m68k/mac: Fix race conditions in OSS interrupt dispatch

The interrupt dispatch algorithm used in the OSS driver seems to be
subject to race conditions: an IRQ flag could be lost if asserted between

m68k/mac: Fix race conditions in OSS interrupt dispatch

The interrupt dispatch algorithm used in the OSS driver seems to be
subject to race conditions: an IRQ flag could be lost if asserted between
the MOV instructions from and to the interrupt flag register. But testing
shows that the write to the flag register has no effect, so rewrite the
algorithm without the theoretical race condition.

There is a second theoretical race condition here. When oss_irq() is
called with say, IPL == 2 it will invoke the SCSI interrupt handler.
The SCSI IRQ is then cleared by the mac_scsi driver. If SCSI and NuBus
IRQs are now asserted together, oss_irq() will be invoked with IPL == 3
and the mac_scsi interrupt handler can be re-entered. This re-entrance
issue is not limited to SCSI and could affect NuBus and ADB drivers too.
Fix it by splitting up oss_irq() into separate handlers for each IPL.

No-one seems to know how OSS irq flags can be cleared, if at all, so add
a comment to this effect (actually reinstate one I previously removed).
Testing showed that a slot IRQ with no handler can remain asserted (in
this case a Radius video card) without causing problems for other IRQs.

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

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m68k/mac: Disentangle VIA/RBV and NuBus initialization

The Nubus subsystem should not be concerned with differences between VIA,
RBV and OSS platforms. It should be portable across Macs and PowerMac

m68k/mac: Disentangle VIA/RBV and NuBus initialization

The Nubus subsystem should not be concerned with differences between VIA,
RBV and OSS platforms. It should be portable across Macs and PowerMacs.
This goal has implications for the initialization code relating to bus
locking and slot interrupts.

During Nubus initialization, bus transactions are "unlocked": on VIA2 and
RBV machines, via_nubus_init() sets a bit in the via2[gBufB] register to
allow bus-mastering Nubus cards to arbitrate for the bus. This happens
upon subsys_initcall(nubus_init). But because nubus_init() has no effect
on card state, this sequence is arbitrary.

Moreover, when Penguin is used to boot Linux, the bus is already unlocked
when Linux starts. On OSS machines there's no attempt to unlock Nubus
transactions at all. (Maybe there's no benefit on that platform or maybe
no-one knows how.)

All of this demonstrates that there's no benefit in locking out
bus-mastering cards, as yet. (If the need arises, we could lock the bus
for the duration of a timing-critical operation.) NetBSD unlocks the
Nubus early (at VIA initialization) and we can do the same.

via_nubus_init() is also responsible for some VIA interrupt setup that
should happen earlier than subsys_initcall(nubus_init). And actually, the
Nubus subsystem need not be involved with slot interrupts: SLOT2IRQ
works fine because Nubus slot IRQs are geographically assigned
(regardless of platform).

For certain platforms with PDS slots, some Nubus IRQs may be platform
IRQs and this is not something that the NuBus subsystem should worry
about. So let's invoke via_nubus_init() earlier and make the platform
responsible for bus unlocking and interrupt setup instead of the NuBus
subsystem.

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

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m68k/mac: Disentangle VIA and OSS initialization

macintosh_config->via_type is meaningless on Mac IIfx (i.e. the only
model with OSS chip), so skip the via_type switch statement.

Call oss_init() be

m68k/mac: Disentangle VIA and OSS initialization

macintosh_config->via_type is meaningless on Mac IIfx (i.e. the only
model with OSS chip), so skip the via_type switch statement.

Call oss_init() before via_init() because it is more important and
because that is the right place to initialize the oss_present flag.

On this model, bringing forward oss_init() and delaying via_init()
is no problem because those functions are independent.

The only requirement here is that oss_register_interrupts() happens
after via_init(). That is, mac_init_IRQ() happens after config_mac().

