Driver limits SAS external target IDs to range 1-8.
Need to increase limit and clean up overlapping concepts of targets and paths
in the code.

There are several defined constants that control this:
HPSA_MAX_TARGETS_PER_CTLR     16
MAX_MSA2XXX_ENCLOSURES        32
HPSA_MAX_PATHS                8

We can condense this to one constant:
MAX_EXT_TARGETS               32

SAS switches allow for 8 connections, and there is capacity for 4 switches per
enclosure in largest blade enclosure type.
Signed-off-by: NScott Teel <scott.teel@hp.com>
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

[SCSI] hpsa: removed unneeded structure member max_sg_entries and fix badly named constant MAXSGENTRIES

We had both h->max_sg_entries and h->maxsgentries in the per controller
structure which is terribly confusing.  max_sg_entries was really
just a constant, 32, which defines how big the "block fetch table"
is, which is as large as the max number of SG elements embedded
within a command (excluding SG elements in chain blocks).

MAXSGENTRIES was the constant used to denote the max number of SG
elements embedded within a command, also a poor name.

So renamed MAXSGENTREIS to SG_ENTRIES_IN_CMD, and removed
h->max_sg_entries and replaced it with SG_ENTRIES_IN_CMD.

h->maxsgentries is unchanged, and is the maximum number of sg
elements the controller will support in a command, including
those in chain blocks, minus 1 for the chain block pointer..
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

The currentsd[] array in hpsa_update_scsi_devices had room for
256 devices.  The code was iterating over however many physical
and logical devices plus an additional number of possible external
MSA2XXX controllers, which together could potentially exceed 256.

We increased the size of the currentsd array to 1024 + 1024 + 32 + 1
elements to reflect a reasonable maximum possible number of devices
which might be encountered.  We also don't just walk off the end
of the array if the array controller reports more devices than we
are prepared to handle, we just ignore the excessive devices.
Signed-off-by: NScott Teel <scott.teel@hp.com>
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

The bit-2-doorbell reset method seemed to cause (survivable) NMIs
on some systems and (unsurvivable) IOCK NMIs on some G7 servers.
Firmware guys implemented a new doorbell method to alleviate these
problems triggered by bit 5 of the doorbell register.  We want to
use it if it's available.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <jbottomley@parallels.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Detect failure of controller reset by noticing if the 32 bytes of
"driver version" we store on the hardware in the config table
fail to get zeroed out.  Previously we noticed if the controller
did not transition to "simple mode", but this did not detect reset
failure if the controller was already in simple mode prior to
the reset attempt (e.g. due to module parameter hpsa_simple_mode=1).
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <jbottomley@parallels.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <jbottomley@parallels.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Controller will transfer only 32-bits on completion if it
knows we are only using 32-bit tags.  Also, some newer controllers
apparently (and erroneously) require that we only use 32-bit tags,
and that we inform the controller of this.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Driver's internal queues should be FIFO, not LIFO.
This is a port of an almost identical patch from cciss by Jens Axboe.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Some low bits might have been set by the driver, causing
a message like this to come out:

 [   13.288062] ------------[ cut here ]------------
 [   13.293211] WARNING: at lib/dma-debug.c:803 check_unmap+0x1a1/0x654()
 [   13.300387] Hardware name: ProLiant DL180 G6
 [   13.305335] hpsa 0000:06:00.0: DMA-API: device driver tries to free
 DMA memory it has not allocated [device address=0x000000007f81e001]
 [size=640 bytes]
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Smart Array controllers newer than the P600 do not honor the
PCI power state method of resetting the controllers.  Instead,
in these cases we can get them to reset via the "doorbell" register.

This escaped notice until we began using "performant" mode because
the fact that the controllers did not reset did not normally
impede subsequent operation, and so things generally appeared to
"work".  Once the performant mode code was added, if the controller
does not reset, it remains in performant mode.  The code immediately
after the reset presumes the controller is in "simple" mode
(which previously, it had remained in simple mode the whole time).
If the controller remains in performant mode any code which presumes
it is in simple mode will not work.  So the reset needs to be fixed.

Unfortunately there are some controllers which cannot be reset by
either method. (eg. p800).  We detect these cases by noticing that
the controller seems to remain in performant mode even after a
reset has been attempted.  In those case, we proceed anyway,
as if the reset has happened (and skip the step of waiting for
the controller to become ready -- which is expecting it to be in
"simple" mode.)  To sum up, we try to do a better job of resetting
the controller if "reset_devices" is set, and if it doesn't work,
we print a message and try to continue anyway.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

This patch removes unnecessary #define's from hpsa. The SCSI midlayer
handles all this for us.
Signed-off-by: NMike Miller <mike.miller@hp.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

This uses the scatter-gather chaining feature of Smart Array
controllers.  32 scatter-gather elements are embedded in the
"command list", and the last element in the list may be marked
as a "chain pointer", and point to an additional block of
scatter gather elements.  The precise number of scatter gather
elements supported is dependent on the particular kind of
Smart Array, and is determined at runtime by querying the
hardware.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

This is done by adding support for the so-called "performant mode"
(that's really what they called it).  Smart Array controllers
have a mode which enables multiple command completions to be
delivered with a single interrupt, "performant" mode.  We want to use
that mode, as some newer controllers will be requiring this mode.
Signed-off-by: NDon Brace <brace@beardog.cce.hp.com>
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NMike Miller <mikem@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

That is, use u64, u32, u16 and u8 rather than __u64, __u32, __u16 and __u8.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

This driver supports a subset of HP Smart Array Controllers.
It is a SCSI alternative to the cciss driver.

[akpm@linux-foundation.org: avoid helpful cleanup patches]
[achiang@hp.com: make device attrs static]
[akpm@linux-foundation.org: msleep() does set_current_state() itself]
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NMike Miller <mikem@beardog.cce.hp.com>
Signed-off-by: NAlex Chiang <achiang@hp.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>