This patchset adds an option, CONFIG_FPU, to enable/disable floating-
point support within the kernel. The kernel's new behavior will be as
follows:
* with CONFIG_FPU=y
All FPU codes are reserved. If no FPU is found during booting, a
global flag will be set, and those functions will be bypassed with
condition check to that flag.
* with CONFIG_FPU=n
No floating-point instructions in kernel and all related settings
are excluded.
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
FPU codes have been separated from common part in previous patches.
This patch add the CONFIG_FPU option and some stubs, so that a no-FPU
configuration is allowed.
Signed-off-by: Alan Kao <alankao@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Cc: Vincent Chen <vincentc@andestech.com>
Cc: Zong Li <zong@andestech.com>
Cc: Nick Hu <nickhu@andestech.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This patch cleanup the MARCH string passing to both compiler and
assembler. Note that the CFLAGS should not contain "fd" before we
have mechnisms like kernel_fpu_begin/end in other architectures.
Signed-off-by: Alan Kao <alankao@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Cc: Vincent Chen <vincentc@andestech.com>
Cc: Zong Li <zong@andestech.com>
Cc: Nick Hu <nickhu@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Commit a0f97e06a4 ("kbuild: enable 'make CFLAGS=...' to add
additional options to CC") renamed CFLAGS to KBUILD_CFLAGS.
Commit 222d394d30 ("kbuild: enable 'make AFLAGS=...' to add
additional options to AS") renamed AFLAGS to KBUILD_AFLAGS.
Commit 06c5040cdb ("kbuild: enable 'make CPPFLAGS=...' to add
additional options to CPP") renamed CPPFLAGS to KBUILD_CPPFLAGS.
For some reason, LDFLAGS was not renamed.
Using a well-known variable like LDFLAGS may result in accidental
override of the variable.
Kbuild generally uses KBUILD_ prefixed variables for the internally
appended options, so here is one more conversion to sanitize the
naming convention.
I did not touch Makefiles under tools/ since the tools build system
is a different world.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
This tag contains some major improvements to the RISC-V port, including
the necessary interrupt controller and timer support to actually make it
to userspace. Support for three devices has been added:
* Support for the ISA-mandated timers on RISC-V systems.
* Support for the ISA-mandated first-level interrupt controller on
RISC-V systems, which is handled as part of our core arch code because
it's very small and tightly tied to the ISA.
* Support for SiFive's platform-level interrupt controller, which talks
to the actual devices.
In addition to these new devices, there are a handful of cleanups all
over the RISC-V tree:
* Build fixes for various configurations
* A fix to the vDSO build's makefile so it respects CFLAGS.
* The addition of __lshrti3, a libgcc derived function necessary for
some 32-bit configurations.
* !SMP && PERF_EVENTS
* Cleanups to the arch code to remove the remnants of old versions of
the drivers that were just properly submitted.
* Some dead code from the timer driver, most of which wasn't ever
even compiled.
* Cleanups of some interrupt #defines, which are now local to the
interrupt handling code.
* Fixes to ptrace(), which while not being sufficient to fully make GDB
work are at least sufficient to get simple GDB tasks to work.
* Early printk support via RISC-V's architecturally mandated SBI console
device.
* A fix to our early debug trap handler to ensure it's always aligned.
These patches have all been through a fairly extensive review process,
but as this enables a whole pile of functionality (ie, userspace) I'm
confident we'll need to submit a few more patches. The only concrete
issues I know about are the sys_riscv_flush_icache patches, but as I
managed to screw those up on Friday I figured it'd be best to let them
bake another week.
This tag boots a Fedora root filesystem on QEMU's master branch for me,
and before this morning's rebase (from 4.18-rc8 to 4.18) it booted on
the HiFive Unleashed.
Thanks to Christoph Hellwig and the other guys at WD for getting the new
drivers in shape!
-----BEGIN PGP SIGNATURE-----
iQJHBAABCAAxFiEEAM520YNJYN/OiG3470yhUCzLq0EFAltx3HcTHHBhbG1lckBk
YWJiZWx0LmNvbQAKCRDvTKFQLMurQc7nEACh8NCRLyXHOAQefomb+BUx+DJXweau
lhTiPexB7+3ZAT6FvL8BgHFu3qMsgZ8iI5pxIz7tap2WRTlakRABLes7c3xQPI4a
3rDbZFE78lQDNY0Kj8iUpvYr0aOfMcC8aoD30qQHaWZVgYZvaZGD3Sar6VbTyaNe
5F5lRaiAtrMmHNio/fXQvnMP83nc1Nxzc4q8VeRjmufc0CvGZUs3L2ZRVx1phwav
VedQFsrNHlcyulBv9rQXzaeyvVn+FNKlu4c/9sI6xsGZofGZjOqub1vjURuEfTc5
4AtdFMN0Xb2TYCK277Fr/FY/VEHGXCV+3hGc2U62hnpBtRgGERn7gQUimCJD5b+V
gpXZGjtLvTXp9a4N6+ThC/oqvr72aLzInNap95MFK5xSMx/4AdCG7u63sd2qLtkL
tlYho+Hd50ImIlUCTs6pfjzmgTMLW2huVJhDNx2lt9OUvNNYjTc4mjEK2WK8DUC7
aUMcHYZMn3hJFNwvd5xTxLPua4ahhhYTyfzHwnMiND4ZjdUnxtrKNj46HjSPqMp9
mgKOkv3G0a021gYODI/dweYI1SV2my814fQHZW4rcFYM2lLwrn2cPMMGezAJF9sR
mbLHW6ZxJrtd9m+RZsJB9Z3QnBs68yIqTOBPRRFM5egwt9s9y+19HnBDVe1hj8/j
OpmZ/qXCqQt+jA==
=PfnC
-----END PGP SIGNATURE-----
Merge tag 'riscv-for-linus-4.19-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux
Pull RISC-V updates from Palmer Dabbelt:
"This contains some major improvements to the RISC-V port, including
the necessary interrupt controller and timer support to actually make
it to userspace. Support for three devices has been added:
- the ISA-mandated timers on RISC-V systems.
