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* arch: Remove Itanium (IA-64) architectureArd Biesheuvel2023-09-111-99/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Itanium architecture is obsolete, and an informal survey [0] reveals that any residual use of Itanium hardware in production is mostly HP-UX or OpenVMS based. The use of Linux on Itanium appears to be limited to enthusiasts that occasionally boot a fresh Linux kernel to see whether things are still working as intended, and perhaps to churn out some distro packages that are rarely used in practice. None of the original companies behind Itanium still produce or support any hardware or software for the architecture, and it is listed as 'Orphaned' in the MAINTAINERS file, as apparently, none of the engineers that contributed on behalf of those companies (nor anyone else, for that matter) have been willing to support or maintain the architecture upstream or even be responsible for applying the odd fix. The Intel firmware team removed all IA-64 support from the Tianocore/EDK2 reference implementation of EFI in 2018. (Itanium is the original architecture for which EFI was developed, and the way Linux supports it deviates significantly from other architectures.) Some distros, such as Debian and Gentoo, still maintain [unofficial] ia64 ports, but many have dropped support years ago. While the argument is being made [1] that there is a 'for the common good' angle to being able to build and run existing projects such as the Grid Community Toolkit [2] on Itanium for interoperability testing, the fact remains that none of those projects are known to be deployed on Linux/ia64, and very few people actually have access to such a system in the first place. Even if there were ways imaginable in which Linux/ia64 could be put to good use today, what matters is whether anyone is actually doing that, and this does not appear to be the case. There are no emulators widely available, and so boot testing Itanium is generally infeasible for ordinary contributors. GCC still supports IA-64 but its compile farm [3] no longer has any IA-64 machines. GLIBC would like to get rid of IA-64 [4] too because it would permit some overdue code cleanups. In summary, the benefits to the ecosystem of having IA-64 be part of it are mostly theoretical, whereas the maintenance overhead of keeping it supported is real. So let's rip off the band aid, and remove the IA-64 arch code entirely. This follows the timeline proposed by the Debian/ia64 maintainer [5], which removes support in a controlled manner, leaving IA-64 in a known good state in the most recent LTS release. Other projects will follow once the kernel support is removed. [0] https://lore.kernel.org/all/CAMj1kXFCMh_578jniKpUtx_j8ByHnt=s7S+yQ+vGbKt9ud7+kQ@mail.gmail.com/ [1] https://lore.kernel.org/all/0075883c-7c51-00f5-2c2d-5119c1820410@web.de/ [2] https://gridcf.org/gct-docs/latest/index.html [3] https://cfarm.tetaneutral.net/machines/list/ [4] https://lore.kernel.org/all/87bkiilpc4.fsf@mid.deneb.enyo.de/ [5] https://lore.kernel.org/all/ff58a3e76e5102c94bb5946d99187b358def688a.camel@physik.fu-berlin.de/ Acked-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
* ia64: replace #include <asm/export.h> with #include <linux/export.h>Masahiro Yamada2023-08-221-1/+1
| | | | | | | | | | | | Commit ddb5cdbafaaa ("kbuild: generate KSYMTAB entries by modpost") deprecated <asm/export.h>, which is now a wrapper of <linux/export.h>. Replace #include <asm/export.h> with #include <linux/export.h>. After all the <asm/export.h> lines are converted, <asm/export.h> and <asm-generic/export.h> will be removed. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
* treewide: Add SPDX license identifier for missed filesThomas Gleixner2019-05-211-0/+1
| | | | | | | | | | | | | | | | | Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ia64: move exports to definitionsAl Viro2016-08-071-0/+2
| | | | | | | | | | | | | | Here we have another kind of deviation from the default case - a difference between exporting functions and non-functions. EXPORT_DATA_SYMBOL... is really different from EXPORT_SYMBOL... on ia64, and we need to use the right one when moving exports from *.c where C compiler has the required information to *.S, where we need to supply it manually. parisc64 will be another one like that. Tested-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* [IA64] esi-supportDavid Mosberger-Tang2006-06-211-0/+96
Add support for making ESI calls [1]. ESI stands for "Extensible SAL specification" and is basically a way for invoking firmware subroutines which are identified by a GUID. I don't know whether ESI is used by vendors other than HP (if you do, please let me know) but as firmware "backdoors" go, this seems one of the cleaner methods, so it seems reasonable to support it, even though I'm not aware of any publicly documented ESI calls. I'd have liked to make the ESI module completely stand-alone, but unfortunately that is not easily (or not at all) possible because in order to make ESI calls in physical mode, a small stub similar to the EFI stub is needed in the kernel proper. I did try to create a stub that would work in user-level, but it quickly got ugly beyond recognition (e.g., the stub had to make assumptions about how the module-loader generated call-stubs work) and I didn't even get it to work (that's probably fixable, but I didn't bother because I concluded it was too ugly anyhow). While it's not terribly elegant to have kernel code which isn't actively used in the kernel proper, I think it might be worth making an exception here for two reasons: the code is trivially small (all that's really needed is esi_stub.S) and by including it in the normal kernel distro, it might encourage other OEMs to also use ESI, which I think would be far better than each inventing their own firmware "backdoor". The code was originally written by Alex. I just massaged and packaged it a bit (and perhaps messed up some things along the way...). Changes since first version of patch that was posted to mailing list: * Export ia64_esi_call and ia64_esi_call_phys() as GPL symbols. * Disallow building esi.c as a module for now. Building as a module would currently lead to an unresolved reference to "sal_lock" on SMP kernels because that symbol doesn't get exported. * Export esi_call_phys() only if ESI is enabled. * Remove internal stuff from esi.h and add a "proc_type" argument to ia64_esi_call() such that serialization-requirements can be expressed (ESI follows SAL here, where procedure calls may have to be serialized, are MP-safe, or MP-safe andr reentrant). [1] h21007.www2.hp.com/dspp/tech/tech_TechDocumentDetailPage_IDX/1,1701,919,00.html Signed-off-by: David Mosberger <David.Mosberger@acm.org> Signed-off-by: Alex Williamson <alex.williamson@hp.com> Signed-off-by: Tony Luck <tony.luck@intel.com>