Pull RISC-V updates from Palmer Dabbelt:
"This contains the fixes we'd like to target for the 4.16 merge window.
It's not as much as I was originally hoping to do but between glibc,
the chip, and FOSDEM there just wasn't enough time to get everything
put together. As such, this merge window is essentially just going to
be small changes. This includes mostly cleanups:
- A build fix failure to the audit test cases.
RISC-V doesn't have renameat because the generic syscall ABI moved
to renameat2 by the time of our port. The syscall audit test cases
don't understand this, so I added a trivial fix. This went through
mailing list review during the 4.15 merge window, but nobody has
picked it up so I think it's best to just do this here.
- The removal of our command-line argument processing code. The
"mem_end" stuff was broken and the rest duplicated generic device
tree code. The generic code was already being called.
- Some unused/redundant code has been removed, including
__ARCH_HAVE_MMU, current_pgdir, and the initialization of
init_mm.pgd.
- SUM is disabled upon taking a trap, which means that user memory is
protected during traps taking inside copy_{to,from}_user().
- The sptbr CSR has been renamed to satp in C code. We haven't
changed the assembly code in order to maintain compatibility with
binutils 2.29, which doesn't understand the new name.
Additionally, we're adding some new features:
- Basic ftrace support, thanks to Alan Kao!
- Support for ZONE_DMA32.
This is necessary for all the normal reasons, but also to deal with
a deficiency in the Xilinx PCIe controller we're using on our
FPGA-based systems. While the ZONE_DMA32 addition should be
sufficient for most uses, it doesn't complete the fix for the
Xilinx controller.
- TLB shootdowns now only target the harts where they're necessary,
instead of applying to all harts in the system.
These patches have all been sitting on our linux-next branch for a
while now. Due to time constraints this is all I feel comfortable
submitting during the 4.16 merge window, hopefully we'll do better
next time!"
[ Note to self: "harts" is RISC-V speak for "hardware threads". I had
to look that up. - Linus ]
* tag 'riscv-for-linus-4.16-merge_window' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux:
riscv: inline set_pgdir into its only caller
riscv: rename sptbr to satp
riscv: don't read back satp in paging_init
riscv: remove the unused current_pgdir function
riscv: add ZONE_DMA32
RISC-V: Limit the scope of TLB shootdowns
riscv: disable SUM in the exception handler
riscv: remove redundant unlikely()
riscv: remove unused __ARCH_HAVE_MMU define
riscv/ftrace: Add basic support
RISC-V: Remove mem_end command line processing
RISC-V: Remove duplicate command-line parsing logic
audit: Avoid build failures on systems without renameat
This patch allows devices that require memory that can be addressed
using 32-bit addresses to work easily on RISC-V systems. The newly
improved dma-direct ops will tap into this pool automatically for
32-bit addressing.
Based on an earlier patch from Wesley W. Terpstra.
CC: Wesley W. Terpstra <terpstra@sifive.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This patch contains basic ftrace support for RV64I platform.
Specifically, function tracer (HAVE_FUNCTION_TRACER), function graph
tracer (HAVE_FUNCTION_GRAPH_TRACER), and a frame pointer test
(HAVE_FUNCTION_GRAPH_FP_TEST) are implemented following the
instructions in Documentation/trace/ftrace-design.txt.
Note that the functions in both ftrace.c and setup.c should not be
hooked with the compiler's -pg option: to prevent infinite self-
referencing for the former, and to ignore early setup stuff for the
latter.
Signed-off-by: Alan Kao <alankao@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
The trivial direct mapping implementation already does a virtual to
physical translation which isn't strictly a noop, and will soon learn
to do non-direct but linear physical to dma translations through the
device offset and a few small tricks. Rename it to a better fitting
name.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
This patch contains all the build infrastructure that actually enables
the RISC-V port. This includes Makefiles, linker scripts, and Kconfig
files. It also contains the only top-level change, which adds RISC-V to
the list of architectures that need a sed run to produce the ARCH
variable when building locally.
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
