diff options
Diffstat (limited to 'arch/sh/kernel/cpu/irq_imask.c')
-rw-r--r-- | arch/sh/kernel/cpu/irq_imask.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/arch/sh/kernel/cpu/irq_imask.c b/arch/sh/kernel/cpu/irq_imask.c new file mode 100644 index 0000000..f76901e --- /dev/null +++ b/arch/sh/kernel/cpu/irq_imask.c @@ -0,0 +1,116 @@ +/* $Id: irq_imask.c,v 1.1.2.1 2002/11/17 10:53:43 mrbrown Exp $ + * + * linux/arch/sh/kernel/irq_imask.c + * + * Copyright (C) 1999, 2000 Niibe Yutaka + * + * Simple interrupt handling using IMASK of SR register. + * + */ + +/* NOTE: Will not work on level 15 */ + + +#include <linux/ptrace.h> +#include <linux/errno.h> +#include <linux/kernel_stat.h> +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/interrupt.h> +#include <linux/init.h> +#include <linux/bitops.h> + +#include <asm/system.h> +#include <asm/irq.h> + +#include <linux/spinlock.h> +#include <linux/cache.h> +#include <linux/irq.h> + +/* Bitmap of IRQ masked */ +static unsigned long imask_mask = 0x7fff; +static int interrupt_priority = 0; + +static void enable_imask_irq(unsigned int irq); +static void disable_imask_irq(unsigned int irq); +static void shutdown_imask_irq(unsigned int irq); +static void mask_and_ack_imask(unsigned int); +static void end_imask_irq(unsigned int irq); + +#define IMASK_PRIORITY 15 + +static unsigned int startup_imask_irq(unsigned int irq) +{ + /* Nothing to do */ + return 0; /* never anything pending */ +} + +static struct hw_interrupt_type imask_irq_type = { + "SR.IMASK", + startup_imask_irq, + shutdown_imask_irq, + enable_imask_irq, + disable_imask_irq, + mask_and_ack_imask, + end_imask_irq +}; + +void static inline set_interrupt_registers(int ip) +{ + unsigned long __dummy; + + asm volatile("ldc %2, r6_bank\n\t" + "stc sr, %0\n\t" + "and #0xf0, %0\n\t" + "shlr2 %0\n\t" + "cmp/eq #0x3c, %0\n\t" + "bt/s 1f ! CLI-ed\n\t" + " stc sr, %0\n\t" + "and %1, %0\n\t" + "or %2, %0\n\t" + "ldc %0, sr\n" + "1:" + : "=&z" (__dummy) + : "r" (~0xf0), "r" (ip << 4) + : "t"); +} + +static void disable_imask_irq(unsigned int irq) +{ + clear_bit(irq, &imask_mask); + if (interrupt_priority < IMASK_PRIORITY - irq) + interrupt_priority = IMASK_PRIORITY - irq; + + set_interrupt_registers(interrupt_priority); +} + +static void enable_imask_irq(unsigned int irq) +{ + set_bit(irq, &imask_mask); + interrupt_priority = IMASK_PRIORITY - ffz(imask_mask); + + set_interrupt_registers(interrupt_priority); +} + +static void mask_and_ack_imask(unsigned int irq) +{ + disable_imask_irq(irq); +} + +static void end_imask_irq(unsigned int irq) +{ + if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS))) + enable_imask_irq(irq); +} + +static void shutdown_imask_irq(unsigned int irq) +{ + /* Nothing to do */ +} + +void make_imask_irq(unsigned int irq) +{ + disable_irq_nosync(irq); + irq_desc[irq].handler = &imask_irq_type; + enable_irq(irq); +} |