scsi: NCR5380: Add SCp members to struct NCR5380_cmd

This is necessary for the eventual removal of SCp from struct scsi_cmnd.

Link: https://lore.kernel.org/r/20220218195117.25689-9-bvanassche@acm.o

scsi: NCR5380: Add SCp members to struct NCR5380_cmd

This is necessary for the eventual removal of SCp from struct scsi_cmnd.

Link: https://lore.kernel.org/r/20220218195117.25689-9-bvanassche@acm.org
Cc: Michael Schmitz <schmitzmic@gmail.com>
Cc: Ondrej Zary <linux@zary.sk>
Suggested-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

show more ...

scsi: NCR5380: Remove the NCR5380_CMD_SIZE macro

This makes it easier to find users of the NCR5380_cmd data structure with
'grep'.

Link: https://lore.kernel.org/r/20220218195117.25689-8-bvanassche@

scsi: NCR5380: Remove the NCR5380_CMD_SIZE macro

This makes it easier to find users of the NCR5380_cmd data structure with
'grep'.

Link: https://lore.kernel.org/r/20220218195117.25689-8-bvanassche@acm.org
Cc: Finn Thain <fthain@telegraphics.com.au>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ondrej Zary <linux@rainbow-software.org>
Cc: Michael Schmitz <schmitzmic@gmail.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

show more ...

scsi: NCR5380: Remove context check

NCR5380_poll_politely2() uses in_interrupt() and irqs_disabled() to check
if it is safe to sleep.

Such usage in drivers is phased out and Linus clearly requested

scsi: NCR5380: Remove context check

NCR5380_poll_politely2() uses in_interrupt() and irqs_disabled() to check
if it is safe to sleep.

Such usage in drivers is phased out and Linus clearly requested that code
which changes behaviour depending on context should either be separated, or
the context be explicitly conveyed in an argument passed by the caller.

Below is a context analysis of NCR5380_poll_politely2() uppermost callers:

- NCR5380_maybe_reset_bus(), task, invoked during device probe.
-> NCR5380_poll_politely()
-> do_abort()

- NCR5380_select(), task, but can only sleep in the "release, then
re-acquire" regions of the spinlock held by its caller.
Sleeping invocations (lock released):
-> NCR5380_poll_politely2()

Atomic invocations (lock acquired):
-> NCR5380_reselect()
-> NCR5380_poll_politely()
-> do_abort()
-> NCR5380_transfer_pio()

- NCR5380_intr(), interrupt handler
-> NCR5380_dma_complete()
-> NCR5380_transfer_pio()
-> NCR5380_poll_politely()
-> NCR5380_reselect() (see above)

- NCR5380_information_transfer(), task, but can only sleep in the
"release, then re-acquire" regions of the caller-held spinlock.
Sleeping invocations (lock released):
- NCR5380_transfer_pio() -> NCR5380_poll_politely()
- NCR5380_poll_politely()

Atomic invocations (lock acquired):
- NCR5380_transfer_dma()
-> NCR5380_dma_recv_setup()
=> generic_NCR5380_precv() -> NCR5380_poll_politely()
=> macscsi_pread() -> NCR5380_poll_politely()

-> NCR5380_dma_send_setup()
=> generic_NCR5380_psend -> NCR5380_poll_politely2()
=> macscsi_pwrite() -> NCR5380_poll_politely()

-> NCR5380_poll_politely2()
-> NCR5380_dma_complete()
-> NCR5380_transfer_pio()
-> NCR5380_poll_politely()
- NCR5380_transfer_pio() -> NCR5380_poll_politely

- NCR5380_reselect(), atomic, always called with hostdata spinlock
held.

Since NCR5380_poll_politely2() already takes a "wait" argument in jiffies,
use it to determine if the function can sleep. Modify atomic callers, which
passed an unused wait value in terms of HZ, to pass zero.

