RISC-V: Move to queued RW locks

Now that we have fair spinlocks we can use the generic queued rwlocks,
so we might as well do so.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Palmer Da

RISC-V: Move to queued RW locks

Now that we have fair spinlocks we can use the generic queued rwlocks,
so we might as well do so.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

show more ...

RISC-V: Move to generic spinlocks

Our existing spinlocks aren't fair and replacing them has been on the
TODO list for a long time. This moves to the recently-introduced ticket
spinlocks, which are

RISC-V: Move to generic spinlocks

Our existing spinlocks aren't fair and replacing them has been on the
TODO list for a long time. This moves to the recently-introduced ticket
spinlocks, which are simple enough that they are likely to be correct
and fast on the vast majority of extant implementations.

This introduces a horrible hack that allows us to split out the spinlock
conversion from the rwlock conversion. We have to do the spinlocks
first because qrwlock needs fair spinlocks, but we don't want to pollute
the asm-generic code to support the generic spinlocks without qrwlocks.
Thus we pollute the RISC-V code, but just until the next commit as it's
all going away.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Guo Ren <guoren@kernel.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

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parport_pc: Also enable driver for PCI systems

Nowadays PC-style parallel ports come in the form of PCI and PCIe option
cards and there are some combined parallel/serial option cards as well
that we

parport_pc: Also enable driver for PCI systems

Nowadays PC-style parallel ports come in the form of PCI and PCIe option
cards and there are some combined parallel/serial option cards as well
that we handle in the parport subsystem. There is nothing in particular
that would prevent them from being used in any system equipped with PCI
or PCIe connectivity, except that we do not permit the PARPORT_PC config
option to be selected for platforms for which ARCH_MIGHT_HAVE_PC_PARPORT
has not been set for.

The only PCI platforms that actually can't make use of PC-style parallel
port hardware are those newer PCIe systems that have no support for I/O
cycles in the host bridge, required by such parallel ports. Notably,
this includes the s390 arch, which has port I/O accessors that cause
compilation warnings (promoted to errors with `-Werror'), and there are
other cases such as the POWER9 PHB4 device, though this one has variable
port I/O accessors that depend on the particular system. Also it is not
clear whether the serial port side of devices enabled by PARPORT_SERIAL
uses port I/O or MMIO. Finally Super I/O solutions are always either
ISA or platform devices.

Make the PARPORT_PC option selectable also for PCI systems then, except
for the s390 arch, however limit the availability of PARPORT_PC_SUPERIO
to platforms that enable ARCH_MIGHT_HAVE_PC_PARPORT. Update platforms
accordingly for the required <asm/parport.h> header.

Acked-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2202141955550.34636@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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riscv: switch to relative exception tables

Similar as other architectures such as arm64, x86 and so on, use
offsets relative to the exception table entry values rather than
absolute addresses for bo

riscv: switch to relative exception tables

Similar as other architectures such as arm64, x86 and so on, use
offsets relative to the exception table entry values rather than
absolute addresses for both the exception locationand the fixup.

However, RISCV label difference will actually produce two relocations,
a pair of R_RISCV_ADD32 and R_RISCV_SUB32. Take below simple code for
example:

$ cat test.S
.section .text
1:
nop
.section __ex_table,"a"
.balign 4
.long (1b - .)
.previous

$ riscv64-linux-gnu-gcc -c test.S
$ riscv64-linux-gnu-readelf -r test.o
Relocation section '.rela__ex_table' at offset 0x100 contains 2 entries:
Offset Info Type Sym. Value Sym. Name + Addend
000000000000 000600000023 R_RISCV_ADD32 0000000000000000 .L1^B1 + 0
000000000000 000500000027 R_RISCV_SUB32 0000000000000000 .L0 + 0

The modpost will complain the R_RISCV_SUB32 relocation, so we need to
patch modpost.c to skip this relocation for .rela__ex_table section.

After this patch, the __ex_table section size of defconfig vmlinux is
reduced from 7072 Bytes to 3536 Bytes.

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

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local64.h: make <asm/local64.h> mandatory

Make <asm-generic/local64.h> mandatory in include/asm-generic/Kbuild and
remove all arch/*/include/asm/local64.h arch-specific files since they
only #includ

local64.h: make <asm/local64.h> mandatory

Make <asm-generic/local64.h> mandatory in include/asm-generic/Kbuild and
remove all arch/*/include/asm/local64.h arch-specific files since they
only #include <asm-generic/local64.h>.

This fixes build errors on arch/c6x/ and arch/nios2/ for
block/blk-iocost.c.

