On the Hifive-U platform, cpu 0 is a masked cpu with less capabilities
than the other cpus. Ignore it for the purpose of determining the
hardware capabilities of the system.
Signed-off-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This patch series now has evolved to contain several related changes.
1. Updated the assorted cleanup series by Palmer.
The original cleanup patch series can be found here.
http://lists.infradead.org/pipermail/linux-riscv/2018-August/001232.html
2. Implemented decoupling linux logical CPU ids from hart id.
Some of the work has been inspired from ARM64.
Tested on QEMU & HighFive Unleashed board with/without SMP enabled.
3. Included Anup's cleanup and IPI stat patch.
All the patch series have been combined to avoid conflicts as a lot of
common code is changed different patch sets. Atish has mostly addressed
review comments and fixed checkpatch errors from Palmer's and Anup's
series.
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This patch set fixes up various failures in the RV32I port. The fixes
are all nominally independent, but are really only testable together
because the RV32I port fails to build without all of them. The patch
set includes:
* The removal of tishift on RV32I targets, as 128-bit integers are not
supported by the toolchain.
* The removal of swiotlb from RV32I targets, since all physical
addresses can be mapped by all hardware on all existing RV32I targets.
* The addition of ummodi3 and udivmoddi4 from an old version of GCC that
was licensed under GPLv2 as generic code, along with their use on
RV32I targets.
* A fix to our page alignment logic within ioremap for RV32I targets.
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
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>
This export is not only not needed, but also breaks symbol versioning
due to being an undeclared assembly export.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Add a variable and a macro to describe FP registers, assuming only D is
supported. FP code is conditional on CONFIG_FPU. The FP regs and FCSR
are copied separately to avoid copying struct padding. Tested by hand and
with the gdb testsuite.
Signed-off-by: Jim Wilson <jimw@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
The RISC-V Linux port doesn't support systems that have the F extension
but don't have the D extension -- we actually don't support systems
without D either, but Alan's patch set is rectifying that soon. For now
I think we can leave this in a semi-broken state and just wait for
Alan's patch set to get merged for proper non-FPU support -- the patch
set is starting to look good, so doing something in-between doesn't seem
like it's worth the work.
I don't think it's worth fretting about support for systems with F but
not D for now: our glibc ABIs are IMAC and IMAFDC so they probably won't
end up being popular. We can always extend this in the future.
CC: Alan Kao <alankao@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
These are just hard coded in the RISC-V port, which doesn't make any
sense. We should probably be setting these from device tree entries
when they exist, but for now I think it's saner to just leave them all
as their default values.
Reviewed-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This patch provides arch_show_interrupts() implementation to
show IPI stats via /proc/interrupts.
Now the contents of /proc/interrupts" will look like below:
CPU0 CPU1 CPU2 CPU3
8: 17 7 6 14 SiFive PLIC 8 virtio0
10: 10 10 9 11 SiFive PLIC 10 ttyS0
IPI0: 170 673 251 79 Rescheduling interrupts
IPI1: 1 12 27 1 Function call interrupts
Signed-off-by: Anup Patel <anup@brainfault.org>
[Atish - Fixed checkpatch errors]
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Changes since v2:
- Remove use of IPI_CALL_WAKEUP because it's being removed
Changes since v1:
- Add stub inline show_ipi_stats() function for !CONFIG_SMP
- Make ipi_names[] dynamically sized at compile time
- Minor beautification of ipi_names[] using tabs
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Currently, /proc/cpuinfo show logical CPU ID as Hart ID which
is in-correct. This patch shows CPU ID and Hart ID separately
in /proc/cpuinfo using cpuid_to_hardid_map().
With this patch, contents of /proc/cpuinfo looks as follows:
processor : 0
hart : 1
isa : rv64imafdc
mmu : sv48
processor : 1
hart : 0
isa : rv64imafdc
mmu : sv48
processor : 2
hart : 2
isa : rv64imafdc
mmu : sv48
processor : 3
hart : 3
isa : rv64imafdc
mmu : sv48
Signed-off-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Setup the cpu_logical_map during boot. Moreover, every SBI call
and PLIC context are based on the physical hartid. Use the logical
CPU to hartid mapping to pass correct hartid to respective functions.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Currently, both Linux CPU id and hart id are same.
This is not recommended as it will lead to discontinuous CPU
indexing in Linux. Moreover, kdump kernel will run from CPU0
which would be absent if we follow existing scheme.
Implement a logical mapping between Linux CPU id and hart
id to decouple these two. Always mark the boot processor as
CPU0 and all other CPUs get the logical CPU id based on their
booting order.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
The secondary harts spin on couple of per cpu variables until both of
these are non-zero so it's not necessary to have any ordering here.
However, WRITE_ONCE should be used to avoid tearing.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
commit f1f1007644 ("mm: add new mmgrab() helper") added a
helper that we missed out on.
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
The old name was a bit odd.
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
It's a bit confusing exactly what this function does: it actually
returns the hartid of an OF processor node, failing with -1 on invalid
nodes. I've changed the name to _hartid() in order to make that a bit
more clear, as well as adding a comment.
