From: Eric W. Biederman Date: Wed, 4 Oct 2006 09:16:39 +0000 (-0700) Subject: [PATCH] genirq: i386 irq: Dynamic irq support X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=3fc471ede99579211c44b6a64829c4318976990f;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git [PATCH] genirq: i386 irq: Dynamic irq support The current implementation of create_irq() is a hack but it is the current hack that msi.c uses, and unfortunately the ``generic'' apic msi ops depend on this hack. Thus we are stuck this hack of assuming irq == vector until the depencencies in the generic msi code are removed. Signed-off-by: Eric W. Biederman Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Benjamin Herrenschmidt Cc: Rajesh Shah Cc: Andi Kleen Cc: "Protasevich, Natalie" Cc: "Luck, Tony" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/arch/i386/kernel/io_apic.c b/arch/i386/kernel/io_apic.c index b3b01894ca69..fca689cfb0c9 100644 --- a/arch/i386/kernel/io_apic.c +++ b/arch/i386/kernel/io_apic.c @@ -2483,6 +2483,54 @@ static int __init ioapic_init_sysfs(void) device_initcall(ioapic_init_sysfs); +#ifdef CONFIG_PCI_MSI +/* + * Dynamic irq allocate and deallocation for MSI + */ +int create_irq(void) +{ + /* Hack of the day: irq == vector. + * + * Ultimately this will be be more general, + * and not depend on the irq to vector identity mapping. + * But this version is needed until msi.c can cope with + * the more general form. + */ + int irq, vector; + unsigned long flags; + vector = assign_irq_vector(AUTO_ASSIGN); + irq = vector; + + if (vector >= 0) { + struct irq_desc *desc; + + spin_lock_irqsave(&vector_lock, flags); + vector_irq[vector] = irq; + irq_vector[irq] = vector; + spin_unlock_irqrestore(&vector_lock, flags); + + set_intr_gate(vector, interrupt[irq]); + + dynamic_irq_init(irq); + } + return irq; +} + +void destroy_irq(unsigned int irq) +{ + unsigned long flags; + unsigned int vector; + + dynamic_irq_cleanup(irq); + + spin_lock_irqsave(&vector_lock, flags); + vector = irq_vector[irq]; + vector_irq[vector] = -1; + irq_vector[irq] = 0; + spin_unlock_irqrestore(&vector_lock, flags); +} +#endif /* CONFIG_PCI_MSI */ + /* -------------------------------------------------------------------------- ACPI-based IOAPIC Configuration -------------------------------------------------------------------------- */