kernel/git/stable/linux.git/arch/arm/mach-versatile/Kconfig, branch master

ARM: deprecate support for ARM1136r0

2026-07-03T18:36:07+00:00

This CPU revision remains a special case as it is now incompatible with CONFIG_SMP. Only the Nokia N8x0 is used in practice, and even that one is fairly rare these days, so let's plan to remove all of them after the 2026 LTS kernel release. Acked-by: Linus Walleij Acked-by: Vladimir Zapolskiy # Freescale i.MX31 Acked-by: Aaro Koskinen # OMAP Signed-off-by: Arnd Bergmann

ARM: rework ARM11 CPU selection logic

2026-07-03T18:36:07+00:00

Support for SMP on ARM1136r0 has been broken for a while, and nobody is working on fixing it. I had a plan to change ARMv6 support to no longer coexist in a common kernel with ARMv7 CPUs but instead ARMv5 and below. This would have addressed the problem, but after a recent mailing list discussion, we concluded that an easier approach is to just forbid ARM1136r0 CPU support on SMP-enabled kernels. This mainly affects users of the Nokia N800/N810 tablets using an OMAP2420 SoC, which is the only commercial product with an ARM1136r0 that is still supported by the kernel. The other machines that are still in the same hardware catogory are: - TI OMAP2420 H4 reference board - TI OMAP2430 SDP software development platform - Freescale/NXP i.MX31 Lite Development Kit - Buglabs i.MX31 Bug 1.x prototype - Arm Integrator/AP with CM1136JF-S core module To my knowledge, none of these have any actual users aside from reference boards being used to more easily test the platforms. There are also a few ARM1136r1 machines, which implement the ARMv6K SMP support (barriers, atomics and TLS): - Eukrea CPUIMX35 reference platform - Freescale/NXP i.MX35 Product Development Kit - ARM Integrator/CP/IM-LT3 with ARM1136J Core Tile - ARM Realview/EB with ARM1136J Core Tile Again, these are mainly reference implementations rather than actual products, but since they support ARMv6K, they should continue to work correctly in SMP-enabled kernels. For the ARM Core Tile, I have not found a datasheet but instead use the revision based on what the respective virtual models report. All the other ARMv6 platforms use an ARM1176 with ARMv6K, VMSAv7 and Trustzone support. To avoid the broken configuration, annotate the ARM1136 based machines with specific CPU_ARM1136R0 or CPU_ARM1136R2 symbols in Kconfig and make the r0 variants depend on !SMP. Link: https://lore.kernel.org/linux-arm-kernel/2831c5a6-cfbf-4fe0-b51c-0396e5b0aeb7@app.fastmail.com/T/ Acked-by: Linus Walleij Acked-by: Aaro Koskinen # OMAP Signed-off-by: Arnd Bergmann

arm: vexpress: Remove obsolete RTSM DCSCB support

2024-05-29T22:25:11+00:00

The Arm Versatile DCSCB support is unused as the compatible "arm,rtsm,dcscb" is unused in any .dts file. It was only ever implemented on a s/w model (RTSM). Signed-off-by: Rob Herring (Arm) Reviewed-by: Linus Walleij Link: https://lore.kernel.org/r/20240510123238.3904779-1-robh@kernel.org Signed-off-by: Sudeep Holla

ARM: Delete ARM11MPCore (ARM11 ARMv6K SMP) support

2023-12-22T11:43:16+00:00

This ARM11 SMP configuration was one of the first SMP configurations the ARM kernel supported, but it has the downside of odd DMA handling, odd cache tagging, and often (as of recent) completely broken cache handling on the ARM RealView PB11MPCore test chips. To boot the platform it was necessary to completely disable the cache. When it comes to the EB 11MPCore it is unclear if this ever worked. These reference designs are now the only ARMv6K SMP platforms. As only reference designs of purely academic interest remain, and since the special-cased DMA and PMU code is hard to maintain and doesn't really work, it is not really worth our time. Delete the ARM11MPCore support along with: - The special DMA quirk CONFIG_DMA_CACHE_RWFO that is only used on ARMv6K SMP, and we are the last ARMV6K system leaving the building and the cache handling is awkward, so good-bye. - The special PMU handling that was only used by ARM11MPCore. The following is left behind: - TIMER_OF_DECLARE(arm_twd_11mp, "arm,arm11mp-twd-timer", ...) in arch/arm/kernel/smp_twd.c, this is still in use by Marvell MMP3 arch/arm/boot/dts/marvell/mmp3.dtsi - IRQCHIP_DECLARE(arm11mp_gic, "arm,arm11mp-gic", ...) in drivers/irqchip/irq-gic.c, this is still in use by Marvell MMP3 arch/arm/boot/dts/marvell/mmp3.dtsi - A compatible for the arm11mpcore SCU, since this was mistakedly used for the Cortex-A9 version of RealView EB. These are unfortunate but will need to be kept around for compatibility. New Marvell-specific compatibles should however probably be added. Acked-by: Mark Rutland Reviewed-by: Arnd Bergmann Signed-off-by: Linus Walleij Acked-by: Liviu Dudau Link: https://lore.kernel.org/r/20231207-drop-11mpcore-v2-1-560b396f3bf5@linaro.org Signed-off-by: Arnd Bergmann

