Right now the RISC-V timer driver is convoluted to support:
1. Linux RISC-V S-mode (with MMU) where it will use TIME CSR for
clocksource and SBI timer calls for clockevent device.
2. Linux RISC-V M-mode (without MMU) where it will use CLINT MMIO
counter register for clocksource and CLINT MMIO compare register
for clockevent device.
We now have a separate CLINT timer driver which also provide CLINT
based IPI operations so let's remove CLINT MMIO related code from
arch/riscv directory and RISC-V timer driver.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Tested-by: Emil Renner Berhing <kernel@esmil.dk>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
We add mechanism to set custom IPI operations so that CLINT driver
from drivers directory can provide custom IPI operations.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Tested-by: Emil Renner Berhing <kernel@esmil.dk>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Support for arch_irq_work_raise() and arch_irq_work_has_interrupt() was
missing from riscv (a prerequisite for FULL_NOHZ).
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Currently, the IPI handling routine riscv_software_interrupt() does
not take any argument and also does not perform irq_enter()/irq_exit().
This patch makes IPI handling routine more self-contained by:
1. Passing "pt_regs *" argument
2. Explicitly doing irq_enter()/irq_exit()
3. Explicitly save/restore "pt_regs *" using set_irq_regs()
With above changes, IPI handling routine does not depend on caller
function to perform irq_enter()/irq_exit() and save/restore of
"pt_regs *" hence its more self-contained. This also enables us
to call IPI handling routine from IRQCHIP drivers.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
The riscv_cpuid_to_hartid_mask() API should be exported to allow
building KVM RISC-V as loadable module.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
This patch fixes the IPI(inner processor interrupt) missing issue. It
failed because it used hartid_mask to iterate for_each_cpu(), however the
cpu_mask and hartid_mask may not be always the same. It will never send the
IPI to hartid 4 because it will be skipped in for_each_cpu loop in my case.
We can reproduce this case in Qemu sifive_u machine by this command.
qemu-system-riscv64 -nographic -smp 5 -m 1G -M sifive_u -kernel \
arch/riscv/boot/loader
It will hang in csd_lock_wait(csd) because the csd_unlock(csd) is not
called. It is not called because hartid 4 doesn't receive the IPI to
release this lock. The caller hart doesn't send the IPI to hartid 4 is
because of hartid 4 is skipped in for_each_cpu(). It will be skipped is
because "(cpu) < nr_cpu_ids" is not true. The hartid is 4 and nr_cpu_ids
is 4. Therefore it should use cpumask in for_each_cpu() instead of
hartid_mask.
/* Send a message to all CPUs in the map */
arch_send_call_function_ipi_mask(cfd->cpumask_ipi);
if (wait) {
for_each_cpu(cpu, cfd->cpumask) {
call_single_data_t *csd;
csd = per_cpu_ptr(cfd->csd, cpu);
csd_lock_wait(csd);
}
}
for ((cpu) = -1; \
(cpu) = cpumask_next((cpu), (mask)), \
(cpu) < nr_cpu_ids;)
It could boot to login console after this patch applied.
Fixes: b2d36b5668f6 ("riscv: provide native clint access for M-mode")
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
RISC-V has the concept of a cpu level interrupt controller. The
interface for it is split between a standardized part that is exposed
as bits in the mstatus/sstatus register and the mie/mip/sie/sip
CRS. But the bit to actually trigger IPIs is not standardized and
just mentioned as implementable using MMIO.
Add support for IPIs using MMIO using the SiFive clint layout (which
is also shared by Ariane, Kendryte and the Qemu virt platform).
Additionally the MMIO block also supports the time value and timer
compare registers, so they are also set up using the same OF node.
Support for other layouts should also be relatively easy to add in the
future.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
[paul.walmsley@sifive.com: update include guard format; fix checkpatch
issues; minor commit message cleanup]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Many of the privileged CSRs exist in a supervisor and machine version
that are used very similarly. Provide versions of the CSR names and
fields that map to either the S-mode or M-mode variant depending on
a new CONFIG_RISCV_M_MODE kconfig symbol.
