kernel/arch/m68k/mac/oss.c, branch linux-rolling-stable

m68k: mac: Add and use "mac.h"

2023-10-06T08:03:03Z

When building with W=1: arch/m68k/mac/iop.c:235:13: warning: no previous prototype for ‘iop_init’ [-Wmissing-prototypes] 235 | void __init iop_init(void) | ^~~~~~~~ arch/m68k/mac/via.c:112:13: warning: no previous prototype for ‘via_init’ [-Wmissing-prototypes] 111 | void __init via_init(void) | ^~~~~~~~ arch/m68k/mac/via.c:623:13: warning: no previous prototype for ‘via_init_clock’ [-Wmissing-prototypes] 593 | void __init via_init_clock(void) | ^~~~~~~~~~~~~~ arch/m68k/mac/oss.c:37:13: warning: no previous prototype for ‘oss_init’ [-Wmissing-prototypes] 37 | void __init oss_init(void) | ^~~~~~~~ arch/m68k/mac/psc.c:76:13: warning: no previous prototype for ‘psc_init’ [-Wmissing-prototypes] 76 | void __init psc_init(void) | ^~~~~~~~ arch/m68k/mac/baboon.c:25:13: warning: no previous prototype for ‘baboon_init’ [-Wmissing-prototypes] 25 | void __init baboon_init(void) | ^~~~~~~~~~~ arch/m68k/mac/macboing.c:155:6: warning: no previous prototype for ‘mac_mksound’ [-Wmissing-prototypes] 155 | void mac_mksound( unsigned int freq, unsigned int length ) | ^~~~~~~~~~~ arch/m68k/mac/misc.c:608:5: warning: no previous prototype for ‘mac_hwclk’ [-Wmissing-prototypes] 608 | int mac_hwclk(int op, struct rtc_time *t) | ^~~~~~~~~ Fix this by introducing a new header file "mac.h" for holding the prototypes of functions implemented in arch/m68k/mac/. Signed-off-by: Geert Uytterhoeven Acked-by: Arnd Bergmann Link: https://lore.kernel.org/r/d1fe0014a9e472a305333de4fa17f335c93d73af.1694613528.git.geert@linux-m68k.org

m68k/mac: Fix race conditions in OSS interrupt dispatch

2018-01-16T15:52:17Z

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 Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven

Merge tag 'm68k-for-v4.15-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k

2017-11-13T20:10:24Z

Pull m68k updates from Geert Uytterhoeven: - more printk modernization - various cleanups and fixes (incl. a race condition) for Mac - defconfig updates * tag 'm68k-for-v4.15-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k: m68k/defconfig: Update defconfigs for v4.14-rc7 m68k/mac: Add mutual exclusion for IOP interrupt polling m68k/mac: Disentangle VIA/RBV and NuBus initialization m68k/mac: Disentangle VIA and OSS initialization m68k/mac: More printk modernization

m68k/mac: Disentangle VIA/RBV and NuBus initialization

2017-11-09T22:02:57Z

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 Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven

m68k/mac: Disentangle VIA and OSS initialization

2017-11-09T22:02:56Z

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 Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven

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

2017-11-02T10:10:55Z

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 Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

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

2017-02-09T13:18:19Z

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 Signed-off-by: Geert Uytterhoeven

genirq: Remove irq argument from irq flow handlers

2015-09-16T13:47:51Z

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 Cc: Julia Lawall Cc: Jiang Liu

m68k/irq: Prepare irq handlers for irq argument removal

2015-08-01T06:07:22Z

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 Cc: Julia Lawall Cc: Geert Uytterhoeven Cc: linux-m68k@lists.linux-m68k.org

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

2015-03-30T08:14:34Z

Reported-by: David Binderman Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven