The address of external symbols will locate more than 32-bit offset
in 64-bit kernel with sv39 or sv48 virtual addressing.
Module loader emits the GOT and PLT entries for data symbols and
function symbols respectively.
The PLT entry is a trampoline code for jumping to the 64-bit
real address. The GOT entry is just the data symbol address.
Signed-off-by: Zong Li <zong@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Atomics present the same issue with locking: release and acquire
variants need to be strengthened to meet the constraints defined
by the Linux-kernel memory consistency model [1].
Atomics present a further issue: implementations of atomics such
as atomic_cmpxchg() and atomic_add_unless() rely on LR/SC pairs,
which do not give full-ordering with .aqrl; for example, current
implementations allow the "lr-sc-aqrl-pair-vs-full-barrier" test
below to end up with the state indicated in the "exists" clause.
In order to "synchronize" LKMM and RISC-V's implementation, this
commit strengthens the implementations of the atomics operations
by replacing .rl and .aq with the use of ("lightweigth") fences,
and by replacing .aqrl LR/SC pairs in sequences such as:
0: lr.w.aqrl %0, %addr
bne %0, %old, 1f
...
sc.w.aqrl %1, %new, %addr
bnez %1, 0b
1:
with sequences of the form:
0: lr.w %0, %addr
bne %0, %old, 1f
...
sc.w.rl %1, %new, %addr /* SC-release */
bnez %1, 0b
fence rw, rw /* "full" fence */
1:
following Daniel's suggestion.
These modifications were validated with simulation of the RISC-V
memory consistency model.
C lr-sc-aqrl-pair-vs-full-barrier
{}
P0(int *x, int *y, atomic_t *u)
{
int r0;
int r1;
WRITE_ONCE(*x, 1);
r0 = atomic_cmpxchg(u, 0, 1);
r1 = READ_ONCE(*y);
}
P1(int *x, int *y, atomic_t *v)
{
int r0;
int r1;
WRITE_ONCE(*y, 1);
r0 = atomic_cmpxchg(v, 0, 1);
r1 = READ_ONCE(*x);
}
exists (u=1 /\ v=1 /\ 0:r1=0 /\ 1:r1=0)
[1] https://marc.info/?l=linux-kernel&m=151930201102853&w=2https://groups.google.com/a/groups.riscv.org/forum/#!topic/isa-dev/hKywNHBkAXMhttps://marc.info/?l=linux-kernel&m=151633436614259&w=2
Suggested-by: Daniel Lustig <dlustig@nvidia.com>
Signed-off-by: Andrea Parri <parri.andrea@gmail.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <albert@sifive.com>
Cc: Daniel Lustig <dlustig@nvidia.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jade Alglave <j.alglave@ucl.ac.uk>
Cc: Luc Maranget <luc.maranget@inria.fr>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Akira Yokosawa <akiyks@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-riscv@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Current implementations map locking operations using .rl and .aq
annotations. However, this mapping is unsound w.r.t. the kernel
memory consistency model (LKMM) [1]:
Referring to the "unlock-lock-read-ordering" test reported below,
Daniel wrote:
"I think an RCpc interpretation of .aq and .rl would in fact
allow the two normal loads in P1 to be reordered [...]
The intuition would be that the amoswap.w.aq can forward from
the amoswap.w.rl while that's still in the store buffer, and
then the lw x3,0(x4) can also perform while the amoswap.w.rl
is still in the store buffer, all before the l1 x1,0(x2)
executes. That's not forbidden unless the amoswaps are RCsc,
unless I'm missing something.
Likewise even if the unlock()/lock() is between two stores.
A control dependency might originate from the load part of
the amoswap.w.aq, but there still would have to be something
to ensure that this load part in fact performs after the store
part of the amoswap.w.rl performs globally, and that's not
automatic under RCpc."
Simulation of the RISC-V memory consistency model confirmed this
expectation.
In order to "synchronize" LKMM and RISC-V's implementation, this
commit strengthens the implementations of the locking operations
by replacing .rl and .aq with the use of ("lightweigth") fences,
resp., "fence rw, w" and "fence r , rw".