Link: https://lore.kernel.org/r/20201206075157.19067-1-a.darwish@linutronix.de
Cc: Michael Schmitz <schmitzmic@gmail.com>
Cc: <linux-m68k@lists.linux-m68k.org>
Suggested-by: Finn Thain <fthain@telegraphics.com.au>
Co-developed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

show more ...

Revert "scsi: ncr5380: Increase register polling limit"

This reverts commit 4822827a69d7cd3bc5a07b7637484ebd2cf88db6.

The purpose of that commit was to suppress a timeout warning message which
appe

Revert "scsi: ncr5380: Increase register polling limit"

This reverts commit 4822827a69d7cd3bc5a07b7637484ebd2cf88db6.

The purpose of that commit was to suppress a timeout warning message which
appeared to be caused by target latency. But suppressing the warning is
undesirable as the warning may indicate a messed up transfer count.

Another problem with that commit is that 15 ms is too long to keep
interrupts disabled as interrupt latency can cause system clock drift and
other problems.

Cc: Michael Schmitz <schmitzmic@gmail.com>
Cc: stable@vger.kernel.org
Fixes: 4822827a69d7 ("scsi: ncr5380: Increase register polling limit")
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Stan Johnson <userm57@yahoo.com>
Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

show more ...

scsi: NCR5380: Have NCR5380_select() return a bool

The return value is taken to mean "retry" or "don't retry". Change it to bool
to improve readability. Fix related comments. No functional change.

scsi: NCR5380: Have NCR5380_select() return a bool

The return value is taken to mean "retry" or "don't retry". Change it to bool
to improve readability. Fix related comments. No functional change.

Tested-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

show more ...

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

scsi: ncr5380: Clean up dead code and redundant macro usage

Remove dead code inside #if 0 conditionals.

Remove the #ifdef __KERNEL__ test, since NCR5380.h has no definitions
that relate to userspac

scsi: ncr5380: Clean up dead code and redundant macro usage

Remove dead code inside #if 0 conditionals.

Remove the #ifdef __KERNEL__ test, since NCR5380.h has no definitions
that relate to userspace code.

Remove two redundant macro definitions which were overlooked in
commit e9db3198e08b ("sun3_scsi: Adopt NCR5380.c core driver").

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
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>

show more ...

scsi: ncr5380: Shorten host info string by removing unused option macros

The DIFFERENTIAL and PARITY option macros are unused: no supported
hardware uses differential signalling and the core driver

scsi: ncr5380: Shorten host info string by removing unused option macros

The DIFFERENTIAL and PARITY option macros are unused: no supported
hardware uses differential signalling and the core driver never
implemented parity checking. These options just waste space in the host
info string.

While we are here, fix a typo in the NCR5380_info() kernel-doc comment.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
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>

show more ...

scsi: g_NCR5380: Use probe_irq_*() for IRQ probing

Use standard probe_irq_on() and probe_irq_off() functions instead of own
implementation. This prevents warning messages like this in the kernel
lo

scsi: g_NCR5380: Use probe_irq_*() for IRQ probing

Use standard probe_irq_on() and probe_irq_off() functions instead of own
implementation. This prevents warning messages like this in the kernel
log: genirq: Flags mismatch irq 1. 00000000 (NCR-probe) vs. 00000080
(i8042)

Move the IRQ trigger code from NCR5380 to g_NCR5380 where it is used.

Also clear interrupt flag before and after the probe.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

show more ...

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 alt

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>

show more ...

scsi: ncr5380: Expedite register polling

Avoid the call to NCR5380_poll_politely2() when possible. The call is
easily short-circuited on the PIO fast path, using the inline wrapper.
This requires th

scsi: ncr5380: Expedite register polling

Avoid the call to NCR5380_poll_politely2() when possible. The call is
easily short-circuited on the PIO fast path, using the inline wrapper.
This requires that the NCR5380_read macro be made available before
any #include "NCR5380.h" so a few declarations have to be moved too.

