+**    		byte 4 			: password (must be alpha-numerical)
+**    	GUI_HOST_INTERFACE_MODE : Set host interface mode
+**    		byte 0,1        : length
+**    		byte 2 			: command code 0x33
+**    		byte 3 			: 0->Independent, 1->cluster
+**      GUI_REBUILD_PRIORITY : Set rebuild priority
+**    		byte 0,1        : length
+**    		byte 2 			: command code 0x34
+**    		byte 3 			: 0/1/2/3 (low->high)
+**      GUI_MAX_ATA_MODE : Set maximum ATA mode to be used
+**    		byte 0,1        : length
+**    		byte 2 			: command code 0x35
+**    		byte 3 			: 0/1/2/3 (133/100/66/33)
+**      GUI_RESET_CONTROLLER : Reset Controller
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x36
+**                            *Response with VT100 screen (discard it)
+**      GUI_COM_PORT_SETTING : COM port setting
+**    		byte 0,1        : length
+**    		byte 2 			: command code 0x37
+**    		byte 3 			: 0->COMA (term port),
+**    					  1->COMB (debug port)
+**    		byte 4 			: 0/1/2/3/4/5/6/7
+**    			(1200/2400/4800/9600/19200/38400/57600/115200)
+**    		byte 5 			: data bit
+**    					(0:7 bit, 1:8 bit : must be 8 bit)
+**    		byte 6 			: stop bit (0:1, 1:2 stop bits)
+**    		byte 7 			: parity (0:none, 1:off, 2:even)
+**    		byte 8 			: flow control
+**    			(0:none, 1:xon/xoff, 2:hardware => must use none)
+**      GUI_NO_OPERATION : No operation
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x38
+**      GUI_DHCP_IP : Set DHCP option and local IP address
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x39
+**    		byte 3          : 0:dhcp disabled, 1:dhcp enabled
+**    		byte 4/5/6/7    : IP address
+**      GUI_CREATE_PASS_THROUGH : Create pass through disk
+**    		byte 0,1        : length
+**    		byte 2 			: command code 0x40
+**    		byte 3 			: device #
+**    		byte 4 			: scsi channel (0/1)
+**    		byte 5 			: scsi id (0-->15)
+**    		byte 6 			: scsi lun (0-->7)
+**    		byte 7 			: tagged queue (1 : enabled)
+**    		byte 8 			: cache mode (1 : enabled)
+**    		byte 9 			: max speed (0/1/2/3/4,
+**    			async/20/40/80/160 for scsi)
+**    			(0/1/2/3/4, 33/66/100/133/150 for ide  )
+**      GUI_MODIFY_PASS_THROUGH : Modify pass through disk
+**    		byte 0,1        : length
+**    		byte 2 			: command code 0x41
+**    		byte 3 			: device #
+**    		byte 4 			: scsi channel (0/1)
+**    		byte 5 			: scsi id (0-->15)
+**    		byte 6 			: scsi lun (0-->7)
+**    		byte 7 			: tagged queue (1 : enabled)
+**    		byte 8 			: cache mode (1 : enabled)
+**    		byte 9 			: max speed (0/1/2/3/4,
+**    					async/20/40/80/160 for scsi)
+**    			(0/1/2/3/4, 33/66/100/133/150 for ide  )
+**      GUI_DELETE_PASS_THROUGH : Delete pass through disk
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x42
+**    		byte 3          : device# to be deleted
+**      GUI_IDENTIFY_DEVICE : Identify Device
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x43
+**    		byte 3          : Flash Method
+**    				(0:flash selected, 1:flash not selected)
+**    		byte 4/5/6/7    : IDE device mask to be flashed
+**                           note .... no response data available
+**    	GUI_CREATE_RAIDSET : Create Raid Set
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x50
+**    		byte 3/4/5/6    : device mask
+**    		byte 7-22       : raidset name (if byte 7 == 0:use default)
+**      GUI_DELETE_RAIDSET : Delete Raid Set
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x51
+**    		byte 3          : raidset#
+**    	GUI_EXPAND_RAIDSET : Expand Raid Set
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x52
+**    		byte 3          : raidset#
