diff options
Diffstat (limited to 'kernel/arch/m68k/q40/q40ints.c')
| -rw-r--r-- | kernel/arch/m68k/q40/q40ints.c | 326 |
1 files changed, 326 insertions, 0 deletions
diff --git a/kernel/arch/m68k/q40/q40ints.c b/kernel/arch/m68k/q40/q40ints.c new file mode 100644 index 000000000..513f9bb17 --- /dev/null +++ b/kernel/arch/m68k/q40/q40ints.c @@ -0,0 +1,326 @@ +/* + * arch/m68k/q40/q40ints.c + * + * Copyright (C) 1999,2001 Richard Zidlicky + * + * 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. + * + * .. used to be loosely based on bvme6000ints.c + * + */ + +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/irq.h> + +#include <asm/ptrace.h> +#include <asm/traps.h> + +#include <asm/q40_master.h> +#include <asm/q40ints.h> + +/* + * Q40 IRQs are defined as follows: + * 3,4,5,6,7,10,11,14,15 : ISA dev IRQs + * 16-31: reserved + * 32 : keyboard int + * 33 : frame int (50/200 Hz periodic timer) + * 34 : sample int (10/20 KHz periodic timer) + * +*/ + +static void q40_irq_handler(unsigned int, struct pt_regs *fp); +static void q40_irq_enable(struct irq_data *data); +static void q40_irq_disable(struct irq_data *data); + +unsigned short q40_ablecount[35]; +unsigned short q40_state[35]; + +static unsigned int q40_irq_startup(struct irq_data *data) +{ + unsigned int irq = data->irq; + + /* test for ISA ints not implemented by HW */ + switch (irq) { + case 1: case 2: case 8: case 9: + case 11: case 12: case 13: + printk("%s: ISA IRQ %d not implemented by HW\n", __func__, irq); + /* FIXME return -ENXIO; */ + } + return 0; +} + +static void q40_irq_shutdown(struct irq_data *data) +{ +} + +static struct irq_chip q40_irq_chip = { + .name = "q40", + .irq_startup = q40_irq_startup, + .irq_shutdown = q40_irq_shutdown, + .irq_enable = q40_irq_enable, + .irq_disable = q40_irq_disable, +}; + +/* + * void q40_init_IRQ (void) + * + * Parameters: None + * + * Returns: Nothing + * + * This function is called during kernel startup to initialize + * the q40 IRQ handling routines. + */ + +static int disabled; + +void __init q40_init_IRQ(void) +{ + m68k_setup_irq_controller(&q40_irq_chip, handle_simple_irq, 1, + Q40_IRQ_MAX); + + /* setup handler for ISA ints */ + m68k_setup_auto_interrupt(q40_irq_handler); + + m68k_irq_startup_irq(IRQ_AUTO_2); + m68k_irq_startup_irq(IRQ_AUTO_4); + + /* now enable some ints.. */ + master_outb(1, EXT_ENABLE_REG); /* ISA IRQ 5-15 */ + + /* make sure keyboard IRQ is disabled */ + master_outb(0, KEY_IRQ_ENABLE_REG); +} + + +/* + * this stuff doesn't really belong here.. + */ + +int ql_ticks; /* 200Hz ticks since last jiffie */ +static int sound_ticks; + +#define SVOL 45 + +void q40_mksound(unsigned int hz, unsigned int ticks) +{ + /* for now ignore hz, except that hz==0 switches off sound */ + /* simply alternate the ampl (128-SVOL)-(128+SVOL)-..-.. at 200Hz */ + if (hz == 0) { + if (sound_ticks) + sound_ticks = 1; + + *DAC_LEFT = 128; + *DAC_RIGHT = 128; + + return; + } + /* sound itself is done in q40_timer_int */ + if (sound_ticks == 0) + sound_ticks = 1000; /* pretty long beep */ + sound_ticks = ticks << 1; +} + +static irq_handler_t q40_timer_routine; + +static irqreturn_t q40_timer_int (int irq, void * dev) +{ + ql_ticks = ql_ticks ? 0 : 1; + if (sound_ticks) { + unsigned char sval=(sound_ticks & 1) ? 128-SVOL : 128+SVOL; + sound_ticks--; + *DAC_LEFT=sval; + *DAC_RIGHT=sval; + } + + if (!ql_ticks) + q40_timer_routine(irq, dev); + return IRQ_HANDLED; +} + +void q40_sched_init (irq_handler_t timer_routine) +{ + int timer_irq; + + q40_timer_routine = timer_routine; + timer_irq = Q40_IRQ_FRAME; + + if (request_irq(timer_irq, q40_timer_int, 0, + "timer", q40_timer_int)) + panic("Couldn't register timer int"); + + master_outb(-1, FRAME_CLEAR_REG); + master_outb( 1, FRAME_RATE_REG); +} + + +/* + * tables to translate bits into IRQ numbers + * it is a good idea to order the entries by priority + * +*/ + +struct IRQ_TABLE{ unsigned mask; int irq ;}; +#if 0 +static struct IRQ_TABLE iirqs[]={ + {Q40_IRQ_FRAME_MASK,Q40_IRQ_FRAME}, + {Q40_IRQ_KEYB_MASK,Q40_IRQ_KEYBOARD}, + {0,0}}; +#endif +static struct IRQ_TABLE eirqs[] = { + { .mask = Q40_IRQ3_MASK, .irq = 3 }, /* ser 