Commit Graph

9 Commits

Author SHA1 Message Date
Palmer Dabbelt 52e7c52d2d
RISC-V: Stop relying on GCC's register allocator's hueristics
GCC allows users to hint to the register allocation that a variable should be
placed in a register by using a syntax along the lines of

    function(...) {
        register long in_REG __asm__("REG");
    }

We've abused this a bit throughout the RISC-V port to access fixed registers
directly as C variables.  In practice it's never going to blow up because GCC
isn't going to allocate these registers, but it's not a well defined syntax so
we really shouldn't be relying upon this.  Luckily there is a very similar but
well defined syntax that allows us to still access these registers directly as
C variables, which is to simply declare the register variables globally.  For
fixed variables this doesn't change the ABI.

LLVM disallows this ambiguous syntax, so this isn't just strictly a formatting
change.

Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-03 10:28:13 -08:00
Mao Han dbeb90b0c1 riscv: Add perf callchain support
This patch add support for perf callchain sampling on riscv platforms.
The return address of leaf function is retrieved from pt_regs as
it is not saved in the outmost frame.

Signed-off-by: Mao Han <han_mao@c-sky.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: linux-riscv <linux-riscv@lists.infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Guo Ren <guoren@kernel.org>
Tested-by: Greentime Hu <greentime.hu@sifive.com>
[paul.walmsley@sifive.com: fixed some 'checkpatch.pl --strict' issues;
 fixed patch description spelling]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-09-04 12:43:00 -07:00
Thomas Gleixner 1802d0beec treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 655 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:41 -07:00
Linus Torvalds b0bb1269b9 RISC-V Patches for the 5.2 Merge Window, Part 1 v3
This patch set contains an assortment of RISC-V related patches that I'd
 like to target for the 5.2 merge window.  Most of the patches are
 cleanups, but there are a handful of user-visible changes:
 
 * The nosmp and nr_cpus command-line arguments are now supported, which
   work like normal.
 * The SBI console no longer installs itself as a preferred console, we
   rely on standard mechanisms (/chosen, command-line, hueristics)
   instead.
 * sfence_remove_sfence_vma{,_asid} now pass their arguments along to the
   SBI call.
 * Modules now support BUG().
 * A missing sfence.vma during boot has been added.  This bug only
   manifests during boot.
 * The arch/riscv support for SiFive's L2 cache controller has been
   merged, which should un-block the EDAC framework work.
 
 I've only tested this on QEMU again, as I didn't have time to get things
 running on the Unleashed.  The latest master from this morning merges in
 cleanly and passes the tests as well.
 
 This patch set rebased my "5.2 MW, Part 1" patch set which includes an
 erronous empty file.  It's also a rebase of my "5.2 MW, Part 2" patch
 set, in which I managed to create another file while attempting to
 remove the empty file.
 
 Sorry for all the noise!
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCAAxFiEEAM520YNJYN/OiG3470yhUCzLq0EFAlzeLhUTHHBhbG1lckBk
 YWJiZWx0LmNvbQAKCRDvTKFQLMurQXV/D/9nz8KYxNKOVIXft27mw93Qnx5joblg
 fibA7nGDuxCszSC3tfyaROJZuGKe1G24vP4RG7aVs+iwRmmFhtVdPwm7ZvIr+DfU
 a5mzwWkxhMZP8lgxMAIn7iM/NWrBm7rWdGTU0BYjHlGkQ5z3WA67rU/r/vrowhUN
 zK1U/ATLvFWDJv5rdDj8/T2rDJzWtAsuy2qlmQN30CCJoOXXgIdAj+fVG4IYoxO9
 2+NFJU4Y0a+YczWW3qaGFjTaYYt/sNr/uA8AoBNqV1NvsopK1UO3txbcfJwvZZC3
 JFU9WBjC7xuF2ihMWecIZ7XljZeqhlsP7lZDizatQ/mdL9k7+6elk1sdcNLC23dN
 VWJakudE42dISCwSh49fAbeNSl/3R5VWSlZmVO18gsmslkGa4FwuoKjklnxx7hYx
 fQfvaqMIEXy3YmKtmFneUXLdcGoWOjV0FfDh5Ye582tAmB2TzvgEJHPJI7suUA/a
 RkZHcmVJTSRBMe2fS0qkYxy/wdIDtRW2yjypssl9G6zQPPCVW+maD70m/9oVdsgm
 IL8MpoDxW0uAYsV8Ctt1/+Ux+BObMADIml/1HPQyBRA0qhorQQWk0TcbjEXeIShs
 OOG8byAQUJx98z62zrKQ53+Pxdevcja6uKxu3f0yEHxl19dBJdT2BM6rjs3sO1hi
 c3tX/U8o39H0Kg==
 =mZwx
 -----END PGP SIGNATURE-----

Merge tag 'riscv-for-linus-5.2-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux

Pull RISC-V updates from Palmer Dabbelt:
 "This contains an assortment of RISC-V related patches that I'd like to
  target for the 5.2 merge window. Most of the patches are cleanups, but
  there are a handful of user-visible changes:

   - The nosmp and nr_cpus command-line arguments are now supported,
     which work like normal.