+**    		byte 4/5/6/7    : device mask for expansion
+**    		byte 8/9/10     : (8:0 no change, 1 change, 0xff:terminate,
+**    				9:new raid level,
+**    				10:new stripe size
+**    				0/1/2/3/4/5->4/8/16/32/64/128K )
+**    		byte 11/12/13   : repeat for each volume in the raidset
+**      GUI_ACTIVATE_RAIDSET : Activate incomplete raid set
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x53
+**    		byte 3          : raidset#
+**      GUI_CREATE_HOT_SPARE : Create hot spare disk
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x54
+**    		byte 3/4/5/6    : device mask for hot spare creation
+**    	GUI_DELETE_HOT_SPARE : Delete hot spare disk
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x55
+**    		byte 3/4/5/6    : device mask for hot spare deletion
+**    	GUI_CREATE_VOLUME : Create volume set
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x60
+**    		byte 3          : raidset#
+**    		byte 4-19       : volume set name
+**    				(if byte4 == 0, use default)
+**    		byte 20-27      : volume capacity (blocks)
+**    		byte 28 		: raid level
+**    		byte 29 		: stripe size
+**    				(0/1/2/3/4/5->4/8/16/32/64/128K)
+**    		byte 30 		: channel
+**    		byte 31 		: ID
+**    		byte 32 		: LUN
+**    		byte 33 		: 1 enable tag
+**    		byte 34 		: 1 enable cache
+**    		byte 35 		: speed
+**    		(0/1/2/3/4->async/20/40/80/160 for scsi)
+**    		(0/1/2/3/4->33/66/100/133/150 for IDE  )
+**    		byte 36 		: 1 to select quick init
+**
+**    	GUI_MODIFY_VOLUME : Modify volume Set
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x61
+**    		byte 3          : volumeset#
+**    		byte 4-19       : new volume set name
+**    		(if byte4 == 0, not change)
+**    		byte 20-27      : new volume capacity (reserved)
+**    		byte 28 		: new raid level
+**    		byte 29 		: new stripe size
+**    		(0/1/2/3/4/5->4/8/16/32/64/128K)
+**    		byte 30 		: new channel
+**    		byte 31 		: new ID
+**    		byte 32 		: new LUN
+**    		byte 33 		: 1 enable tag
+**    		byte 34 		: 1 enable cache
+**    		byte 35 		: speed
+**    		(0/1/2/3/4->async/20/40/80/160 for scsi)
+**    		(0/1/2/3/4->33/66/100/133/150 for IDE  )
+**    	GUI_DELETE_VOLUME : Delete volume set
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x62
+**    		byte 3          : volumeset#
+**    	GUI_START_CHECK_VOLUME : Start volume consistency check
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x63
+**    		byte 3          : volumeset#
+**    	GUI_STOP_CHECK_VOLUME : Stop volume consistency check
+**    		byte 0,1        : length
+**    		byte 2          : command code 0x64
+** ---------------------------------------------------------------------
+**    4. Returned data
+** ---------------------------------------------------------------------
+**    	(A) Header          : 3 bytes sequence (0x5E, 0x01, 0x61)
+**    	(B) Length          : 2 bytes
+**    			(low byte 1st, excludes length and checksum byte)
+**    	(C) status or data  :
+**           <1> If length == 1 ==> 1 byte status code
+**    		#define GUI_OK                    0x41
+**    		#define GUI_RAIDSET_NOT_NORMAL    0x42
+**    		#define GUI_VOLUMESET_NOT_NORMAL  0x43
+**    		#define GUI_NO_RAIDSET            0x44
+**    		#define GUI_NO_VOLUMESET          0x45
+**    		#define GUI_NO_PHYSICAL_DRIVE     0x46
+**    		#define GUI_PARAMETER_ERROR       0x47
+**    		#define GUI_UNSUPPORTED_COMMAND   0x48
+**    		#define GUI_DISK_CONFIG_CHANGED   0x49
+**    		#define GUI_INVALID_PASSWORD      0x4a
+**    		#define GUI_NO_DISK_SPACE         0x4b
+**    		#define GUI_CHECKSUM_ERROR        0x4c
