init: consolidate prototypes in linux/init.h

The init/main.c file contains some extern declarations for functions
defined in architecture code, and it defines some other functions that are
called from architecture code with a custom prototype. Both of those
result in warnings with 'make W=1':

init/calibrate.c:261:37: error: no previous prototype for 'calibrate_delay_is_known' [-Werror=missing-prototypes]
init/main.c:790:20: error: no previous prototype for 'mem_encrypt_init' [-Werror=missing-prototypes]
init/main.c:792:20: error: no previous prototype for 'poking_init' [-Werror=missing-prototypes]
arch/arm64/kernel/irq.c:122:13: error: no previous prototype for 'init_IRQ' [-Werror=missing-prototypes]
arch/arm64/kernel/time.c:55:13: error: no previous prototype for 'time_init' [-Werror=missing-prototypes]
arch/x86/kernel/process.c:935:13: error: no previous prototype for 'arch_post_acpi_subsys_init' [-Werror=missing-prototypes]
init/calibrate.c:261:37: error: no previous prototype for 'calibrate_delay_is_known' [-Werror=missing-prototypes]
kernel/fork.c:991:20: error: no previous prototype for 'arch_task_cache_init' [-Werror=missing-prototypes]

Add prototypes for all of these in include/linux/init.h or another
appropriate header, and remove the duplicate declarations from
architecture specific code.

[sfr@canb.auug.org.au: declare time_init_early()]
Link: https://lkml.kernel.org/r/20230519124311.5167221c@canb.auug.org.au
Link: https://lkml.kernel.org/r/20230517131102.934196-12-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

irqchip/riscv-intc: Allow drivers to directly discover INTC hwnode

Various RISC-V drivers (such as SBI IPI, SBI Timer, SBI PMU, and
KVM RISC-V) don't have associated DT node but these drivers need
standard per-CPU (local) interrupts defined by the RISC-V privileged
specification.

We add riscv_get_intc_hwnode() in arch/riscv which allows RISC-V
drivers not having DT node to discover INTC hwnode which in-turn
helps these drivers to map per-CPU (local) interrupts provided
by the INTC driver.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230328035223.1480939-3-apatel@ventanamicro.com

riscv: irq: Fix no prototype warning

Fix the following W=1 kernel compilation warning:
arch/riscv/kernel/irq.c:19:13: warning: no previous prototype for ‘init_IRQ’ [-Wmissing-prototypes]
19 | void __init init_IRQ(void)
| ^~~~~~~~

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Nanyong Sun <sunnanyong@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

clocksource/drivers/timer-riscv: Use per-CPU timer interrupt

Instead of directly calling RISC-V timer interrupt handler from
RISC-V local interrupt conntroller driver, this patch implements
RISC-V timer interrupt as a per-CPU interrupt using per-CPU APIs
of Linux IRQ subsystem.

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

irqchip: RISC-V per-HART local interrupt controller driver

The RISC-V per-HART local interrupt controller manages software
interrupts, timer interrupts, external interrupts (which are routed
via the platform level interrupt controller) and other per-HART
local interrupts.

We add a driver for the RISC-V local interrupt controller, which
eventually replaces the RISC-V architecture code, allowing for a
better split between arch code and drivers.

The driver is compliant with RISC-V Hart-Level Interrupt Controller
DT bindings located at:
Documentation/devicetree/bindings/interrupt-controller/riscv,cpu-intc.txt

Co-developed-by: Palmer Dabbelt <palmer@dabbelt.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
[Palmer: Cleaned up warnings]
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>

RISC-V: self-contained IPI handling routine

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>

riscv: add missing header file includes

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>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 286

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 as published by
the free software foundation version 2 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

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 97 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141901.025053186@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

RISC-V: remove INTERRUPT_CAUSE_* defines from asm/irq.h

These are only of use to the local irq controller driver, so add them in
that driver implementation instead, which will be submitted soon.

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

RISC-V: simplify software interrupt / IPI code

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>

RISC-V: Device, timer, IRQs, and the SBI

This patch contains code that interfaces with devices that are mandated
by the RISC-V supervisor specification and that don't have explicit
drivers anywhere else in the tree. This includes the staticly defined
interrupts, the CSR-mapped timer, and virtualized SBI devices.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>