PIC i8259: Move #defines and functions to i8259.h

The PIC i8259.c file has a lot of #defines and function
definitions in it.  I am moving these to the i8259.h file
and also adding a few functions to update the PIC IRQ mask
register.  The PIC default configuration has all of its
interrupts masked off except for IRQ2.  IRQ2 is where
the Slave PIC is cascaded from the Master PIC.

Change-Id: I78d505358c29fadbc184137a09120863ea1d5c13
Signed-off-by: Mike Loptien <mike.loptien@se-eng.com>
Reviewed-on: http://review.coreboot.org/5950
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>

2 files changed, 104 insertions, 37 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);
 
diff --git a/src/include/pc80/i8259.h b/src/include/pc80/i8259.h
index 7e99e4baa1..561fc5c863 100644
--- a/src/include/pc80/i8259.h
+++ b/src/include/pc80/i8259.h
@@ -2,6 +2,7 @@
  * This file is part of the coreboot project.
  *
  * Copyright (C) 2007-2009 coresystems GmbH
+ * Copyright (C) 2014 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
@@ -20,10 +21,73 @@
 #ifndef PC80_I8259_H
 #define PC80_I8259_H
 
-void setup_i8259(void);
+/*
+ * IRQ numbers and common usage
+ * If an IRQ does not say it is 'Reserved'
+ * then it can be used by a device, though
+ * some systems may not adhere to this map.
+ */
+/* PIC IRQs */
+#define IRQ_DIS		0x1F	/* IRQ is disabled */
+#define IRQ_0		0x00	/* Reserved - Timer IRQ */
+#define IRQ_1		0x01	/* Keyboard controller */
+#define IRQ_2		0x02	/* Reserved - Cascade to Slave PIC */
+#define IRQ_3		0x03	/* Serial Port 2 & 4 */
+#define IRQ_4		0x04	/* Serial Port 1 & 3 */
+#define IRQ_5		0x05	/* Parallel Port 2 & 3 or Sound Card */
+#define IRQ_6		0x06	/* Floppy Disk Controller */
+#define IRQ_7		0x07	/* Parallel Port 1 */
+#define IRQ_8		0x08	/* Reserved - RTC */
+#define IRQ_9		0x09	/* Reserved - ACPI System Control Interrupt */
+#define IRQ_10		0x0A	/* Free or SCSI or NIC */
+#define IRQ_11		0x0B	/* Free or SCSI or NIC */
+#define IRQ_12		0x0C	/* PS/2 Mouse */
+#define IRQ_13		0x0D	/* Reserved - CPU Floating Point Unit */
+#define IRQ_14		0x0E	/* Primary ATA */
+#define IRQ_15		0x0F	/* Secondary ATA */
+
+#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
 
 #define IRQ_LEVEL_TRIGGERED	1
 #define IRQ_EDGE_TRIGGERED	0
+
+u16 pic_read_irq_mask(void);
+void pic_write_irq_mask(u16 mask);
+void pic_irq_enable(u8 int_num, u8 mask);
+void setup_i8259(void);
 void i8259_configure_irq_trigger(int int_num, int is_level_triggered);
 
 #endif /* PC80_I8259_H */