+**    		#define GUI_PASSWORD_REQUIRED     0x4d
+**           <2> If length > 1 ==>
+**    		data block returned from controller
+**    		and the contents depends on the command code
+**    	(E) Checksum        : checksum of length and status or data byte
+**************************************************************************
diff --git a/Documentation/scsi/libsas.txt b/Documentation/scsi/libsas.txt
new file mode 100644
index 00000000000..9e2078b2a61
--- /dev/null
+++ b/Documentation/scsi/libsas.txt
@@ -0,0 +1,484 @@
+SAS Layer
+---------
+
+The SAS Layer is a management infrastructure which manages
+SAS LLDDs.  It sits between SCSI Core and SAS LLDDs.  The
+layout is as follows: while SCSI Core is concerned with
+SAM/SPC issues, and a SAS LLDD+sequencer is concerned with
+phy/OOB/link management, the SAS layer is concerned with:
+
+      * SAS Phy/Port/HA event management (LLDD generates,
+        SAS Layer processes),
+      * SAS Port management (creation/destruction),
+      * SAS Domain discovery and revalidation,
+      * SAS Domain device management,
+      * SCSI Host registration/unregistration,
+      * Device registration with SCSI Core (SAS) or libata
+        (SATA), and
+      * Expander management and exporting expander control
+        to user space.
+
+A SAS LLDD is a PCI device driver.  It is concerned with
+phy/OOB management, and vendor specific tasks and generates
+events to the SAS layer.
+
+The SAS Layer does most SAS tasks as outlined in the SAS 1.1
+spec.
+
+The sas_ha_struct describes the SAS LLDD to the SAS layer.
+Most of it is used by the SAS Layer but a few fields need to
+be initialized by the LLDDs.
+
+After initializing your hardware, from the probe() function
+you call sas_register_ha(). It will register your LLDD with
+the SCSI subsystem, creating a SCSI host and it will
+register your SAS driver with the sysfs SAS tree it creates.
+It will then return.  Then you enable your phys to actually
+start OOB (at which point your driver will start calling the
+notify_* event callbacks).
+
+Structure descriptions:
+
+struct sas_phy --------------------
+Normally this is statically embedded to your driver's
+phy structure:
+	struct my_phy {
+	       blah;
+	       struct sas_phy sas_phy;
+	       bleh;
+	};
+And then all the phys are an array of my_phy in your HA
+struct (shown below).
+
+Then as you go along and initialize your phys you also
+initialize the sas_phy struct, along with your own
+phy structure.
+
+In general, the phys are managed by the LLDD and the ports
+are managed by the SAS layer.  So the phys are initialized
+and updated by the LLDD and the ports are initialized and
+updated by the SAS layer.
+
+There is a scheme where the LLDD can RW certain fields,
+and the SAS layer can only read such ones, and vice versa.
+The idea is to avoid unnecessary locking.
+
+enabled -- must be set (0/1)
+id -- must be set [0,MAX_PHYS)
+class, proto, type, role, oob_mode, linkrate -- must be set
+oob_mode --  you set this when OOB has finished and then notify
+the SAS Layer.
+
+sas_addr -- this normally points to an array holding the sas
+address of the phy, possibly somewhere in your my_phy
+struct.
+
+attached_sas_addr -- set this when you (LLDD) receive an
+IDENTIFY frame or a FIS frame, _before_ notifying the SAS
+layer.  The idea is that sometimes the LLDD may want to fake
+or provide a different SAS address on that phy/port and this
+allows it to do this.  At best you should copy the sas
+address from the IDENTIFY frame or maybe generate a SAS
+address for SATA directly attached devices.  The Discover
+process may later change this.
