Initial revision

cpu/74xx_7xx/interrupts.c

@@ -0,0 +1,204 @@
+/*
+ * (C) Copyright 2001
+ * Josh Huber <huber@mclx.com>, Mission Critical Linux, Inc.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that 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
+ */
+
+/*
+ * interrupts.c - just enough support for the decrementer/timer
+ */
+
+#include <common.h>
+#include <mpc8xx.h>
+#include <mpc8xx_irq.h>
+#include <asm/processor.h>
+#include <commproc.h>
+#include <command.h>
+
+/****************************************************************************/
+
+unsigned decrementer_count;	     /* count value for 1e6/HZ microseconds */
+
+/****************************************************************************/
+
+static __inline__ unsigned long
+get_msr(void)
+{
+	unsigned long msr;
+
+	asm volatile("mfmsr %0" : "=r" (msr) :);
+	return msr;
+}
+
+static __inline__ void
+set_msr(unsigned long msr)
+{
+	asm volatile("mtmsr %0" : : "r" (msr));
+}
+
+static __inline__ unsigned long
+get_dec(void)
+{
+	unsigned long val;
+
+	asm volatile("mfdec %0" : "=r" (val) :);
+	return val;
+}
+
+
+static __inline__ void
+set_dec(unsigned long val)
+{
+	asm volatile("mtdec %0" : : "r" (val));
+}
+
+
+void
+enable_interrupts(void)
+{
+	set_msr (get_msr() | MSR_EE);
+}
+
+/* returns flag if MSR_EE was set before */
+int
+disable_interrupts(void)
+{
+	ulong msr = get_msr();
+	set_msr (msr & ~MSR_EE);
+	return ((msr & MSR_EE) != 0);
+}
+
+/****************************************************************************/
+
+int interrupt_init(void)
+{
+#ifdef DEBUG
+	printf("interrupt_init: GT main cause reg: %08x:%08x\n",
+	       GTREGREAD(LOW_INTERRUPT_CAUSE_REGISTER),
+	       GTREGREAD(HIGH_INTERRUPT_CAUSE_REGISTER));
+	printf("interrupt_init: ethernet cause regs: %08x %08x %08x\n",
+	       GTREGREAD(ETHERNET0_INTERRUPT_CAUSE_REGISTER),
+	       GTREGREAD(ETHERNET1_INTERRUPT_CAUSE_REGISTER),
+	       GTREGREAD(ETHERNET2_INTERRUPT_CAUSE_REGISTER));
+	printf("interrupt_init: ethernet mask regs:  %08x %08x %08x\n",
+	       GTREGREAD(ETHERNET0_INTERRUPT_MASK_REGISTER),
+	       GTREGREAD(ETHERNET1_INTERRUPT_MASK_REGISTER),
+	       GTREGREAD(ETHERNET2_INTERRUPT_MASK_REGISTER));
+	puts("interrupt_init: setting decrementer_count\n");
+#endif
+	decrementer_count = get_tbclk() / CFG_HZ;
+
+#ifdef DEBUG
+	puts("interrupt_init: setting actual decremter\n");
+#endif
+	set_dec (get_tbclk() / CFG_HZ);
+
+#ifdef DEBUG
+	printf("interrupt_init: enabling interrupts (msr = %08lx)\n",
+		get_msr());
+#endif
+	set_msr (get_msr() | MSR_EE);
+
+#ifdef DEBUG
+	printf("interrupt_init: done. (msr = %08lx)\n", get_msr());
+#endif
+	return (0);
+}
+
+/****************************************************************************/
+
+/*
+ * Handle external interrupts
+ */
+void
+external_interrupt(struct pt_regs *regs)
+{
+	puts("external_interrupt (oops!)\n");
+}
+
+volatile ulong timestamp = 0;
+
+/*
+ * timer_interrupt - gets called when the decrementer overflows,
+ * with interrupts disabled.
+ * Trivial implementation - no need to be really accurate.
+ */
+void
+timer_interrupt(struct pt_regs *regs)
+{
+	set_dec(decrementer_count);
+	timestamp++;
+
+#if defined(CONFIG_WATCHDOG)
+	if ((timestamp % (CFG_HZ / 2)) == 0) {
+#if defined(CONFIG_PCIPPC2)
+		extern void pcippc2_wdt_reset (void);
+
+		pcippc2_wdt_reset();
+#endif
+	}
+#endif /* CONFIG_WATCHDOG */
+}
+
+/****************************************************************************/
+
+void
+reset_timer(void)
+{
+	timestamp = 0;
+}
+
+ulong
+get_timer(ulong base)
+{
+	return (timestamp - base);
+}
+
+void
+set_timer(ulong t)
+{
+	timestamp = t;
+}
+
+/****************************************************************************/
+
+/*
+ * Install and free a interrupt handler.
+ */
+
+void
+irq_install_handler(int vec, interrupt_handler_t *handler, void *arg)
+{
+
+}
+
+void
+irq_free_handler(int vec)
+{
+
+}
+
+/****************************************************************************/
+
+void
+do_irqinfo(cmd_tbl_t *cmdtp, bd_t *bd, int flag, int argc, char *argv[])
+{
+	puts("IRQ related functions are unimplemented currently.\n");
+}