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
[Atish: code comment formatting update]
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Currently, irq is enabled before preemption disabling happens.
If the scheduler fired right here and cpu is scheduled then it
may blow up.
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
[Atish: Commit text and code comment formatting update]
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
We shouldn't be directly passing device tree values to userspace, both
because there could be mistakes in device trees and because the kernel
doesn't support arbitrary ISAs.
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
[Atish: checkpatch fix and code comment formatting update]
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
These are just hard coded in the RISC-V port, which doesn't make any
sense. We should probably be setting these from device tree entries
when they exist, but for now I think it's saner to just leave them all
as their default values.
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
The scause is already part of pt_regs so no need to pass
scause as separate arg to do_IRQ().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Only RV64 supports swiotlb. On RV32, it don't select the SWIOTLB.
Signed-off-by: Zong Li <zong@andestech.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
We expect that a kernel with CONFIG_FPU=y can still support no-FPU
machines. To do so, the kernel should first examine the existence of a
FPU, then do nothing if a FPU does exist; otherwise, it should
disable/bypass all FPU-related functions.
In this patch, a new global variable, has_fpu, is created and determined
when parsing the hardware capability from device tree during booting.
This variable is used in those FPU-related functions.
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>
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>
FPU-related logic is separated from normal signal handling path in
this patch. Kernel can easily be configured to exclude those procedures
for no-FPU systems.
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>
We move __fstate_save and __fstate_restore to a new source
file, fpu.S.
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>
Use memblock_end_of_DRAM which provides correct last low memory
PFN. Without that, DMA32 region becomes empty resulting in zero
pages being allocated for DMA32.
This patch is based on earlier patch from palmer which never
merged into 4.19. I just edited the commit text to make more
sense.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
setup_initrd() overwrites initrd_start and initrd_end if __initramfs_size
is larger than 0, which is always true even if there is no embedded
initramfs. This prevents booting qemu with "-initrd" parameter.
Overwriting initrd_start and initrd_end is not necessary since
__initramfs_start and __initramfs_size are used directly in
populate_rootfs() to load the built-in initramfs, so just drop
that code.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Thanks to Christoph Hellwig for pointing out a cleaner way to do this,
as my approach was quite ugly.
CC: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This would be necessary to make non-SMP builds work, but there is
another error in the implementation of our syscall linkage that actually
just causes sys_riscv_flush_icache to never build. I've build tested
this on allnoconfig and allnoconfig+SMP=y, as well as defconfig like
normal.
CC: Christoph Hellwig <hch@infradead.org>
CC: Guenter Roeck <linux@roeck-us.net>
In-Reply-To: <20180809055830.GA17533@infradead.org>
In-Reply-To: <20180809132612.GA31058@roeck-us.net>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Enabling both CONFIG_PERF_EVENTS without !CONFIG_SMP
generates following compilation error.
arch/riscv/include/asm/perf_event.h:80:2: error: expected
specifier-qualifier-list before 'irqreturn_t'
irqreturn_t (*handle_irq)(int irq_num, void *dev);
^~~~~~~~~~~
Include interrupt.h in proper place to avoid compilation
error.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
The stvec's value must be 4 byte alignment by specification definition.
These directives avoid to stvec be set the non-alignment value.
Signed-off-by: Zong Li <zong@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
The RISC-V ISA defines a per-hart real-time clock and timer, which is
present on all systems. The clock is accessed via the 'rdtime'
pseudo-instruction (which reads a CSR), and the timer is set via an SBI
call.
Contains various improvements from Atish Patra <atish.patra@wdc.com>.
Signed-off-by: Dmitriy Cherkasov <dmitriy@oss-tech.org>
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
[hch: remove dead code, add SPDX tags, used riscv_of_processor_hart(),
minor cleanups, merged hotplug cpu support and other improvements
from Atish]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Add support for a routine that dispatches exceptions with the interrupt
flags set to either the IPI or irqdomain code (and the clock source in the
future).
Loosely based on the irq-riscv-int.c irqchip driver from the RISC-V tree.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Rename handle_ipi to riscv_software_interrupt, drop the unused return
value and move the prototype to irq.h together with riscv_timer_interupt.
This allows simplifying the upcoming interrupt handling support.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This code is currently unused and will be added back later in a different
place with the real interrupt and clocksource support.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This code lives entirely within the RISC-V arch code. I've left it
within an "#ifdef CONFIG_EARLY_PRINTK" despite always having
EARLY_PRINTK support on RISC-V just in case someone wants to remove
it.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Adding 4 to sepc is pointless, and is wrong if we executed a 2-byte
compressed breakpoint. This plus a corresponding gdb patch allows
compressed breakpoints to work in gdb. Gdb maintainers have already
agreed that this is the right approach.
Signed-off-by: Jim Wilson <jimw@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
If you use a 64-bit compiler to build a 32-bit kernel then you'll get an
error when building the vDSO due to a library mismatch. The happens
because the relevant "-march" argument isn't supplied to the GCC run
that generates one of the vDSO intermediate files.
