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2020-05-07logic_pio: Use _inX() and _outX()John Garry
Use _inX() and _outX(), which include memory barriers which may be overridden per arch. Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
2020-05-07logic_pio: Improve macro argument nameJohn Garry
Macro argument "bw" is used for building byte, word, and long-based functions. Use "bwl" instead, to include long. Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
2019-11-05lib: logic_pio: Enforce LOGIC_PIO_INDIRECT region ops are set at registrationJohn Garry
Since the only LOGIC_PIO_INDIRECT host (hisi-lpc) now sets the ops prior to registration, enforce this check for accessors ops at registration instead of in the IO port accessors to simplify and marginally optimise the code. A slight misalignment is also tidied. Also add myself as an author. Suggested-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
2019-08-13lib: logic_pio: Add logic_pio_unregister_range()John Garry
Add a function to unregister a logical PIO range. Logical PIO space can still be leaked when unregistering certain LOGIC_PIO_CPU_MMIO regions, but this acceptable for now since there are no callers to unregister LOGIC_PIO_CPU_MMIO regions, and the logical PIO region allocation scheme would need significant work to improve this. Cc: stable@vger.kernel.org Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
2019-08-13lib: logic_pio: Avoid possible overlap for unregistering regionsJohn Garry
The code was originally written to not support unregistering logical PIO regions. To accommodate supporting unregistering logical PIO regions, subtly modify LOGIC_PIO_CPU_MMIO region registration code, such that the "end" of the registered regions is the "end" of the last region, and not the sum of the sizes of all the registered regions. Cc: stable@vger.kernel.org Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
2019-08-13lib: logic_pio: Fix RCU usageJohn Garry
The traversing of io_range_list with list_for_each_entry_rcu() is not properly protected by rcu_read_lock() and rcu_read_unlock(), so add them. These functions mark the critical section scope where the list is protected for the reader, it cannot be "reclaimed". Any updater - in this case, the logical PIO registration functions - cannot update the list until the reader exits this critical section. In addition, the list traversing used in logic_pio_register_range() does not need to use the rcu variant. This is because we are already using io_range_mutex to guarantee mutual exclusion from mutating the list. Cc: stable@vger.kernel.org Fixes: 031e3601869c ("lib: Add generic PIO mapping method") Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
2018-03-21lib: Add generic PIO mapping methodZhichang Yuan
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>