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>

show more ...

scsi: ncr5380: Pass hostdata pointer to register polling routines

Pass a NCR5380_hostdata struct pointer to the board-specific routines
instead of a Scsi_Host struct pointer. This reduces pointer ch

scsi: ncr5380: Pass hostdata pointer to register polling routines

Pass a NCR5380_hostdata struct pointer to the board-specific routines
instead of a Scsi_Host struct pointer. This reduces pointer chasing in
the PIO and PDMA fast paths. The old way was a mistake because it is
slow and the board-specific code is not concerned with the mid-layer.

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>

show more ...

scsi: ncr5380: Use correct types for device register accessors

For timeout values adopt unsigned long, which is the type of jiffies etc.

For chip register values and bit masks pass u8, which is the

scsi: ncr5380: Use correct types for device register accessors

For timeout values adopt unsigned long, which is the type of jiffies etc.

For chip register values and bit masks pass u8, which is the return type
of readb, inb etc.

For device register offsets adopt unsigned int, as it is suitable for
adding to base addresses.

Pass the NCR5380_hostdata pointer to the board-specific routines instead
of the Scsi_Host pointer. The board-specific code is concerned with
hardware and not with SCSI protocol or the mid-layer.

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>

show more ...

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,
boar

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>

show more ...

scsi: ncr5380: Improve hostdata struct member alignment and cache-ability

Re-order struct members so that hot data lies at the beginning of the
struct and cold data at the end. Improve the comments

scsi: ncr5380: Improve hostdata struct member alignment and cache-ability

Re-order struct members so that hot data lies at the beginning of the
struct and cold data at the end. Improve the comments while we're here.

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>

show more ...

scsi: ncr5380: Increase register polling limit

If NCR5380_poll_politely() is called under irq lock, the polling time
limit is clamped to avoid a spike in interrupt latency. When not under
irq lock,

scsi: ncr5380: Increase register polling limit

If NCR5380_poll_politely() is called under irq lock, the polling time
limit is clamped to avoid a spike in interrupt latency. When not under
irq lock, the same polling time limit acts as the worst case delay
between schedule() calls.

During PDMA (under irq lock) I've found that the 10 ms time limit is
sometimes too short, and leads to the error message,
sd 0:0:0:0: [sda] tag#1 macscsi_pread: !REQ and !ACK

This particular target identifies itself as a QUANTUM DAYTONA514S. It
seems to be slower to assert ACK than the other targets I've tested.
This patch solves the problem by increasing the polling timeout.

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>

show more ...

scsi: ncr5380: Simplify register polling limit

When polling a device register under irq lock the polling loop terminates
after a given number of jiffies. Make this timeout independent of the HZ
sett

scsi: ncr5380: Simplify register polling limit

When polling a device register under irq lock the polling loop terminates
after a given number of jiffies. Make this timeout independent of the HZ
setting.

All 5380 drivers benefit from this patch, which optimizes the PIO fast
path, because they all use PIO transfers (for phases other than DATA IN
and DATA OUT). Some cards support only PIO transfers (even for DATA
phases). CPU cycles are scarce on some of these systems, so a small
improvement here makes a big difference.

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>

show more ...

scsi: ncr5380: Improve interrupt latency during PIO tranfers

Large PIO transfers are broken up into chunks to try to avoid disabling
local IRQs for long periods. But IRQs are still disabled for too

scsi: ncr5380: Improve interrupt latency during PIO tranfers

Large PIO transfers are broken up into chunks to try to avoid disabling
local IRQs for long periods. But IRQs are still disabled for too long
and this causes SCC FIFO overruns during serial port transfers.

This patch reduces the PIO chunk size to reduce interrupt latency to
something on the order of milliseconds, at the expense of additional CPU
overhead from extra iterations of the NCR5380_main() loop.

That CPU overhead is a problem for slow machines (e.g. mac_scsi on 25
MHz 68030) but these machines generally use PDMA not PIO. This patch
doesn't make the overhead any worse on my Mac LC III (because it only
gets about 510 accesses per ms).

This patch decreases disk performance by a fraction of one percent for
dmx3191d on my 333 MHz PowerPC 750. Other affected hardware (such as
g_NCR5380 on x86) was not tested but 5380 ISA cards generally use PDMA
and not PIO.