   - The SBI console no longer installs itself as a preferred console,
     we rely on standard mechanisms (/chosen, command-line, hueristics)
     instead.

   - sfence_remove_sfence_vma{,_asid} now pass their arguments along to
     the SBI call.

   - Modules now support BUG().

   - A missing sfence.vma during boot has been added. This bug only
     manifests during boot.

   - The arch/riscv support for SiFive's L2 cache controller has been
     merged, which should un-block the EDAC framework work.

  I've only tested this on QEMU again, as I didn't have time to get
  things running on the Unleashed. The latest master from this morning
  merges in cleanly and passes the tests as well"

* tag 'riscv-for-linus-5.2-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: (31 commits)
  riscv: fix locking violation in page fault handler
  RISC-V: sifive_l2_cache: Add L2 cache controller driver for SiFive SoCs
  RISC-V: Add DT documentation for SiFive L2 Cache Controller
  RISC-V: Avoid using invalid intermediate translations
  riscv: Support BUG() in kernel module
  riscv: Add the support for c.ebreak check in is_valid_bugaddr()
  riscv: support trap-based WARN()
  riscv: fix sbi_remote_sfence_vma{,_asid}.
  riscv: move switch_mm to its own file
  riscv: move flush_icache_{all,mm} to cacheflush.c
  tty: Don't force RISCV SBI console as preferred console
  RISC-V: Access CSRs using CSR numbers
  RISC-V: Add interrupt related SCAUSE defines in asm/csr.h
  RISC-V: Use tabs to align macro values in asm/csr.h
  RISC-V: Fix minor checkpatch issues.
  RISC-V: Support nr_cpus command line option.
  RISC-V: Implement nosmp commandline option.
  RISC-V: Add RISC-V specific arch_match_cpu_phys_id
  riscv: vdso: drop unnecessary cc-ldoption
  riscv: call pm_power_off from machine_halt / machine_power_off
  ...
2019-05-19 09:56:36 -07:00
Christoph Hellwig 6ab77af4b0
riscv: remove duplicate macros from ptrace.h
No need to have two names for the same thing.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-04-25 14:51:11 -07:00
Christoph Hellwig 877425424d
riscv: remove unreachable !HAVE_FUNCTION_GRAPH_RET_ADDR_PTR code
HAVE_FUNCTION_GRAPH_RET_ADDR_PTR is always defined for RISC-V.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-04-25 14:51:11 -07:00
Thomas Gleixner fa9833992d riscv/stacktrace: Remove the pointless ULONG_MAX marker
Terminating the last trace entry with ULONG_MAX is a completely pointless
exercise and none of the consumers can rely on it because it's
inconsistently implemented across architectures. In fact quite some of the
callers remove the entry and adjust stack_trace.nr_entries afterwards.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: linux-riscv@lists.infradead.org
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Link: https://lkml.kernel.org/r/20190410103644.131061192@linutronix.de
2019-04-14 19:58:28 +02:00
Alan Kao b785ec129b
riscv/ftrace: Add HAVE_FUNCTION_GRAPH_RET_ADDR_PTR support
In walk_stackframe, the pc now receives the address from calling
ftrace_graph_ret_addr instead of manual calculation.

Note that the original calculation,
        pc = frame->ra - 4
is buggy when the instruction at the return address happened to be a
compressed inst. But since it is not a critical part of ftrace, it is
ignored for now to ease the review process.

Cc: Greentime Hu <greentime@andestech.com>
Signed-off-by: Alan Kao <alankao@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-04-02 19:59:13 -07:00
Palmer Dabbelt 5d8544e2d0 RISC-V: Generic library routines and assembly
This patch contains code that is more specific to the RISC-V ISA than it
is to Linux.  It contains string and math operations, C wrappers for
various assembly instructions, stack walking code, and uaccess.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2017-09-26 15:26:45 -07:00