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

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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>

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m68k/mac: Clean up interrupt debug macros and printk statements

Mac interrupt code has been debugged. The Penguin deficiencies that
still cause unhandled interrupts aren't fixable here. Besides,
int

m68k/mac: Clean up interrupt debug macros and printk statements

Mac interrupt code has been debugged. The Penguin deficiencies that
still cause unhandled interrupts aren't fixable here. Besides,
interrupts are fast and frequent and these printk statements
were never really useful IMO. Remove them.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

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genirq: Remove irq argument from irq flow handlers

Most interrupt flow handlers do not use the irq argument. Those few
which use it can retrieve the irq number from the irq descriptor.

Remove the a

genirq: Remove irq argument from irq flow handlers

Most interrupt flow handlers do not use the irq argument. Those few
which use it can retrieve the irq number from the irq descriptor.

Remove the argument.

Search and replace was done with coccinelle and some extra helper
scripts around it. Thanks to Julia for her help!

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jiang Liu <jiang.liu@linux.intel.com>

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m68k/irq: Prepare irq handlers for irq argument removal

The irq argument of most interrupt flow handlers is unused or merily
used instead of a local variable. The handlers which need the irq
argumen

m68k/irq: Prepare irq handlers for irq argument removal

The irq argument of most interrupt flow handlers is unused or merily
used instead of a local variable. The handlers which need the irq
argument can retrieve the irq number from the irq descriptor.

Search and update was done with coccinelle and the invaluable help of
Julia Lawall.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-m68k@lists.linux-m68k.org

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m68k/mac: Fix out-of-bounds array index in OSS IRQ source initialization

Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert

m68k/mac: Fix out-of-bounds array index in OSS IRQ source initialization

Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

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m68k: Remove superfluous inclusions of <asm/bootinfo.h>

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

m68k/mac: oss irq fixes

The IOP driver calls into the OSS driver to enable its IRQ. This undesirable coupling between drivers only exists because the OSS driver doesn't correctly handle all of its m

m68k/mac: oss irq fixes

The IOP driver calls into the OSS driver to enable its IRQ. This undesirable coupling between drivers only exists because the OSS driver doesn't correctly handle all of its machspec IRQs.

Fix OSS handling of enable/disable for VIA1 IRQs (8 thru 15) which includes MAC_IRQ_ADB.

Back when I implemented pmac_zilog support I redefined IRQ_MAC_SCC incorrectly. Change this to a machspec IRQ so that it works on OSS.

Clean up the unused OSS audio IRQ and OSS_IRQLEV_* cruft that only confuses things.

Fix the OSS description in macints.c and remove an obsolete comment.

Don't enable the VIA1 irq before registering the handler.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

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m68k/mac: cleanup forward declarations

Move some forward declarations into header files and adjust includes.

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

m68k/mac: cleanup forward declarations

Move some forward declarations into header files and adjust includes.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

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m68k/mac: cleanup mac_irq_pending

mac_irq_pending() has only one caller (mac_esp.c). Nothing tests for Baboon, PSC or OSS pending interrupts. Until that need arises, let's keep it simple and remove

m68k/mac: cleanup mac_irq_pending

mac_irq_pending() has only one caller (mac_esp.c). Nothing tests for Baboon, PSC or OSS pending interrupts. Until that need arises, let's keep it simple and remove all the unused abstraction. Replace it with a routine to check for SCSI DRQ.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

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m68k/mac: cleanup mac_clear_irq

mac_clear_irq() is dead code and has been dead for as long as I can recall. On certain Mac models, certain irqs can't be cleared this way. Outside of irq dispatch, th

m68k/mac: cleanup mac_clear_irq

mac_clear_irq() is dead code and has been dead for as long as I can recall. On certain Mac models, certain irqs can't be cleared this way. Outside of irq dispatch, this code appears be unusable without busy loops or worse, and for irq dispatch we duplicate the same logic. Remove mac_clear_irq() and supporting code.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

