linux/include/asm-generic/io.h

1107 lines
22 KiB

lib: Add generic PIO mapping method 41f8bba7f555 ("of/pci: Add pci_register_io_range() and pci_pio_to_address()") added support for PCI I/O space mapped into CPU physical memory space. With that support, the I/O ranges configured for PCI/PCIe hosts on some architectures can be mapped to logical PIO and converted easily between CPU address and the corresponding logical PIO. Based on this, PCI I/O port space can be accessed via in/out accessors that use memory read/write. But on some platforms, there are bus hosts that access I/O port space with host-local I/O port addresses rather than memory addresses. Add a more generic I/O mapping method to support those devices. With this patch, both the CPU addresses and the host-local port can be mapped into the logical PIO space with different logical/fake PIOs. After this, all the I/O accesses to either PCI MMIO devices or host-local I/O peripherals can be unified into the existing I/O accessors defined in asm-generic/io.h and be redirected to the right device-specific hooks based on the input logical PIO. Tested-by: dann frazier <dann.frazier@canonical.com> Signed-off-by: Zhichang Yuan <yuanzhichang@hisilicon.com> Signed-off-by: Gabriele Paoloni <gabriele.paoloni@huawei.com> Signed-off-by: John Garry <john.garry@huawei.com> [bhelgaas: remove -EFAULT return from logic_pio_register_range() per https://lkml.kernel.org/r/20180403143909.GA21171@ulmo, fix NULL pointer checking per https://lkml.kernel.org/r/20180403211505.GA29612@embeddedor.com] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
2018-03-15 02:15:50 +08:00
x86/mm, asm-generic: Add IOMMU ioremap_uc() variant default We currently have no safe way of currently defining architecture agnostic IOMMU ioremap_*() variants. The trend is for folks to *assume* that ioremap_nocache() should be the default everywhere and then add this mapping on each architectures -- this is not correct today for a variety of reasons. We have two options: 1) Sit and wait for every architecture in Linux to get a an ioremap_*() variant defined before including it upstream. 2) Gather consensus on a safe architecture agnostic ioremap_*() default. Approach 1) introduces development latencies, and since 2) will take time and work on clarifying semantics the only remaining sensible thing to do to avoid issues is returning NULL on ioremap_*() variants. In order for this to work we must have all architectures declare their own ioremap_*() variants as defined. This will take some work, do this for ioremp_uc() to set the example as its only currently implemented on x86. Document all this. We only provide implementation support for ioremap_uc() as the other ioremap_*() variants are well defined all over the kernel for other architectures already. Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: arnd@arndb.de Cc: benh@kernel.crashing.org Cc: bp@suse.de Cc: dan.j.williams@intel.com Cc: geert@linux-m68k.org Cc: hch@lst.de Cc: hmh@hmh.eng.br Cc: jgross@suse.com Cc: linux-mm@kvack.org Cc: luto@amacapital.net Cc: mpe@ellerman.id.au Cc: mst@redhat.com Cc: ralf@linux-mips.org Cc: ross.zwisler@linux.intel.com Cc: stefan.bader@canonical.com Cc: tj@kernel.org Cc: tomi.valkeinen@ti.com Cc: toshi.kani@hp.com Link: http://lkml.kernel.org/r/1436488096-3165-1-git-send-email-mcgrof@do-not-panic.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-09 17:28:16 -07:00
x86/mm, asm-generic: Add IOMMU ioremap_uc() variant default We currently have no safe way of currently defining architecture agnostic IOMMU ioremap_*() variants. The trend is for folks to *assume* that ioremap_nocache() should be the default everywhere and then add this mapping on each architectures -- this is not correct today for a variety of reasons. We have two options: 1) Sit and wait for every architecture in Linux to get a an ioremap_*() variant defined before including it upstream. 2) Gather consensus on a safe architecture agnostic ioremap_*() default. Approach 1) introduces development latencies, and since 2) will take time and work on clarifying semantics the only remaining sensible thing to do to avoid issues is returning NULL on ioremap_*() variants. In order for this to work we must have all architectures declare their own ioremap_*() variants as defined. This will take some work, do this for ioremp_uc() to set the example as its only currently implemented on x86. Document all this. We only provide implementation support for ioremap_uc() as the other ioremap_*() variants are well defined all over the kernel for other architectures already. Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: arnd@arndb.de Cc: benh@kernel.crashing.org Cc: bp@suse.de Cc: dan.j.williams@intel.com Cc: geert@linux-m68k.org Cc: hch@lst.de Cc: hmh@hmh.eng.br Cc: jgross@suse.com Cc: linux-mm@kvack.org Cc: luto@amacapital.net Cc: mpe@ellerman.id.au Cc: mst@redhat.com Cc: ralf@linux-mips.org Cc: ross.zwisler@linux.intel.com Cc: stefan.bader@canonical.com Cc: tj@kernel.org Cc: tomi.valkeinen@ti.com Cc: toshi.kani@hp.com Link: http://lkml.kernel.org/r/1436488096-3165-1-git-send-email-mcgrof@do-not-panic.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-09 17:28:16 -07:00
x86/mm, asm-generic: Add IOMMU ioremap_uc() variant default We currently have no safe way of currently defining architecture agnostic IOMMU ioremap_*() variants. The trend is for folks to *assume* that ioremap_nocache() should be the default everywhere and then add this mapping on each architectures -- this is not correct today for a variety of reasons. We have two options: 1) Sit and wait for every architecture in Linux to get a an ioremap_*() variant defined before including it upstream. 2) Gather consensus on a safe architecture agnostic ioremap_*() default. Approach 1) introduces development latencies, and since 2) will take time and work on clarifying semantics the only remaining sensible thing to do to avoid issues is returning NULL on ioremap_*() variants. In order for this to work we must have all architectures declare their own ioremap_*() variants as defined. This will take some work, do this for ioremp_uc() to set the example as its only currently implemented on x86. Document all this. We only provide implementation support for ioremap_uc() as the other ioremap_*() variants are well defined all over the kernel for other architectures already. Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: arnd@arndb.de Cc: benh@kernel.crashing.org Cc: bp@suse.de Cc: dan.j.williams@intel.com Cc: geert@linux-m68k.org Cc: hch@lst.de Cc: hmh@hmh.eng.br Cc: jgross@suse.com Cc: linux-mm@kvack.org Cc: luto@amacapital.net Cc: mpe@ellerman.id.au Cc: mst@redhat.com Cc: ralf@linux-mips.org Cc: ross.zwisler@linux.intel.com Cc: stefan.bader@canonical.com Cc: tj@kernel.org Cc: tomi.valkeinen@ti.com Cc: toshi.kani@hp.com Link: http://lkml.kernel.org/r/1436488096-3165-1-git-send-email-mcgrof@do-not-panic.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-09 17:28:16 -07:00