kernel/linux.git/arch/powerpc/include/asm/synch.h, branch v6.12.80

powerpc: Change CONFIG_E500 to CONFIG_PPC_E500

2022-09-26T13:00:13+00:00

It will be used outside arch/powerpc, make it clear its a powerpc configuration item. And we already have CONFIG_PPC_E500MC, so that will make it more consistent. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/e63b22083c11c4300f4a82d3123a46e5fdd54fa6.1663606876.git.christophe.leroy@csgroup.eu

powerpc/44x: Fix build failure with GCC 12 (unrecognized opcode: `wrteei')

2022-07-27T11:36:06+00:00

Building ppc40x_defconfig leads to following error CC arch/powerpc/kernel/idle.o {standard input}: Assembler messages: {standard input}:67: Error: unrecognized opcode: `wrteei' {standard input}:78: Error: unrecognized opcode: `wrteei' Add -mcpu=440 by default and alternatively 464 and 476. Once that's done, -mcpu=powerpc is only for book3s/32 now. But then comes CC arch/powerpc/kernel/io.o {standard input}: Assembler messages: {standard input}:198: Error: unrecognized opcode: `eieio' {standard input}:230: Error: unrecognized opcode: `eieio' {standard input}:245: Error: unrecognized opcode: `eieio' {standard input}:254: Error: unrecognized opcode: `eieio' {standard input}:273: Error: unrecognized opcode: `eieio' {standard input}:396: Error: unrecognized opcode: `eieio' {standard input}:404: Error: unrecognized opcode: `eieio' {standard input}:423: Error: unrecognized opcode: `eieio' {standard input}:512: Error: unrecognized opcode: `eieio' {standard input}:520: Error: unrecognized opcode: `eieio' {standard input}:539: Error: unrecognized opcode: `eieio' {standard input}:628: Error: unrecognized opcode: `eieio' {standard input}:636: Error: unrecognized opcode: `eieio' {standard input}:655: Error: unrecognized opcode: `eieio' Fix it by replacing eieio by mbar on booke. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/b0d982e223314ed82ab959f5d4ad2c4c00bedb99.1657549153.git.christophe.leroy@csgroup.eu

powerpc/64s: Add cp_abort after tlbiel to invalidate copy-buffer address

2020-10-06T12:22:23+00:00

The copy buffer is implemented as a real address in the nest which is translated from EA by copy, and used for memory access by paste. This requires that it be invalidated by TLB invalidation. TLBIE does invalidate the copy buffer, but TLBIEL does not. Add cp_abort to the tlbiel sequence. Signed-off-by: Nicholas Piggin [mpe: Fixup whitespace and comment formatting] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200916030234.4110379-2-npiggin@gmail.com

powerpc: clean the inclusion of stringify.h

2018-07-30T12:48:17+00:00

Only include linux/stringify.h is files using __stringify() Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman

powerpc: move ASM_CONST and stringify_in_c() into asm-const.h

2018-07-30T12:48:16+00:00

This patch moves ASM_CONST() and stringify_in_c() into dedicated asm-const.h, then cleans all related inclusions. Signed-off-by: Christophe Leroy [mpe: asm-compat.h should include asm-const.h] Signed-off-by: Michael Ellerman

powerpc/64: Fix smp_wmb barrier definition use use lwsync consistently

2018-03-30T13:10:34+00:00

asm/barrier.h is not always included after asm/synch.h, which meant it was missing __SUBARCH_HAS_LWSYNC, so in some files smp_wmb() would be eieio when it should be lwsync. kernel/time/hrtimer.c is one case. __SUBARCH_HAS_LWSYNC is only used in one place, so just fold it in to where it's used. Previously with my small simulator config, 377 instances of eieio in the tree. After this patch there are 55. Fixes: 46d075be585e ("powerpc: Optimise smp_wmb") Cc: stable@vger.kernel.org # v2.6.29+ Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman

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

powerpc: Factor do_feature_fixup calls

2016-07-21T08:51:42+00:00

32 and 64-bit do a similar set of calls early on, we move it all to a single common function to make the boot code more readable. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman

powerpc: Make value-returning atomics fully ordered

2015-12-14T09:38:18+00:00

According to memory-barriers.txt: > Any atomic operation that modifies some state in memory and returns > information about the state (old or new) implies an SMP-conditional > general memory barrier (smp_mb()) on each side of the actual > operation ... Which mean these operations should be fully ordered. However on PPC, PPC_ATOMIC_ENTRY_BARRIER is the barrier before the actual operation, which is currently "lwsync" if SMP=y. The leading "lwsync" can not guarantee fully ordered atomics, according to Paul Mckenney: https://lkml.org/lkml/2015/10/14/970 To fix this, we define PPC_ATOMIC_ENTRY_BARRIER as "sync" to guarantee the fully-ordered semantics. This also makes futex atomics fully ordered, which can avoid possible memory ordering problems if userspace code relies on futex system call for fully ordered semantics. Fixes: b97021f85517 ("powerpc: Fix atomic_xxx_return barrier semantics") Cc: stable@vger.kernel.org # 3.2+ Signed-off-by: Boqun Feng Reviewed-by: Paul E. McKenney Acked-by: Peter Zijlstra (Intel) Signed-off-by: Michael Ellerman

powerpc: Fix atomic_xxx_return barrier semantics

2011-11-17T05:26:07+00:00

The Documentation/memory-barriers.txt document requires that atomic operations that return a value act as a memory barrier both before and after the actual atomic operation. Our current implementation doesn't guarantee this. More specifically, while a load following the isync can not be issued before stwcx. has completed, that completion doesn't architecturally means that the result of stwcx. is visible to other processors (or any previous stores for that matter) (typically, the other processors L1 caches can still hold the old value). This has caused an actual crash in RCU torture testing on Power 7 This fixes it by changing those atomic ops to use new macros instead of RELEASE/ACQUIRE barriers, called ATOMIC_ENTRY and ATMOIC_EXIT barriers, which are then defined respectively to lwsync and sync. I haven't had a chance to measure the performance impact (or rather what I measured with kernel compiles is in the noise, I yet have to find a more precise benchmark) Signed-off-by: Benjamin Herrenschmidt Acked-by: Paul E. McKenney