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m68k/irq: Remove obsolete m68k irq framework

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

m68k/mac: Optimize interrupts using chain handlers

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

m68k/mac: Convert Mac to genirq

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

m68k/irq: Remove obsolete IRQ_FLG_* users

The m68k core irq code stopped honoring these flags during the irq
restructuring in 2006.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

m68k/irq: Rename {,__}m68k_handle_int()

- Rename m68k_handle_int() to generic_handle_irq(), and drop the unneeded
asmlinkage,
- Rename __m68k_handle_int() to do_IRQ().

Signed-off-by: Geert

m68k/irq: Rename {,__}m68k_handle_int()

- Rename m68k_handle_int() to generic_handle_irq(), and drop the unneeded
asmlinkage,
- Rename __m68k_handle_int() to do_IRQ().

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

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mac68k: replace mac68k SCC code with platform device

Remove the old 68k Mac serial port code and a lot of related cruft. Add
new SCC platform devices to mac 68k platform.

Signed-off-by: Finn Thain

mac68k: replace mac68k SCC code with platform device

Remove the old 68k Mac serial port code and a lot of related cruft. Add
new SCC platform devices to mac 68k platform.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

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m68k: mac core - Kill warn_unused_result warnings

warning: ignoring return value of 'request_irq', declared with attribute
warn_unused_result

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

m68k: machw.h cleanup

Remove some more cruft from machw.h and drop the #include where it isn't
needed.

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

m68k: machw.h cleanup

Remove some more cruft from machw.h and drop the #include where it isn't
needed.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

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m68k/mac/: possible cleanups

This patch contains the following possible cleanups:
- make the following needlessly global code (always) static:
- baboon.c: struct baboon
- baboon.c: baboon_irq()

m68k/mac/: possible cleanups

This patch contains the following possible cleanups:
- make the following needlessly global code (always) static:
- baboon.c: struct baboon
- baboon.c: baboon_irq()
- config.c: mac_orig_videoaddr
- config.c: mac_identify()
- config.c: mac_report_hardware()
- config.c: mac_debug_console_write()
- config.c: mac_sccb_console_write()
- config.c: mac_scca_console_write()
- config.c: mac_init_scc_port()
- oss.c: oss_irq()
- oss.c: oss_nubus_irq()
- psc.c: psc_debug_dump()
- psc.c: psc_dma_die_die_die()
- via.c: rbv_clear
- remove the unused bootparse.c
- #if 0 the following unused functions:
- config.c: mac_debugging_short()
- config.c: mac_debugging_long()
- remove the following unused code:
- config.c: mac_bisize
- config.c: mac_env
- config.c: mac_SCC_init_done
- config.c: mac_SCC_reset_done
- config.c: mac_init_scca_port()
- config.c: mac_init_sccb_port()

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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m68k: replace remaining __FUNCTION__ occurrences

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>

m68k: replace remaining __FUNCTION__ occurrences

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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spelling fixes: arch/m68k/

Spelling fixes in arch/m68k/.

Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Adrian Bunk <bunk@kernel.

spelling fixes: arch/m68k/

Spelling fixes in arch/m68k/.

Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Adrian Bunk <bunk@kernel.org>

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m68k: Mac IRQ cleanup

There are no slow IRQs on Macs since Roman Zippel's IRQ reorganisation that
went into 2.6.16 and removed mac_irq_list[] and the do_mac_irq_list()
dispatcher. (They were impleme

m68k: Mac IRQ cleanup

There are no slow IRQs on Macs since Roman Zippel's IRQ reorganisation that
went into 2.6.16 and removed mac_irq_list[] and the do_mac_irq_list()
dispatcher. (They were implemented in do_mac_irq_list() by lowering the IPL.)
Hence there's no more use for mutual exclusion in the Mac interrupt
dispatchers. Remove it.

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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