[mkp: fix whitespace]

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Reviewed-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

show more ...

scsi: ncr5380: Avoid a compiler warning

With commit 3a0f64bfa907 ("mac_scsi: Fix pseudo DMA implementation")
some versions of gcc now warn:

In file included from drivers/scsi/mac_scsi.c:335:
driver

scsi: ncr5380: Avoid a compiler warning

With commit 3a0f64bfa907 ("mac_scsi: Fix pseudo DMA implementation")
some versions of gcc now warn:

In file included from drivers/scsi/mac_scsi.c:335:
drivers/scsi/NCR5380.h:295: warning: `NCR5380_poll_politely' declared inline after being called
drivers/scsi/NCR5380.h:295: warning: previous declaration of `NCR5380_poll_politely' was here

Avoid this by defining NCR5380_poll_politely() in NCR5380.h.

[mkp: checkpatch warnings]

Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

show more ...

mac_scsi: Fix pseudo DMA implementation

Fix various issues: Comments about bus errors are incorrect. The
PDMA asm must return the size of the memory access that faulted so the
transfer count can be

mac_scsi: Fix pseudo DMA implementation

Fix various issues: Comments about bus errors are incorrect. The
PDMA asm must return the size of the memory access that faulted so the
transfer count can be adjusted accordingly. A phase change may cause a
bus error but should not be treated as failure. A bus error does not
always imply a phase change and generally the transfer may continue.
Scatter/gather doesn't seem to work with PDMA due to overruns. This is
a pity because peak throughput seems to double with SG_ALL.
Tested on a Mac LC III and a PowerBook 520.

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>

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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@gmai

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>

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ncr5380: Remove disused atari_NCR5380.c core driver

Now that atari_scsi and sun3_scsi have been converted to use the NCR5380.c
core driver, remove atari_NCR5380.c. Also remove the last vestiges of i

ncr5380: Remove disused atari_NCR5380.c core driver

Now that atari_scsi and sun3_scsi have been converted to use the NCR5380.c
core driver, remove atari_NCR5380.c. Also remove the last vestiges of its
Tagged Command Queueing implementation from the wrapper drivers.

The TCQ support in atari_NCR5380.c is abandoned by this patch. It is not
merged into the remaining core driver because,

1) atari_scsi defines SUPPORT_TAGS but leaves FLAG_TAGGED_QUEUING disabled
by default, which indicates that it is mostly undesirable.

2) I'm told that it doesn't work correctly when enabled.

3) The algorithm does not make use of block layer tags which it will have
to do because scmd->tag is deprecated.

4) sun3_scsi doesn't define SUPPORT_TAGS at all, yet the the SUPPORT_TAGS
macro interacts with the CONFIG_SUN3 macro in 'interesting' ways.

5) Compile-time configuration with macros like SUPPORT_TAGS caused the
configuration space to explode, leading to untestable and unmaintainable
code that is too hard to reason about.

The merge_contiguous_buffers() code is also abandoned. This was unused
by sun3_scsi. Only atari_scsi used it and then only on TT, because only TT
supports scatter/gather. I suspect that the TT would work fine with
ENABLE_CLUSTERING instead. If someone can benchmark the difference then
perhaps the merge_contiguous_buffers() code can be be justified. Until
then we are better off without the extra complexity.

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>

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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

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>

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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.

Unfortunatel

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>

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ncr5380: Remove REAL_DMA and REAL_DMA_POLL macros

For the NCR5380.c core driver, these macros are never used.
If REAL_DMA were to be defined, compilation would fail.

For the atari_NCR5380.c core dr

ncr5380: Remove REAL_DMA and REAL_DMA_POLL macros

For the NCR5380.c core driver, these macros are never used.
If REAL_DMA were to be defined, compilation would fail.

For the atari_NCR5380.c core driver, REAL_DMA is always defined.

Hence these macros are pointless.

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>

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