I'm not actually sure what the right thing to do here is as I'm not
particularly familiar with the kernel build system. I poked the
documentation and it appears that KCFLAGS is the correct thing to do
(it's suggested that should be used when building modules), but we set
KBUILD_CFLAGS in arch/riscv/Makefile.
This does at least fix the build error.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
These patches for building 32-bit RISC-V kernel.
- Fix the compile errors and warnings on RV32I.
- Fix some incompatible problem on RV32I.
- Add format.h for compatible of print format.
The fixed width integer types format for Elf_Addr will move to
generic header by another patch. For now, there are some warning
about unexpected argument of type on RV32I.
Change in v1:
- Fix some error in v1
- Remove implementation of fixed width integer types format for Elf_Addr.
In riscv_gpr_set, pass regs instead of ®s to user_regset_copyin to fix
gdb segfault.
Signed-off-by: Jim Wilson <jimw@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This file has never existed in the upstream kernel, but it's guarded by
an #ifdef that's also never existed in the upstream kernel. As a part
of our interrupt controller refactoring this header is no longer
necessary, but this reference managed to sneak in anyway.
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
The DT core will call of_platform_default_populate, so it is not
necessary for arch specific code to call it unless there are custom
match entries, auxdata or parent device. Neither of those apply here, so
remove the call.
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: linux-riscv@lists.infradead.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
The R_RISCV_ADD32/R_RISCV_SUB32 relocations should add/subtract the
address of the symbol (without overflow check), not its contents.
Signed-off-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This tag contains some small RISC-V updates I'd like to target for 4.18.
They are all fairly small this time. Here's a short summary, there's
more info in the commits/merges.
* A fix to __clear_user to respect the passed arguments.
* Enough support for the perf subsystem to work with RISC-V's ISA
defined performance counters.
* Support for sparse and cleanups suggested by it.
* Support for R_RISCV_32 (a relocation, not the 32-bit ISA).
* Some MAINTAINERS cleanups.
* The addition of CONFIG_HVC_RISCV_SBI to our defconfig, as it's always
present.
I've given these a simple build+boot test.
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Merge tag 'riscv-for-linus-4.18-merge_window' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux
Pull RISC-V updates from Palmer Dabbelt:
"This contains some small RISC-V updates I'd like to target for 4.18.
They are all fairly small this time. Here's a short summary, there's
more info in the commits/merges:
- a fix to __clear_user to respect the passed arguments.
- enough support for the perf subsystem to work with RISC-V's ISA
defined performance counters.
- support for sparse and cleanups suggested by it.
- support for R_RISCV_32 (a relocation, not the 32-bit ISA).
- some MAINTAINERS cleanups.
- the addition of CONFIG_HVC_RISCV_SBI to our defconfig, as it's
always present.
I've given these a simple build+boot test"
* tag 'riscv-for-linus-4.18-merge_window' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux:
RISC-V: Add CONFIG_HVC_RISCV_SBI=y to defconfig
RISC-V: Handle R_RISCV_32 in modules
riscv/ftrace: Export _mcount when DYNAMIC_FTRACE isn't set
riscv: add riscv-specific predefines to CHECKFLAGS
riscv: split the declaration of __copy_user
riscv: no __user for probe_kernel_address()
riscv: use NULL instead of a plain 0
perf: riscv: Add Document for Future Porting Guide
perf: riscv: preliminary RISC-V support
MAINTAINERS: Update Albert's email, he's back at Berkeley
MAINTAINERS: Add myself as a maintainer for SiFive's drivers
riscv: Fix the bug in memory access fixup code
This patch set contains a handful of fixes that clean up the sparse
results for the RISC-V port. These patches shouldn't have any
functional difference. The patches:
* Use NULL instead of 0.
* Clean up __user annotations.
* Split __copy_user into two functions, to make the __user annotations
valid.
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
With CONFIG_MODVERSIONS=y the R_RISCV_32 relocation is used by the
__kcrctab section.
Signed-off-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
The EXPORT_SYMBOL(_mcount) for RISC-V ended up inside a
CONFIG_DYNAMIC_FTRACE ifdef. If you enable modules without enabling
CONFIG_DYNAMIC_FTRACE then you'll get a build error without this patch
because the modules won't be able to find _mcount.
The new behavior is to export _mcount whenever CONFIG_FUNCTION_TRACER is
defined. This matches what every other architecture is doing.
Signed-off-by: Alan Kao <alankao@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Cc: Zong Li <zong@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
We use a single __copy_user assembly function to copy memory both from
and to userspace. While this works, it triggers sparse errors because
we're implicitly casting between the kernel and user address spaces by
calling __copy_user.
This patch splits the C declaration into a pair of functions,
__asm_copy_{to,from}_user, that have sane semantics WRT __user. This
split make things fine from sparse's point of view. The assembly
implementation keeps a single definition but add a double ENTRY() for it,
one for __asm_copy_to_user and another one for __asm_copy_from_user.
The result is a spare-safe implementation that pays no performance
or code size penalty.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
