Commit Graph

71 Commits

Author SHA1 Message Date
Ondrej Zary
7b93ca43b7 scsi: g_NCR5380: Fix release_region in error handling
When a SW-configurable card is specified but not found, the driver
releases wrong region, causing the following message in kernel log:
Trying to free nonexistent resource <0000000000000000-000000000000000f>

Fix it by assigning base earlier.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Fixes: a8cfbcaec0 ("scsi: g_NCR5380: Stop using scsi_module.c")
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-12 10:42:44 -05:00
Finn Thain
4a98f896bf scsi: ncr5380: Use correct types for DMA routines
Apply prototypes to get consistent function signatures for the DMA
functions implemented in the board-specific drivers. To avoid using
macros to alter actual parameters, some of those functions are reworked
slightly.

This is a step toward the goal of passing the board-specific routines
to the core driver using an ops struct (as in a platform driver or
library module).

This also helps fix some inconsistent types: where the core driver uses
ints (cmd->SCp.this_residual and hostdata->dma_len) for keeping track of
transfers, certain board-specific routines used unsigned long.

While we are fixing these function signatures, pass the hostdata pointer
to DMA routines instead of a Scsi_Host pointer, for shorter and faster
code.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-08 17:29:48 -05:00
Finn Thain
820682b1b3 scsi: ncr5380: Store IO ports and addresses in host private data
The various 5380 drivers inconsistently store register pointers
either in the Scsi_Host struct "legacy crap" area or in special,
board-specific members of the NCR5380_hostdata struct. Uniform
use of the latter struct makes for simpler and faster code (see
the following patches) and helps to reduce use of the
NCR5380_implementation_fields macro.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-08 17:29:48 -05:00
Ondrej Zary
b61bacbc2b scsi: g_NCR5380: Merge g_NCR5380 and g_NCR5380_mmio drivers
Merge the port-mapped IO and memory-mapped IO support (with the help of
ioport_map) into the g_NCR5380 module and delete g_NCR5380_mmio.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-08 17:29:47 -05:00
Ondrej Zary
a8cfbcaec0 scsi: g_NCR5380: Stop using scsi_module.c
Convert g_NCR5380 to use scsi_add_host instead of scsi_module.c Use
pnp_driver and isa_driver to manage cards.

In order to support multiple cards, new module parameter format is
introduced. The old parameters are kept for compatibility.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Acked-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-09-29 21:52:43 -04:00
Ondrej Zary
d91f5afe59 scsi: g_NCR5380: Reduce overrides[] from array to struct
Remove compile-time card type definition GENERIC_NCR5380_OVERRIDE.  Then
remove all code iterating the overrides[] array and reduce it to struct
card.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Acked-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-09-29 21:52:10 -04:00
Ondrej Zary
c47946c2dd scsi: g_NCR5380: Remove deprecated __setup
Remove deprecated __setup for parsing command line parameters.
g_NCR5380.* parameters could be used instead.

This might break existing setups with g_NCR5380 built-in (if there are
any). But it has to go in order to remove the overrides[] array.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Acked-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-09-29 21:50:36 -04:00
Finn Thain
9c41ab27e3 ncr5380: Update usage documentation
Update kernel parameter documentation for atari_scsi, mac_scsi and
g_NCR5380 drivers. Remove duplication.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11 16:57:09 -04:00
Finn Thain
a46865dcf1 ncr5380: Remove DONT_USE_INTR and AUTOPROBE_IRQ macros
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11 16:57:09 -04:00
Finn Thain
8053b0ee79 ncr5380: Merge DMA implementation from atari_NCR5380 core driver
Adopt the DMA implementation from atari_NCR5380.c. This means that
atari_scsi and sun3_scsi can make use of the NCR5380.c core driver
and the atari_NCR5380.c driver fork can be made redundant.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11 16:57:09 -04:00
Finn Thain
6c4b88ca59 ncr5380: Use DMA hooks for PDMA
Those wrapper drivers which use DMA define the REAL_DMA macro and
those which use pseudo DMA define PSEUDO_DMA. These macros need to be
removed for a number of reasons, not least of which is to have drivers
share more code.