Contains contributions from Damien Le Moal <Damien.LeMoal@wdc.com>
and Paul Walmsley <paul.walmsley@sifive.com>.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de> # for drivers/clocksource, drivers/irqchip
[paul.walmsley@sifive.com: updated to apply]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
sparse identifies several missing prototypes caused by missing
preprocessor include directives:
arch/riscv/kernel/cpufeature.c:16:6: warning: symbol 'has_fpu' was not declared. Should it be static?
arch/riscv/kernel/process.c:26:6: warning: symbol 'arch_cpu_idle' was not declared. Should it be static?
arch/riscv/kernel/reset.c:15:6: warning: symbol 'pm_power_off' was not declared. Should it be static?
arch/riscv/kernel/syscall_table.c:15:6: warning: symbol 'sys_call_table' was not declared. Should it be static?
arch/riscv/kernel/traps.c:149:13: warning: symbol 'trap_init' was not declared. Should it be static?
arch/riscv/kernel/vdso.c:54:5: warning: symbol 'arch_setup_additional_pages' was not declared. Should it be static?
arch/riscv/kernel/smp.c:64:6: warning: symbol 'arch_match_cpu_phys_id' was not declared. Should it be static?
arch/riscv/kernel/module-sections.c:89:5: warning: symbol 'module_frob_arch_sections' was not declared. Should it be static?
arch/riscv/mm/context.c:42:6: warning: symbol 'switch_mm' was not declared. Should it be static?
Fix by including the appropriate header files in the appropriate
source files.
This patch should have no functional impact.
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Export a few symbols used by kvm module. Without this, kvm cannot
be compiled as a module.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alexander Graf <graf@amazon.com>
[paul.walmsley@sifive.com: updated to apply; clarified short patch
description]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Move the initial clearing of the mask from the callers to
riscv_cpuid_to_hartid_mask, and remove the unused !CONFIG_SMP stub.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Don't go through send_ipi_mask, but just set the op bit and then pass
a simple generated hartid mask directly to sbi_send_ipi.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
[paul.walmsley@sifive.com: minor patch description fixes]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Use the special barriers for atomic bitops to make the intention
a little more clear, and use riscv_cpuid_to_hartid_mask instead of
open coding it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
This prepares for adding native non-SBI IPI code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not see http www gnu org
licenses
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 503 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, flush_icache_all is macro-expanded into a SBI call, yet no
asm/sbi.h is included in asm/cacheflush.h. This could be moved to
mm/cacheflush.c instead (SBI call will dominate performance-wise and
there is no worry to not have it inlined.
Currently, flush_icache_mm stays in kernel/smp.c, which looks like a
hack to prevent it from being compiled when CONFIG_SMP=n. It should
also be in mm/cacheflush.c.
Signed-off-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
We should prefer accessing CSRs using their CSR numbers because:
1. It compiles fine with older toolchains.
2. We can use latest CSR names in #define macro names of CSR numbers
as-per RISC-V spec.
3. We can access newly added CSRs even if toolchain does not recognize
newly addes CSRs by name.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
While working on the patches, I found some minor checkpatch issues.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
OF/DT core has a hook for architecture specific logical cpuid to hartid
mapping. By implementing this, we can pass the logical cpu id to cpu
node parsing functions.
Fix the instances where logical cpuid is expected as an argument in
of_get_cpu_node.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This patchset does:
1. Moves MM related code from kernel/setup.c to mm/init.c
2. Implements compile-time fixed mappings
Using fixed mappings, we get earlyprints even without SBI calls.
For example, we can now use kernel parameter
"earlycon=uart8250,mmio,0x10000000"
to get early prints on QEMU virt machine without using SBI calls.
The patchset is tested on QEMU virt machine.
Palmer: It looks like some of the code movement here conflicted with the
patches to move hartid handling around. As far as I can tell the only
changed code was in smp_setup_processor_id(), and I've kept the one in
smp.c.
It is perfectly okay to call riscv_hartid_to_cpuid for a hartid that is
not mapped with an CPU id. It can happen if the calling functions
retrieves the hartid from DT. However, that hartid was never brought
online by the firmware or kernel for any reasons.
No need to BUG() in the above case. A negative error return is
sufficient and the calling function should check for the return value
always.
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, logical CPU id to physical hartid mapping is defined for both
smp and non-smp configurations. This is not required as we need this
only for smp configuration. The mapping function can define directly
boot_cpu_hartid for non-smp use case.
The reverse mapping function i.e. hartid to cpuid can be called for any
valid but not booted harts. So it should return default cpu 0 only if it
is a boot hartid.
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>
Add IPI_CPU_STOP message and use it in smp_send_stop to stop other cpus,
but not itself. Mark cpu offline on reception of IPI_CPU_STOP.
Signed-off-by: Andreas Schwab <schwab@suse.de>
Reviewed-by: Atish Patra <atish.patra@wdc.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>
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>
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>
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.
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 the following on allmodconfig build:
profile.c:(.text+0x3e4): undefined reference to `setup_profiling_timer'
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This contains the various __init C functions, the initial assembly
kernel entry point, and the code to reset the system. When a file was
init-related this patch contains the entire file.
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
Anup Patel