C unlock-lock-read-ordering
{}
/* s initially owned by P1 */
P0(int *x, int *y)
{
WRITE_ONCE(*x, 1);
smp_wmb();
WRITE_ONCE(*y, 1);
}
P1(int *x, int *y, spinlock_t *s)
{
int r0;
int r1;
r0 = READ_ONCE(*y);
spin_unlock(s);
spin_lock(s);
r1 = READ_ONCE(*x);
}
exists (1:r0=1 /\ 1:r1=0)
[1] https://marc.info/?l=linux-kernel&m=151930201102853&w=2https://groups.google.com/a/groups.riscv.org/forum/#!topic/isa-dev/hKywNHBkAXMhttps://marc.info/?l=linux-kernel&m=151633436614259&w=2
Signed-off-by: Andrea Parri <parri.andrea@gmail.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <albert@sifive.com>
Cc: Daniel Lustig <dlustig@nvidia.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jade Alglave <j.alglave@ucl.ac.uk>
Cc: Luc Maranget <luc.maranget@inria.fr>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Akira Yokosawa <akiyks@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-riscv@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Introduce __smp_{store_release,load_acquire}, and rely on the generic
definitions for smp_{store_release,load_acquire}. This avoids the use
of full ("rw,rw") fences on SMP.
Signed-off-by: Andrea Parri <parri.andrea@gmail.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
We now have dynamic ftrace with the following added items:
* ftrace_make_call, ftrace_make_nop (in kernel/ftrace.c)
The two functions turn each recorded call site of filtered functions
into a call to ftrace_caller or nops
* ftracce_update_ftrace_func (in kernel/ftrace.c)
turns the nops at ftrace_call into a call to a generic entry for
function tracers.
* ftrace_caller (in kernel/mcount-dyn.S)
The entry where each _mcount call sites calls to once they are
filtered to be traced.
Also, this patch fixes the semantic problems in mcount.S, which will be
treated as only a reference implementation once we have the dynamic
ftrace.
Cc: Greentime Hu <greentime@andestech.com>
Signed-off-by: Alan Kao <alankao@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Introduce __smp_{mb,rmb,wmb}, and rely on the generic definitions
for smp_{mb,rmb,wmb}. A first consequence is that smp_{mb,rmb,wmb}
map to a compiler barrier on !SMP (while their definition remains
unchanged on SMP). As a further consequence, smp_load_acquire and
smp_store_release have "fence rw,rw" instead of "fence iorw,iorw".
Signed-off-by: Andrea Parri <parri.andrea@gmail.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
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
Pull clk updates from Stephen Boyd:
"The core framework has a handful of patches this time around, mostly
due to the clk rate protection support added by Jerome Brunet.
This feature will allow consumers to lock in a certain rate on the
output of a clk so that things like audio playback don't hear pops
when the clk frequency changes due to shared parent clks changing
rates. Currently the clk API doesn't guarantee the rate of a clk stays
at the rate you request after clk_set_rate() is called, so this new
API will allow drivers to express that requirement.
Beyond this, the core got some debugfs pretty printing patches and a
couple minor non-critical fixes.
Looking outside of the core framework diff we have some new driver
additions and the removal of a legacy TI clk driver. Both of these hit
high in the dirstat. Also, the removal of the asm-generic/clkdev.h
file causes small one-liners in all the architecture Kbuild files.
Overall, the driver diff seems to be the normal stuff that comes all
the time to fix little problems here and there and to support new
hardware.