Redefine the PDMA send and receive hooks as DMA setup hooks, so that the
DMA code can be shared by all 5380 wrapper drivers. This will help to
reunify the forked core driver.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11 16:57:09 -04:00
Finn Thain
f825e40b23 ncr5380: Remove PSEUDO_DMA macro
For those wrapper drivers which only implement Programmed IO, have
NCR5380_dma_xfer_len() evaluate to zero. That allows PDMA to be easily
disabled at run-time and so the PSEUDO_DMA macro is no longer needed.

Also remove the spin counters used for debugging pseudo DMA drivers.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11 16:57:09 -04:00
Finn Thain
1bb4600245 ncr5380: Disable the DMA errata workaround flag by default
The only chip that needs the workarounds enabled is an early NMOS
device. That means that the common case is to disable them.

Unfortunately the sense of the flag is such that it has to be set
for the common case.

Rename the flag so that zero can be used to mean "no errata workarounds
needed". This simplifies the code.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11 16:57:09 -04:00
Finn Thain
7e9ec8d9cc ncr5380: Remove FLAG_NO_PSEUDO_DMA where possible
Drivers that define PSEUDO_DMA also define NCR5380_dma_xfer_len.
The core driver must call NCR5380_dma_xfer_len which means
FLAG_NO_PSEUDO_DMA can be eradicated from the core driver.

dmx3191d doesn't define PSEUDO_DMA and has no use for FLAG_NO_PSEUDO_DMA,
so remove it there also.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11 16:57:09 -04:00
Finn Thain
9d376402c8 g_ncr5380: Remove CONFIG_SCSI_GENERIC_NCR53C400
This change brings a number of improvements: fewer macros, better test
coverage, simpler code and sane Kconfig options. The downside is a small
chance of incompatibility (which seems unavoidable).

CONFIG_SCSI_GENERIC_NCR53C400 exists to enable or inhibit pseudo DMA
transfers when the driver is used with 53C400-compatible cards. Thanks to
Ondrej Zary's patches, PDMA now works which means it can be enabled
unconditionally.

Due to bad design, CONFIG_SCSI_GENERIC_NCR53C400 ties together unrelated
functionality as it sets both PSEUDO_DMA and BIOSPARAM macros. This patch
effectively enables PSEUDO_DMA and disables BIOSPARAM.

The defconfigs and the Kconfig default leave CONFIG_SCSI_GENERIC_NCR53C400
undefined. Red Hat 9 and CentOS 2.1 were the same. This leaves both
PSEUDO_DMA and BIOSPARAM disabled. The effect of this patch should be
better performance from enabling PSEUDO_DMA.

On the other hand, Debian 4 and SLES 10 had CONFIG_SCSI_GENERIC_NCR53C400
enabled, so both PSEUDO_DMA and BIOSPARAM were enabled. This patch might
affect configurations like this by disabling BIOSPARAM. My best guess is
that this could be a problem only in the vanishingly rare case that
1) the CHS values stored in the boot device partition table are wrong and
2) a 5380 card is in use (because PDMA on 53C400 used to be broken).

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11 16:57:09 -04:00
Ondrej Zary
c6084cbce4 ncr5380: Add support for HP C2502
HP C2502 cards (based on 53C400A chips) use different magic numbers for
software-based I/O address configuration than other cards.
The configuration is also extended to allow setting the IRQ.

Move the configuration to a new function magic_configure() and move
magic the magic numbers into an array. Add new magic numbers for these
HP cards and hp_c2502 module parameter to use them, e.g.:
modprobe g_NCR5380 ncr_irq=7 ncr_addr=0x280 hp_c2502=1

Tested with HP C2502 and DTCT-436P.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:43:13 -05:00
Ondrej Zary
42fc6370c9 ncr5380: Fix wait for 53C80 registers registers after PDMA
The check for 53C80 registers accessibility was commented out because
it was broken (inverted). Fix and enable it.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:43:13 -05:00
Ondrej Zary
aeb51152bb ncr5380: Enable PDMA for DTC chips
Add I/O register mapping for DTC chips and enable PDMA mode.

These chips have 16-bit wide HOST BUFFER register and it must be read
by 16-bit accesses (we lose data otherwise).

Large PIO transfers crash at least the DTCT-436P chip (all reads result
in 0xFF) so this patch actually makes it work.

The chip also crashes when we bang on the C400 host status register too
heavily after PDMA write - a small udelay is needed.