+
+frame_rcvd -- this is where you copy the IDENTIFY/FIS frame
+when you get it; you lock, copy, set frame_rcvd_size and
+unlock the lock, and then call the event.  It is a pointer
+since there's no way to know your hw frame size _exactly_,
+so you define the actual array in your phy struct and let
+this pointer point to it.  You copy the frame from your
+DMAable memory to that area holding the lock.
+
+sas_prim -- this is where primitives go when they're
+received.  See sas.h. Grab the lock, set the primitive,
+release the lock, notify.
+
+port -- this points to the sas_port if the phy belongs
+to a port -- the LLDD only reads this. It points to the
+sas_port this phy is part of.  Set by the SAS Layer.
+
+ha -- may be set; the SAS layer sets it anyway.
+
+lldd_phy -- you should set this to point to your phy so you
+can find your way around faster when the SAS layer calls one
+of your callbacks and passes you a phy.  If the sas_phy is
+embedded you can also use container_of -- whatever you
+prefer.
+
+
+struct sas_port --------------------
+The LLDD doesn't set any fields of this struct -- it only
+reads them.  They should be self explanatory.
+
+phy_mask is 32 bit, this should be enough for now, as I
+haven't heard of a HA having more than 8 phys.
+
+lldd_port -- I haven't found use for that -- maybe other
+LLDD who wish to have internal port representation can make
+use of this.
+
+
+struct sas_ha_struct --------------------
+It normally is statically declared in your own LLDD
+structure describing your adapter:
+struct my_sas_ha {
+       blah;
+       struct sas_ha_struct sas_ha;
+       struct my_phy phys[MAX_PHYS];
+       struct sas_port sas_ports[MAX_PHYS]; /* (1) */
+       bleh;
+};
+
+(1) If your LLDD doesn't have its own port representation.
+
+What needs to be initialized (sample function given below).
+
+pcidev
+sas_addr -- since the SAS layer doesn't want to mess with
+	 memory allocation, etc, this points to statically
+	 allocated array somewhere (say in your host adapter
+	 structure) and holds the SAS address of the host
+	 adapter as given by you or the manufacturer, etc.
+sas_port
+sas_phy -- an array of pointers to structures. (see
+	note above on sas_addr).
+	These must be set.  See more notes below.
+num_phys -- the number of phys present in the sas_phy array,
+	 and the number of ports present in the sas_port
+	 array.  There can be a maximum num_phys ports (one per
+	 port) so we drop the num_ports, and only use
+	 num_phys.
+
+The event interface:
+
+	/* LLDD calls these to notify the class of an event. */
+	void (*notify_ha_event)(struct sas_ha_struct *, enum ha_event);
+	void (*notify_port_event)(struct sas_phy *, enum port_event);
+	void (*notify_phy_event)(struct sas_phy *, enum phy_event);
+
+When sas_register_ha() returns, those are set and can be
+called by the LLDD to notify the SAS layer of such events
+the SAS layer.
+
+The port notification:
+
+	/* The class calls these to notify the LLDD of an event. */
+	void (*lldd_port_formed)(struct sas_phy *);
+	void (*lldd_port_deformed)(struct sas_phy *);
+
+If the LLDD wants notification when a port has been formed
+or deformed it sets those to a function satisfying the type.
+
+A SAS LLDD should also implement at least one of the Task
+Management Functions (TMFs) described in SAM:
+
+	/* Task Management Functions. Must be called from process context. */
+	int (*lldd_abort_task)(struct sas_task *);
+	int (*lldd_abort_task_set)(struct domain_device *, u8 *lun);
+	int (*lldd_clear_aca)(struct domain_device *, u8 *lun);
+	int (*lldd_clear_task_set)(struct domain_device *, u8 *lun);
+	int (*lldd_I_T_nexus_reset)(struct domain_device *);
+	int (*lldd_lu_reset)(struct domain_device *, u8 *lun);
+	int (*lldd_query_task)(struct sas_task *);
+
+For more information please read SAM from T10.org.
