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2024-02-12PCI: Move pci_iomap.c to drivers/pci/Philipp Stanner
The entirety of pci_iomap.c is guarded by an #ifdef CONFIG_PCI. It, consequently, does not belong to lib/ because it is not generic infrastructure. Move pci_iomap.c to drivers/pci/ and implement the necessary changes to Makefiles and Kconfigs. Update MAINTAINERS file. Update Documentation. Link: https://lore.kernel.org/r/20240131090023.12331-3-pstanner@redhat.com [bhelgaas: squash in https://lore.kernel.org/r/20240212150934.24559-1-pstanner@redhat.com] Suggested-by: Danilo Krummrich <dakr@redhat.com> Signed-off-by: Philipp Stanner <pstanner@redhat.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de>
2023-11-23arch/*/io.h: remove ioremap_uc in some architecturesBaoquan He
ioremap_uc() is only meaningful on old x86-32 systems with the PAT extension, and on ia64 with its slightly unconventional ioremap() behavior. So remove the ioremap_uc() definition in architecutures other than x86 and ia64. These architectures all have asm-generic/io.h included and will have the default ioremap_uc() definition which returns NULL. This changes the existing behaviour, while no need to worry about any breakage because in the only callsite of ioremap_uc(), code has been adjusted to eliminate the impact. Please see atyfb_setup_generic() of drivers/video/fbdev/aty/atyfb_base.c. If any new invocation of ioremap_uc() need be added, please consider using ioremap() intead or adding a ARCH specific version if necessary. Signed-off-by: Baoquan He <bhe@redhat.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Acked-by: Helge Deller <deller@gmx.de> # parisc Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Acked-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> (SuperH) Cc: linux-alpha@vger.kernel.org Cc: linux-hexagon@vger.kernel.org Cc: linux-m68k@lists.linux-m68k.org Cc: linux-mips@vger.kernel.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2023-03-30docs: move x86 documentation into Documentation/arch/Jonathan Corbet
Move the x86 documentation under Documentation/arch/ as a way of cleaning up the top-level directory and making the structure of our docs more closely match the structure of the source directories it describes. All in-kernel references to the old paths have been updated. Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: linux-arch@vger.kernel.org Cc: x86@kernel.org Cc: Borislav Petkov <bp@alien8.de> Cc: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/lkml/20230315211523.108836-1-corbet@lwn.net/ Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-02-07dma-buf-map: Rename to iosys-mapLucas De Marchi
Rename struct dma_buf_map to struct iosys_map and corresponding APIs. Over time dma-buf-map grew up to more functionality than the one used by dma-buf: in fact it's just a shim layer to abstract system memory, that can be accessed via regular load and store, from IO memory that needs to be acessed via arch helpers. The idea is to extend this API so it can fulfill other needs, internal to a single driver. Example: in the i915 driver it's desired to share the implementation for integrated graphics, which uses mostly system memory, with discrete graphics, which may need to access IO memory. The conversion was mostly done with the following semantic patch: @r1@ @@ - struct dma_buf_map + struct iosys_map @r2@ @@ ( - DMA_BUF_MAP_INIT_VADDR + IOSYS_MAP_INIT_VADDR | - dma_buf_map_set_vaddr + iosys_map_set_vaddr | - dma_buf_map_set_vaddr_iomem + iosys_map_set_vaddr_iomem | - dma_buf_map_is_equal + iosys_map_is_equal | - dma_buf_map_is_null + iosys_map_is_null | - dma_buf_map_is_set + iosys_map_is_set | - dma_buf_map_clear + iosys_map_clear | - dma_buf_map_memcpy_to + iosys_map_memcpy_to | - dma_buf_map_incr + iosys_map_incr ) @@ @@ - #include <linux/dma-buf-map.h> + #include <linux/iosys-map.h> Then some files had their includes adjusted and some comments were update to remove mentions to dma-buf-map. Since this is not specific to dma-buf anymore, move the documentation to the "Bus-Independent Device Accesses" section. v2: - Squash patches v3: - Fix wrong removal of dma-buf.h from MAINTAINERS - Move documentation from dma-buf.rst to device-io.rst v4: - Change documentation title and level Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com> Acked-by: Christian König <christian.koenig@amd.com> Acked-by: Sumit Semwal <sumit.semwal@linaro.org> Acked-by: Thomas Zimmermann <tzimmermann@suse.de> Link: https://patchwork.freedesktop.org/patch/msgid/20220204170541.829227-1-lucas.demarchi@intel.com
2021-04-08docs: driver-api: device-io: Document ioremap() variants & access funcsHector Martin
This documents the newly introduced ioremap_np() along with all the other common ioremap() variants, and some higher-level abstractions available. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Hector Martin <marcan@marcan.st>
2021-04-08docs: driver-api: device-io: Document I/O access functionsArnd Bergmann
This adds more detailed descriptions of the various read/write primitives available for use with I/O memory/ports. Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Hector Martin <marcan@marcan.st>
2020-07-13Driver-API: Documentation: Replace deprecated :c:func: UsagePuranjay Mohan
Replace :c:func: with func() as the previous usage is deprecated. Signed-off-by: Puranjay Mohan <puranjay12@gmail.com> Link: https://lore.kernel.org/r/20200707053252.32703-1-puranjay12@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-04-08Documentation: Kill all references to mmiowb()Will Deacon
The guarantees provided by mmiowb() are now provided implicitly by spin_unlock(), so remove all references to this most confusing of barriers from our Documentation. Good riddance. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-01-31docs: Convert the deviceio template to RSTJonathan Corbet
Convert deviceiobook.tmpl to RST and incorporate it into the driver API manual. Like the rest of our documentation, this one could use some work. There's no mention of ioremap() and friends, no mention of io_read*() and friends. But we have nice documentation for all those folks writing new drivers that do port I/O :). The :c:func: notation has been left off of all the read*/write* functions. There's no kerneldoc comments for them anyway, so those links will never be live, and writing a bunch of repetitive "read a byte from I/O memory" comments lacks appeal. Cc: Matthew Wilcox <willy@infradead.org> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Signed-off-by: Jonathan Corbet <corbet@lwn.net>