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-rw-r--r--arch/m68k/q40/q40ints.c332
1 files changed, 332 insertions, 0 deletions
diff --git a/arch/m68k/q40/q40ints.c b/arch/m68k/q40/q40ints.c
new file mode 100644
index 000000000..d15057d34
--- /dev/null
+++ b/arch/m68k/q40/q40ints.c
@@ -0,0 +1,332 @@
+/*
+ * 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/machdep.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:
+ pr_warn("%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 irqreturn_t q40_timer_int(int irq, void *dev_id)
+{
+ 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) {
+ unsigned long flags;
+
+ local_irq_save(flags);
+ legacy_timer_tick(1);
+ timer_heartbeat();
+ local_irq_restore(flags);
+ }
+ return IRQ_HANDLED;
+}
+
+void q40_sched_init (void)
+{
+ int timer_irq;
+
+ timer_irq = Q40_IRQ_FRAME;
+
+ if (request_irq(timer_irq, q40_timer_int, 0, "timer", NULL))
+ 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
+ /*pr_warn("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;
+ /*pr_info("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) {
+ pr_warn("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)
+ pr_warn("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)
+ pr_info("disable_irq nesting count %d\n",
+ mext_disabled);
+ }
+}
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