+
+Port and Adapter management:
+
+	/* Port and Adapter management */
+	int (*lldd_clear_nexus_port)(struct sas_port *);
+	int (*lldd_clear_nexus_ha)(struct sas_ha_struct *);
+
+A SAS LLDD should implement at least one of those.
+
+Phy management:
+
+	/* Phy management */
+	int (*lldd_control_phy)(struct sas_phy *, enum phy_func);
+
+lldd_ha -- set this to point to your HA struct. You can also
+use container_of if you embedded it as shown above.
+
+A sample initialization and registration function
+can look like this (called last thing from probe())
+*but* before you enable the phys to do OOB:
+
+static int register_sas_ha(struct my_sas_ha *my_ha)
+{
+	int i;
+	static struct sas_phy   *sas_phys[MAX_PHYS];
+	static struct sas_port  *sas_ports[MAX_PHYS];
+
+	my_ha->sas_ha.sas_addr = &my_ha->sas_addr[0];
+
+	for (i = 0; i < MAX_PHYS; i++) {
+		sas_phys[i] = &my_ha->phys[i].sas_phy;
+		sas_ports[i] = &my_ha->sas_ports[i];
+	}
+
+	my_ha->sas_ha.sas_phy  = sas_phys;
+	my_ha->sas_ha.sas_port = sas_ports;
+	my_ha->sas_ha.num_phys = MAX_PHYS;
+
+	my_ha->sas_ha.lldd_port_formed = my_port_formed;
+
+	my_ha->sas_ha.lldd_dev_found = my_dev_found;
+	my_ha->sas_ha.lldd_dev_gone = my_dev_gone;
+
+	my_ha->sas_ha.lldd_max_execute_num = lldd_max_execute_num; (1)
+
+	my_ha->sas_ha.lldd_queue_size = ha_can_queue;
+	my_ha->sas_ha.lldd_execute_task = my_execute_task;
+
+	my_ha->sas_ha.lldd_abort_task     = my_abort_task;
+	my_ha->sas_ha.lldd_abort_task_set = my_abort_task_set;
+	my_ha->sas_ha.lldd_clear_aca      = my_clear_aca;
+	my_ha->sas_ha.lldd_clear_task_set = my_clear_task_set;
+	my_ha->sas_ha.lldd_I_T_nexus_reset= NULL; (2)
+	my_ha->sas_ha.lldd_lu_reset       = my_lu_reset;
+	my_ha->sas_ha.lldd_query_task     = my_query_task;
+
+	my_ha->sas_ha.lldd_clear_nexus_port = my_clear_nexus_port;
+	my_ha->sas_ha.lldd_clear_nexus_ha = my_clear_nexus_ha;
+
+	my_ha->sas_ha.lldd_control_phy = my_control_phy;
+
+	return sas_register_ha(&my_ha->sas_ha);
+}
+
+(1) This is normally a LLDD parameter, something of the
+lines of a task collector.  What it tells the SAS Layer is
+whether the SAS layer should run in Direct Mode (default:
+value 0 or 1) or Task Collector Mode (value greater than 1).
+
+In Direct Mode, the SAS Layer calls Execute Task as soon as
+it has a command to send to the SDS, _and_ this is a single
+command, i.e. not linked.
+
+Some hardware (e.g. aic94xx) has the capability to DMA more
+than one task at a time (interrupt) from host memory.  Task
+Collector Mode is an optional feature for HAs which support
+this in their hardware.  (Again, it is completely optional
+even if your hardware supports it.)