Build-tested on 21 of 25 arch-es. (tools problems on the others)

Yes, we could even rename <asm-generic/local64.h> to
<linux/local64.h> and change all #includes to use
<linux/local64.h> instead.

Link: https://lkml.kernel.org/r/20201227024446.17018-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <jacquiot.aurelien@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

local64.h: make <asm/local64.h> mandatory

[ Upstream commit 87dbc209ea04645fd2351981f09eff5d23f8e2e9 ]

Make <asm-generic/local64.h> mandatory in include/asm-generic/Kbuild and
remove all arch/*/inc

local64.h: make <asm/local64.h> mandatory

[ Upstream commit 87dbc209ea04645fd2351981f09eff5d23f8e2e9 ]

Make <asm-generic/local64.h> mandatory in include/asm-generic/Kbuild and
remove all arch/*/include/asm/local64.h arch-specific files since they
only #include <asm-generic/local64.h>.

This fixes build errors on arch/c6x/ and arch/nios2/ for
block/blk-iocost.c.

Build-tested on 21 of 25 arch-es. (tools problems on the others)

Yes, we could even rename <asm-generic/local64.h> to
<linux/local64.h> and change all #includes to use
<linux/local64.h> instead.

Link: https://lkml.kernel.org/r/20201227024446.17018-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <jacquiot.aurelien@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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RISC-V: Add early ioremap support

UEFI uses early IO or memory mappings for runtime services before
normal ioremap() is usable. Add the necessary fixmap bindings and
pmd mappings for generic ioremap

RISC-V: Add early ioremap support

UEFI uses early IO or memory mappings for runtime services before
normal ioremap() is usable. Add the necessary fixmap bindings and
pmd mappings for generic ioremap support to work.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

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asm-generic: make more kernel-space headers mandatory

Change a header to mandatory-y if both of the following are met:

[1] At least one architecture (except um) specifies it as generic-y in
arc

asm-generic: make more kernel-space headers mandatory

Change a header to mandatory-y if both of the following are met:

[1] At least one architecture (except um) specifies it as generic-y in
arch/*/include/asm/Kbuild

[2] Every architecture (except um) either has its own implementation
(arch/*/include/asm/*.h) or specifies it as generic-y in
arch/*/include/asm/Kbuild

This commit was generated by the following shell script.

----------------------------------->8-----------------------------------

arches=$(cd arch; ls -1 | sed -e '/Kconfig/d' -e '/um/d')

tmpfile=$(mktemp)

grep "^mandatory-y +=" include/asm-generic/Kbuild > $tmpfile

find arch -path 'arch/*/include/asm/Kbuild' |
xargs sed -n 's/^generic-y += \(.*\)/\1/p' | sort -u |
while read header
do
mandatory=yes

for arch in $arches
do
if ! grep -q "generic-y += $header" arch/$arch/include/asm/Kbuild &&
! [ -f arch/$arch/include/asm/$header ]; then
mandatory=no
break
fi
done

if [ "$mandatory" = yes ]; then
echo "mandatory-y += $header" >> $tmpfile

for arch in $arches
do
sed -i "/generic-y += $header/d" arch/$arch/include/asm/Kbuild
done
fi

done

sed -i '/^mandatory-y +=/d' include/asm-generic/Kbuild

LANG=C sort $tmpfile >> include/asm-generic/Kbuild

----------------------------------->8-----------------------------------

One obvious benefit is the diff stat:

25 files changed, 52 insertions(+), 557 deletions(-)

It is tedious to list generic-y for each arch that needs it.

So, mandatory-y works like a fallback default (by just wrapping
asm-generic one) when arch does not have a specific header
implementation.

See the following commits:

def3f7cefe4e81c296090e1722a76551142c227c
a1b39bae16a62ce4aae02d958224f19316d98b24

It is tedious to convert headers one by one, so I processed by a shell
script.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: http://lkml.kernel.org/r/20200210175452.5030-1-masahiroy@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

asm-generic: Make dma-contiguous.h a mandatory include/asm header

dma-continuguous.h is generic for all architectures except arm32 which has
its own version.

Similar change was done for msi.h by co

asm-generic: Make dma-contiguous.h a mandatory include/asm header

dma-continuguous.h is generic for all architectures except arm32 which has
its own version.

