From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- arch/mips/sgi-ip27/ip27-irqno.c | 48 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 arch/mips/sgi-ip27/ip27-irqno.c (limited to 'arch/mips/sgi-ip27/ip27-irqno.c') diff --git a/arch/mips/sgi-ip27/ip27-irqno.c b/arch/mips/sgi-ip27/ip27-irqno.c new file mode 100644 index 000000000..957ab58e1 --- /dev/null +++ b/arch/mips/sgi-ip27/ip27-irqno.c @@ -0,0 +1,48 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ +#include +#include +#include + +#include + +static DECLARE_BITMAP(irq_map, NR_IRQS); + +int allocate_irqno(void) +{ + int irq; + +again: + irq = find_first_zero_bit(irq_map, NR_IRQS); + + if (irq >= NR_IRQS) + return -ENOSPC; + + if (test_and_set_bit(irq, irq_map)) + goto again; + + return irq; +} + +/* + * Allocate the 16 legacy interrupts for i8259 devices. This happens early + * in the kernel initialization so treating allocation failure as BUG() is + * ok. + */ +void __init alloc_legacy_irqno(void) +{ + int i; + + for (i = 0; i <= 16; i++) + BUG_ON(test_and_set_bit(i, irq_map)); +} + +void free_irqno(unsigned int irq) +{ + smp_mb__before_atomic(); + clear_bit(irq, irq_map); + smp_mb__after_atomic(); +} -- cgit v1.2.3