- the ISA-mandated first-level interrupt controller on RISC-V
systems, which is handled as part of our core arch code because
it's very small and tightly tied to the ISA.
- SiFive's platform-level interrupt controller, which talks to the
actual devices.
In addition to these new devices, there are a handful of cleanups all
over the RISC-V tree:
- build fixes for various configurations:
* A fix to the vDSO build's makefile so it respects CFLAGS.
* The addition of __lshrti3, a libgcc derived function necessary
for some 32-bit configurations.
* !SMP && PERF_EVENTS
- Cleanups to the arch code to remove the remnants of old versions of
the drivers that were just properly submitted.
* Some dead code from the timer driver, most of which wasn't ever
even compiled.
* Cleanups of some interrupt #defines, which are now local to the
interrupt handling code.
- Fixes to ptrace(), which while not being sufficient to fully make
GDB work are at least sufficient to get simple GDB tasks to work.
- Early printk support via RISC-V's architecturally mandated SBI
console device.
- A fix to our early debug trap handler to ensure it's always
aligned.
These patches have all been through a fairly extensive review process,
but as this enables a whole pile of functionality (ie, userspace) I'm
confident we'll need to submit a few more patches. The only concrete
issues I know about are the sys_riscv_flush_icache patches, but as I
managed to screw those up on Friday I figured it'd be best to let them
bake another week.
This tag boots a Fedora root filesystem on QEMU's master branch for
me, and before this morning's rebase (from 4.18-rc8 to 4.18) it booted
on the HiFive Unleashed.
Thanks to Christoph Hellwig and the other guys at WD for getting the
new drivers in shape!"
* tag 'riscv-for-linus-4.19-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux:
dt-bindings: interrupt-controller: SiFive Plaform Level Interrupt Controller
dt-bindings: interrupt-controller: RISC-V local interrupt controller
RISC-V: Fix !CONFIG_SMP compilation error
irqchip: add a SiFive PLIC driver
RISC-V: Add the directive for alignment of stvec's value
clocksource: new RISC-V SBI timer driver
RISC-V: implement low-level interrupt handling
RISC-V: add a definition for the SIE SEIE bit
RISC-V: remove INTERRUPT_CAUSE_* defines from asm/irq.h
RISC-V: simplify software interrupt / IPI code
RISC-V: remove timer leftovers
RISC-V: Add early printk support via the SBI console
RISC-V: Don't increment sepc after breakpoint.
RISC-V: implement __lshrti3.
RISC-V: Use KBUILD_CFLAGS instead of KCFLAGS when building the vDSO
Since commit ce99d0bf31 ("kbuild: clear LDFLAGS in the top Makefile"),
the top-level Makefile caters to this.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
RISC-V uses the macro __riscv_xlen, predefined by GCC, to
make the distinction between 32 or 64 bit code.
However, sparse doesn't know anything about this macro
which lead to wrong warnings and failures.
Fix this by adding a define of __riscv_xlen to CHECKFLAGS
and add one for __riscv too.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This cleans up the module support that was commited earlier to work with
what's actually emitted from our GCC port as it lands upstream. Most of
the work here is adding new relocations to the kernel.
There's some limitations on module loading imposed by the kernel:
* The kernel doesn't support linker relaxation, which is necessary to
support R_RISCV_ALIGN. In order to get reliable module building
you're going to need to a GCC that supports the new '-mno-relax',
which IIRC isn't going to be out until 8.1.0. It's somewhat unlikely
that R_RISCV_ALIGN will appear in a module even without '-mno-relax'
support, so issues shouldn't be common.
* There is no large code model for RISC-V, which means modules must be
loaded within a 32-bit signed offset of the kernel. We don't
currently have any mechanism for ensuring this memory remains free or
moving pages around, so issues here might be common.
I fixed a singcle merge conflict in arch/riscv/kernel/Makefile.
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>
Now recordmcount.pl recognizes RISC-V object files. For the mechanism to
work, we have to disable the linker relaxation.
Cc: Greentime Hu <greentime@andestech.com>
Signed-off-by: Alan Kao <alankao@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.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>
Palmer Dabbelt