Similar change was done for msi.h by commit a1b39bae16a6
("asm-generic: Make msi.h a mandatory include/asm header")

Suggested-by: Christoph Hellwig <hch@infradead.org>
Link: https://lore.kernel.org/linux-arm-kernel/20200117080446.GA8980@lst.de/T/#m92bb56b04161057635d4142e1b3b9b6b0a70122e
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Paul Walmsley <paul.walmsley@sifive.com> # for arch/riscv

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asm-generic: Make msi.h a mandatory include/asm header

msi.h is generic for all architectures except x86, which has its own
version. Enabling MSI by adding msi.h to every architecture's Kbuild is
j

asm-generic: Make msi.h a mandatory include/asm header

msi.h is generic for all architectures except x86, which has its own
version. Enabling MSI by adding msi.h to every architecture's Kbuild is
just an additional step which doesn't need to be done.

Make msi.h mandatory in the asm-generic/Kbuild so we don't have to do it
for each architecture.

Suggested-by: Christoph Hellwig <hch@infradead.org>
Link: https://lore.kernel.org/r/c991669e29a79b1a8e28c3b4b3a125801a693de8.1571983829.git.michal.simek@xilinx.com
Tested-by: Paul Walmsley <paul.walmsley@sifive.com> # build only, rv32/rv64
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Waiman Long <longman@redhat.com>
Acked-by: Paul Walmsley <paul.walmsley@sifive.com> # arch/riscv

show more ...

riscv: include generic support for MSI irqdomains

Some RISC-V systems include PCIe host controllers that support PCIe
message-signaled interrupts. For this to work on Linux, we need to
enable PCI_M

riscv: include generic support for MSI irqdomains

Some RISC-V systems include PCIe host controllers that support PCIe
message-signaled interrupts. For this to work on Linux, we need to
enable PCI_MSI_IRQ_DOMAIN and define struct msi_alloc_info. Support
for the latter is enabled by including the architecture-generic msi.h
include.

Signed-off-by: Wesley Terpstra <wesley@sifive.com>
[paul.walmsley@sifive.com: split initial patch into one arch/riscv
patch and one drivers/pci patch]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>

show more ...

riscv: add binfmt_flat support

Just use the generic definitions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>

treewide: Add SPDX license identifier - Kbuild

Add SPDX license identifiers to all Make/Kconfig files which:

- Have no license information of any form

These files fall under the project license,

treewide: Add SPDX license identifier - Kbuild

Add SPDX license identifiers to all Make/Kconfig files which:

- Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0

Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

arch: remove dangling asm-generic wrappers

These generic-y defines do not have the corresponding generic header
in include/asm-generic/, so they are definitely invalid.

Signed-off-by: Masahiro Yama

arch: remove dangling asm-generic wrappers

These generic-y defines do not have the corresponding generic header
in include/asm-generic/, so they are definitely invalid.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

show more ...

riscv: use asm-generic/extable.h

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

riscv/mmiowb: Hook up mmwiob() implementation to asm-generic code

In a bid to kill off explicit mmiowb() usage in driver code, hook up
the asm-generic mmiowb() tracking code for riscv, so that an mm

riscv/mmiowb: Hook up mmwiob() implementation to asm-generic code

In a bid to kill off explicit mmiowb() usage in driver code, hook up
the asm-generic mmiowb() tracking code for riscv, so that an mmiowb()
is automatically issued from spin_unlock() if an I/O write was performed
in the critical section.

Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

show more ...

arch: Use asm-generic header for asm/mmiowb.h

Hook up asm-generic/mmiowb.h to Kbuild for all architectures so that we
can subsequently include asm/mmiowb.h from core code.

Cc: Masahiro Yamada <yama

arch: Use asm-generic header for asm/mmiowb.h

Hook up asm-generic/mmiowb.h to Kbuild for all architectures so that we
can subsequently include asm/mmiowb.h from core code.

Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>

show more ...

riscv: remove redundant kernel-space generic-y

This commit removes redundant generic-y defines in
arch/riscv/include/asm/Kbuild.

[1] It is redundant to define the same generic-y in both
arch/$(

riscv: remove redundant kernel-space generic-y

This commit removes redundant generic-y defines in
arch/riscv/include/asm/Kbuild.

[1] It is redundant to define the same generic-y in both
arch/$(ARCH)/include/asm/Kbuild and
arch/$(ARCH)/include/uapi/asm/Kbuild.

Remove the following generic-y:

errno.h
fcntl.h
ioctl.h
ioctls.h
ipcbuf.h
mman.h
msgbuf.h
param.h
poll.h
posix_types.h
resource.h
sembuf.h
setup.h
shmbuf.h
signal.h
socket.h
sockios.h
stat.h
statfs.h
swab.h
termbits.h
termios.h
types.h

[2] It is redundant to define generic-y when arch-specific
implementation exists in arch/$(ARCH)/include/asm/*.h

Remove the following generic-y:

cacheflush.h
module.h

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

show more ...