1 */ + { .mask = Q40_IRQ4_MASK, .irq = 4 }, /* ser 2 */ + { .mask = Q40_IRQ14_MASK, .irq = 14 }, /* IDE 1 */ + { .mask = Q40_IRQ15_MASK, .irq = 15 }, /* IDE 2 */ + { .mask = Q40_IRQ6_MASK, .irq = 6 }, /* floppy, handled elsewhere */ + { .mask = Q40_IRQ7_MASK, .irq = 7 }, /* par */ + { .mask = Q40_IRQ5_MASK, .irq = 5 }, + { .mask = Q40_IRQ10_MASK, .irq = 10 }, + {0,0} +}; + +/* complain only this many times about spurious ints : */ +static int ccleirq=60; /* ISA dev IRQs*/ +/*static int cclirq=60;*/ /* internal */ + +/* FIXME: add shared ints,mask,unmask,probing.... */ + +#define IRQ_INPROGRESS 1 +/*static unsigned short saved_mask;*/ +//static int do_tint=0; + +#define DEBUG_Q40INT +/*#define IP_USE_DISABLE *//* would be nice, but crashes ???? */ + +static int mext_disabled=0; /* ext irq disabled by master chip? */ +static int aliased_irq=0; /* how many times inside handler ?*/ + + +/* got interrupt, dispatch to ISA or keyboard/timer IRQs */ +static void q40_irq_handler(unsigned int irq, struct pt_regs *fp) +{ + unsigned mir, mer; + int i; + +//repeat: + mir = master_inb(IIRQ_REG); +#ifdef CONFIG_BLK_DEV_FD + if ((mir & Q40_IRQ_EXT_MASK) && + (master_inb(EIRQ_REG) & Q40_IRQ6_MASK)) { + floppy_hardint(); + return; + } +#endif + switch (irq) { + case 4: + case 6: + do_IRQ(Q40_IRQ_SAMPLE, fp); + return; + } + if (mir & Q40_IRQ_FRAME_MASK) { + do_IRQ(Q40_IRQ_FRAME, fp); + master_outb(-1, FRAME_CLEAR_REG); + } + if ((mir & Q40_IRQ_SER_MASK) || (mir & Q40_IRQ_EXT_MASK)) { + mer = master_inb(EIRQ_REG); + for (i = 0; eirqs[i].mask; i++) { + if (mer & eirqs[i].mask) { + irq = eirqs[i].irq; +/* + * There is a little mess wrt which IRQ really caused this irq request. The + * main problem is that IIRQ_REG and EIRQ_REG reflect the state when they + * are read - which is long after the request came in. In theory IRQs should + * not just go away but they occasionally do + */ + if (irq > 4 && irq <= 15 && mext_disabled) { + /*aliased_irq++;*/ + goto iirq; + } + if (q40_state[irq] & IRQ_INPROGRESS) { + /* some handlers do local_irq_enable() for irq latency reasons, */ + /* however reentering an active irq handler is not permitted */ +#ifdef IP_USE_DISABLE + /* in theory this is the better way to do it because it still */ + /* lets through eg the serial irqs, unfortunately it crashes */ + disable_irq(irq); + disabled = 1; +#else + /*printk("IRQ_INPROGRESS detected for irq %d, disabling - %s disabled\n", + irq, disabled ? "already" : "not yet"); */ + fp->sr = (((fp->sr) & (~0x700))+0x200); + disabled = 1; +#endif + goto iirq; + } + q40_state[irq] |= IRQ_INPROGRESS; + do_IRQ(irq, fp); + q40_state[irq] &= ~IRQ_INPROGRESS; + + /* naively enable everything, if that fails than */ + /* this function will be reentered immediately thus */ + /* getting another chance to disable the IRQ */ + + if (disabled) { +#ifdef IP_USE_DISABLE + if (irq > 4) { + disabled = 0; + enable_irq(irq); + } +#else + disabled = 0; + /*printk("reenabling irq %d\n", irq); */ +#endif + } +// used to do 'goto repeat;' here, this delayed bh processing too long + return; + } + } + if (mer && ccleirq > 0 && !aliased_irq) { + printk("ISA interrupt from unknown source? EIRQ_REG = %x\n",mer); + ccleirq--; + } + } + iirq: + mir = master_inb(IIRQ_REG); + /* should test whether keyboard irq is really enabled, doing it in defhand */ + if (mir & Q40_IRQ_KEYB_MASK) + do_IRQ(Q40_IRQ_KEYBOARD, fp); + + return; +} + +void q40_irq_enable(struct irq_data *data) +{ + unsigned int irq = data->irq; + + if (irq >= 5 && irq <= 15) { + mext_disabled--; + if (mext_disabled > 0) + printk("q40_irq_enable : nested disable/enable\n"); + if (mext_disabled == 0) + master_outb(1, EXT_ENABLE_REG); + } +} + + +void q40_irq_disable(struct irq_data *data) +{ + unsigned int irq = data->irq; + + /* disable ISA iqs : only do something if the driver has been + * verified to be Q40 "compatible" - right now IDE, NE2K + * Any driver should not attempt to sleep across disable_irq !! + */ + + if (irq >= 5 && irq <= 15) { + master_outb(0, EXT_ENABLE_REG); + mext_disabled++; + if (mext_disabled > 1) + printk("disable_irq nesting count %d\n",mext_disabled); + } +} |