diff options
Diffstat (limited to 'arch/mips/powertv/asic/asic_int.c')
-rw-r--r-- | arch/mips/powertv/asic/asic_int.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/arch/mips/powertv/asic/asic_int.c b/arch/mips/powertv/asic/asic_int.c new file mode 100644 index 0000000..80b2eed --- /dev/null +++ b/arch/mips/powertv/asic/asic_int.c @@ -0,0 +1,125 @@ +/* + * Carsten Langgaard, carstenl@mips.com + * Copyright (C) 2000, 2001, 2004 MIPS Technologies, Inc. + * Copyright (C) 2001 Ralf Baechle + * Portions copyright (C) 2009 Cisco Systems, Inc. + * + * This program is free software; you can distribute it and/or modify it + * under the terms of the GNU General Public License (Version 2) as + * published by the Free Software Foundation. + * + * This program is distributed in the hope 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. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. + * + * Routines for generic manipulation of the interrupts found on the PowerTV + * platform. + * + * The interrupt controller is located in the South Bridge a PIIX4 device + * with two internal 82C95 interrupt controllers. + */ +#include <linux/init.h> +#include <linux/irq.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/kernel_stat.h> +#include <linux/kernel.h> +#include <linux/random.h> + +#include <asm/irq_cpu.h> +#include <linux/io.h> +#include <asm/irq_regs.h> +#include <asm/mips-boards/generic.h> + +#include <asm/mach-powertv/asic_regs.h> + +static DEFINE_SPINLOCK(asic_irq_lock); + +static inline int get_int(void) +{ + unsigned long flags; + int irq; + + spin_lock_irqsave(&asic_irq_lock, flags); + + irq = (asic_read(int_int_scan) >> 4) - 1; + + if (irq == 0 || irq >= NR_IRQS) + irq = -1; + + spin_unlock_irqrestore(&asic_irq_lock, flags); + + return irq; +} + +static void asic_irqdispatch(void) +{ + int irq; + + irq = get_int(); + if (irq < 0) + return; /* interrupt has already been cleared */ + + do_IRQ(irq); +} + +static inline int clz(unsigned long x) +{ + __asm__( + " .set push \n" + " .set mips32 \n" + " clz %0, %1 \n" + " .set pop \n" + : "=r" (x) + : "r" (x)); + + return x; +} + +/* + * Version of ffs that only looks at bits 12..15. + */ +static inline unsigned int irq_ffs(unsigned int pending) +{ + return fls(pending) - 1 + CAUSEB_IP; +} + +/* + * TODO: check how it works under EIC mode. + */ +asmlinkage void plat_irq_dispatch(void) +{ + unsigned int pending = read_c0_cause() & read_c0_status() & ST0_IM; + int irq; + + irq = irq_ffs(pending); + + if (irq == CAUSEF_IP3) + asic_irqdispatch(); + else if (irq >= 0) + do_IRQ(irq); + else + spurious_interrupt(); +} + +void __init arch_init_irq(void) +{ + int i; + + asic_irq_init(); + + /* + * Initialize interrupt exception vectors. + */ + if (cpu_has_veic || cpu_has_vint) { + int nvec = cpu_has_veic ? 64 : 8; + for (i = 0; i < nvec; i++) + set_vi_handler(i, asic_irqdispatch); + } +} |