Tested on DTCT-436P and verified that it does not break 53C400A.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:43:12 -05:00
Ondrej Zary
cecf3beef0 ncr5380: Enable PDMA for NCR53C400A
Add I/O register mapping for NCR53C400A and enable PDMA mode to
improve performance and fix non-working IRQ.

Tested with HP C2502 (and user-space enabler).

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:43:11 -05:00
Ondrej Zary
12150797d0 ncr5380: Use runtime register mapping
Convert compile-time C400_ register mapping to runtime mapping.
This removes the weird negative register offsets and allows adding
additional mappings.

While at it, convert read/write loops into insb/outsb.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:43:10 -05:00
Ondrej Zary
f03946210d ncr5380: Fix pseudo DMA transfers on 53C400
Pseudo-DMA (PDMA) has been broken for ages, resulting in hangs on
53C400-based cards.

According to 53C400 datasheet, PDMA transfer length must be a multiple
of 128. Check if that's true and use PIO if it's not.

This makes PDMA work on 53C400 (Canon FG2-5202).

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:43:10 -05:00
Finn Thain
0a4e361254 ncr5380: Fix soft lockups
Because of the rudimentary design of the chip, it is necessary to poll the
SCSI bus signals during PIO and this tends to hog the CPU. The driver will
accept new commands while others execute, and this causes a soft lockup
because the workqueue item will not terminate until the issue queue is
emptied.

When exercising dmx3191d using sequential IO from dd, the driver is sent
512 KiB WRITE commands and 128 KiB READs. For a PIO transfer, the rate is
is only about 300 KiB/s, so these are long-running commands. And although
PDMA may run at several MiB/s, interrupts are disabled for the duration
of the transfer.

Fix the unresponsiveness and soft lockup issues by calling cond_resched()
after each command is completed and by limiting max_sectors for drivers
that don't implement real DMA.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:43:09 -05:00
Finn Thain
32b26a1042 ncr5380: Use standard list data structure
The NCR5380 drivers have a home-spun linked list implementation for
scsi_cmnd structs that uses cmd->host_scribble as a 'next' pointer. Adopt
the standard list_head data structure and list operations instead. Remove
the eh_abort_handler rather than convert it. Doing the conversion would
only be churn because the existing EH handlers don't work and get replaced
in a subsequent patch.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:43:07 -05:00
Finn Thain
e5c3fddfaa ncr5380: Remove command list debug code
Some NCR5380 hosts offer a .show_info method to access the contents of
the various command list data structures from a procfs file. When NDEBUG
is set, the same information is sent to the console during EH.

The two core drivers, atari_NCR5380.c and NCR5380.c differ here. Because
it is just for debugging, the easiest way to fix the discrepancy is
simply remove this code.

The only remaining users of NCR5380_show_info() and NCR5380_write_info()
are drivers that define PSEUDO_DMA. The others have no use for the
.show_info method, so don't initialize it.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:43:05 -05:00
Finn Thain
be3f4121aa ncr5380: Remove redundant ICR_ARBITRATION_LOST test and eliminate FLAG_DTC3181E
Remove FLAG_DTC3181E. It was used to suppress a final Arbitration Lost
(SEL asserted) test that isn't actually needed. The test was suppressed
because it causes problems for DTC436 and DTC536 chips. It takes place
after the host wins arbitration, so SEL has been asserted. These chips
can't seem to tell whether it was the host or another bus device that
did so.

This questionable final test appears in a flow chart in an early NCR5380
datasheet. It was removed from later documents like the DP5380 datasheet.

By the time this final test takes place, the driver has already tested
the Arbitration Lost bit several times. The first test happens 3 us after
BUS FREE (or longer due to register access delays). The protocol requires
that a device stop signalling within 1.8 us after BUS FREE unless it won
arbitration, in which case it must assert SEL, which is detected 1.2 us
later by the first Arbitration Lost test.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:43:04 -05:00
Finn Thain
aa2e2cb1dd ncr5380: Fix and cleanup scsi_host_template initializers
Add missing .module initializer. Use distinct .proc_name values for the
g_NCR5380 and g_NCR5380_mmio modules. Remove pointless CAN_QUEUE and
CMD_PER_LUN override macros. Cleanup whitespace and code style.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:43:03 -05:00
Finn Thain
161c0059a2 ncr5380: Cleanup #include directives
Remove unused includes (stat.h, signal.h, proc_fs.h) and move includes
needed by the core drivers into the common header (delay.h etc).

