* (C) Copyright 2002
* Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
*
- * 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
+ * SPDX-License-Identifier: GPL-2.0+
*/
/*
#error "CONFIG_SYS_NUM_IRQS must equal 16 if CONFIG_SYS_NUM_IRQS is defined"
#endif
-int interrupt_init(void)
+int i8259_init(void)
{
u8 i;
- disable_interrupts();
-
/* Mask all interrupts */
outb(0xff, MASTER_PIC + IMR);
outb(0xff, SLAVE_PIC + IMR);
*/
unmask_irq(2);
- enable_interrupts();
+ /* Interrupt 9 should be level triggered (SCI). The OS might do this */
+ configure_irq_trigger(9, true);
return 0;
}
outb(OCW2_SEOI | irq, MASTER_PIC + OCW2);
}
+
+#define ELCR1 0x4d0
+#define ELCR2 0x4d1
+
+void configure_irq_trigger(int int_num, bool is_level_triggered)
+{
+ u16 int_bits = inb(ELCR1) | (((u16)inb(ELCR2)) << 8);
+
+ debug("%s: current interrupts are 0x%x\n", __func__, int_bits);
+ if (is_level_triggered)
+ int_bits |= (1 << int_num);
+ else
+ int_bits &= ~(1 << int_num);
+
+ /* Write new values */
+ debug("%s: try to set interrupts 0x%x\n", __func__, int_bits);
+ outb((u8)(int_bits & 0xff), ELCR1);
+ outb((u8)(int_bits >> 8), ELCR2);
+
+#ifdef PARANOID_IRQ_TRIGGERS
+ /*
+ * Try reading back the new values. This seems like an error but is
+ * not
+ */
+ if (inb(ELCR1) != (int_bits & 0xff)) {
+ printf("%s: lower order bits are wrong: want 0x%x, got 0x%x\n",
+ __func__, (int_bits & 0xff), inb(ELCR1));
+ }
+
+ if (inb(ELCR2) != (int_bits >> 8)) {
+ printf("%s: higher order bits are wrong: want 0x%x, got 0x%x\n",
+ __func__, (int_bits>>8), inb(ELCR2));
+ }
+#endif
+}