+
+In Task Collector Mode, the SAS Layer would do _natural_
+coalescing of tasks and at the appropriate moment it would
+call your driver to DMA more than one task in a single HA
+interrupt. DMBS may want to use this by insmod/modprobe
+setting the lldd_max_execute_num to something greater than
+1.
+
+(2) SAS 1.1 does not define I_T Nexus Reset TMF.
+
+Events
+------
+
+Events are _the only way_ a SAS LLDD notifies the SAS layer
+of anything.  There is no other method or way a LLDD to tell
+the SAS layer of anything happening internally or in the SAS
+domain.
+
+Phy events:
+	PHYE_LOSS_OF_SIGNAL, (C)
+	PHYE_OOB_DONE,
+	PHYE_OOB_ERROR,      (C)
+	PHYE_SPINUP_HOLD.
+
+Port events, passed on a _phy_:
+	PORTE_BYTES_DMAED,      (M)
+	PORTE_BROADCAST_RCVD,   (E)
+	PORTE_LINK_RESET_ERR,   (C)
+	PORTE_TIMER_EVENT,      (C)
+	PORTE_HARD_RESET.
+
+Host Adapter event:
+	HAE_RESET
+
+A SAS LLDD should be able to generate
+	- at least one event from group C (choice),
+	- events marked M (mandatory) are mandatory (only one),
+	- events marked E (expander) if it wants the SAS layer
+	  to handle domain revalidation (only one such).
+	- Unmarked events are optional.
+
+Meaning:
+
+HAE_RESET -- when your HA got internal error and was reset.
+
+PORTE_BYTES_DMAED -- on receiving an IDENTIFY/FIS frame
+PORTE_BROADCAST_RCVD -- on receiving a primitive
+PORTE_LINK_RESET_ERR -- timer expired, loss of signal, loss
+of DWS, etc. (*)
+PORTE_TIMER_EVENT -- DWS reset timeout timer expired (*)
+PORTE_HARD_RESET -- Hard Reset primitive received.
+
+PHYE_LOSS_OF_SIGNAL -- the device is gone (*)
+PHYE_OOB_DONE -- OOB went fine and oob_mode is valid
+PHYE_OOB_ERROR -- Error while doing OOB, the device probably
+got disconnected. (*)
+PHYE_SPINUP_HOLD -- SATA is present, COMWAKE not sent.
+
+(*) should set/clear the appropriate fields in the phy,
+    or alternatively call the inlined sas_phy_disconnected()
+    which is just a helper, from their tasklet.
+
+The Execute Command SCSI RPC:
+
+	int (*lldd_execute_task)(struct sas_task *, int num,
+				 unsigned long gfp_flags);
+
+Used to queue a task to the SAS LLDD.  @task is the tasks to
+be executed.  @num should be the number of tasks being
+queued at this function call (they are linked listed via
+task::list), @gfp_mask should be the gfp_mask defining the
+context of the caller.
+
+This function should implement the Execute Command SCSI RPC,
+or if you're sending a SCSI Task as linked commands, you
+should also use this function.
+
+That is, when lldd_execute_task() is called, the command(s)
+go out on the transport *immediately*.  There is *no*
+queuing of any sort and at any level in a SAS LLDD.
+
+The use of task::list is two-fold, one for linked commands,
+the other discussed below.
+
+It is possible to queue up more than one task at a time, by
+initializing the list element of struct sas_task, and
+passing the number of tasks enlisted in this manner in num.
+
+Returns: -SAS_QUEUE_FULL, -ENOMEM, nothing was queued;
+	 0, the task(s) were queued.
+
+If you want to pass num > 1, then either
+A) you're the only caller of this function and keep track
+   of what you've queued to the LLDD, or
+B) you know what you're doing and have a strategy of
+   retrying.
+
+As opposed to queuing one task at a time (function call),
+batch queuing of tasks, by having num > 1, greatly
+simplifies LLDD code, sequencer code, and _hardware design_,
+and has some performance advantages in certain situations
+(DBMS).