Summary:
Core:
- Clk rate protection
- Symbolic clk flags in debugfs output
- Clk registration enabled clks while doing bookkeeping updates
New Drivers:
- Spreadtrum SC9860
- HiSilicon hi3660 stub
- Qualcomm A53 PLL, SPMI clkdiv, and MSM8916 APCS
- Amlogic Meson-AXG
- ASPEED BMC
Removed Drivers:
- TI OMAP 3xxx legacy clk (non-DT) support
- asm*/clkdev.h got removed (not really a driver)
Updates:
- Renesas FDP1-0 module clock on R-Car M3-W
- Renesas LVDS module clock on R-Car V3M
- Misc fixes to pr_err() prints
- Qualcomm MSM8916 audio fixes
- Qualcomm IPQ8074 rounded out support for more peripherals
- Qualcomm Alpha PLL variants
- Divider code was using container_of() on bad pointers
- Allwinner DE2 clks on H3
- Amlogic minor data fixes and dropping of CLK_IGNORE_UNUSED
- Mediatek clk driver compile test support
- AT91 PMC clk suspend/resume restoration support
- PLL issues fixed on si5351
- Broadcom IProc PLL calculation updates
- DVFS support for Armada mvebu CPU clks
- Allwinner fixed post-divider support
- TI clkctrl fixes and support for newer SoCs"
* tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (125 commits)
clk: aspeed: Handle inverse polarity of USB port 1 clock gate
clk: aspeed: Fix return value check in aspeed_cc_init()
clk: aspeed: Add reset controller
clk: aspeed: Register gated clocks
clk: aspeed: Add platform driver and register PLLs
clk: aspeed: Register core clocks
clk: Add clock driver for ASPEED BMC SoCs
clk: mediatek: adjust dependency of reset.c to avoid unexpectedly being built
clk: fix reentrancy of clk_enable() on UP systems
clk: meson-axg: fix potential NULL dereference in axg_clkc_probe()
clk: Simplify debugfs registration
clk: Fix debugfs_create_*() usage
clk: Show symbolic clock flags in debugfs
clk: renesas: r8a7796: Add FDP clock
clk: Move __clk_{get,put}() into private clk.h API
clk: sunxi: Use CLK_IS_CRITICAL flag for critical clks
clk: Improve flags doc for of_clk_detect_critical()
arch: Remove clkdev.h asm-generic from Kbuild
clk: sunxi-ng: a83t: Add M divider to TCON1 clock
clk: Prepare to remove asm-generic/clkdev.h
...
Pull dma mapping updates from Christoph Hellwig:
"Except for a runtime warning fix from Christian this is all about
consolidation of the generic no-IOMMU code, a well as the glue code
for swiotlb.
All the code is based on the x86 implementation with hooks to allow
all architectures that aren't cache coherent to use it.
The x86 conversion itself has been deferred because the x86
maintainers were a little busy in the last months"
* tag 'dma-mapping-4.16' of git://git.infradead.org/users/hch/dma-mapping: (57 commits)
MAINTAINERS: add the iommu list for swiotlb and xen-swiotlb
arm64: use swiotlb_alloc and swiotlb_free
arm64: replace ZONE_DMA with ZONE_DMA32
mips: use swiotlb_{alloc,free}
mips/netlogic: remove swiotlb support
tile: use generic swiotlb_ops
tile: replace ZONE_DMA with ZONE_DMA32
unicore32: use generic swiotlb_ops
ia64: remove an ifdef around the content of pci-dma.c
ia64: clean up swiotlb support
ia64: use generic swiotlb_ops
ia64: replace ZONE_DMA with ZONE_DMA32
swiotlb: remove various exports
swiotlb: refactor coherent buffer allocation
swiotlb: refactor coherent buffer freeing
swiotlb: wire up ->dma_supported in swiotlb_dma_ops
swiotlb: add common swiotlb_map_ops
swiotlb: rename swiotlb_free to swiotlb_exit
x86: rename swiotlb_dma_ops
powerpc: rename swiotlb_dma_ops
...
satp is the name used by the current privileged spec 1.10, use it
instead of the old name. The most recent release binutils release
(2.29) doesn't know about the satp name yet, so stick to the name from
the previous privileged ISA release and comment on the fact.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
RISC-V systems perform TLB shootdows via the SBI, which currently
performs an IPI to each of the remote harts which then performs a local
TLB flush. This process is a bit on the slow side, but we can at least
speed it up for some common cases by restricting the set of harts to
shoot down to the actual set of harts that are currently participating
in the given mm context, as opposed to the entire system.
This should provide a measurable performance increase, but we haven't
measured it. Regardless, it seems like obviously the right thing to do
here.
Signed-off-by: Andrew Waterman <andrew@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
The __ARCH_HAVE_MMU define is (and was) used nowhere in the tree and
also doesn't appear to be used by any libc.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
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>
Pull init_task initializer cleanups from David Howells:
"It doesn't seem useful to have the init_task in a header file rather
than in a normal source file. We could consolidate init_task handling
instead and expand out various macros.
