diff options
Diffstat (limited to 'arch/mips/lasat/interrupt.c')
-rw-r--r-- | arch/mips/lasat/interrupt.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/arch/mips/lasat/interrupt.c b/arch/mips/lasat/interrupt.c new file mode 100644 index 0000000..1148a2d --- /dev/null +++ b/arch/mips/lasat/interrupt.c @@ -0,0 +1,160 @@ +/* + * Carsten Langgaard, carstenl@mips.com + * Copyright (C) 1999,2000 MIPS Technologies, Inc. All rights reserved. + * + * 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 + * Lasat boards. + */ +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/kernel_stat.h> + +#include <asm/bootinfo.h> +#include <asm/irq.h> +#include <asm/lasat/lasatint.h> +#include <asm/gdb-stub.h> + +static volatile int *lasat_int_status = NULL; +static volatile int *lasat_int_mask = NULL; +static volatile int lasat_int_mask_shift; + +extern asmlinkage void lasatIRQ(void); + +void disable_lasat_irq(unsigned int irq_nr) +{ + unsigned long flags; + + local_irq_save(flags); + *lasat_int_mask &= ~(1 << irq_nr) << lasat_int_mask_shift; + local_irq_restore(flags); +} + +void enable_lasat_irq(unsigned int irq_nr) +{ + unsigned long flags; + + local_irq_save(flags); + *lasat_int_mask |= (1 << irq_nr) << lasat_int_mask_shift; + local_irq_restore(flags); +} + +static unsigned int startup_lasat_irq(unsigned int irq) +{ + enable_lasat_irq(irq); + + return 0; /* never anything pending */ +} + +#define shutdown_lasat_irq disable_lasat_irq + +#define mask_and_ack_lasat_irq disable_lasat_irq + +static void end_lasat_irq(unsigned int irq) +{ + if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS))) + enable_lasat_irq(irq); +} + +static struct hw_interrupt_type lasat_irq_type = { + "Lasat", + startup_lasat_irq, + shutdown_lasat_irq, + enable_lasat_irq, + disable_lasat_irq, + mask_and_ack_lasat_irq, + end_lasat_irq, + NULL +}; + +static inline int ls1bit32(unsigned int x) +{ + int b = 31, s; + + s = 16; if (x << 16 == 0) s = 0; b -= s; x <<= s; + s = 8; if (x << 8 == 0) s = 0; b -= s; x <<= s; + s = 4; if (x << 4 == 0) s = 0; b -= s; x <<= s; + s = 2; if (x << 2 == 0) s = 0; b -= s; x <<= s; + s = 1; if (x << 1 == 0) s = 0; b -= s; + + return b; +} + +static unsigned long (* get_int_status)(void); + +static unsigned long get_int_status_100(void) +{ + return *lasat_int_status & *lasat_int_mask; +} + +static unsigned long get_int_status_200(void) +{ + unsigned long int_status; + + int_status = *lasat_int_status; + int_status &= (int_status >> LASATINT_MASK_SHIFT_200) & 0xffff; + return int_status; +} + +void lasat_hw0_irqdispatch(struct pt_regs *regs) +{ + unsigned long int_status; + int irq; + + int_status = get_int_status(); + + /* if int_status == 0, then the interrupt has already been cleared */ + if (int_status) { + irq = ls1bit32(int_status); + + do_IRQ(irq, regs); + } +} + +void __init arch_init_irq(void) +{ + int i; + + switch (mips_machtype) { + case MACH_LASAT_100: + lasat_int_status = (void *)LASAT_INT_STATUS_REG_100; + lasat_int_mask = (void *)LASAT_INT_MASK_REG_100; + lasat_int_mask_shift = LASATINT_MASK_SHIFT_100; + get_int_status = get_int_status_100; + *lasat_int_mask = 0; + break; + case MACH_LASAT_200: + lasat_int_status = (void *)LASAT_INT_STATUS_REG_200; + lasat_int_mask = (void *)LASAT_INT_MASK_REG_200; + lasat_int_mask_shift = LASATINT_MASK_SHIFT_200; + get_int_status = get_int_status_200; + *lasat_int_mask &= 0xffff; + break; + default: + panic("arch_init_irq: mips_machtype incorrect"); + } + + /* Now safe to set the exception vector. */ + set_except_vector(0, lasatIRQ); + + for (i = 0; i <= LASATINT_END; i++) { + irq_desc[i].status = IRQ_DISABLED; + irq_desc[i].action = 0; + irq_desc[i].depth = 1; + irq_desc[i].handler = &lasat_irq_type; + } +} |