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:43:02 -05:00
Finn Thain
55181be8ce ncr5380: Replace redundant flags with FLAG_NO_DMA_FIXUP
The flags DMA_WORKS_RIGHT, FLAG_NCR53C400 and FLAG_HAS_LAST_BYTE_SENT
all mean the same thing, i.e. the chip is not a 538[01]. (More recent
devices such as the 53C80 have a 'Last Byte Sent' bit in the Target
Command Register as well as other fixes for End-of-DMA errata.)

These flags have no additional meanings since previous cleanup patches
eliminated the NCR53C400 macro, moved g_NCR5380-specific code out of the
core driver and standardized interrupt handling.

Use the FLAG_NO_DMA_FIXUP flag to suppress End-of-DMA errata workarounds,
for those cards and drivers that make use of the TCR_LAST_BYTE_SENT bit.
Remove the old flags.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:43:01 -05:00
Finn Thain
cd400825c9 ncr5380: Standardize interrupt handling
Because interrupt handling is crucial to the core driver(s), all wrapper
drivers need to agree on this code. This patch removes discrepancies.

NCR5380_intr() in NCR5380.c has the following pointless loop that differs
from the code in atari_NCR5380.c.

	done = 1;
	do {
		/* ... */
	} while (!done);

The 'done' flag gets cleared when a reconnected command is to be processed
from the work queue. But in NCR5380.c, the flag is also used to cause the
interrupt conditions to be re-examined. Perhaps this was because
NCR5380_reselect() was expected to cause another interrupt, or perhaps
the remaining present interrupt conditions need to be handled after the
NCR5380_reselect() call?

Actually, both possibilities are bogus, as is the loop itself. It seems
have been overlooked in the hit-and-miss removal of scsi host instance
list iteration many years ago; see history/history.git commit 491447e1fcff
("[PATCH] next NCR5380 updates") and commit 69e1a9482e57 ("[PATCH] fix up
NCR5380 private data"). See also my earlier patch, "Always retry
arbitration and selection".

The datasheet says, "IRQ can be reset simply by reading the Reset
Parity/Interrupt Register". So don't treat the chip IRQ like a
level-triggered interrupt. Of the conditions that set the IRQ flag,
some are level-triggered and some are edge-triggered, which means IRQ
itself must be edge-triggered.

Some interrupt conditions are latched and some are not. Before clearing
the chip IRQ flag, clear all state that may cause it to be raised. That
means clearing the DMA Mode and Busy Monitor bits in the Mode Register
and clearing the host ID in the Select Enable register.

Also clean up some printk's and some comments. Keep atari_NCR5380.c and
NCR5380.c in agreement.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:43:00 -05:00
Finn Thain
686f3990e6 ncr5380: Rework disconnect versus poll logic
The atari_NCR5380.c and NCR5380.c core drivers differ in their handling of
target disconnection. This is partly because atari_NCR5380.c had all of
the polling and sleeping removed to become entirely interrupt-driven, and
it is partly because of damage done to NCR5380.c after atari_NCR5380.c was
forked. See commit 37cd23b44929 ("Linux 2.1.105") in history/history.git.

The polling changes that were made in v2.1.105 are questionable at best:
if REQ is not already asserted when NCR5380_transfer_pio() is invoked, and
if the expected phase is DATA IN or DATA OUT, the function will schedule
main() to execute after USLEEP_SLEEP jiffies and then return. The problems
here are the expected REQ timing and the sleep interval*. Avoid this issue
by using NCR5380_poll_politely() instead of scheduling main().

The atari_NCR5380.c core driver requires the use of the chip interrupt and
always permits target disconnection. It sets the cmd->device->disconnect
flag when a device disconnects, but never tests this flag.

The NCR5380.c core driver permits disconnection only when
instance->irq != NO_IRQ. It sets the cmd->device->disconnect flag when
a device disconnects and it tests this flag in a couple of places:

1. During NCR5380_information_transfer(), following COMMAND OUT phase,
   if !cmd->device->disconnect, the initiator will take a guess as to
   whether or not the target will then choose to go to MESSAGE IN phase
   and disconnect. If the driver guesses "yes", it will schedule main()
   to execute after USLEEP_SLEEP jiffies and then return there.