ata: clean up how architectures enable PATA_PLATFORM and PATA_OF_PLATFORM

2022-09-16T14:24:06+00:00

There are two options for platform device PATA support: PATA_PLATFORM: Generic platform device PATA support PATA_OF_PLATFORM: OpenFirmware platform device PATA support If an architecture allows the generic platform device PATA support, it shall select HAVE_PATA_PLATFORM. Then, Generic platform device PATA support is available and can be selected. If an architecture has OpenFirmware support, which it indicates by selecting OF, OpenFirmware platform device PATA support is available and can be selected. If OpenFirmware platform device PATA support is selected, then the functionality (code files) from Generic platform device PATA support needs to be integrated in the kernel build for the OpenFirmware platform device PATA support to work. Select PATA_PLATFORM in PATA_OF_PLATFORM to make sure the needed files are added in the build. So, architectures with OpenFirmware support, do not need to additionally select HAVE_PATA_PLATFORM. It is only needed by architecture that want the non-OF pata-platform module. Reflect this way of intended use of config symbols in the ata Kconfig and adjust all architecture definitions. This follows the suggestion from Arnd Bergmann (see Link). Suggested-by: Arnd Bergmann Link: https://lore.kernel.org/all/4b33bffc-2b6d-46b4-9f1d-d18e55975a5a@www.fastmail.com/ Signed-off-by: Lukas Bulwahn Reviewed-by: Arnd Bergmann Signed-off-by: Damien Le Moal

ARM: rework endianess selection

2022-04-08T15:20:54+00:00

Choosing big-endian vs little-endian kernels in Kconfig has not worked correctly since the introduction of CONFIG_ARCH_MULTIPLATFORM a long time ago. The problems is that CONFIG_BIG_ENDIAN depends on ARCH_SUPPORTS_BIG_ENDIAN, which can set by any one platform in the config, but would actually have to be supported by all of them. This was mostly ok for ARMv6/ARMv7 builds, since these are BE8 and tend to just work aside from problems in nonportable device drivers. For ARMv4/v5 machines, CONFIG_BIG_ENDIAN and CONFIG_ARCH_MULTIPLATFORM were never set together, so this was disabled on all those machines except for IXP4xx. As IXP4xx can now become part of ARCH_MULTIPLATFORM, it seems better to formalize this logic: all ARMv4/v5 platforms get an explicit dependency on being either big-endian (ixp4xx) or little-endian (the rest). We may want to fix ixp4xx in the future to support both, but it does not work in LE mode at the moment. For the ARMv6/v7 platforms, there are two ways this could be handled a) allow both modes only for platforms selecting 'ARCH_SUPPORTS_BIG_ENDIAN' today, but only LE mode for the others, given that these were added intentionally at some point. b) allow both modes everwhere, given that it was already possible to build that way by e.g. selecting ARCH_VIRT, and that the list is not an accurate reflection of which platforms may or may not work. Out of these, I picked b) because it seemed slighly more logical to me. Signed-off-by: Arnd Bergmann

ARM: versatile: move integrator/realview/vexpress to versatile

2022-04-04T08:22:37+00:00

These are all fairly small platforms by now, and they are closely related. Just move them all into a single directory. Cc: Linus Walleij Cc: Liviu Dudau Cc: Lorenzo Pieralisi Tested-by: Sudeep Holla Acked-by: Sudeep Holla Signed-off-by: Arnd Bergmann

clk: versatile: Rename ICST to CLK_ICST

2021-10-15T01:00:25+00:00

For consistency, prefix the ICST config option with CLK as all other clock source drivers have. Signed-off-by: Jean Delvare Cc: Linus Walleij Cc: Michael Turquette Cc: Stephen Boyd Reviewed-by: Linus Walleij Link: https://lore.kernel.org/r/20210901180833.4558932d@endymion Signed-off-by: Stephen Boyd

clk: versatile: Rework kconfig structure

2020-05-05T16:43:14+00:00

CONFIG_COMMON_CLK_VERSATILE doesn't really do anything other than hiding Arm Ltd reference platform clock drivers. It is both selected by the platforms that need it and has a 'depends on' for those platforms. Let's drop the selects and convert CONFIG_COMMON_CLK_VERSATILE into a menuconfig entry. With this make CONFIG_ICST visible. Move the 'select REGMAP_MMIO' to the drivers that require it (SP810 did not). This also has the side effect of enabling CONFIG_ICST for COMPILE_TEST as it was not visible before. Cc: Catalin Marinas Cc: Will Deacon Cc: Liviu Dudau Cc: Lorenzo Pieralisi Cc: Linus Walleij Reviewed-by: Sudeep Holla Reviewed-by: Stephen Boyd Signed-off-by: Rob Herring

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

2017-11-02T10:10:55+00:00

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