Here's a series of patches that consolidate init_task handling:
(1) Make THREAD_SIZE available to vmlinux.lds for cris, hexagon and
openrisc.
(2) Alter the INIT_TASK_DATA linker script macro to set
init_thread_union and init_stack rather than defining these in C.
Insert init_task and init_thread_into into the init_stack area in
the linker script as appropriate to the configuration, with
different section markers so that they end up correctly ordered.
We can then get merge ia64's init_task.c into the main one.
We then have a bunch of single-use INIT_*() macros that seem only
to be macros because they used to be used per-arch. We can then
expand these in place of the user and get rid of a few lines and
a lot of backslashes.
(3) Expand INIT_TASK() in place.
(4) Expand in place various small INIT_*() macros that are defined
conditionally. Expand them and surround them by #if[n]def/#endif
in the .c file as it takes fewer lines.
(5) Expand INIT_SIGNALS() and INIT_SIGHAND() in place.
(6) Expand INIT_STRUCT_PID in place.
These macros can then be discarded"
* tag 'init_task-20180117' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
Expand INIT_STRUCT_PID and remove
Expand the INIT_SIGNALS and INIT_SIGHAND macros and remove
Expand various INIT_* macros and remove
Expand INIT_TASK() in init/init_task.c and remove
Construct init thread stack in the linker script rather than by union
openrisc: Make THREAD_SIZE available to vmlinux.lds
hexagon: Make THREAD_SIZE available to vmlinux.lds
cris: Make THREAD_SIZE available to vmlinux.lds
For architectures that just use the generic dma_noop_ops we can provide
a generic version of dma-mapping.h.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Construct the init thread stack in the linker script rather than doing it
by means of a union so that ia64's init_task.c can be got rid of.
The following symbols are then made available from INIT_TASK_DATA() linker
script macro:
init_thread_union
init_stack
INIT_TASK_DATA() also expands the region to THREAD_SIZE to accommodate the
size of the init stack. init_thread_union is given its own section so that
it can be placed into the stack space in the right order. I'm assuming
that the ia64 ordering is correct and that the task_struct is first and the
thread_info second.
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Tested-by: Will Deacon <will.deacon@arm.com> (arm64)
Tested-by: Palmer Dabbelt <palmer@sifive.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
The RISC-V port doesn't suport a nommu mode, so there is no reason
to provide some code only under a CONFIG_MMU ifdef.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
We were hoping to avoid making this visible to userspace, but it looks
like we're going to have to because QEMU's user-mode emulation doesn't
want to emulate a vDSO. Having vDSO-only system calls was a bit
unothodox anyway, so I think in this case it's OK to just make the
actual system call number public.
This patch simply moves the definition of __NR_riscv_flush_icache
availiable to userspace, which results in the deletion of the now empty
vdso-syscalls.h.
Changes since v1:
* I've moved the definition into uapi/asm/syscalls.h rathen than
uapi/asm/unistd.h. This allows me to keep asm/unistd.h, so we can
keep the syscall table macros sane.
* As a side effect of the above, this no longer disables all system
calls on RISC-V. Whoops!
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
I removed this last week because of an incorrect comment:
smp_mb__after_spinlock() is actually still used, and is necessary on
RISC-V. It's been resurrected, with a comment that describes what it
actually does this time. Thanks to Andrea for finding the bug!
Fixes: 3343eb6806 ("RISC-V: Remove smb_mb__{before,after}_spinlock()")
CC: Andrea Parri <parri.andrea@gmail.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Olaf said: Here's a short series of patches that produces a working
allmodconfig. Would be nice to see them go in so we can add build
coverage.
I've dropped patches 8 and 10 from the original set:
* [PATCH 08/10] (RISC-V: Set __ARCH_WANT_RENAMEAT to pick up generic
version) has a better fix that I've sent out for review, we don't want
renameat.
* [PATCH 10/10] (input: joystick: riscv has get_cycles) has already been
taken into Dmitry Torokhov's tree.