RISC-V: Add futex support.

Here is an attempt to add the missing futex support. I started with the MIPS
version of futex.h and modified it until I got it working. I tested it on
a HiFive Unleashed

RISC-V: Add futex support.

Here is an attempt to add the missing futex support. I started with the MIPS
version of futex.h and modified it until I got it working. I tested it on
a HiFive Unleashed running Fedora Core 29 using the fc29 4.15 version of the
kernel. This was tested against the glibc testsuite, where it fixes 14 nptl
related testsuite failures. That unfortunately only tests the cmpxchg support,
so I also used the testcase at the end of

https://lwn.net/Articles/148830/

which tests the atomic_op functionality, except that it doesn't verify that
the operations are atomic, which they obviously are. This testcase runs
successfully with the patch and fails without it.

I'm not a kernel expert, so there could be details I got wrong here. I wasn't
sure about the memory model support, so I used aqrl which seemed safest, and
didn't add fences which seemed unnecessary. I'm not sure about the copyright
statements, I left in Ralf Baechle's line because I started with his code.
Checkpatch reports some style problems, but it is the same style as the MIPS
futex.h, and the uses of ENOSYS appear correct even though it complains about
them. I don't know if any of that matters.

This patch was tested on qemu with the glibc nptl/tst-cond-except
testcase, and the wake_op testcase from above.

Signed-off-by: Jim Wilson <jimw@sifive.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

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riscv: Delete asm/compat.h

riscv does not enable CONFIG_COMPAT in default configurations:
defconfig, allmodconfig and allnoconfig.
Remove the asm/compat.h as it does not seem to add any value to
the

riscv: Delete asm/compat.h

riscv does not enable CONFIG_COMPAT in default configurations:
defconfig, allmodconfig and allnoconfig.
Remove the asm/compat.h as it does not seem to add any value to
the architecture without CONFIG_COMPAT.

Now that time compat syscalls are being reused in non CONFIG_COMPAT
modes, asm-generic/compat.h provides definitions for riscv 32 bit
mode.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: palmer@sifive.com
Cc: linux-riscv@lists.infradead.org
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

show more ...

perf: riscv: preliminary RISC-V support

This patch provide a basic PMU, riscv_base_pmu, which supports two
general hardware event, instructions and cycles. Furthermore, this
PMU serves as a referen

perf: riscv: preliminary RISC-V support

This patch provide a basic PMU, riscv_base_pmu, which supports two
general hardware event, instructions and cycles. Furthermore, this
PMU serves as a reference implementation to ease the portings in
the future.

riscv_base_pmu should be able to run on any RISC-V machine that
conforms to the Priv-Spec. Note that the latest qemu model hasn't
fully support a proper behavior of Priv-Spec 1.10 yet, but work
around should be easy with very small fixes. Please check
https://github.com/riscv/riscv-qemu/pull/115 for future updates.

Cc: Nick Hu <nickhu@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Signed-off-by: Alan Kao <alankao@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

show more ...

riscv: there is no <asm/handle_irq.h>

So don't list it as generic-y.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>

RISC-V: Move to the new GENERIC_IRQ_MULTI_HANDLER handler

The existing mechanism for handling IRQs on RISC-V is pretty ugly: the irq
entry code selects the handler via Kconfig dependencies.

Use the

RISC-V: Move to the new GENERIC_IRQ_MULTI_HANDLER handler

The existing mechanism for handling IRQs on RISC-V is pretty ugly: the irq
entry code selects the handler via Kconfig dependencies.

Use the new generic IRQ handling infastructure, which allows boot time
registration of the low level entry handler.

This does add an additional load to the interrupt latency, but there's a
lot of tuning left to be done there on RISC-V so it's OK for now.

Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Stafford Horne <shorne@gmail.com>
Cc: jonas@southpole.se
Cc: catalin.marinas@arm.com
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux@armlinux.org.uk
Cc: stefan.kristiansson@saunalahti.fi
Cc: openrisc@lists.librecores.org
Cc: linux-riscv@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lkml.kernel.org/r/20180307235731.22627-3-palmer@sifive.com

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riscv/ftrace: Add basic support

This patch contains basic ftrace support for RV64I platform.
Specifically, function tracer (HAVE_FUNCTION_TRACER), function graph
tracer (HAVE_FUNCTION_GRAPH_TRACER),

riscv/ftrace: Add basic support

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>

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dma-mapping: provide a generic asm/dma-mapping.h

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@ls

dma-mapping: provide a generic asm/dma-mapping.h

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>

show more ...