Andrea Parri b374684018 riscv,mmio: Fix readX()-to-delay() ordering ... commit 4eb2eb1b4c0eb07793c240744843498564a67b83 upstream. Section 2.1 of the Platform Specification [1] states: Unless otherwise specified by a given I/O device, I/O devices are on ordering channel 0 (i.e., they are point-to-point strongly ordered). which is not sufficient to guarantee that a readX() by a hart completes before a subsequent delay() on the same hart (cf. memory-barriers.txt, "Kernel I/O barrier effects"). Set the I(nput) bit in __io_ar() to restore the ordering, align inline comments. [1] https://github.com/riscv/riscv-platform-specs Signed-off-by: Andrea Parri <parri.andrea@gmail.com> Link: https://lore.kernel.org/r/20230803042738.5937-1-parri.andrea@gmail.com Fixes: fab957c11e ("RISC-V: Atomic and Locking Code") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2023-08-16 18:27:21 +02:00
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asm	riscv,mmio: Fix readX()-to-delay() ordering	2023-08-16 18:27:21 +02:00
uapi/asm	riscv: Bump COMMAND_LINE_SIZE value to 1024	2023-03-30 12:49:16 +02:00