This merge contains the user-visible, ABI-breaking changes that we want
to make sure we have in Linux before our first release. Highlights
include:
* VDSO entries for clock_get/gettimeofday/getcpu have been added. These
are simple syscalls now, but we want to let glibc use them from the
start so we can make them faster later.
* A VDSO entry for instruction cache flushing has been added so
userspace can flush the instruction cache.
* The VDSO symbol versions for __vdso_cmpxchg{32,64} have been removed,
as those VDSO entries don't actually exist.
Conflicts:
arch/riscv/include/asm/tlbflush.h
Whoops -- I must have just been being an idiot again. Thanks to Segher
for finding the bug :).
CC: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Despite RISC-V having a direct 'fence.i' instruction available to
userspace (which we can't trap!), that's not actually viable when
running on Linux because the kernel might schedule a process on another
hart. There is no way for userspace to handle this without invoking the
kernel (as it doesn't know the thread->hart mappings), so we've defined
a RISC-V specific system call to flush the instruction cache.
This patch adds both a system call and a VDSO entry. If possible, we'd
like to avoid having the system call be considered part of the
user-facing ABI and instead restrict that to the VDSO entry -- both just
in general to avoid having additional user-visible ABI to maintain, and
because we'd prefer that users just call the VDSO entry because there
might be a better way to do this in the future (ie, one that doesn't
require entering the kernel).
Signed-off-by: Andrew Waterman <andrew@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
The RISC-V ISA allows for instruction caches that are not coherent WRT
stores, even on a single hart. As a result, we need to explicitly flush
the instruction cache whenever marking a dirty page as executable in
order to preserve the correct system behavior.
Local instruction caches aren't that scary (our implementations actually
flush the cache, but RISC-V is defined to allow higher-performance
implementations to exist), but RISC-V defines no way to perform an
instruction cache shootdown. When explicitly asked to do so we can
shoot down remote instruction caches via an IPI, but this is a bit on
the slow side.
Instead of requiring an IPI to all harts whenever marking a page as
executable, we simply flush the currently running harts. In order to
maintain correct behavior, we additionally mark every other hart as
needing a deferred instruction cache which will be taken before anything
runs on it.
Signed-off-by: Andrew Waterman <andrew@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Fixes:
include/asm-generic/mm_hooks.h:20:11: warning: 'struct vm_area_struct' declared inside parameter list will not be visible outside of this definition or declaration
include/asm-generic/mm_hooks.h:19:38: warning: 'struct mm_struct' declared inside parameter list will not be visible outside of this definition or declaration
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
include <linux/types.h> for __iomem definition. Also, add volatile to
iounmap() like other architectures have it to avoid "discarding
volatile" warnings from some drivers.
Finally, explicitly promote the base address for INB/OUTB functions to
avoid some old legacy drivers complaining about int-to-ptr promotions.
The drivers are unlikely to work but they're included in allmodconfig
so the warnings are noisy.
Fixes, among other warnings, these with allmodconfig:
../arch/riscv/include/asm/io.h:24:21: error: expected '=', ',', ';', 'asm' or '__attribute__' before '*' token
extern void __iomem *ioremap(phys_addr_t offset, unsigned long size);
sound/pci/echoaudio/echoaudio.c: In function 'snd_echo_free':
sound/pci/echoaudio/echoaudio.c:1879:10: warning: passing argument 1 of 'iounmap' discards 'volatile' qualifier from pointer target type [-Wdiscarded-qualifiers]
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
INT and SHORT are used by some drivers that pull in the include files,
so prefixing helps avoid namespace conflicts. Other constructs in the
same file already uses this.
Fixes, among others, these warnings with allmodconfig:
../sound/core/pcm_misc.c:43:0: warning: "INT" redefined
#define INT __force int
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Fixes this from allmodconfig:
drivers/tty/serial/earlycon.c:27:10: fatal error: asm/serial.h: No such file or directory
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This was removed from the other architectures in commit
952111d7db ("arch: Remove spin_unlock_wait() arch-specific
definitions"). That landed between when we got upstream and when our
patches were reviewed, so this is a followup patch.
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This is just a comment change, but it's one that bit me on the mailing
list. It turns out that issuing a `sfence.vma` enforces instruction
cache ordering in addition to TLB ordering. This isn't explicitly
called out in the ISA manual, but Andrew will be making that more clear
in a future revision.
