Merge tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull asm-generic fixes from Arnd Bergmann: "I have one regression fix for a minor build problem after the architecture removal series, plus a rework of the barriers in the readl/writel functions, thanks to work by Sinan Kaya: This started from a discussion on the linuxpcc and rdma mailing lists[1]. To summarize, we decided that architectures are responsible to serialize readl() and writel() accesses on a device MMIO space relative to DMA performed by that device. This series provides a pessimistic implementation of that behavior for asm-generic/io.h, which is in turn used by a number of architectures (h8300, microblaze, nios2, openrisc, s390, sparc, um, unicore32, and xtensa). Some of those presumably need no extra barriers, or something weaker than rmb()/wmb(), and they are advised to override the new default for better performance. For inb()/outb(), the same barriers are used, but architectures might want to add another barrier to outb() here if that can guarantee non-posted behavior (some architectures can, others cannot do that). The readl_relaxed()/writel_relaxed() family of functions retains the existing behavior with no extra barriers" [1] https://lists.ozlabs.org/pipermail/linuxppc-dev/2018-March/170481.html * tag 'asm-generic' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: io: change writeX_relaxed() to remove barriers io: change readX_relaxed() to remove barriers dts: remove cris & metag dts hard link file io: change inX() to have their own IO barrier overrides io: change outX() to have their own IO barrier overrides io: define stronger ordering for the default writeX() implementation io: define stronger ordering for the default readX() implementation io: define several IO & PIO barrier types for the asm-generic version
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