   Unfortunately the driver may guess "yes" even after it has denied
   the target the disconnection privilege. When the target does not
   disconnect, the sleep can be beneficial, assuming the sleep interval
   is appropriate (mostly it is not*).

   And even if the driver guesses "yes" correctly, and the target would
   then disconnect, the driver still has to go through the MESSAGE IN
   phase in order to get to BUS FREE phase. The main loop can do nothing
   useful until BUS FREE, and sleeping just delays the phase transition.

2. If !cmd->device->disconnect and REQ is not already asserted when
   NCR5380_information_transfer() is invoked, the function polls for REQ
   for USLEEP_POLL jiffies. If REQ is not asserted, it then schedules
   main() to execute after USLEEP_SLEEP jiffies and returns.

   The idea is apparently to yeild the CPU while waiting for REQ.
   This is conditional upon !cmd->device->disconnect, but there seems
   to be no rhyme or reason for that. For example, the flag may be
   unset because disconnection privilege was denied because the driver
   has no IRQ. Or the flag may be unset because the device has never
   needed to disconnect before. Or if the flag is set, disconnection
   may have no relevance to the present bus phase.

Another deficiency of the existing algorithm is as follows. When the
driver has no IRQ, it prevents disconnection, and generally polls and
sleeps more than it would normally. Now, if the driver is going to poll
anyway, why not allow the target to disconnect? That way the driver can do
something useful with the bus instead of polling unproductively!

Avoid this pointless latency, complexity and guesswork by using
NCR5380_poll_politely() instead of scheduling main().

* For g_NCR5380, the time intervals for USLEEP_SLEEP and USLEEP_POLL are
  200 ms and 10 ms, respectively. They are 20 ms and 200 ms respectively
  for the other NCR5380 drivers. There doesn't seem to be any reason for
  this discrepancy. The timing seems to have no relation to the type of
  adapter. Bizarrely, the timing in g_NCR5380 seems to relate only to one
  particular type of target device. This patch attempts to solve the
  problem for all NCR5380 drivers and all target devices.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:42:56 -05:00
Finn Thain
ff3d457884 ncr5380: Implement NCR5380_dma_xfer_len and remove LIMIT_TRANSFERSIZE macro
Follow the example of the atari_NCR5380.c core driver and adopt the
NCR5380_dma_xfer_len() hook. Implement NCR5380_dma_xfer_len() for dtc.c
and g_NCR5380.c to take care of the limitations of these cards. Keep the
default for drivers using PSEUDO_DMA.

Eliminate the unused macro LIMIT_TRANSFERSIZE.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:42:56 -05:00
Finn Thain
0ad0eff98f ncr5380: Introduce unbound workqueue
Allocate a work queue that will permit busy waiting and sleeping. This
means NCR5380_init() can potentially fail, so add this error path.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:42:56 -05:00
Finn Thain
4d029e9ae9 ncr5380: Eliminate USLEEP_WAITLONG delay
Linux 2.1.105 introduced the USLEEP_WAITLONG delay, apparently "needed for
Mustek scanners". It is intended to stall the issue queue for 5 seconds.
There are a number of problems with this.

1. Only g_NCR5380 enables the delay, which implies that the other five
   drivers using the NCR5380.c core driver remain incompatible with
   Mustek scanners.

2. The delay is not implemented by atari_NCR5380.c, which is problematic
   for re-unifying the two core driver forks.

3. The delay is implemented using NCR5380_set_timer() which makes it
   unreliable. A new command queued by the mid-layer cancels the delay.

4. The delay is applied indiscriminately in several situations in which
   NCR5380_select() returns -1. These are-- reselection by the target,
   failure of the target to assert BSY, and failure of the target to
   assert REQ. It's clear from the comments that USLEEP_WAITLONG is not
   relevant to the reselection case. And reportedly, these scanners do
   not disconnect.

5. atari_NCR5380.c was forked before Linux 2.1.105, so it was spared some
   of the damage done to NCR5380.c. In this case, the atari_NCR5380.c core
   driver was more standard-compliant and may not have needed any
   workaround like the USLEEP_WAITLONG kludge. The compliance issue was
   addressed in the previous patch.