CC: Andrew Waterman <andrew@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
I mis-read the documentation. After looking at it again the
documentation is actually as clear as it can be, it's just that I didn't
actually read it in order and therefor did the wrong thing.
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Our atomics are generated from a complicated series of preprocessor
macros, each of which is slightly different from the last. When writing
the macros I'd accidentally left some unused arguments floating around.
This patch removes the unused macro arguments.
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Pull RISC-V architecture support from Palmer Dabbelt:
"This contains the core RISC-V Linux port, which has been through nine
rounds of review on various mailing lists. The port is not complete:
there's some cleanup patches moving through the review process, a
whole bunch of drivers that need some work, and a lot of feature
additions that will be needed.
The patches contained in this tag have been through nine rounds of
review on the various mailing lists. I have some outstanding cleanup
patches, but since there's been so much review on these patches I
thought it would be best to submit them as-is and then submit explicit
cleanup patches so everyone can review them. This first patch set is
big enough that it's a bit of a pain to constantly rewrite, and it's
caused a few headaches with various contributors.
The port is definately a work in progress. While what's there builds
and boots with 4.14, it's a bit hard to actually see anything happen
because there are no device drivers yet. I maintain a staging branch
that contains all the device drivers and cleanup that actually works,
but those patches won't all be ready for a while. I'd like to get what
we currently have into your tree so everyone can start working from a
single base -- of particular importance is allowing the glibc
upstreaming process to proceed so we can sort out any possibly
lingering user-visible ABI problems we might have.
Copied below is the ChangeLog that contains the history of this patch
set:
(v9) As per suggestions on our v8 patch set, I've split the core
architecture code out from our drivers and would like to submit
this patch set to be included into linux-next, with the goal
being to be merged in during the next merge window. This patch
set is based on 4.14-rc2, but if it's better to have it based on
something else then I can change it around.
This patch set contains just the core arch code for RISC-V, so
while it builds an nominally boots, you can't print or take an
interrupt so it's not that useful. If you're looking to actually
boot a system it would probably be better to use the full patch
set listed below.
We've collected a handful of tags from reviewers, and the
remainder of the patch set only got minimal feedback last time.
Here's what changed:
- We now use the device tree to initialize the timer driver so
it's less tighly coupled with the arch port.
- I cleaned up the defconfigs -- there's actually now just one,
and it's empty. For now I think we're OK with what the kernel
sets as defaults, but I anticipate we'll begin to expand this
as people start to use the port more.
- The VDSO symbols version is sane.
- We WFI while spinning in the boot loop.
- A handful of comments have been added.
While there are still a handful of FIXMEs in this patch set,
we've started to get enough interest from various users and
contributors that maintaining an out of tree patch set is
starting to become a big burden. Hopefully the patches are good
enough to merge now, which will at least get everyone working in
a more reasonable manner as we clean up the remaining issues.
(v8) I know it may not be the ideal time to submit a patch set right
now, as it's the middle of the merge window, but things have
calmed down quite a bit in the last month so I thought it would
be good to get everyone on the same page. There's been a handful
of changes since the last patch set, but most of them are fairly
minor:
- We changed PAGE_OFFSET to allowing mapping more physical
memory on 64-bit systems. This is user configurable, as it
triggers a different code model that generates slightly less
efficient code.
- The device tree binding documentation is back, I'd managed to
lose it at some point.
- We now pass the atomic64 test suite
- The SBI timer driver has been refactored.
(v7) It's been a while since my last patch set, but the changes han
been fairly minimal:
- The PCI cleanup patches have been dropped, we'll do them as a
separate patch set later.
- We've the Kconfig entries from CONFIG_ISA_* to
CONFIG_RISCV_ISA_*, to make grep easier.
- There have been a handful of memory model related tweaks in
I/O land, particularly relating the PCI and the upcoming
platform specification. There are significant comments in the
relevant files. This is still a WIP, but I think we're close
to getting as good as we're going to get until we end up with
some more specifications.
(v6) As it's been only a day since the v5 patch set, the changes are
pretty minimal:
- The patch set is now based on linux-next/master, which I
believe is a better base now that we're getting closer to
upstream.
