3 Commits

Author	SHA1	Message	Date
Zsolt Kajtar	eabb032930	fbdev: Refactoring the fbcon packed pixel drawing routines ... The original version duplicated more or less the same algorithms for both system and i/o memory. In this version the drawing algorithms (copy/fill/blit) are separate from the memory access (system and i/o). The two parts are getting combined in the loadable module sources. This also makes it more robust against wrong memory access type or alignment mistakes as there's no direct pointer access or arithmetic in the algorithm sources anymore. Due to liberal use of inlining the compiled result is a single function in all 6 cases, without unnecessary function calls. Unlike earlier the use of macros could be minimized as apparently both gcc and clang is capable now to do the same with inline functions just as well. What wasn't quite the same in the two variants is the support for pixel order reversing. This version is capable to do that for both system and I/O memory, and not only for the latter. As demand for low bits per pixel modes isn't high there's a configuration option to enable this separately for the CFB and SYS modules. The pixel reversing algorithm is different than earlier and was designed so that it can take advantage of bit order reversing instructions on architectures which have them. And even for higher bits per pixel modes like four bpp. One of the shortcomings of the earlier version was the incomplete support for foreign endian framebuffers. Now all three drawing algorithms produce correct output on both endians with native and foreign framebuffers. This is one of the important differences even if otherwise the algorithms don't look too different than before. All three routines work now with aligned native word accesses. As a consequence blitting isn't limited to 32 bits on 64 bit architectures as it was before. The old routines silently assumed that rows are a multiple of the word size. Due to how the new routines function this isn't a requirement any more and access will be done aligned regardless. However if the framebuffer is configured like that then some of the fast paths won't be available. As this code is supposed to be running on all supported architectures it wasn't optimized for a particular one. That doesn't mean I haven't looked at the disassembly. That's where I noticed that it isn't a good idea to use the fallback bitreversing code for example. The low bits per pixel modes should be faster than before as the new routines can blit 4 pixels at a time. On the higher bits per pixel modes I retained the specialized aligned routines so it should be more or less the same, except on 64 bit architectures. There the blitting word size is double now which means 32 BPP isn't done a single pixel a time now. The code was tested on x86, amd64, mips32 and mips64. The latter two in big endian configuration. Originally thought I can get away with the first two, but with such bit twisting code byte ordering is tricky and not really possible to get right without actually verifying it. While writing such routines isn't rocket science a lot of time was spent on making sure that pixel ordering, foreign byte order, various bits per pixels, cpu endianness and word size will give the expected result in all sorts of combinations without making it overly complicated or full with special cases. Signed-off-by: Zsolt Kajtar <soci@c64.rulez.org> Signed-off-by: Helge Deller <deller@gmx.de>	2025-03-26 22:39:21 +01:00
Greg Kroah-Hartman	b24413180f	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>	2017-11-02 11:10:55 +01:00
Tomi Valkeinen	19757fc843	fbdev: move fbdev core files to separate directory ... Instead of having fbdev framework core files at the root fbdev directory, mixed with random fbdev device drivers, move the fbdev core files to a separate core directory. This makes it much clearer which of the files are actually part of the fbdev framework, and which are part of device drivers. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Rob Clark <robdclark@gmail.com> Acked-by: Jingoo Han <jg1.han@samsung.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>	2014-04-17 08:10:19 +03:00