1 Commits

Author	SHA1	Message	Date
Zhichang Yuan	031e360186	lib: Add generic PIO mapping method ... 41f8bba7f5 ("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>	2018-03-21 17:18:34 -05:00