- EARLY_PRINTK is no longer an option. Since the SBI console is
reasonable, there's no penalty to enabling it (and thus no
benefit to disabling it).
- The mmap syscalls were refactored a bit.
(v5) Things have really started to calm down, so this is fairly
similar to the v4 patch set. The most interesting changes
include:
- We've moved back to a single patch set.
- SMP support has been fixed, I was accidentally running on a
non-SMP configuration. There were various mistakes all over
the tree as a result of this.
- The cmpxchg syscalls have been removed, as they were deemed a
bad idea. As a result, RISC-V Linux systems mandate the A
extension. The corresponding Kconfig entry to enable builds
on non-A systems has been removed.
- A few more atomic fixes: mostly fence changes, but those
resulted in a handful of additional macros that were no
longer necessary.
- riscv_early_sie has been removed.
(v4) There have only been a few changes since the v3 patch set:
- The cmpxchg64 syscall is no longer enabled on 32-bit systems.
It's not possible to provide this on SMP systems, and it's
not necessary as glibc knows not to call it.
- We provide a ELF_HWCAP so users can determine the ISA of the
machine the kernel is running on.
- The multi-line comments are in a better form.
- There were a handful of headers that could be replaced with
the asm-generic versions, and a few unnecessary definitions.
- We no longer use printk, but instead use pr_*.
- A few Kconfig and defconfig entries have been cleaned up.
(v3) A highlight of the changes since the v2 patch set includes:
- We've split out all our drivers into separate patch sets,
which I've already sent out to the relevant maintainers. I
haven't included those patches in this patch set, but some of
them are necessary to build our port.
- The patch set is now split up differently: rather than being
split per directory it is split per topic. Hopefully this
will make it easier to review the port on the mailing list.
The split is a bit rough, so you probably still want to look
at the patch set as a whole.
- atomic.h has been completely rewritten and is hopefully now
correct. I've attempted to sanitize the various other memory
model related code as well, and I think it should all be sane
now aside from a handful of FIXMEs commented in the code.
- We've changed the cmpexchg syscall to always exist and to not
be multiplexed. There is also a VDSO entry for compare and
exchange, which allows kernels with the A extension to
execute user code without the A extension reasonably fast.
- Our user-visible register state now contains enough space for
the Q extension for 128-bit floating point, as well as a few
words to allow extensibility to future ISA extensions like
the eventual V extension for vectors.
- A handful of driver cleanups, but these have been split into
separate patch sets now so I won't duplicate them here.
(v2) A highlight of the changes since the v1 patch set includes:
- We've split out our drivers into the right places, which
means now there's a lot more patches. I'll be submitting
these patches to various subsystem maintainers and including
them in any future RISC-V patch sets until they've been
merged.
- The SBI console driver has been completely rewritten to use
the HVC helpers and is now significantly smaller.
- We've begun to use weaker barriers as opposed to just the big
"fence". There's still some work to do here, specifically:
- We need fences in the relaxed MMIO functions.
- The non-relaxed MMIO functions are missing R/W bits on their fences.
- Many AMOs need the aq and rl bits set.
- We now have thread_info in task_struct. As a result, sscratch
now contains TP instead of SP. This was necessary because
thread_info is no longer on the stack.
- A few shared routines have been added that we use instead of
creating another arch copy"
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
* tag 'riscv-for-linus-4.15-arch-v9-premerge' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/linux:
RISC-V: Build Infrastructure
RISC-V: User-facing API
RISC-V: Paging and MMU
RISC-V: Device, timer, IRQs, and the SBI
RISC-V: Task implementation
RISC-V: ELF and module implementation
RISC-V: Generic library routines and assembly
RISC-V: Atomic and Locking Code
RISC-V: Init and Halt Code
dt-bindings: RISC-V CPU Bindings
lib: Add shared copies of some GCC library routines
MAINTAINERS: Add RISC-V
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>
This patch contains code that is in some way visible to the user:
including via system calls, the VDSO, module loading and signal
handling. It also contains some generic code that is ABI visible.
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
This patch contains code to manage the RISC-V MMU, including definitions
of the page tables and the page walking code.
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
