diff options
Diffstat (limited to 'arch/mips/mips-boards/atlas/atlas_int.c')
-rw-r--r-- | arch/mips/mips-boards/atlas/atlas_int.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/arch/mips/mips-boards/atlas/atlas_int.c b/arch/mips/mips-boards/atlas/atlas_int.c new file mode 100644 index 0000000..8f1d875 --- /dev/null +++ b/arch/mips/mips-boards/atlas/atlas_int.c @@ -0,0 +1,142 @@ +/* + * 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 MIPS + * Atlas board. + * + */ +#include <linux/compiler.h> +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/kernel_stat.h> + +#include <asm/irq.h> +#include <asm/io.h> +#include <asm/mips-boards/atlas.h> +#include <asm/mips-boards/atlasint.h> +#include <asm/gdb-stub.h> + + +static struct atlas_ictrl_regs *atlas_hw0_icregs; + +extern asmlinkage void mipsIRQ(void); + +#if 0 +#define DEBUG_INT(x...) printk(x) +#else +#define DEBUG_INT(x...) +#endif + +void disable_atlas_irq(unsigned int irq_nr) +{ + atlas_hw0_icregs->intrsten = (1 << (irq_nr-ATLASINT_BASE)); + iob(); +} + +void enable_atlas_irq(unsigned int irq_nr) +{ + atlas_hw0_icregs->intseten = (1 << (irq_nr-ATLASINT_BASE)); + iob(); +} + +static unsigned int startup_atlas_irq(unsigned int irq) +{ + enable_atlas_irq(irq); + return 0; /* never anything pending */ +} + +#define shutdown_atlas_irq disable_atlas_irq + +#define mask_and_ack_atlas_irq disable_atlas_irq + +static void end_atlas_irq(unsigned int irq) +{ + if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS))) + enable_atlas_irq(irq); +} + +static struct hw_interrupt_type atlas_irq_type = { + "Atlas", + startup_atlas_irq, + shutdown_atlas_irq, + enable_atlas_irq, + disable_atlas_irq, + mask_and_ack_atlas_irq, + end_atlas_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; +} + +void atlas_hw0_irqdispatch(struct pt_regs *regs) +{ + unsigned long int_status; + int irq; + + int_status = atlas_hw0_icregs->intstatus; + + /* if int_status == 0, then the interrupt has already been cleared */ + if (unlikely(int_status == 0)) + return; + + irq = ATLASINT_BASE + ls1bit32(int_status); + + DEBUG_INT("atlas_hw0_irqdispatch: irq=%d\n", irq); + + do_IRQ(irq, regs); +} + +void __init arch_init_irq(void) +{ + int i; + + atlas_hw0_icregs = (struct atlas_ictrl_regs *)ioremap (ATLAS_ICTRL_REGS_BASE, sizeof(struct atlas_ictrl_regs *)); + + /* + * Mask out all interrupt by writing "1" to all bit position in + * the interrupt reset reg. + */ + atlas_hw0_icregs->intrsten = 0xffffffff; + + /* Now safe to set the exception vector. */ + set_except_vector(0, mipsIRQ); + + for (i = ATLASINT_BASE; i <= ATLASINT_END; i++) { + irq_desc[i].status = IRQ_DISABLED; + irq_desc[i].action = 0; + irq_desc[i].depth = 1; + irq_desc[i].handler = &atlas_irq_type; + spin_lock_init(&irq_desc[i].lock); + } +} |