irqchip: Use of_property_read_bool() for boolean properties

It is preferred to use typed property access functions (i.e.
of_property_read_<type> functions) rather than low-level
of_get_property/of_find_property functions for reading properties.
Convert reading boolean properties to to of_property_read_bool().

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Guo Ren <guoren@kernel.org> (csky)
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230310144710.1543070-1-robh@kernel.org

irqchip/csky: Return true/false (not 1/0) from bool functions

Return boolean values ("true" or "false") instead of 1 or 0 from bool
functions.

Signed-off-by: Haowen Bai <baihaowen@meizu.com>
Acked-by: Guo Ren <guoren@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/1647487284-30088-1-git-send-email-baihaowen@meizu.com

irq: remove handle_domain_{irq,nmi}()

Now that entry code handles IRQ entry (including setting the IRQ regs)
before calling irqchip code, irqchip code can safely call
generic_handle_domain_irq(), and there's no functional reason for it to
call handle_domain_irq().

Let's cement this split of responsibility and remove handle_domain_irq()
entirely, updating irqchip drivers to call generic_handle_domain_irq().

For consistency, handle_domain_nmi() is similarly removed and replaced
with a generic_handle_domain_nmi() function which also does not perform
any entry logic.

Previously handle_domain_{irq,nmi}() had a WARN_ON() which would fire
when they were called in an inappropriate context. So that we can
identify similar issues going forward, similar WARN_ON_ONCE() logic is
added to the generic_handle_*() functions, and comments are updated for
clarity and consistency.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>

irq: Fix typos in comments

Fix ~36 single-word typos in the IRQ, irqchip and irqdomain code comments.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

irqchip/csky: fixup handle_irq_perbit break irq

The handle_irq_perbit function loop every bit in hwirq local variable.

handle_irq_perbit(hwirq) {
for_everyt_bit_in(hwirq) {
handle_domain_irq()
->irq_exit()
->invoke_softirq()
->__do_softirq()
->local_irq_enable() // Here will cause new interrupt.
}
}

When new interrupt coming at local_irq_enable, it will finish another
interrupt handler and pull down the interrupt source. But hwirq is the
local variable for handle_irq_perbit(), it can't get new interrupt
controller pending reg status. So we need update hwirq with pending reg
in every loop.

Also change write_relax to writel could prevent stw from fast retire.
When local_irq is enabled, intc regs is really set-in.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Lu Baoquan <lu.baoquan@intellif.com>

irqchip: add C-SKY APB bus interrupt controller

The driver is for C-SKY APB bus interrupt controller. It's a simple
interrupt controller which use pending reg to detect the irq and use
enable/disable reg to mask/unmask interrupt sources.

A lot of SOCs based on C-SKY CPU use the interrupt controller as root
controller.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>