If these scanners still don't work, we need a better solution. Retrying
selection until EH aborts a command offers equivalent robustness. Bugs in
the existing driver prevent EH working correctly but this is addressed in
a subsequent patch. Remove USLEEP_WAITLONG.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:42:55 -05:00
Finn Thain
4d8c08c71e ncr5380: Move NCR53C400-specific code
Move board-specific code like this,
	NCR5380_write(C400_CONTROL_STATUS_REG, CSR_BASE);
from the core driver to the board driver. Eliminate the NCR53C400 macro
from the core driver. Removal of all macros like this one will be
necessary in order to have one core driver that can support all kinds of
boards.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:42:52 -05:00
Finn Thain
b6488f97d3 ncr5380: Split NCR5380_init() into two functions
This patch splits the NCR5380_init() function into two parts, similar
to the scheme used with atari_NCR5380.c. This avoids two problems.

Firstly, NCR5380_init() may perform a bus reset, which would cause the
chip to assert IRQ. The chip is unable to mask its bus reset interrupt.
Drivers can't call request_irq() before calling NCR5380_init(), because
initialization must happen before the interrupt handler executes. If
driver initialization causes an interrupt it may be problematic on some
platforms. To avoid that, first move the bus reset code into
NCR5380_maybe_reset_bus().

Secondly, NCR5380_init() contains some board-specific interrupt setup code
for the NCR53C400 that does not belong in the core driver. In moving this
code, better not re-order interrupt initialization and bus reset. Again,
the solution is to move the bus reset code into NCR5380_maybe_reset_bus().

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:42:52 -05:00
Finn Thain
b01ec34895 ncr5380: Remove NCR5380_instance_name macro
This macro makes the code cryptic. Remove it.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:42:52 -05:00
Finn Thain
54d8fe4425 ncr5380: Remove NCR5380_local_declare and NCR5380_setup macros
The NCR5380_local_declare and NCR5380_setup macros exist to define and
initialize a particular local variable, to provide the address of the
chip registers needed for the driver's implementation of its
NCR5380_read/write register access macros.

In cumana_1 and macscsi, these macros generate pointless code like this,
	struct Scsi_Host *_instance;
	_instance = instance;

In pas16, the use of NCR5380_read/write in pas16_hw_detect() requires that
the io_port local variable has been defined and initialized, but the
NCR5380_local_declare and NCR5380_setup macros can't be used for that
purpose because the Scsi_Host struct has not yet been instantiated.

Moreover, these macros were removed from atari_NCR5380.c long ago and
now they constitute yet another discrepancy between the two core driver
forks.

Remove these "optimizations".

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:42:52 -05:00
Finn Thain
c0965e6371 ncr5380: Remove more pointless macros
ASM macro is never defined. rtrc in pas16.c is not used.
NCR5380_map_config, do_NCR5380_intr, do_t128_intr and do_pas16_intr
are unused. NCR_NOT_SET harms readability. Remove them.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:42:51 -05:00
Finn Thain
d5f7e65df0 ncr5380: Remove redundant static variable initializers
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06 21:42:51 -05:00
Nicholas Mc Guire
4e5a800c82 ncr5380: Harmonize jiffies conversion with msecs_to_jiffies
Instances of var * HZ / 1000 are replaced by msecs_to_jiffies(var).
In addition some timing constants that assumed HZ 100 were adjusted
to HZ independent settings based on review comments from Michael Schmitz
<schmitzmic@gmail.com> and review of the original drivers in 1.0.31 and
2.2.16.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Acked-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2015-03-09 10:45:26 -04:00
Geert Uytterhoeven
b026e8ed55 g_NCR5380: Kill compiler warning if builtin
If CONFIG_SCSI_GENERIC_NCR5380=y:

drivers/scsi/g_NCR5380.c:727: warning: 'id_table' defined but not used

In the non-modular case, MODULE_DEVICE_TABLE() expands to nothing, and
id_table is not referenced.

