[PATCHv3 2/6] arm64: don't use GENERIC_IRQ_MULTI_HANDLER

[Mark Rutland]

From: Marc Zyngier <m...@kernel.org>

In subsequent patches we want to allow irqchip drivers to register as
FIQ handlers, with a set_handle_fiq() function. To keep the IRQ/FIQ
paths similar, we want arm64 to provide both set_handle_irq() and
set_handle_fiq(), rather than using GENERIC_IRQ_MULTI_HANDLER for the
former.

This patch adds an arm64-specific implementation of set_handle_irq().
There should be no functional change as a result of this patch.

Signed-off-by: Marc Zyngier <m...@kernel.org>
[Mark: use a single handler pointer]
Signed-off-by: Mark Rutland <mark.rutl...@arm.com>
Tested-by: Hector Martin <mar...@marcan.st>
Cc: Catalin Marinas <catalin.mari...@arm.com>
Cc: James Morse <james.mo...@arm.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Will Deacon <w...@kernel.org>
---
 arch/arm64/Kconfig           |  1 -
 arch/arm64/include/asm/irq.h |  3 +++
 arch/arm64/kernel/irq.c      | 11 +++++++++++
 3 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 5656e7aacd69..e7d2405be71f 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -110,7 +110,6 @@ config ARM64
        select GENERIC_EARLY_IOREMAP
        select GENERIC_IDLE_POLL_SETUP
        select GENERIC_IRQ_IPI
-       select GENERIC_IRQ_MULTI_HANDLER
        select GENERIC_IRQ_PROBE
        select GENERIC_IRQ_SHOW
        select GENERIC_IRQ_SHOW_LEVEL
diff --git a/arch/arm64/include/asm/irq.h b/arch/arm64/include/asm/irq.h
index b2b0c6405eb0..8391c6f6f746 100644
--- a/arch/arm64/include/asm/irq.h
+++ b/arch/arm64/include/asm/irq.h
@@ -8,6 +8,9 @@
 
 struct pt_regs;
 
+int set_handle_irq(void (*handle_irq)(struct pt_regs *));
+#define set_handle_irq set_handle_irq
+
 static inline int nr_legacy_irqs(void)
 {
        return 0;
diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c
index dfb1feab867d..ad63bd50fa7b 100644
--- a/arch/arm64/kernel/irq.c
+++ b/arch/arm64/kernel/irq.c
@@ -71,6 +71,17 @@ static void init_irq_stacks(void)
 }
 #endif
 
+void (*handle_arch_irq)(struct pt_regs *) __ro_after_init;
+
+int __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
+{
+       if (handle_arch_irq)
+               return -EBUSY;
+
+       handle_arch_irq = handle_irq;
+       return 0;
+}
+
 void __init init_IRQ(void)
 {
        init_irq_stacks();
-- 
2.11.0