+
+The LLDD advertises if it can take more than one command at
+a time at lldd_execute_task(), by setting the
+lldd_max_execute_num parameter (controlled by "collector"
+module parameter in aic94xx SAS LLDD).
+
+You should leave this to the default 1, unless you know what
+you're doing.
+
+This is a function of the LLDD, to which the SAS layer can
+cater to.
+
+int lldd_queue_size
+	The host adapter's queue size.  This is the maximum
+number of commands the lldd can have pending to domain
+devices on behalf of all upper layers submitting through
+lldd_execute_task().
+
+You really want to set this to something (much) larger than
+1.
+
+This _really_ has absolutely nothing to do with queuing.
+There is no queuing in SAS LLDDs.
+
+struct sas_task {
+	dev -- the device this task is destined to
+	list -- must be initialized (INIT_LIST_HEAD)
+	task_proto -- _one_ of enum sas_proto
+	scatter -- pointer to scatter gather list array
+	num_scatter -- number of elements in scatter
+	total_xfer_len -- total number of bytes expected to be transfered
+	data_dir -- PCI_DMA_...
+	task_done -- callback when the task has finished execution
+};
+
+When an external entity, entity other than the LLDD or the
+SAS Layer, wants to work with a struct domain_device, it
+_must_ call kobject_get() when getting a handle on the
+device and kobject_put() when it is done with the device.
+
+This does two things:
+     A) implements proper kfree() for the device;
+     B) increments/decrements the kref for all players:
+     domain_device
+	all domain_device's ... (if past an expander)
+	    port
+		host adapter
+		     pci device
+			 and up the ladder, etc.
+
+DISCOVERY
+---------
+
+The sysfs tree has the following purposes:
+    a) It shows you the physical layout of the SAS domain at
+       the current time, i.e. how the domain looks in the
+       physical world right now.
+    b) Shows some device parameters _at_discovery_time_.
+
+This is a link to the tree(1) program, very useful in
+viewing the SAS domain:
+ftp://mama.indstate.edu/linux/tree/
+I expect user space applications to actually create a
+graphical interface of this.
+
+That is, the sysfs domain tree doesn't show or keep state if
+you e.g., change the meaning of the READY LED MEANING
+setting, but it does show you the current connection status
+of the domain device.
+
+Keeping internal device state changes is responsibility of
+upper layers (Command set drivers) and user space.
+
+When a device or devices are unplugged from the domain, this
+is reflected in the sysfs tree immediately, and the device(s)
+removed from the system.
+
+The structure domain_device describes any device in the SAS
+domain.  It is completely managed by the SAS layer.  A task
+points to a domain device, this is how the SAS LLDD knows
+where to send the task(s) to.  A SAS LLDD only reads the
+contents of the domain_device structure, but it never creates
+or destroys one.
+
+Expander management from User Space
+-----------------------------------
+
+In each expander directory in sysfs, there is a file called
+"smp_portal".  It is a binary sysfs attribute file, which
+implements an SMP portal (Note: this is *NOT* an SMP port),
+to which user space applications can send SMP requests and
+receive SMP responses.
+
+Functionality is deceptively simple:
+
+1. Build the SMP frame you want to send. The format and layout
+   is described in the SAS spec.  Leave the CRC field equal 0.
+open(2)
+2. Open the expander's SMP portal sysfs file in RW mode.
+write(2)
+3. Write the frame you built in 1.
+read(2)
+4. Read the amount of data you expect to receive for the frame you built.
+   If you receive different amount of data you expected to receive,
+   then there was some kind of error.
+close(2)
+All this process is shown in detail in the function do_smp_func()
+and its callers, in the file "expander_conf.c".
+
+The kernel functionality is implemented in the file
+"sas_expander.c".
+
+The program "expander_conf.c" implements this. It takes one
+argument, the sysfs file name of the SMP portal to the
+expander, and gives expander information, including routing
+tables.
+
+The SMP portal gives you complete control of the expander,
+so please be careful.