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Diffstat (limited to 'src/drivers/pc80/i8259.c')
-rw-r--r--src/drivers/pc80/i8259.c75
1 files changed, 39 insertions, 36 deletions
diff --git a/src/drivers/pc80/i8259.c b/src/drivers/pc80/i8259.c
index 6f97c56dcf..2ad46e4070 100644
--- a/src/drivers/pc80/i8259.c
+++ b/src/drivers/pc80/i8259.c
@@ -2,6 +2,7 @@
* This file is part of the coreboot project.
*
* Copyright (C) 2009 coresystems GmbH
+ * Copyright (C) 2013 Sage Electronic Engineering, LLC.
*
* 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
@@ -21,40 +22,44 @@
#include <pc80/i8259.h>
#include <console/console.h>
-#define MASTER_PIC_ICW1 0x20
-#define SLAVE_PIC_ICW1 0xa0
-#define ICW_SELECT (1 << 4)
-#define OCW_SELECT (0 << 4)
-#define ADI (1 << 2)
-#define SNGL (1 << 1)
-#define IC4 (1 << 0)
-
-#define MASTER_PIC_ICW2 0x21
-#define SLAVE_PIC_ICW2 0xa1
-#define INT_VECTOR_MASTER 0x20
-#define IRQ0 0x00
-#define IRQ1 0x01
-#define INT_VECTOR_SLAVE 0x28
-#define IRQ8 0x00
-#define IRQ9 0x01
-
-#define MASTER_PIC_ICW3 0x21
-#define CASCADED_PIC (1 << 2)
-
-#define MASTER_PIC_ICW4 0x21
-#define SLAVE_PIC_ICW4 0xa1
-#define MICROPROCESSOR_MODE (1 << 0)
-
-#define SLAVE_PIC_ICW3 0xa1
-#define SLAVE_ID 0x02
-
-#define MASTER_PIC_OCW1 0x21
-#define SLAVE_PIC_OCW1 0xa1
-#define IRQ2 (1 << 2)
-#define ALL_IRQS 0xff
-
-#define ELCR1 0x4d0
-#define ELCR2 0x4d1
+/* Read the current PIC IRQ mask */
+u16 pic_read_irq_mask(void)
+{
+ u16 mask;
+ int i;
+
+ mask = inb(MASTER_PIC_OCW1) | (inb(SLAVE_PIC_OCW1) << 8);
+
+ printk(BIOS_DEBUG, "8259 PIC: OCW1 IRQ Mask: 0x%x\n", mask);
+ printk(BIOS_SPEW, "\tEnabled IRQs (0 = Unmasked, 1 = Masked off):\n"
+ "\t\tMaster\t\tSlave\n");
+ for(i = 0; i <= 7; i++) {
+ printk(BIOS_SPEW, "\t\tIRQ%X: %x\t\tIRQ%X: %x\n",
+ i, (mask >> i) & 1, i + 8, (mask >> (i + 8)) & 1);
+ }
+ return mask;
+}
+
+/*
+ * Write an IRQ mask to the PIC:
+ * IRQA is bit 0xA in the 16 bit bitmask (OCW1)
+ */
+void pic_write_irq_mask(u16 mask)
+{
+ outb(mask, MASTER_PIC_OCW1);
+ outb(mask >> 8, SLAVE_PIC_OCW1);
+}
+
+/*
+ * The PIC IRQs default to masked off
+ * Allow specific IRQs to be enabled (1)
+ * or disabled by (0) the user
+ */
+void pic_irq_enable(u8 int_num, u8 mask)
+{
+ pic_write_irq_mask(pic_read_irq_mask() & ~(mask << int_num));
+ pic_read_irq_mask();
+}
void setup_i8259(void)
{
@@ -113,14 +118,12 @@ void i8259_configure_irq_trigger(int int_num, int is_level_triggered)
{
u16 int_bits = inb(ELCR1) | (((u16)inb(ELCR2)) << 8);
- printk(BIOS_SPEW, "%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 */
- printk(BIOS_SPEW, "%s: try to set interrupts 0x%x\n", __func__, int_bits);
outb((u8)(int_bits & 0xff), ELCR1);
outb((u8)(int_bits >> 8), ELCR2);