Correct the existing #ifdef to fix this.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2015-03-09 07:42:30 -04:00
Finn Thain
710ddd0d50 ncr5380: Drop legacy scsi.h include
Convert Scsi_Cmnd to struct scsi_cmnd and drop the #include "scsi.h".
The sun3_NCR5380.c core driver already uses struct scsi_cmnd so converting
the other core drivers reduces the diff which makes them easier to unify.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20 09:11:10 +01:00
Finn Thain
96068e6b4d ncr5380: Remove *_RELEASE macros
The *_RELEASE macros don't tell me anything. In some cases the version in
the macro contradicts the version in the comments. Anyway, the Linux kernel
version is sufficient information. Remove these macros to improve readability.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20 09:11:10 +01:00
Finn Thain
8c32513bd3 ncr5380: Cleanup host info() methods
If the host->info() method is not set, then host->name is used by default.
For atari_scsi, that is exactly the same text. So remove the redundant
info() method. Keep sun3_scsi.c in line with atari_scsi.

Some NCR5380 drivers return an empty string from the info() method
(arm/cumana_1.c arm/oak.c mac_scsi.c) while other drivers use the default
(dmx3191d dtc.c g_NCR5380.c pas16.c t128.c).

Implement a common info() method to replace a lot of duplicated code which
the various drivers use to announce the same information.

This replaces most of the (deprecated) show_info() output and all of the
NCR5380_print_info() output. This also eliminates a bunch of code in
g_NCR5380 which just duplicates functionality in the core driver.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20 09:11:08 +01:00
Finn Thain
270ac2c290 ncr5380: Remove NCR5380_STATS
The NCR5380_STATS option is only enabled by g_NCR5380 yet it adds
clutter to all three core drivers. The atari_NCR5380.c and sun3_NCR5380.c
core drivers have a slightly different implementation of the
NCR5380_STATS option.

Out of all ten NCR5380 drivers, only one of them (g_NCR5380) actually
has the code to report on the collected stats. Aside from being unreadable,
that code seems to be broken because there's no initialization of timebase.
sun3_NCR5380.c and atari_NCR5380.c have the timebase initialization but
lack the code to report the stats.

Remove all of this code to improve readability and reduce divergence
between the three core drivers.

This patch and the next one completely eliminate the PRINTP and ANDP
pre-processor abuse.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20 09:11:07 +01:00
Finn Thain
22f5f10d2d ncr5380: Fix SCSI_IRQ_NONE bugs
Oak scsi doesn't use any IRQ, but it sets irq = IRQ_NONE rather than
SCSI_IRQ_NONE. Problem is, the core NCR5380 driver expects SCSI_IRQ_NONE
if it is to issue IDENTIFY commands that prevent target disconnection.
And, as Geert points out, IRQ_NONE is part of enum irqreturn.

Other drivers, when they can't get an IRQ or can't use one, will set
host->irq = SCSI_IRQ_NONE (that is, 255). But when they exit they will
attempt to free IRQ 255 which was never requested.

Fix these bugs by using NO_IRQ in place of SCSI_IRQ_NONE and IRQ_NONE.
That means IRQ 0 is no longer probed by ISA drivers but I don't think
this matters.

Setting IRQ = 255 for these ISA drivers is understood to mean no IRQ.
This remains supported so as to avoid breaking existing ISA setups (which
can be difficult to get working) and because existing documentation
(SANE, TLDP etc) describes this usage for the ISA NCR5380 driver options.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20 09:11:07 +01:00
Finn Thain
3f9e986e2f ncr5380: Remove duplicate comments
The LIMIT_TRANSFERSIZE, PSEUDO_DMA, PARITY and UNSAFE options are all
documented in the core drivers where they are used. The same goes for the
chip databook reference. Remove the duplicate comments.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20 09:11:06 +01:00
Finn Thain
997acab7d5 ncr5380: Remove redundant AUTOSENSE macro
Every NCR5380 driver sets AUTOSENSE so it need not be optional (and the
mid-layer expects it). Remove this redundant macro to improve readability.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20 09:11:06 +01:00
Finn Thain
ed8b9e7f18 ncr5380: Remove useless prototypes
Add missing static qualifiers and remove the now pointless prototypes. The
NCR5380_* prototypes are all declared in NCR5380.h and renamed using macros.
Further declarations are redundant (some are completely unused). Remove
them.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20 09:11:04 +01:00
Finn Thain
48f16c9bef ncr5380: Remove unused macros
Some macros are never evaluated (i.e. FOO, USLEEP, SCSI2 and USE_WRAPPER;
and in some drivers, NCR5380_intr and NCR5380_proc_info). DRIVER_SETUP
serves no purpose anymore. Remove these macro definitions.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20 09:11:04 +01:00